HK1183385A - Method and apparatus for mitigating interference in femtocell deployments - Google Patents

Description

Method and apparatus for interference mitigation in femtocell deployments

Claiming priority based on 35U.S.C § 119

This patent application claims priority from provisional application No.61/359,762, entitled "ADAPTIVERISE-OVER-thermal (rot) method AND NOISE floor applied FOR fed cell UPLINK interference", filed on 29.6.2010, assigned to the assignee of the present application AND hereby expressly incorporated herein by reference; also, this patent application claims priority from provisional application No.61/387,359, entitled "ADAPTIVERISE-OVER-thermal (rot) method AND NOISE floor project FOR fed cell UPLINK inter-feeding", filed on 28.9.2010, assigned to the assignee of the present application AND hereby expressly incorporated herein by reference.

Technical Field

The following description relates generally to wireless network communications, and more particularly to mitigating interference in femtocell deployments.

Background

Wireless communication systems are widely deployed to provide various types of communication content such as voice data and so on. A typical wireless communication system may be a multiple-access system capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc.). Examples of such multiple-access systems may include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, and the like. Further, these systems may conform to technical specifications such as third generation partnership project (3 GPP), 3GPP Long Term Evolution (LTE), Ultra Mobile Broadband (UMB), evolution-data optimized (EV-DO), and so on.

In general, a wireless multiple-access communication system can simultaneously support communication for multiple mobile devices. Each mobile device may communicate with one or more access points via transmissions on forward and reverse links. The forward link (or downlink) refers to the communication link from the access points to the mobile devices, and the reverse link (or uplink) refers to the communication link from the mobile devices to the access points. Further, communications between mobile devices and access points can be established via single-input single-output (SISO) systems, multiple-input single-output (MISO) systems, multiple-input multiple-output (MIMO) systems, and so forth. Further, in a peer-to-peer wireless network configuration, a mobile device can communicate with other mobile devices (and/or access points with other access points).

To supplement conventional base stations, additional restricted access points may be deployed to provide more robust wireless coverage for mobile devices. For example, wireless relay stations and low power base stations (e.g., which may be commonly referred to as home nodebs or home enbs (collectively referred to as h (e) NBs), femto access points, femtocells, picocells, macrocells, etc.) may be deployed for increased capacity growth, richer user experience, in-building or other particular geographic coverage, and so forth. In some configurations, these low power base stations may be connected to the internet via a broadband connection (e.g., a Digital Subscriber Line (DSL) router, cable or other modem, etc.), which may provide a backhaul link to the mobile operator network. Thus, these low power base stations may be deployed, for example, in a user's home to provide mobile network access to one or more devices via a broadband connection.

In this regard, in many cases, the deployment of these low power base stations is not planned and, therefore, the base stations and/or the mobile devices with which they communicate may cause interference to other low power base stations, macrocell base stations, or other devices in the vicinity. For low power base stations, there are interference mitigation mechanisms that set their transmission power to prevent or mitigate interference to other access points. However, devices served by a low power access point may still cause interference to other access points.

Disclosure of Invention

The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

In accordance with one or more embodiments and corresponding disclosure thereof, various aspects are described in connection with modifying parameters of a femtocell access point to mitigate interference to one or more other access points in the vicinity. For example, a rise-over-thermal (RoT) threshold can be set for a femtocell access point based at least in part on one or more parameters related to a macrocell in which the access point communicates to mitigate interference to the access point of the macrocell and/or access points of one or more other femtocells. In one example, the RoT threshold can be determined based at least in part on one or more pathloss measurements received from one or more devices in communication with the femtocell access point (e.g., pathloss to the femtocell access point, to one or more macrocell or other femtocell access points, etc.). Further, in another example, a femtocell access point can increase a noise floor to mitigate interference from one or more other access points or devices communicating therewith (e.g., based at least in part on detection of signal strength of one or more other access points, out-of-cell interference, etc.).

According to one example, a method for setting a RoT threshold for a femtocell access point is provided. The method includes receiving one or more parameters corresponding to one or more access points, and determining a RoT threshold for the femtocell access point based at least in part on the one or more parameters. The method also includes setting a RoT threshold at the femtocell access point.

In another aspect, an apparatus for setting a RoT threshold for a femtocell access point is provided. The apparatus includes at least one processor configured to receive one or more parameters corresponding to one or more access points and determine a RoT threshold for the femtocell access point based at least in part on the one or more parameters. The at least one processor is further configured to set a RoT threshold at the femtocell access point. The apparatus also includes a memory coupled to the at least one processor.

In another aspect, an apparatus for setting a RoT threshold for a femtocell access point is provided that includes means for receiving one or more parameters corresponding to one or more access points, and means for determining the RoT threshold for the femtocell access point based at least in part on the one or more parameters. The apparatus also includes means for setting a RoT threshold at the femtocell access point.

Moreover, in another aspect, a computer program product for setting a RoT threshold for a femtocell access point is provided, the computer program product comprising a computer-readable medium having code for causing at least one computer to receive one or more parameters corresponding to one or more access points, and code for causing the at least one computer to determine the RoT threshold for the femtocell access point based at least in part on the one or more parameters. The computer-readable medium further includes code for causing the at least one computer to set a RoT threshold at a femtocell access point.

Further, in an aspect, an apparatus for setting a RoT threshold for a femtocell access point is provided that includes parameter receiving means for receiving one or more parameters corresponding to one or more access points, and RoT threshold determining means for determining a RoT threshold for a femtocell access point based at least in part on the one or more parameters. The apparatus also includes RoT threshold setting means for setting a RoT threshold at the femtocell access point.

According to another example, a method for adjusting parameters of an access point based on a determination of interference is provided. The method includes detecting a strongest transmit power of one or more access points and determining whether the strongest transmit power exceeds a transmit power used at a femtocell access point. The method also includes adjusting the estimated noise floor of the femtocell access point based at least in part on whether the strongest transmit power exceeds the transmit power.

In another aspect, an apparatus for adjusting parameters of an access point based on a determination of interference is provided. The apparatus includes at least one processor configured to detect a strongest transmit power of one or more access points and determine whether the strongest transmit power exceeds a transmit power used at a femtocell access point. The at least one processor is further configured to adjust a noise floor of the femtocell access point based at least in part on whether the strongest transmit power exceeds the transmit power. The apparatus also includes a memory coupled to the at least one processor.

In another aspect, an apparatus for adjusting parameters of an access point based on a determination of interference is provided that includes means for detecting a strongest transmit power of one or more access points, and means for adjusting a noise floor of a femtocell access point based at least in part on a determination of whether the strongest transmit power exceeds a transmit power of the femtocell access point.

Further, in another aspect, a computer program product for adjusting parameters of an access point based on a determination of interference is provided, the computer program product comprising a computer-readable medium having code for causing at least one computer to detect a strongest transmit power of one or more access points, and code for causing the at least one computer to determine whether the strongest transmit power exceeds a transmit power used at a femtocell access point. The computer-readable medium further comprises code for causing the at least one computer to adjust a noise floor of the femtocell access point based at least in part on whether the strongest transmit power exceeds the transmit power.

Further, in an aspect, an apparatus for adjusting parameters of an access point based on a determination of interference is provided that includes interference determining means for detecting a strongest transmit power of one or more access points, and noise floor adjusting means for adjusting a noise floor of a femtocell access point based at least in part on a determination of whether the strongest transmit power exceeds a transmit power of the femtocell access point.

To the accomplishment of the foregoing and related ends, one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed and the described description is intended to include all such aspects and their equivalents.

Drawings

The disclosed aspects will hereinafter be described in conjunction with the appended drawings, provided to illustrate and not to limit the disclosed aspects, wherein like designations denote like elements, and in which:

fig. 1 is a block diagram of an example system that facilitates mitigating interference in a wireless network.

Fig. 2 is a block diagram of an example system that facilitates determining a rise-over-thermal (RoT) threshold for mitigating device interference to other access points.

Fig. 3 is a block diagram of an example system for requesting path loss measurements from one or more devices.

Fig. 4 is a block diagram of an exemplary system for adjusting a noise floor or other parameters of an access point.

Fig. 5 is a flow diagram of an aspect of an example method for determining a RoT threshold for an access point.

Fig. 6 is a flow diagram of an aspect of an example method of determining a RoT threshold based on transmit power.

Fig. 7 is a flow diagram of an aspect of an exemplary method for determining a RoT threshold using a path-loss difference CDF.

Fig. 8 is a flow diagram of an aspect of an exemplary method for adjusting a noise floor at an access point.

FIG. 9 is a flow diagram of an aspect of an exemplary method of enhancing an estimated noise floor of a device during soft handoff.

Fig. 10 is a block diagram of an example mobile device in accordance with various aspects described herein.

Fig. 11 is a block diagram of an example system that facilitates adjusting one or more parameters of an access point.

Fig. 12 is a block diagram of an example system that determines a RoT threshold for an access point.

Fig. 13 is a block diagram of an exemplary system that enhances an estimated noise floor of a device during soft handoff.

Fig. 14 is a block diagram of an example wireless communication system in accordance with various aspects presented herein.

Fig. 15 is a schematic diagram of an exemplary wireless network environment that can be deployed in conjunction with the various systems and methods described herein.

Fig. 16 illustrates an example wireless communication system configured to support multiple devices in which various aspects of the subject disclosure can be implemented.

Fig. 17 is a schematic diagram of an exemplary communication system that enables deployment of femto cells in a network environment.

FIG. 18 shows an example of an overlay having multiple defined tracking areas.

Detailed Description

Various aspects are now described with reference to the drawings. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more aspects. It may be evident, however, that such aspect(s) may be practiced without these specific details.

As further described herein, one or more parameters of a femto access point can be set or adjusted to mitigate interference to one or more other access points (e.g., potentially caused by devices communicating with the femto access point). For example, a threshold for rise-over-thermal (RoT) for a femtocell access point can be set and/or adjusted based on one or more parameters related to the access point in which the femtocell access point is communicating. In one example, the one or more parameters can be a path loss to a femtocell access point, one or more other femtocell access points, or a macrocell access point, among others. In another example, an estimated noise floor for an access point may be adjusted based on a determined level of interference caused to the access point. In either case, such adjustments may result in modification of the power used by devices with which they communicate, which may mitigate interference caused at or by one or more access points.

As used in this application, the terms "component," "module," "system," and the like are intended to include a computer-related entity, such as but not limited to hardware, firmware, a combination of hardware and software, or software in execution. For example, a component may be, but is not limited to being, a process running on a processor, an object, an executable, a thread of execution, a program, and/or a computer. By way of illustration, both an application running on a computing device and the computing device can be a component. One or more components can reside within a process and/or thread of execution and a component may be localized on one computer and/or distributed between two or more computers. In addition, these components can execute from various computer readable media having various data structures stored thereon. The components may communicate by way of local and/or remote processes such as in accordance with a signal having one or more data packets (e.g., data from one component interacting with another component in a local system, distributed system, or across a network such as the internet with other systems by way of the signal).

Moreover, various aspects are described herein in connection with a terminal (which can be a wired terminal or a wireless terminal). A terminal can also be called a system, device, subscriber unit, subscriber station, mobile device, remote station, remote terminal, access terminal, user terminal, communication device, user agent, user device, or User Equipment (UE). A wireless terminal may be a cellular telephone, a satellite telephone, a cordless telephone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a handheld device having wireless connection capability, a computing device, or other processing device connected to a wireless modem. Moreover, various aspects are described herein in connection with a base station. A base station may be utilized for communicating with wireless terminal(s) and may also be referred to as an access point, node B, evolved node B (enb), h (e) NB, or some other terminology.

Furthermore, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or". That is, unless specified otherwise or clear from context, the phrase "X employs A or B" is intended to mean any of the natural inclusive permutations. That is, any of the following examples satisfies the phrase "X employs A or B": x is A; b is used as X; or X uses both A and B. In addition, the articles "a" and "an" as used in this application and the appended claims should generally be construed to mean "one or more" unless specified otherwise or clear from context to be directed to a singular form.

The techniques described herein may be used for various wireless communication systems such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA and other systems. The terms "system" and "network" are often used interchangeably. A CDMA system may implement a radio technology such as Universal Terrestrial Radio Access (UTRA), CDMA2000, etc. UTRA includes wideband-CDMA (W-CDMA) and other variants of CDMA. Further, cdma2000 covers the IS-2000 standard, the IS-95 standard and the IS-856 standard. TDMA systems may implement wireless technologies such as global system for mobile communications (GSM). OFDMA systems may implement methods such as evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, flash-Etc. wireless technologies. UTRA and E-UTRA are part of the Universal Mobile Telecommunications System (UMTS). 3GPP Long Term Evolution (LTE) is a version of UMTS that uses E-UTRA, which uses OFDMA on the downlink and SC-FDMA on the uplink. UTRA, E-UTRA, UMTS, LTE, and GSM are described in documents from an organization entitled "third Generation partnership project" (3 GPP). Further, cdma2000 and UMB are described in documents from an organization named "third generation partnership project 2" (3 GPP 2). Further, such wireless communication systems may additionally include peer-to-peer (e.g., mobile-to-mobile) ad hoc network systems that typically use unpaired unlicensed spectrum, 802.xx wireless LANs, bluetooth, and any other short-range or long-range wireless communication technologies.

Various aspects or features will be presented in terms of systems that may include a number of devices, components, modules, and the like. It is to be understood and appreciated that the various systems may include additional devices, components, modules, etc. and/or may not include all of the devices, components, modules etc. discussed in connection with the figures. Combinations of these methods may also be used.

Referring to fig. 1, an exemplary wireless communication system 100 that facilitates setting one or more parameters at a serving access point to mitigate interference to other access points is illustrated. System 100 includes a device 102 that can communicate with a serving access point 104 to receive access to a wireless network and/or one or more components thereof. System 100 may also include other access points 106 and/or 108, and device 102 may potentially interfere with access points 106 and/or 108. The system 100 also optionally includes another device 110, which may be served by the serving access point 104. For example, devices 102 and/or 110 may be a UE, a modem (or other networked (connected) device) portion thereof, or the like. Each of access points 104, 106, and/or 108 may be a femtocell access point (such as a home nodeb or home evolved nodeb, collectively referred to herein as an h (e) NB), a picocell access point, a macrocell access point, a mobile base station, a relay node, a device (e.g., communicating in peer-to-peer or ad hoc mode), a portion thereof, and so forth.

According to an example, device 102 can potentially interfere with access points 106 and/or 108 while transmitting signal 112 to serving access point 104 (whether reporting path loss or otherwise). As described, at least some of serving access points 104, 106, and/or 108 may be part of a femtocell or other unplanned wireless network deployment, and thus, access points 104, 106, and/or 108 or devices in communication therewith may interfere with each other (e.g., where the access points are deployed in close proximity). In this regard, for example, the serving access point 104 can set or adjust one or more parameters to mitigate potential interference caused by the device 102 and/or other devices.

As further described herein, the serving access point 104 can set a RoT threshold based at least in part on one or more communication parameters to mitigate interference to the access points 106 and/or 108. In one example, the one or more communication parameters can correspond to pathloss measurements to access points 106 and/or 108 and pathloss to serving access point 104 as calculated by device 102, one or more other devices (e.g., device 110), a Network Listening Module (NLM) of the serving access point (not shown), and/or the like. The RoT threshold can be additionally set based at least in part on a determined noise floor, or the like, at the access point. Thus, for example, device 102 may report path loss measurement 112 to serving access point 104 based at least in part on a path loss to the serving access point (calculated based on signal 114), a path loss to access point 106 (calculated based on received signal 116), and/or the like. In another example, the one or more parameters may correspond to parameters that can be used to determine path loss, such as Received Signal Code Power (RSCP), Common Pilot Indicator Channel (CPICH) transmit power in LTE, and so on.

In another example, the serving access point and access point 106 (and/or access point 108) may use different transmission powers, which may result in device 102 communicating with access point 104, where access point 104 operates at a greater distance but transmits using a higher power than access point 106. In this example, when the device 102 communicates with the serving access point 104 at a higher power, the device 102 may thus interfere with the access point 106. To mitigate such interference, for example, the access point 106 can adjust the RoT threshold and/or the noise floor to increase the transmission power used by devices with which it communicates. In this example, the access point 106 can obtain the transmission power 118 of the serving access point 104 and/or other proximate access points (not shown) at least in part by using NLM or other devices, receiving an indication of power from the serving access point 104, and/or the like. The access point 106 may adjust the noise floor by the difference in transmission power between the access point 106 and the serving access point 104. In another example, access point 106 can adaptively adjust a noise floor or RoT threshold based at least in part on the difference.

In another example, the device 102 can communicate with the serving access point 104 and the access point 106 simultaneously (e.g., during a Soft Handoff (SHO)) such that the device 102 communicates control data with the serving access point 104 and receives user platform data from the access point 106 and/or the serving access point 104. In this example, where the access point 106 uses a higher transmit power than the serving access point 104, the serving access point 104 may not be able to reliably receive control data from the device 102 because the access point 106 may also control the power of the device 102 as part of the SHO. In this example, the access point 106 may enhance the adjusted noise floor during communication with the device 102 (e.g., rather than other devices that do not use SHO with the access point 106, such as a serving access point), which may cause the device 102 to increase transmission power, so the serving access point 104 may obtain control data therefrom. The above modifications allow managing interference caused by access points deployed in a wireless network.

Turning to fig. 2, an exemplary wireless communication system 200 for setting a RoT threshold at an access point is illustrated. System 200 includes a device 202, as described above, device 202 communicating with a serving access point 204 to receive access to one or more wireless network components. Further, system 200 can include another access point 206, because device 202 is in communication with serving access point 204, device 202 can potentially interfere with access point 206. For example, deployment of the serving access point may result in interference to other access points (not shown) in the vicinity of the serving access point 204, whether the interference is caused by the serving access point 204, the device 202, other devices in communication with the serving access point 204, or the like. As depicted, for example, the device 202 can be a UE, modem, etc., while the serving access point 204 can be a femtocell access point, h (e) NB, etc. As described, the access point 206 may be, for example, a macrocell access point, femtocell access point, or picocell access point, a mobile base station, a relay station, or the like.

Device 202 can optionally include a path loss measurement component 208 that determines path loss to one or more access points and a path loss reporting component 210 that sends the determined path loss to one or more access points or devices. Serving access point 204 includes parameter receiving component 212 for obtaining one or more parameters related to a communication environment (e.g., communicating in a macrocell), RoT threshold determining component 214 for determining a RoT threshold for the serving access point based at least in part on the one or more parameters, and RoT threshold setting component 216 for using the RoT threshold at the serving access point. Serving access point 204 may also optionally include NLM component 218 for obtaining and processing one or more signals from one or more access points and/or path-loss difference calculation component 220 for determining path-loss differences between serving access point 204 and one or more other access points.

According to an example, parameter receiving component 212 can obtain one or more parameters related to one or more other access points within range of serving access point 204 (e.g., access point 206 or one or more other femtocell access points, macrocell access points, or substantially any type of access point). For example, the parameters can correspond to one or more parameters related to a communication environment in proximity to access point 206, a location of access point 206 relative to serving access point 204, and/or the like. For example, RoT threshold determining component 214 can determine a RoT threshold for serving access point 204 based at least in part on the one or more parameters to mitigate interference to other access points (e.g., caused by devices communicating with serving access point 204). Further, a parameter measured within range of serving access point 204 or within range of serving access point 204 can refer to a signal from access point 206 that is listened to by serving access point 204, a device in communication with serving access point 204 (e.g., device 202), and/or the like.

For example, in the event that the RoT threshold for serving access point 204 is at a higher level, device 202 attempting to access serving access point 204 (e.g., attempting to access its Random Access Channel (RACH)) can increase transmission power to achieve a signal-to-noise ratio (SNR) corresponding to the RoT threshold. However, when the device 202 communicates with the serving access point 204 using the transmission power, this may cause interference to the access point 206. However, using a higher RoT threshold improves the throughput of the device 202 at the serving access point 204 and can improve resistance to interference from other devices communicating with other access points. Thus, RoT threshold determining component 214 can determine the RoT threshold for serving access point 204 using one or more parameters related to the communication environment of serving access point 204.

For example, where the one or more parameters include a location of the access point relative to serving access point 204 (e.g., and/or an absolute location of serving access point 204 as compared to an absolute location of access point 206), RoT threshold determination component 214 can estimate a distance between known locations of serving access point 204 and one or more other access points. For example, parameter receiving component 212 can receive the location of the one or more access points from an access point management server, such as a home eNB management server, a location server (not shown), such as a Serving Mobile Location Center (SMLC), access point 206, device 202, or other device, and/or the like. In this example, RoT threshold determining component 214 can calculate a distance to one or more access points (e.g., access point 206) based on the location of serving access point 204 (which can also be received from, for example, a location server) and the received locations of the one or more access points, and can determine a RoT threshold for serving access point 204 based on the calculated distance to mitigate interference to other access points. In one example, NLM component 218 can obtain a signal from access point 206 and can determine a signal strength; parameter receiving component 212 can obtain the signal strength from NLM component 218, and RoT threshold determining component 214 can additionally or alternatively determine a RoT threshold for serving access point 204 based on the signal strength to mitigate interference to access point 206.

In another example, device 202 can report path loss measurements to serving access point 204 to facilitate determining the RoT threshold. In this example, path loss measurement component 208 can measure path loss to serving access point 204, one or more neighboring access points (e.g., access point 206), and/or the like, and path loss reporting component 210 can send the path loss measurement to serving access point 204. Parameter receiving component 212 can obtain a path loss measurement value, and RoT threshold determining component 214 can determine a RoT threshold for serving access point 204 based at least in part on the path loss measurement value. For example, for a device 202 with which to communicate (e.g., attempting to access the RACH), the SNR at the serving access point 204 can be:

γ_RACH=TxPwr_F-PL_F-(RoT+No_F)

wherein, TxPwr_FIs the transmission power, PL, used by the device 202 to successfully access the serving access point 204_FIs the path loss to the serving access point 204 as measured by the device 202, RoT is the RoT at the serving access point 204, and No_FIs the noise floor at the serving access point 204. In one example, the noise floor may be predetermined and/or received in a configuration (e.g., from an access point management server, etc.).

Further, interference caused to an access point (e.g., access point 206) may be negligible so as not to affect access point 206 and/or devices communicating therewith:

TxPwr_F-PL_M<No_M-Δ_M

wherein PL_MIs the path loss, No, measured by the device 202 to the access point 206_MIs the noise floor of access point 206, and Δ_MIs the maximum interference level associated with the noise floor of the access point. Combining these equations yields:

RoT<(PL_M-PL_F)+(No_M-No_F)-γ_RACH-Δ_M

and the RoT threshold determining section 214 may calculate the upper limit of the RoT threshold by the following equation:

RoT_{bound_1}=Func1(PL_M-PL_F)+(No_M-No_F)-γ_RACH-Δ_M

wherein path loss measurement component 208 is coupled to PL_MAnd PL_FMeasurements are taken and path loss reporting component 210 reports PL_MAnd PL_FReported to serving access point 204, RoT threshold determination component 214 obtains No from access point management server and/or access point 206_MAnd No_FThe RoT threshold determining section 214 calculates γ as described above_RACHAnd obtains delta as a fixed value (e.g., from an access point management server or other core network component, configuration, etc.)_M. Further, Func1 may be PL_M-PL_FSuch as a minimum function, percentile distribution (e.g., 10%), etc., which may be configured by the RoT threshold determination component 214 (e.g., based on a hard-coded configuration, a configuration received from one or more network components, etc.).

In another example, where multiple access points are present in the vicinity of the serving access point 204 and potentially interfered, the upper limit of the RoT threshold can be determined as:

where k is an index of a corresponding access point (e.g., an access point of a macrocell, femtocell, picocell, etc.). In addition, however, the device 202 may access the serving access point 204 under the constraint of a maximum transmit power, which may be set by the serving access point 204:

γ_RACH<Max_TxPwr_F-PL_F-(RoT+No_F)

where Max TxPwr is the maximum transmit power, which may be received or otherwise determined by parameter receiving component 212. This may yield another upper limit for the RoT threshold that the RoT threshold determination component 214 may calculate:

RoT_{bound_2}=Max_TxPwr_F-Func2(PL_F)-γ_RACH-No_F

among them, Func2 (PL)_F) Is at a plurality of device locations PL_FA function of the statistics (e.g., a minimum function, percentile distribution, etc.). Thus, in one example, RoT threshold determining component 214 can calculate the RoT threshold for the serving access point by the following equation:

RoT_thres=min(RoT_{bound_1},RoT_{bound_2})

for example, the various path loss measurements discussed above can be performed periodically (e.g., based on one or more timers) by device 202 and/or NLM component 218 upon request from serving access point 204 (e.g., as part of a training period indicated by serving access point 204), and/or the like. As described, RoT threshold determination component 214 can receive path loss measurements and determine RoT thresholds accordingly. In one example, a needle may be calculated using a training period during which one or more devices report path loss measurementsFor PL_M，k-PL_F、PL_FStatistics of (d), etc. For example, upon initialization or otherwise (e.g., based on an event or other trigger), serving access point 204 can determine downlink transmit power based on parameters (e.g., received signal strength, broadcasted system information, etc.) detected by other access points in the vicinity (e.g., access point 206), and can determine a downlink coverage area based on these parameters accordingly. RoT threshold determination component 214 can also set an initial RoT threshold based on NLM component 218 that measures path loss to one or more access points as described above.

Next, in this example, serving access point 204 may enter a training period to request pathloss measurements from one or more devices (e.g., device 202) to one or more access points (e.g., access point 206). In one example, as described above, the NLM component 218 can have an identifier of the collected serving access point (e.g., Primary Scrambling Code (PSC)) when first measured to determine the downlink transmit power. Path-loss difference calculation component 220 may request path-loss measurements from devices (e.g., device 202) and may assign these identifiers to these devices accordingly. These devices (e.g., device 202) may use path loss measurement components (e.g., path loss measurement component 208) to measure path loss to one or more of the identified access points. Further, in the event that additional access points are encountered by path loss measurement component 208, path loss reporting component 210 can report the path loss to serving access point 204, and path loss difference calculation component 220 can add an identifier of the additional access points to the list of determined identifiers.

Once the path-loss measurements from these devices (e.g., device 202) to one or more access points (e.g., access point 206) are collected, path-loss difference computation component 220 may generate a path-loss difference report or cumulative density function (DCF) for each access point for which a path-loss measurement was received. For example, for service specific reporting by the deviceEach pathloss measurement PL for the entry point 204_FPath-loss difference calculating component 220 may calculate the kth path-loss sample PL to another access point reported by the device at the closest time_M，kPositioning is performed and the path loss difference PL is calculated_M，k-PL_F. Thus, path-loss difference calculation component 220 may calculate the PL for each report_FTo calculate a set of PLs_M，k-PL_FAnd a corresponding path loss difference CDF can be constructed. In another example, path-loss difference calculation component 220 can be based on PL reported during a training period_FThe CDFs are constructed by sampling. As described, the RoT threshold determining component 214 can use the path-loss difference CDF in determining the RoT threshold (e.g., by using the path-loss CDF in Func1 or Func2 shown above).

Referring to fig. 3, an exemplary wireless communication system 300 for generating a path-loss difference CDF is shown. System 300 includes a device 302 that communicates with an access point 304 to receive access to a wireless network. System 300 also includes access point 206 that can potentially interfere with access point 206 when device 302 transmits a signal to access point 304 (which can include interference to devices communicating with access point 206). In this regard, for example, access point 304 and/or access point 206 may be deployed in proximity to each other. As depicted, device 302 can be a UE, modem, etc., and access point 304 and/or access point 206 can be a macrocell access point, femtocell access point, or picocell access point, respectively.

The apparatus 302 can include a path loss measurement component 208 for determining path loss to one or more access points, a path loss reporting component 210 for sending path loss to one or more similar or disparate access points, and a measurement request receiving component 306 for obtaining a request from an access point to provide path loss measurements corresponding to one or more access points.

Access point 304 includes parameter receiving component 212 for obtaining one or more path loss measurements from a device to one or more access points, RoT threshold determining component 214 for determining a RoT threshold for access point 304 based at least in part on the one or more path loss measurements, and RoT threshold setting component 216 for using the RoT threshold at access point 304. Access point 304 can additionally include an optional co-located NLM component 218 for receiving signals from one or more access points for determining path loss to the access point, a path loss difference calculation component 220 for determining path loss differences between access point 304 and one or more other access points based on device measurements, and a measurement request component 308 for sending a request to one or more devices to perform one or more path loss measurements.

According to an example, the access point 304 can collect path loss statistics for calculating the RoT threshold, as described above. For example, path loss measurement component 208 can measure path losses to access point 304, one or more neighboring access points (e.g., access point 206), and/or the like, and path loss reporting component 210 can send these path loss measurements to access point 304. As described above, parameter receiving component 212 can obtain the pathloss measurements, and RoT threshold determining component 214 can determine a RoT threshold for access point 304 based at least in part on the pathloss measurements. Further, for example, measurement requesting component 308 can request device 302 and/or other devices to perform one or more path measurements to facilitate determining the RoT threshold.

In one example, the measurement request component 308 can determine a set of access points to monitor, and can calculate RoT thresholds for the set of access points to mitigate interference to the set of access points based on path losses from respective devices to the set of access points. For example, measurement request component 308 can employ NLM component 218 to scan a Primary Scrambling Code (PSC) range, or other access point identification range, to determine an access point and/or related cell (e.g., access point 206) from which signals NLM component 218 can receive.

In another example, measurement requesting component 308 can determine another operating frequency for one or more of the determined access points and can request that one or more devices perform inter-frequency measurements on the other operating frequency (e.g., in addition to or as an alternative to a designated original operating frequency for one or more of the determined access points) for the one or more determined access points. This may facilitate measurements for one or more of the determined access points in the event that one or more devices are unable to detect a signal from one or more of the determined access points on the original operating frequency (e.g., receive pilot transmit power below a threshold detected signal-to-interference ratio (SIR)). In one example, the measurement requesting component 308 can determine to request measurements on another operating frequency when measurements for one or more of the determined access points are not received within a given time period. Further, in one example, the another operating frequency can be close to an original operating frequency of one or more of the determined access points.

Once measurement requesting component 308 determines the set of access points and/or operating frequencies thereof, measurement requesting component 308 can configure one or more devices, such as device 302, to measure and report path loss to at least a portion of the access points (e.g., including access point 206) and access point 304 in the set as part of a training period. Measurement request receiving component 306 can obtain the request to measure path loss, and path loss measuring component 208 can accordingly receive signals from at least a portion of the set of access points and access point 304 and measure path loss based on the signals.

In this example, path loss reporting component 210 can send the measured path loss to one or more access points (including access point 304 and access point 206) to access point 304. It should be appreciated that the path loss measurement component 208 can measure path loss to additional access points with other PSCs and the path loss reporting component 210 can report the path loss, and the measurement request component 308 can add the additional PSC to the set of access points. As described above, parameter receiving component 212 may receive path loss measurements from device 302 and/or additional path loss measurements from other devices. In this aspect, path loss measurements for at least a portion of the set of access points may be received based on different device locations. The parameter receiving component 212 can construct a path loss Cumulative Density Function (CDF) or other combination of these path loss measurements for each access point in the set based at least in part on the received path loss measurements. Alternatively, parameter receiving component 212 can use NLM component 218 to characterize path loss to each access point in the set of access points based at least in part on the measurement signals from the access points.

Once the parameter receiving component 212 obtains a plurality of path loss measurements and determines the CDFs for the portion of access points, the parameter receiving component 212 may also calculate a difference CDF for each access point in the portion of access points for which path loss measurements are received. For example, for each pathloss measurement PL reported by a device, such as device 302, for access point 304_FParameter receiving component 212 may determine the pathloss PL to the i-th access point reported by the particular device at the closest time_M(i) In that respect For example, parameter receiving component 212 may estimate i pathloss measurements reported by the device to determine which pathloss measurement has the most recent time, where i is the number of access points in the group measured by the device. Parameter receiving component 212 can target each reported PL_FCalculating a difference PL of path loss measurements_M(i)-PL_FAnd the difference CDF can be constructed accordingly.

Alternatively, where parameter receiving component 212 characterizes path-loss differences using NLM component 218, parameter receiving component 212 can calculate a path using measured path-losses for access points in the set of access points obtained from NLM component 218 and an assumed path-loss for access point 304 (e.g., based on a 90 decibel (db) coverage radius of the downlink transmission power)And the path loss is poor. In any one example, RoT threshold determining component 214 can determine the RoT threshold for access point 304 based at least in part on the difference CDF or other calculated path loss difference to access points in the set of access points. For example, RoT threshold determining component 214 can be based at least in part on having the lowest pathloss measurement PL into the set of access points_M(i) Or path loss difference measurement PL_M(i)-PL_FTo determine the RoT threshold.

For example, the RoT threshold determining component 214 can determine the path loss thresholds for the set of access points based at least in part on a previously determined CDF or a difference CDF. For example, a path loss threshold may be determined based at least in part on one or more reported path loss differences in the CDFs. In one example, RoT threshold determination component 214 may determine the path loss threshold as a certain percentile distribution of path loss differences in the CDFs (e.g., the lowest reported difference value, n percent of the lowest reported difference value, etc.). In any case, the RoT threshold setting component 216 can use the RoT threshold for the access point 304, as described above.

Referring to fig. 4, an exemplary wireless communication system 400 that facilitates adjusting an access point noise floor or RoT threshold is illustrated. System 400 includes a device 402 that communicates with one or more access points 404 and/or 406 to access a wireless network. As described above, for example, the device 402 can potentially interfere with the access point 406 (which can include interference to devices communicating with the access point 406) while transmitting signals to the access point 404 and/or vice versa. In this regard, for example, access points 404 and/or 406 may be deployed in proximity to one another. As described above, the device 402 may be a UE, modem, etc., and each of the access points 404 and/or 406 may be a macrocell access point, a femtocell access point, or a picocell access point, etc.

Access point 404 can include an optional NLM component 408 for receiving signals from one or more access points and an interference determination component 410 for determining a level of interference potentially caused by the one or more access points (e.g., based at least in part on their transmission powers). The access point 404 can further optionally include a noise floor adjustment component 412 for adjusting a noise floor of the access point 404 based at least in part on the determined potential interference, a RoT threshold adjustment component 414 for adjusting a RoT threshold of the access point 404 based at least in part on the determined potential interference, and/or a SHO device request component 416 for requesting a list of identifiers of one or more devices for which the one or more access points provide SHO access.

According to an example, access point 404 can transmit at a different power than access point 406. For example, where the access point 406 is serving the device 402 and transmitting at a higher power, the device 402 may be physically closer to the access point 404, but may still be communicating with the access point 406 due to the higher transmission power. This may cause interference to the access point 404. In one example, as part of initialization of the access point 404 or based on one or more events or other triggers (e.g., a timer, detection of the presence of a new access point, etc.), the interference determination component 410 can resolve potential interference that may be caused by one or more neighboring access points (e.g., access point 406) and can adjust one or more parameters of the access point 404 to mitigate the potential interference.

In one example, access point 404 can obtain pilot transmission power for access point 406 and/or one or more other neighboring access points. For example, NLM component 408 may detect a signal from one or more nearby access points (e.g., access point 406) and may determine its downlink pilot transmission power based at least in part on measurements made on the signal, processing of data represented in the signal, and/or the like. In another example, interference determining component 410 can receive downlink pilot transmission power of one or more neighboring access points from an access point management server or other core network component, or the like. In any case, interference determining component 410 can accordingly determine the presence and/or total amount of potential interference from the one or more access points. In one example, interference determining component 410 can determine this based on comparing the downlink transmission power to a downlink transmission power of access point 404.

For example, based on the determined likely interference, the noise floor adjustment component 412 can adjust the noise floor of the access point 404. In one example, interference determining component 410 can determine the strongest downlink pilot transmission power received or observed by NLM component 408 (e.g., in the case of a single or multiple neighboring access points). The noise floor adjustment component 412 may adjust the noise floor according to the following formula, for example:

XdB=max(0,Own_Pilot_TxPwr-Strongest_Pilot_TxPw r)

where Own _ Pilot _ TxPwr is the transmission power of the access point 404, and Strongest _ Pilot _ TxPwr is the transmission power of the Strongest neighboring access point (e.g., access point 406). For example, by raising the noise floor of the access point 404, devices communicating with it can increase transmission power to suppress the impact of interference on the access point 404. In this regard, for example, the access point 404 can enhance the adjusted noise floor during communication with one or more devices (e.g., in power control commands to the one or more devices based on received power). For example, the noise floor adjustment component 412 can adjust the uplink power control algorithm to perform the pilot SNR calculation by adding the virtual noise power to the estimated interference and noise power. Additionally, for example, one or more devices may inject additional noise, adjust RF front end attenuators, and the like based on the adjustment of the noise floor.

In another example, the noise floor adjustment component 412 can adaptively adjust the noise floor of the access point 404 based on an estimated level of out-of-cell interference (e.g., based on interference received from the device 402 while communicating with the access point 406). For example, interference determining component 410 can measure or estimate a level of interference to access point 404, which can include measuring a noise level during a silent time interval or other period (e.g., using NLM component 408), measuring a transmitted signal received by NLM component 408, and determining a noise level on the signal based on a power used to transmit the signal from access point 404, and so forth. In any case, for example, the noise floor adjustment component 412 can adaptively adjust the noise floor according to an equation similar to the following equation:

YdB=max(0,min(XdB,Out_of_Cell_Intf_dB+Margin_dB))

where Out of Cell Intf dB is the measured or estimated Out-of-Cell interference level and Margin dB is a constant value that makes Out-of-Cell interference negligible based on the increased noise floor. Thus, for the case where the estimated out-of-cell interference is 0, the noise floor will not be increased to prevent the transmit power of the device from being unnecessarily increased due to the increase in the noise floor.

In another example, rather than or in addition to adjusting the noise floor, RoT threshold adjustment component 414 can adjust the RoT threshold for access point 404 as a function of potential or actual interference or one or more access points determined by interference determination component 410. In one example, as indicated above, the RoT threshold adjustment component 414 can adjust the RoT threshold for the access point 404 based at least in part on the calculated XdB. For example, the RoT threshold adjustment component 414 can calculate the adjustment of the RoT threshold based on the following equation or a similar equation:

so that the RoT threshold corresponds to x db according to a function, which in this example may be linear, but other kinds of functions may be used as well in this respect. Similarly, as described in one example, the RoT threshold adjusting component 414 can adjust the RoT threshold in the event the interference determining component 410 detects out-of-cell interference. Further, the RoT threshold adjusting component 414 can similarly limit interference to other access points in the vicinity in accordance with the upper limit of the calculated RoT threshold as described in fig. 2.

In another example, device 402 can be served by access point 406 and can also communicate user platform data with access point 404 (e.g., and access point 406) during SHO. In this example, access points 404 and 406 may each control the uplink transmission power of device 402 (e.g., by sending power adjustment commands to device 402). In some examples, the access point 404 may turn the transmission power of the device 402 down while the access point 406 attempts to increase the transmission power of the device 402, such as where the device 402 is closer to the access point 406 but the path loss to the access point 404 is smaller. In this example, the noise floor adjustment component 412 can adjust the estimated noise floor for use in adjusting a power algorithm for devices not served by the access point 404 during SHO. Thus, for example, the SHO device request component 416 can request a list of identifiers from one or more access points (e.g., access point 406) corresponding to devices served by the one or more access points during SHO.

In this example, noise floor adjustment component 412 can calculate a noise floor adjustment based at least in part on the actual or potential interference determined by interference determination component 410. Noise floor adjustment component 412 can then identify devices served by access point 406 or one or more other access points that communicate with access point 404 during SHO based on the received device identifiers, and can adjust uplink power allocations to such devices (e.g., device 402) based at least in part on the calculated noise floor. Thus, transmitting an increase in the noise floor of the access point 404 to the device 402 may cause the device 402 to increase transmit power, which may improve the control channel quality between the device 402 and the access point 406. In this example, the noise floor adjustment component 412 can refrain from sending adjustments to the noise floor to devices served by the access point 404 to mitigate interference to the access point 406 or other access points potentially caused by these devices.

Referring to fig. 5-9, exemplary methodologies relating to adjusting one or more parameters of a femtocell access point to mitigate interference are illustrated. While, for purposes of simplicity of explanation, the methodologies are shown and described as a series of acts, it is to be understood and appreciated that the methodologies are not limited by the order of acts, as some acts may, in accordance with one or more embodiments, occur in different orders and/or concurrently with other acts from that shown and described herein. For example, it will be appreciated that a methodology could alternatively be represented as a series of interrelated states or events, such as in a state diagram. Moreover, not all illustrated acts may be required to implement a methodology in accordance with one or more embodiments.

Referring to fig. 5, an exemplary methodology 500 that facilitates determining a RoT threshold is illustrated. At 502, one or more parameters correspond to one or more access points. For example, the one or more parameters may correspond to wireless conditions of the one or more access points (e.g., path loss to the one or more access points), locations of the one or more access points relative to the femtocell access point, and/or the like. Further, in one example, the one or more parameters may thus be received (e.g., based on a request for measurements as part of a training period) from the NLM, the one or more devices, and/or the like. Further, for example, the one or more parameters can relate to maximum transmit power, path loss statistics, etc., as described above, and the RoT threshold can be determined therefrom. At 504, a RoT threshold for the femtocell access point can be determined based at least in part on the one or more parameters. At 506, a RoT threshold can be set at the femtocell access point. This may, for example, cause one or more devices to adjust a transmit power used to communicate with the femtocell access point.

Turning to fig. 6, an exemplary method 600 of determining a RoT threshold for a femtocell access point is illustrated. At 602, one or more path loss measurements for one or more access points can be received. As described above, this may be based on a request for measurements (e.g., as part of a training period or otherwise). Further, the path loss measurement may be received from a device, a NLM located at the same location in the access point, or the like. At 604, a maximum transmit power supplied to one or more devices may be obtained. This may be determined, for example, by the component or components supplying the maximum transmit power. At 606, a RoT threshold can be determined based at least in part on the one or more path loss measurements and the maximum transmit power. As described above, the RoT threshold may be calculated for each of the path loss measurement value and the maximum transmission power, and the minimum of the two may be set as the RoT threshold.

Referring to fig. 7, an exemplary method 700 for determining a RoT threshold is shown. At 702, one or more devices may be configured to measure and report path loss to at least a portion of a set of one or more access points. For example, as described above, a set of access points can be determined (e.g., by receiving a list of one or more access points from a network component, device, etc., by detecting the one or more access points via NLM, etc.). In this example, where one or more devices are capable of receiving signals from the set of access points, a request can be sent to the one or more devices to measure path losses for the set of access points. At 704, pathloss measurements from the one or more devices to the portion of the set of one or more access points can be received. For example, as described above, this may include receiving a power measurement or other measurement that may determine a path loss or similar parameter (e.g., RSCP, CPICH transmit power, etc.). At 706, a path-loss difference, CDF, for at least the portion of the one or more sets of access points can be constructed based on the received path-loss measurements. As described above, this may include determining a received path loss measurement for one or more access points of the set of access points and subtracting another path loss therefrom. At 708, a RoT threshold is determined based at least in part on the path-loss difference, CDF, as described above.

Turning to fig. 8, an example methodology 800 is illustrated for adjusting one or more parameters of an access point to mitigate interference. At 802, the strongest transmit power of one or more access points can be detected. This may include, for example, receiving signals from one or more access points in the vicinity (e.g., using NLM and/or from one or more devices), and determining which access point has the strongest signal power. At 804, it may be determined whether the strongest transmit power exceeds the transmit power used at the femtocell access point. At 806, at least an estimated noise floor of the femtocell access point can be adjusted based at least in part on whether the strongest transmit power exceeds the transmit power. In one example, the estimated noise floor may be adjusted by the amount by which the strongest transmit power exceeds the transmit power. In another example, the estimated noise floor may be adjusted additionally based on the out-of-cell interference. Further, the RoT threshold can also be adjusted based on whether the strongest transmit power exceeds the transmit power, for example.

Referring to fig. 9, an exemplary methodology 900 that facilitates enhancing noise floor increase on one or more devices is illustrated. At 902, identifiers of one or more devices served by one or more access points during a SHO can be received. This may be based at least in part on a request for these parameters, for example. At 904, a noise floor that increases the estimate may be determined. This may be based, at least in part, on detecting a stronger transmission power at the access point than the transmission power used, for example. Further, the estimated noise floor may be specific to one or more devices. At 906, an increase in the estimated noise floor may be enhanced in communicating with one or more devices. In this regard, as described above, the noise floor is not increased and enhanced on the served devices, but is instead directed to devices served by other access points that communicate using SHO.

It should be appreciated that, as described above, inferences can be made regarding calculating the RoT threshold, noise floor adjustment, and so forth, in accordance with one or more aspects described herein. As used herein, the term to "infer" or "inference" refer generally to the process of reasoning about or inferring states of the system, environment, and/or user from a set of observations as captured via events and/or data. Inference can be employed to identify a specific context or action, or can generate a probability distribution over states, for example. Such inference can be probabilistic-that is, the computation of a probability distribution over states of interest based on a consideration of data and events. Inference can also refer to techniques employed for composing higher-level events from a set of events and/or data. Such inference results in the construction of new events or actions from a set of observed events and/or stored event data, whether or not the events are correlated in close temporal proximity, and whether the events and data come from one or several event and data sources.

Fig. 10 is an illustration of a mobile device 1000 that facilitates reporting of pathloss measurements. Mobile device 1000 includes a receiver 1002, receiver 1002 that receives a signal from, for instance, a receive antenna (not shown), performs typical operations on (e.g., filters, amplifies, downconverts, etc.) the received signal, and digitizes the conditioned signal to obtain samples. Receiver 1002 can comprise a demodulator 1004 that can demodulate received symbols and provide them to a processor 1006 for channel estimation. Processor 1006 can be a processor dedicated to analyzing information received by receiver 1002 and/or generating information for transmission by a transmitter 1008, a processor that controls one or more components of mobile device 1000, and/or a processor that both analyzes information received by receiver 1002, generates information for transmission by transmitter 1008, and controls one or more components of mobile device 1000.

Mobile device 1000 may additionally comprise memory 1010, memory 1010 operatively coupled to processor 1006 and that may store data to be transmitted, received data, information related to available channels, data associated with analyzed signal and/or interference strength, information related to an assigned channel, power, rate, or the like, any other suitable information for estimating a channel and communicating via the channel, and the like. Memory 1010 may additionally store protocols and/or algorithms associated with estimating and/or using a channel (e.g., performance based, capacity based, etc.), reporting path loss, etc.

It will be appreciated that the data store (e.g., memory 1010) described herein can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory. By way of example, and not limitation, nonvolatile memory can include Read Only Memory (ROM), Programmable ROM (PROM), Electrically Programmable ROM (EPROM), Electrically Erasable PROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM), which acts as external cache memory. By way of example and not limitation, RAM is available in a variety of forms such as Synchronous RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), Enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), and Direct Rambus RAM (DRRAM). The memory 1010 of the subject systems and methods is intended to comprise, without being limited to, these and any other suitable types of memory.

The processor 1006 may also be selectively operably coupled to a path loss measurement component 1012, which may be similar to the path loss measurement component 208, a path loss reporting component 1014, which may be similar to the path loss reporting component 210, and a measurement request receiving component 1016, which may be similar to the measurement request component 306. The mobile device 1000 also includes a demodulator 1018, the demodulator 1018 demodulating signals for transmission by the transmitter 1008 to, for instance, a base station, another mobile device, etc. Further, for example, as described above, the mobile device 1000 can include multiple transmitters 1008 for multiple network interfaces. Although path loss measurement component 1012, path loss reporting component 1014, measurement request receiving component 1016, demodulator 1004, and/or modulator 1018 are depicted as being separate from processor 1006, it is to be appreciated that they may be part of processor 1006 or multiple processors (not shown).

Fig. 11 is an illustration of a system 1100 that facilitates communicating with one or more devices using wireless communication. System 1100 includes a base station 1102, which can be substantially any base station (e.g., a small base station such as a femtocell, picocell, etc., a mobile base station, etc.), relay station, etc., base station 1102 having a receiver 1110 and a transmitter 1140, where receiver 1110 receives signals from one or more mobile devices 1104 via a plurality of receive antennas 1106 (e.g., which can have a variety of network technologies as described above) and transmitter 1140 transmits to one or more mobile devices 1104 via a plurality of transmit antennas 1108 (e.g., which can have a variety of network technologies as described above). Further, in one example, the transmitter 1140 can transmit to the mobile device 1104 over a wired forward link. Receiver 1110 can receive information from one or more receive antennas 1106 and is operatively associated with a demodulator 1112 that demodulates received information. Further, in one example, receiver 1110 can receive from a wired backhaul link. Demodulated symbols can be analyzed by a processor 1114, which processor 1114 can be similar to the processor described above with reference to fig. 10 and coupled to a memory 1116, which memory 1116 stores information related to estimating signal (e.g., pilot) strength and/or interference strength, data to be transmitted to or received from mobile device 1104 (or a disparate base station (not shown)), and/or any other suitable information related to performing the various operations or functions presented herein.

The processor 1114 is also selectively coupled to a parameter receiving component 1118 that can be similar to the parameter receiving component 212, a RoT threshold determining component 1120 that can be similar to the RoT threshold determining component 214, a RoT threshold setting component 1122 that can be similar to the RoT threshold setting component 216, an NLM component 1124 that can be similar to the NLM component 218 and/or 408, a path loss difference component 1126 that can be similar to the path loss difference computing component 220, and/or a measurement requesting component 1128 that can be similar to the measurement requesting component 308. Further, for example, the processor 1114 can also be selectively coupled to an interference determination component 1130 that can be similar to the interference determination component 410, a noise floor adjustment component 1132 that can be similar to the noise floor adjustment component 412, a RoT threshold adjustment component 1134 that can be similar to the RoT threshold adjustment component 414, and/or a SHO device request component 1136 that can be similar to the SHO device request component 416.

Further, processor 1114 can modulate signals for transmission using modulator 1138 and transmit the modulated signals using transmitter 1140, for example. Transmitter 1140 may transmit signals through Tx antenna 1108 to mobile device 1104. Further, while parameter receiving component 1118, RoT threshold determining component 1120, RoT threshold setting component 1122, NLM component 1124, path loss difference calculating component 1126, measurement requesting component 1128, interference determining component 1130, noise floor adjusting component 1132, RoT threshold adjusting component 1134, SHO device requesting component 1136, demodulator 1112, and/or modulator 1138 are depicted as being separate from processor 1114, it will be appreciated that they may be part of processor 1114 or multiple processors (not shown) and/or stored as instructions in memory 1116 for execution by processor 1114.

Referring to fig. 12, a system 1200 that determines a RoT threshold is illustrated. For example, system 1200 can reside at least partially within an access point or the like. It is to be appreciated that system 1200 is represented as including functional blocks, which can be functional blocks that represent functions implemented by a processor, software, or combination thereof (e.g., firmware). System 1200 includes a logical grouping 1202 of electrical components that can act in conjunction. For instance, logical grouping 1202 can include an electrical component for receiving one or more parameters corresponding to one or more access points 1204. As described above, the one or more parameters may correspond to, for example, path loss measurements to the one or more access points, locations of the one or more access points (e.g., absolute locations or locations relative to a femtocell access point or other reference point), and so forth.

Moreover, logical grouping 1202 can include an electrical component for determining a RoT threshold for a femtocell access point based at least in part on one or more parameters 1206. For example, as described above, the RoT threshold can be determined to suppress interference to one or more devices. Moreover, logical grouping 1202 can include an electrical component for setting a RoT threshold at the femtocell access point 1208. As described above, this may result in a device communicating with the femtocell access point reducing transmission power, which may suppress interference caused to one or more other access points, for example. In one example, as described above, electrical component 1204 may include parameter receiving component 212. As described above, for example, the electrical component 1206 can include the RoT threshold determination component 214. Further, as described above, for example, in one aspect, the electrical components 1208 can include the RoT threshold setting component 216.

Additionally, system 1200 can include a memory 1210 that retains instructions for executing functions associated with electrical components 1204, 1206, and 1208. While shown as being external to memory 1210, it is to be understood that one or more of electrical components 1204, 1206 and 1208 may exist within memory 1210. In one example, electrical components 1204, 1206, and 1208 can include at least one processor, or each of electrical components 1204, 1206, and 1208 can be a respective module of the at least one processor. Further, in additional or alternative examples, electrical components 1204, 1206, and 1208 can be a computer program product comprising a computer-readable medium, wherein each of electrical components 1204, 1206, and 1208 can be respective code.

Referring to fig. 13, illustrated is a system 1300 that adjusts one or more parameters of a femtocell access point to mitigate interference. For example, system 1300 may reside at least partially within a device, etc. It is to be appreciated that system 1300 is represented as including functional blocks, which can be functional blocks that represent functions implemented by a processor, software, or combination thereof (e.g., firmware). System 1300 includes a logical grouping 1302 of electrical components that can act in conjunction. For instance, logical grouping 1302 can include an electrical component for detecting a strongest transmit power of one or more access points 1304. As described above, this may include, for example, receiving signals from one or more neighboring access points and determining the strongest of the signals.

Moreover, logical grouping 1302 can comprise an electrical component for adjusting an estimated noise floor for a femtocell access point based at least in part on the determination of whether the strongest transmit power exceeds a transmit power of the femtocell access point 1306. As described above, for example, electronic component 1306 may set the noise floor to the difference in these transmit powers. As described above, for example, electrical component 1304 can include interference determination component 410. Further, for example, in one aspect, as described above, electronic component 1306 may include noise floor adjustment component 412.

Additionally, system 1300 can include a memory 1308 that retains instructions for executing functions associated with electrical components 1304 and 1306. While shown as being external to memory 1308, it is to be understood that one or more of electrical components 1304 and 1306 may exist within memory 1308. In one example, electrical components 1304 and 1306 can include at least one processor, or electrical components 1304 and 1306 can each be a respective module of the at least one processor. Further, in additional or alternative examples, electrical components 1304 and 1306 can be a computer program product comprising a computer-readable medium, wherein each of electrical components 1304 and 1306 can be respective code.

Referring now to fig. 14, a wireless communication system 1400 is illustrated in accordance with various embodiments presented herein. System 1400 includes a base station 1402, which base station 1402 can comprise multiple antenna groups. For example, one antenna group can include antennas 1404 and 1406, another can include antennas 1408 and 1410, and an additional can include antennas 1412 and 1414. Two antennas are shown for each antenna group; however, more or fewer antennas may be utilized for each antenna group. It is to be appreciated that base station 1402 can additionally include a transmitter chain and a receiver chain, each of which can in turn comprise a plurality of components associated with signal transmission and reception (e.g., processors, modulators, multiplexers, demodulators, demultiplexers, antennas, etc.).

Base station 1402 can communicate with one or more mobile devices, such as mobile device 1416 and mobile device 1422; however, it is to be appreciated that base station 1402 can communicate with substantially any number of mobile devices similar to mobile devices 1416 and 1422. The mobile devices 1416 and 1422 can be, for example, cellular phones, smart phones, laptops, handheld communication devices, handheld computing devices, satellite radios, global positioning systems, PDAs, and/or any other suitable device for communicating over the wireless communication system 1400. As described above, the mobile device 1416 is in communication with the antennas 1412 and 1414, where the antennas 1412 and 1414 transmit information to the mobile device 1416 over the forward link 1418 and receive information from the mobile device 1416 over the reverse link 1420. Moreover, mobile device 1422 is in communication with antennas 1404 and 1406, where antennas 1404 and 1406 transmit information to mobile device 1422 over forward link 1424 and receive information from mobile device 1422 over reverse link 1426. In a Frequency Division Duplex (FDD) system, forward link 1418 can utilize a different frequency band than that used by reverse link 1420, and forward link 1424 can employ a different frequency band than that employed by reverse link 1426, for example. Further, in a Time Division Duplex (TDD) system, forward link 1418 and reverse link 1420 can utilize a common frequency band and forward link 1424 and reverse link 1426 can utilize a common frequency band.

Each group of antennas and/or the area in which they are designated to communicate can be referred to as a sector of base station 1402. For example, antenna groups can be designed to communicate to mobile devices in a sector of the areas covered by base station 1402. When communicating over forward links 1418 and 1424, the transmitting antennas of base station 1402 can utilize beamforming to improve signal-to-noise ratio of forward links 1418 and 1424 for mobile devices 1416 and 1422. Moreover, mobile devices in neighboring cells can experience less interference when base station 1402 transmits using beamforming to mobile devices 1416 and 1422 scattered randomly through an associated coverage area as compared to a base station transmitting through a single antenna to all its mobile devices. In addition, the mobile devices 1416 and 1422 can communicate directly with one another using peer-to-peer or ad hoc technologies as described. According to one example, system 1400 can be a multiple-input multiple-output (MIMO) communication system. Further, as described above, base station 1402 can set a RoT threshold, a noise floor, or other parameters to avoid interference to other access points (not shown) based on one or more pathloss measurements to one or more access points, detected out-of-cell interference, and/or the like, for example.

Fig. 15 illustrates an exemplary wireless communication system 1500. The wireless communication system 1500 depicts one base station 1510 and one mobile device 1550 for sake of brevity. However, it is to be appreciated that system 1500 can include more than one base station and/or more than one mobile device, wherein additional base stations and/or mobile devices can be substantially similar or different from example base station 1510 and mobile device 1550, as described below. Moreover, it is to be appreciated that base station 1510 and/or mobile device 1550 can employ the systems (fig. 1-4 and 11-14), mobile devices (fig. 10), and/or methods (fig. 5-9) described herein to facilitate wireless communication there between. For example, components or functions of systems and/or methods described herein may be part of memory 1532 and/or 1572 or processor 1530 and/or 1570 as described below and/or may be executed by processor 1530 and/or 1570 to perform the disclosed functions.

At base station 1510, traffic data for a number of data streams is provided from a data source 1512 to a Transmit (TX) data processor 1514. According to one example, each data stream can be transmitted over a respective antenna. TX data processor 1514 formats, codes, and interleaves the traffic data stream based on a particular coding scheme selected for that data stream to provide coded data.

The coded data for each data stream can be multiplexed with pilot data using Orthogonal Frequency Division Multiplexing (OFDM) techniques. Additionally or alternatively, the pilot symbols may be Frequency Division Multiplexed (FDM), Time Division Multiplexed (TDM), or Code Division Multiplexed (CDM). The pilot data is typically a known data pattern that is processed in a known manner and can be used at mobile device 1550 to estimate the channel response. The multiplexed pilot and coded data for each data stream can be modulated (e.g., symbol mapped) based on a particular modulation scheme (e.g., binary phase-shift keying (BPSK), quadrature phase-shift keying (QPSK), M-phase-shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM), etc.) selected for that data stream to provide modulation symbols. The data rate, coding, and modulation for each data stream can be determined by instructions performed or provided by processor 1530.

The modulation symbols for the data streams can be provided to a TX MIMO processor 1520, which can further process the modulation symbols (e.g., for OFDM). Then, the TX MIMO processor 1520 combines N_TOne modulation symbol stream is provided to N_TA transmitter (TMTR) 1522a through 1522 t. In various embodiments, TX MIMO processor 1520 applies beamforming weights to the symbols of the data streams and to the antenna from which the symbol is being transmitted.

Each transmitter 1522 receives and processes a respective symbol stream to provide one or more analog signals, and further conditions (e.g., amplifies, filters, and upconverts) the analog signals to provide a modulated signal suitable for transmission over the MIMO channel. In addition, from N respectively_TN from transmitters 1522a through 1522t are transmitted by antennas 1524a through 1524t_TA modulated signal.

At mobile device 1550, N_RThe antennas 1552a through 1552r receive the transmitted modulated signals and provide the received signal from each antenna 1552 to a respective antennaReceivers (RCVR) 1554a through 1554 r. Each receiver 1554 conditions (e.g., filters, amplifies, and downconverts) a respective signal, digitizes the conditioned signal to provide samples, and further processes the samples to provide a corresponding "received" symbol stream.

RX data processor 1560 can be selected from N_RN is received at receiver 1554_RA stream of symbols and a receiver processing technique for the received N_RThe symbol streams are processed to provide N_TA "detected" symbol stream. RX data processor 1560 can demodulate, deinterleave, and decode each detected symbol stream to recover the traffic data for the data stream. The processing by RX data processor 1560 is complementary to that performed by TX MIMO processor 1520 and TX data processor 1514 at base station 1510.

The reverse link message may comprise various types of information regarding the communication link and/or the received data stream. The reverse link message can be processed by a TX data processor 1538, modulated by a modulator 1580, conditioned by transmitters 1554a through 1554r, and transmitted back to base station 1510, where TX data processor 1538 also receives traffic data for a number of data streams from a data source 1536.

At base station 1510, the modulated signals from mobile device 1550 are received by antennas 1524, conditioned by receivers 1522, demodulated by a demodulator 1540, and processed by a RX data processor 1542 to extract the reverse link message transmitted by mobile device 1550. Further, processor 1530 can process the extracted message to determine which precoding matrix to use for determining the beamforming weights.

Processors 1530 and 1570 can direct (e.g., control, regulate, manage, etc.) operation at base station 1510 and mobile device 1550, respectively. Respective processors 1530 and 870 can be associated with memory 1532 and 1572 that store program codes and data. Processors 1530 and 1570 can determine RoT thresholds, noise floor adjustments, path loss measurements, and the like, as described above.

Fig. 16 illustrates a wireless communication system 1600 configured to support multiple users, in which system 1600 the teachings herein may be implemented. System 1600 provides communication to a plurality of cells 1602 (e.g., macro cells 1602A-1602G), each of which is served by a respective access node 1604 (e.g., access nodes 1604A-1604G). As shown in fig. 16, access terminals 1606 (e.g., access terminals 1606A-1606L) can be distributed at various locations throughout the system over time. Each access terminal 1606 can communicate with one or more access nodes 1604 on a Forward Link (FL) and/or a Reverse Link (RL) at a given moment, depending on, for example, whether the access terminal 1606 is active and whether the access terminal is in a soft handoff state. The wireless communication system 1600 may provide service over a larger geographic area.

Fig. 17 illustrates an example communication system 1700 in which one or more femto nodes are deployed in a network environment. In particular, the system 1700 includes multiple femto nodes 1710A and 1710B (e.g., femto nodes or h (e) NBs) installed in a relatively small scale network environment (e.g., in one or more user residences 1730). Each femto node 1710 can be coupled to a wide area network 1740 (e.g., the internet) and a mobile operator core network 1750 via a Digital Subscriber Line (DSL) router, a cable modem, a wireless link, or other connection means (not shown). As discussed below, each femto node 1710 can be configured to serve associated access terminals 1720 (e.g., access terminal 1720A) and, optionally, alien access terminals 1720 (e.g., access terminal 1720B). In other words, access to the femto nodes 1710 can be restricted such that a given access terminal 1720 can be served by a set of designated (e.g., home) femto nodes 1710 and not by any non-designated femto nodes 1710 (e.g., neighbor's femto nodes).

Fig. 18 shows an example of an overlay 1800 in which several tracking areas 1802 (or routing areas or location areas) are defined, wherein each tracking area comprises several macro coverage areas 1804. Here, the coverage areas associated with the tracking areas 1802A, 1802B, and 1802C are depicted by thick lines, while the macro coverage areas 1804 are represented by hexagons. The tracking area 1802 also includes a femto coverage area 1806. In this example, each of the femto coverage areas 1806 (e.g., femto coverage area 1806C) is depicted within a macro coverage area 1804 (e.g., macro coverage area 1804B). It should be appreciated, however, that femto coverage area 1806 may not be entirely within macro coverage area 1804. Indeed, multiple femto coverage areas 1806 may be defined within a given tracking area 1802 or macro coverage area 1804. Further, one or more pico coverage areas (not shown) may be defined within a given tracking area 1802 or macro coverage area 1804.

Referring again to fig. 17, the owner of the femto node 1710 may subscribe to mobile services, e.g., 3G mobile services provided through the mobile operator core network 1750. Further, access terminal 1720 can operate in both macro environments and smaller scale (e.g., residential) network environments. Thus, for example, depending on the current location of the access terminal 1720, the access terminal 1720 can be served by an access node 1760 or by any one of a set of femto nodes 1710 (e.g., femto nodes 1710A and 1710B located within a respective user residence 1730). For example, when the subscriber is not at home, he is served by a standard macro cell access node (e.g., node 1760), and when the subscriber is at home, he is served by a femto node (e.g., node 1710A). Here, it should be appreciated that the femto node 1710 can be backward compatible with existing access terminals 1720.

The femto nodes 1710 can be deployed on a single frequency or on multiple frequencies. Depending on the particular configuration, a single frequency or one or more of the multiple frequencies may overlap with one or more frequencies used by a macro cell access node (e.g., node 1760). In some aspects, an access terminal 1720 may be configured to connect to a preferred femto node (e.g., a home femto node of the access terminal 1720) whenever connection of the access terminal 1720 with the preferred femto node is possible. For example, an access terminal 1720 can communicate with a home femto node 1710 whenever the access terminal 1720 is located within the user's residence 1730.

In some aspects, if the access terminal 1720 is operating within the mobile operator core network 1750 but is not located on its most preferred network (e.g., as defined in a preferred roaming list), the access terminal 1720 may continue to search for the most preferred network (e.g., the femto node 1710) using Better System Reselection (BSR), which may include periodic scanning of available systems to determine whether better systems are currently available and subsequently attempting to associate with those preferred systems. In one example, the access terminal 1720 can limit a search for a particular frequency band and channel by using an acquisition table entry (e.g., in a preferred roaming list). For example, the search for the most preferred system may be repeated periodically. When a preferred femto node, such as the femto node 1710, is discovered, the access terminal 1720 selects the femto node 1710 for camping within its coverage area.

In some aspects, a femto node may be restricted. For example, a given femto node may only provide certain services to certain access terminals. In deployments with so-called restricted (or closed) association, a given access terminal may only be served by a macro cell mobile network and a set of predetermined femto nodes (e.g., femto nodes 1710 located in respective user residences 1730). In some implementations, a femto node can be restricted to not provide at least one of signaling, data access, registration, paging, or service to at least one access terminal.

In some aspects, a restricted femto node (also referred to as a closed subscriber group h (e) NB) is a femto node that provides service to a set of access terminals that are restricted in settings. The set of access terminals may be temporarily or permanently extended if necessary. In some aspects, a Closed Subscriber Group (CSG) may be defined as a set of access nodes (e.g., femto nodes) that share a common access control list of access terminals. The channel on which all femto nodes (or all restricted femto nodes) in the area operate may be referred to as a femto channel.

Thus, various relationships can exist between a given femto node and a given access terminal. For example, from the perspective of an access terminal, an open femto node may refer to a femto node with unrestricted association. A restricted femto node may refer to a femto node that is restricted in some manner (e.g., restricted for association and/or registration). A home femto node may refer to a femto node on which an access terminal is authorized to access and operate. A customer femto node may refer to a femto node on which an access terminal is temporarily authorized to access or operate. An alien femto node may refer to a femto node on which an access terminal is not authorized to access or operate except for a possible emergency (e.g., 911 call).

From the perspective of a restricted femto node, a home access terminal may refer to an access terminal that is authorized to access the restricted femto node. A customer access terminal may refer to an access terminal with temporary access to a restricted femto node. An alien access terminal may refer to an access terminal that is not allowed to access a restricted femto node except for possible emergency situations such as 911 calls (e.g., an access terminal that does not have credentials or permissions to register with the restricted femto node).

For convenience, the disclosure herein describes various functionality in the context of a femto node. However, it should be clear that a pico node may provide the same or similar functionality as a femto node, except for a larger coverage area. For example, a pico node may be restricted, a home pico node may be defined for a given access terminal, and so on.

A wireless multiple-access communication system may simultaneously support communication for multiple wireless access terminals. As described above, each terminal can communicate with one or more base stations via transmissions on the forward and reverse links. The forward link (or downlink) refers to the communication link from the base stations to the terminals, and the reverse link (or uplink) refers to the communication link from the terminals to the base stations. The communication link may be established by a single-input single-output system, a MIMO system, or some other type of system.

The various illustrative logics, logical blocks, modules, components, and circuits described in connection with the embodiments disclosed herein may be implemented or performed with a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but, in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. Further, at least one processor may comprise one or more modules operable to perform one or more of the steps and/or actions described above. An exemplary storage medium may be coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. In addition, in some aspects, the processor and the storage medium may reside in an ASIC. Further, the ASIC may reside in a user terminal. In the alternative, the processor and the storage medium may reside as discrete components in a user terminal.

In one or more aspects, the functions, methods, or algorithms described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium, which may be incorporated into a computer program product. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Moreover, substantially any connection may be termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, includes Compact Disc (CD), laser disc, optical disc, Digital Versatile Disc (DVD), floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

While the foregoing disclosure discusses illustrative aspects and/or embodiments, it should be noted that various changes and modifications could be made herein without departing from the scope of the described aspects and/or embodiments as defined by the appended claims. Furthermore, although elements of the described aspects and/or embodiments may be described or claimed in the singular, the plural is contemplated unless limitation to the singular is explicitly stated. Moreover, all or a portion of any aspect and/or embodiment may be utilized with all or a portion of any other aspect and/or embodiment, unless stated otherwise.

Claims (62)

1. A method for setting a rise-over-thermal (RoT) threshold for a femtocell access point, comprising:

receiving one or more parameters corresponding to one or more access points;

determining a RoT threshold for the femtocell access point based at least in part on the one or more parameters; and

setting the RoT threshold at the femtocell access point.

2. The method of claim 1, wherein the receiving one or more parameters comprises:

obtaining a first pathloss measurement of at least one device to the femtocell access point, and obtaining a second pathloss measurement of the at least one device to a second access point.

3. The method of claim 2, wherein the receiving one or more parameters comprises:

obtaining an additional first pathloss measurement from at least another device to the femtocell access point, and obtaining an additional second pathloss measurement from the at least another device to the second access point, and wherein the step of determining the RoT threshold is further based at least in part on a function of a difference between the additional first pathloss measurement and the additional second pathloss measurement.

4. The method of claim 2, wherein the receiving one or more parameters further comprises:

obtaining one or more additional pathloss measurements of the at least one device to one or more additional access points, and wherein the determining the RoT is based at least in part on a function of a difference between the first pathloss measurement and a minimum of the second pathloss measurement and the one or more additional pathloss measurements.

5. The method of claim 2, wherein the at least one device is a network listen module co-located within the femtocell access point.

6. The method of claim 2, further comprising:

as part of a training period, the at least one device is configured to report at least the first path loss measurement and the second path loss measurement.

7. The method of claim 1, further comprising:

determining a maximum transmit power of a device communicating with the femtocell access point; and

determining another RoT threshold based at least in part on the maximum transmit power.

8. The method of claim 7, wherein the setting the RoT threshold comprises:

setting the RoT threshold to be the minimum of the RoT threshold and the another RoT threshold.

9. The method of claim 1, wherein the receiving one or more parameters comprises:

the location of the femtocell access point within a macrocell is received, and the step of determining the RoT threshold is based at least in part on distances computed between the femtocell access point and one or more other access points within the macrocell.

10. An apparatus for setting a rise-over-thermal (RoT) threshold for a femtocell access point, comprising:

at least one processor configured to:

receiving one or more parameters corresponding to one or more access points;

determining a RoT threshold for the femtocell access point based at least in part on the one or more parameters; and

setting the RoT threshold at the femtocell access point; and

a memory coupled to the at least one processor.

11. The apparatus of claim 10, wherein the one or more parameters comprise a first pathloss measurement of at least one device to the femtocell access point and a second pathloss measurement of the at least one device to a second access point.

12. The apparatus of claim 11, wherein the one or more parameters comprise an additional first pathloss measurement from at least another device to the femtocell access point and an additional second pathloss measurement from the at least another device to the second access point, and wherein the at least one processor determines the RoT threshold further based at least in part on a function of a difference between the additional first pathloss measurement and the additional second pathloss measurement.

13. The apparatus of claim 11, wherein the at least one processor is further configured to obtain one or more additional pathloss measurements of the at least one device to one or more additional access points, and wherein the one or more parameters comprise the one or more additional pathloss measurements.

14. The apparatus of claim 11, wherein the at least one device is a network listen module co-located at the femtocell access point.

15. An apparatus for setting a rise-over-thermal (RoT) threshold for a femtocell access point, comprising:

means for receiving one or more parameters corresponding to one or more access points;

means for determining a RoT threshold for the femtocell access point based at least in part on the one or more parameters; and

means for setting the RoT threshold at the femtocell access point.

16. The apparatus of claim 15, wherein the one or more parameters comprise a first pathloss measurement of at least one device to the femtocell access point and a second pathloss measurement of the at least one device to a second access point.

17. The apparatus of claim 16, wherein the one or more parameters comprise an additional first pathloss measurement from at least another device to the femtocell access point and an additional second pathloss measurement from the at least another device to the second access point, and wherein the means for determining determines the RoT threshold further based at least in part on a function of a difference between the additional first pathloss measurement and the additional second pathloss measurement.

18. The apparatus of claim 16, wherein the means for receiving further obtains one or more additional pathloss measurements of the at least one device to one or more additional femtocell access points, wherein the one or more parameters further include the one or more additional pathloss measurements.

19. The apparatus of claim 16, further comprising:

means for processing one or more signals from the first access point or the second access point, wherein the at least one device comprises the means for processing.

20. A computer program product for setting a rise-over-thermal (RoT) threshold for a femtocell access point, comprising:

a computer-readable medium, comprising:

code for causing at least one computer to receive one or more parameters corresponding to one or more access points;

code for causing the at least one computer to determine a RoT threshold for the femtocell access point based at least in part on the one or more parameters; and

code for causing the at least one computer to set the RoT threshold at the femtocell access point.

21. The computer program product of claim 20, wherein the one or more parameters comprise a first pathloss measurement of at least one device to the femtocell access point and a second pathloss measurement of the at least one device to a second access point.

22. The computer program product of claim 21, wherein the one or more parameters comprise an additional first pathloss measurement from at least another device to the femtocell access point and an additional second pathloss measurement from the at least another device to the second access point, and wherein the code for causing the at least one computer to determine determines the RoT threshold further based at least in part on a function of a difference between the additional first pathloss measurement and the additional second pathloss measurement.

23. The computer program product of claim 21, wherein the computer-readable medium further comprises:

code for causing the at least one computer to obtain one or more additional pathloss measurements of the at least one device to one or more additional access points, and wherein the one or more parameters comprise the one or more additional pathloss measurements.

24. The computer program product of claim 21, wherein the at least one device is a network listen module co-located at the femtocell access point.

25. An apparatus for setting a rise-over-thermal (RoT) threshold for a femtocell access point, comprising:

a parameter receiving component for receiving one or more parameters corresponding to one or more access points;

a RoT threshold determination component for determining a RoT threshold for the femtocell access point based at least in part on the one or more parameters; and

RoT threshold setting means for setting the RoT threshold at the femtocell access point.

26. The apparatus of claim 25, wherein the one or more parameters comprise a first pathloss measurement of at least one device to the femtocell access point and a second pathloss measurement of the at least one device to a second access point, wherein the one or more parameters comprise the first pathloss measurement and the second pathloss measurement.

27. The apparatus of claim 26, wherein the one or more parameters comprise an additional first pathloss measurement from at least another device to the femtocell access point and an additional second pathloss measurement from the at least another device to the second access point, and wherein the RoT threshold determining component determines the RoT threshold further based at least in part on a function of a difference between the additional first pathloss measurement and the additional second pathloss measurement.

28. The apparatus of claim 26, wherein the parameter receiving component further obtains one or more additional pathloss measurements of the at least one device to one or more additional femtocell access points, wherein the one or more parameters further comprise the one or more additional pathloss measurements.

29. The apparatus of claim 26, further comprising:

a Network Listen Module (NLM) component to process one or more signals from the first access point or the second access point, wherein the at least one device comprises the NLM component.

30. The apparatus of claim 26, further comprising:

a measurement requesting component to configure the at least one device to report at least the first path loss measurement and the second path loss measurement as part of a training period.

31. The apparatus of claim 25, wherein the parameter receiving component determines a maximum transmit power of devices communicating with the femtocell access point, wherein the RoT threshold determining component determines another RoT threshold based at least in part on the maximum transmit power.

32. The apparatus of claim 31, wherein the RoT threshold determining means determines the RoT threshold as a minimum of the RoT threshold and the another RoT threshold.

33. The apparatus of claim 25, wherein the one or more parameters comprise a location of the femtocell access point within a macrocell, and the RoT threshold determining component determines the RoT threshold based at least in part on distances computed between the femtocell access point and one or more other access points within the macrocell.

34. A method for adjusting parameters of an access point based on a determination of interference, comprising:

detecting a strongest transmit power of one or more access points;

determining whether the strongest transmit power exceeds a transmit power used at a femtocell access point; and

adjusting an estimated noise floor of the femtocell access point based at least in part on whether the strongest transmit power exceeds the transmit power.

35. The method of claim 34, further comprising:

estimating a level of out-of-cell interference, wherein the step of adjusting the estimated noise floor is further based at least in part on the level of out-of-cell interference.

36. The method of claim 35, wherein the step of estimating the level of out-of-cell interference comprises measuring noise during a period of time.

37. The method of claim 34, further comprising:

adjusting a rise-over-thermal threshold for the femtocell access point based at least in part on whether the strongest transmit power exceeds the transmit power.

38. The method of claim 34, wherein the step of adjusting the estimated noise floor comprises:

adjusting the estimated noise floor of the femtocell access point for a given device served by a different access point during soft handover.

39. The method of claim 38, further comprising:

requesting an identifier of a device served by the access point during a soft handover; and

receiving an identifier of the given device from the different access point based at least in part on the request.

40. The method of claim 34, further comprising:

enhancing the estimated noise floor during communication with the at least one device.

41. An apparatus for adjusting parameters of an access point based on a determination of interference, comprising:

at least one processor configured to:

detecting a strongest transmit power of one or more access points;

determining whether the strongest transmit power exceeds a transmit power used at a femtocell access point; and

adjusting a noise floor of the femtocell access point based at least in part on whether the strongest transmit power exceeds the transmit power; and

a memory coupled to the at least one processor.

42. The apparatus of claim 41, in which the at least one processor is further configured to estimate a level of out-of-cell interference, in which the at least one processor adjusts the noise floor further based at least in part on the level of out-of-cell interference.

43. The apparatus of claim 41, wherein the at least one processor is further configured to adjust a rise-over-thermal threshold for the femtocell access point based at least in part on whether the strongest transmit power exceeds the transmit power.

44. The apparatus of claim 41, wherein the at least one processor adjusts the noise floor of the femtocell access point for a given device served by a different access point during soft handover.

45. The apparatus of claim 44, wherein the at least one processor is further configured to request identifiers of devices served by the access point during soft handover, and to receive the identifier of the given device from the different access point based at least in part on the request.

46. An apparatus for adjusting parameters of an access point based on a determination of interference, comprising:

means for detecting a strongest transmit power of one or more access points; and

means for adjusting a noise floor of a femtocell access point based at least in part on determining whether the strongest transmit power exceeds a transmit power of the femtocell access point.

47. The apparatus of claim 46, wherein the means for detecting further estimates a level of out-of-cell interference, and the means for adjusting adjusts the noise floor further based at least in part on the level of out-of-cell interference.

48. The apparatus of claim 46, further comprising:

means for adjusting a rise-over-thermal threshold for the femtocell access point based at least in part on whether the strongest transmit power exceeds the transmit power.

49. The apparatus of claim 46, wherein the means for adjusting adjusts the noise floor of the femtocell access point for a given device served by a different access point during soft handover.

50. The apparatus of claim 49, further comprising:

means for requesting an identifier of a device served by the access point during a soft handover and receiving an identifier of the given device from the different access point based at least in part on the request.

51. A computer program product for adjusting parameters of an access point based on a determination of interference, comprising:

a computer-readable medium, comprising:

code for causing at least one computer to detect a strongest transmit power of one or more access points;

code for causing the at least one computer to determine whether the strongest transmit power exceeds a transmit power used at a femtocell access point; and

code for causing the at least one computer to adjust a noise floor of the femtocell access point based at least in part on whether the strongest transmit power exceeds the transmit power.

52. The computer program product of claim 51, wherein the computer-readable medium further comprises:

code for causing the at least one computer to estimate a level of out-of-cell interference, wherein the code for causing the at least one computer to adjust adjusts the noise floor further based at least in part on the level of out-of-cell interference.

53. The computer program product of claim 51, wherein the computer-readable medium further comprises:

code for causing the at least one computer to adjust a rise-over-thermal threshold for the femtocell access point based at least in part on whether the strongest transmit power exceeds the transmit power.

54. The computer program product of claim 51, wherein the code for causing the at least one computer to adjust adjusts the noise floor of the femtocell access point for a given device served by a different access point during soft handover.

55. The computer program product of claim 54, wherein the computer-readable medium further comprises:

code for causing the at least one computer to request identifiers of devices served by the access point during a soft handover and receive an identifier of the given device from the different access point based at least in part on the request.

56. An apparatus for adjusting parameters of an access point based on a determination of interference, comprising:

interference determining means for detecting the strongest transmit power of one or more access points; and

a noise floor adjustment component to adjust a noise floor of a femtocell access point based at least in part on determining whether the strongest transmit power exceeds a transmit power of the femtocell access point.

57. The apparatus of claim 56, wherein the interference determining component further estimates a level of out-of-cell interference, and the noise floor adjusting component adjusts the noise floor further based at least in part on the level of out-of-cell interference.

58. The apparatus of claim 57, wherein the interference determining component estimates the level of out-of-cell interference at least in part by measuring noise during a period of time.

59. The apparatus of claim 56, further comprising:

a rise-over-thermal (RoT) threshold adjustment component for adjusting a RoT threshold for the femtocell access point based at least in part on whether the strongest transmit power exceeds the transmit power.

60. The apparatus of claim 56, wherein the noise floor adjustment component adjusts the noise floor of the femtocell access point for a given device served by a different access point during soft handover.

61. The apparatus of claim 60, a Soft Handover (SHO) device request component for requesting an identifier of a device served by the access point during SHO, and receiving the identifier of the given device from the disparate access point based at least in part on the request.

62. The apparatus of claim 56, wherein the noise floor adjustment component reports the noise floor to at least one device.