HK1222281B - Network management - Google Patents

Description

Network Management

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent Application No. 61/863,902, filed on August 8, 2013, entitled “ADVANCED WIRELESS COMMUNICATION SYSTEMS AND TECHNIQUES,” the entire contents of which are incorporated herein by reference.

Technical Field

Embodiments of the present invention relate to network management, and more particularly to wireless network management.

Background Art

With advancements in wireless communication technology, there is a desire to improve the capacity of LTE-A networks by deploying heterogeneous networks, including various cell sizes such as macrocells, microcells, picocells, and femtocells. From a power management perspective, this hierarchical cell structure presents a challenging radio environment with the attendant risk of suboptimally serving a user equipment (UE) by a corresponding evolved Node B (eNB) when a better eNB could serve the UE.

Summary of the Invention

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments described are herein illustrated by way of example and not limitation in the accompanying drawings:

Figure 1 shows an Evolved Packet System;

Figure 2 depicts a network management system;

FIG3 shows a first view of a cellular system;

FIG4 shows a first enlarged view of a portion of a cellular system;

FIG5 shows a second enlarged view of a portion of a cellular system;

FIG6 depicts a third enlarged view of a portion of a cellular system;

FIG7 shows a first flow chart of network management; and

FIG8 shows a second flow chart of network management.

DETAILED DESCRIPTION

1 shows an evolved packet system (EPS) 100. EPS 100 includes an evolved packet core (EPC) 102, eNode Bs (eNBs) 104, user equipment (UEs) 106, and an operator packet data network 108.

The EPC 102 has a mobility management entity (MME) 102-2. The EPC 102 also includes a serving gateway (S-GW) 102-4 and a packet data network gateway (P-GW) 102-6. The S-GW 102-4 is operable to exchange packets with the eNB 104 serving the UE 106. The S-GW 102-4 effectively operates as a router that supports data exchange between the UE 106 and the P-GW 102-6. The P-GW 102-6 acts as a gateway to external packet data networks, such as, for example, the network 108. The P-GW 102-6 also performs other functions such as address allocation, policy enforcement, packet filtering, and routing. It will be appreciated that the packet data network gateway 102-6 communicates with the external packet data network via the SGi interface.

The MME 102-2 performs signaling so that data packets do not pass through the MME 102-2, which decouples data from signaling to support the development of capacity to be used for signaling and data separately. The MME 102-2 is operable to control many aspects of UE 106 participation, such as, for example, paging UE 106, tracking area management, authentication, gateway selection, roaming, security, etc.

The eNB 104 is responsible for providing the air interface LTE-Uu over which the UE 106 can transmit and receive packets. The eNB 104 performs various functions such as, for example, admission control to allow the UE 106 to access the EPS 100, and radio resource management.

The eNB 104 and the MME 102-2 communicate via an S1-MME interface. Optionally and not shown, the eNB 104 may be connected to one or more other eNBs, either directly via an X2 interface or indirectly via an S1-MME interface.

eNB 104 is an embodiment of a group of base stations. The group of base stations may include one or more base stations. Since eNB 104 is shown as serving UE 106, it is referred to as an active base station. Therefore, eNB 104 is an embodiment of a group of active base stations. The group of active base stations may include one or more active base stations. In contrast, if eNB 104 does not serve UE 106 or any other UE, it will be referred to as an inactive base station, making eNB 104 an embodiment of a group of inactive base stations. The group of inactive base stations may include one or more inactive base stations. Typically, a network such as a mobile network has a group of base stations, which includes a group of active base stations and a group of inactive base stations. It is understood by those skilled in the art that an eNB may be a type of "base station" and that embodiments of the present invention may be implemented or realized using one or more base stations.

EPC 102 includes a Home Subscriber Server (HSS) 102-8. HSS 102-8 is a centrally accessible database that contains subscriber data associated with one or more UEs, such as, for example, UE 106.

It is understood by those skilled in the art that the various interfaces described above are implemented to exchange data between UE 106 and P-GW 102-6 using user plane protocols, such as, for example, GPRS Tunneling Protocol User Part (GTP-U) and, for example, Generic Routing Encapsulation (GRE); the latter may be used to implement the S5/S8 interface.

EPS 100 uses multiple signaling protocols. Air interface signaling, via which eNB 104 influences or otherwise controls radio resources used by UE 106, is implemented using Radio Resource Control (RRC) protocol. The S1-MME link or interface is implemented using S1 Application Protocol (S1-AP).

MME 102-2 controls UE 106 using two air interface non-access stratum protocols: the EPS Session Management (ESM) protocol, which controls data flows associated with the external packet data network 108, and the EPS Mobility Management (EMM) protocol, which manages the internal operations of EPC 102. Using the S1-MME and LTE-Uu interfaces, EMM and EMS messages are exchanged with UE 106 using RRC and S1-AP messages.

The GPRS Tunneling Protocol Control (GTP-C) is used to implement S11 interface signaling and S5/S8 interface signaling.

The EPC 102 also includes a Policy Control Rules Function (PCRF) network entity 102-10. The PCRF 102-10 is responsible for establishing a number of performance targets. Examples of performance targets may include at least one of Quality of Service (QoS) and a charging target for each session, the charging target being based on the corresponding or mandated service level and service type for each UE.

Referring to FIG. 2 , an expanded diagram 200 of the network operator's IP network 108 is shown. It will be appreciated that the IP network 108 includes a network management system (NMS) 202. The network management system 202 is used to manage the cell formed by the eNB 104 and other eNBs. The network management system 202 has access to a storage device 204. The storage device 204 is used to store one or more network management policies 206. The network management policies can be used to influence the operation and control of the network provided by one or more eNBs, which form a geographical area known as a cell and provide radio service coverage within or across the geographical area. The network management system 202 is arranged to implement the network management policies 206 by communicating with the P-GW 102-6 via a P-GW communication system 208. Embodiments may be implemented in which the P-GW communication system 208 implements the above-described data and signaling via an SGi interface.

A network management policy may include one or more objectives or criteria against which network performance may be evaluated. One such objective is managing power consumption of at least one of UE 106 and eNB 104 during an exchange, which may include data exchanges, signaling exchanges, or both. The power consumption management objective may aim to reduce at least overall power consumption.

Additionally or alternatively, at least one criterion for which network performance may be evaluated is a performance metric comprising measurements associated with at least one of: received power associated with a user device and at least one active base station, quality of service associated with one or both of the user device and the at least one active base station, traffic load associated with the at least one active base station, a signal-to-noise ratio of a predetermined signal of the user device and at least one of the at least one active base station, a signal-to-noise ratio of a predetermined signal of the user device and at least one of the at least one active base station, interference associated with a predetermined signal of the user device and at least one of the at least one active base station, a location associated with the at least one active base station, a mutual location associated with the user device and the at least one active base station, a plurality of user devices associated with the at least one active base station, and channel state information associated with the at least one active base station, jointly and individually implemented with any and all changes.

Those skilled in the art will appreciate that the network management system 202 may include processing circuitry 210 to perform the processes described herein. The processing circuitry 210 may include at least one of logic, one or more processors, circuitry, and executable code for execution by one or more processors, all with any and all modifications thereto to implement the functions performed by the network management system 202 as described herein.

Referring to FIG. 3 , a diagram of a cellular system 300 provided by multiple eNBs for corresponding cells is shown. The eNB may be an eNB such as eNB 104 described above. In the illustrated embodiment, cellular system 300 includes multiple base station categories, which in turn define corresponding cell categories or cell types. It will be appreciated that the eNB, such as eNB 104 described above, is an embodiment of a base station. The base station category may be defined relative to a predetermined parameter. In the provided embodiment, the predetermined parameter is associated with the base station transmission power. In the provided embodiment, the predetermined parameter is the rated output power (PRAT) of the base station, which is the average power level per base station carrier at the antenna connector during a transmitter on period. The base station may operate in a single carrier, multi-carrier, or carrier aggregation configuration. Also shown in FIG. 3 is UE 106.

It will be appreciated that different PRATs may be defined for different base stations. In the embodiment provided, the rated output power PRATs of the eNBs forming the cellular system 300 correspond to wide area base stations having no PRAT cap, medium range base stations having a PRAT cap of less than or equal to a first corresponding level, such as, for example, +38 dBm, local area base stations having a PRAT cap of less than or equal to a second corresponding level, such as, for example, +24 dBm, and home base stations having a PRAT cap of less than or equal to at least a third corresponding level, such as, for example, +20 dBm, such as, for example, +20 dBm for a first corresponding number, such as, for example, one of the transmit antenna ports, less than or equal to +17 dBm for a second corresponding number, such as, for example, two of the transmit antenna ports, +14 dBm for a third corresponding number, such as, for example, four of the transmit antenna ports, and +11 dBm for a fourth corresponding number, such as, for example, eight of the transmit antenna ports.

In FIG3 , a plurality of larger cells 302 to 314 are provided. In the illustrated embodiment, eight such larger cells 302 to 314 are provided. The larger cells 302 to 314 correspond to eNBs, which are classified as wide-area base stations. A plurality of smaller cells 316 to 326 are provided. In the illustrated embodiment, six such smaller cells 316 to 326 are provided. The smaller cells 316 to 326 correspond to eNBs, which are classified as medium-range base stations.

A number of smaller cells are also provided. In the illustrated embodiment, twenty-one such smaller cells are provided. The smaller cells correspond to eNBs, which are classified as at least one of a local area base station and a home base station. FIG4 shows a smaller base station in more detail.

FIG4 shows a diagram 400 of smaller base stations 402 to 442. In the illustrated embodiment, the smaller base stations may be aggregated into a cell pattern, where cells 402 to 414 form a first cell pattern including a corresponding number of cells, cells 416 to 428 form a second cell pattern including a corresponding number of cells, and cells 430 to 442 form a third cell pattern including a corresponding number of cells. In the illustrated embodiment, the first to third cell patterns are formed from a seven-cell repeating pattern. In the illustrated embodiment, the smaller cells have eNBs corresponding to the home base station category of base stations. While the embodiment uses a normal repeating cell pattern, the embodiment is not limited thereto. An embodiment may be implemented in which the smaller cells do not form a cell pattern. Alternatively or additionally, an embodiment may be implemented in which the first to third cell patterns are different, rather than a repeating cell pattern, and in particular, rather than a seven-cell repeating cell pattern.

The eNB of a cell may have one of many predefined states. Embodiments may be implemented in which the eNB of a cell has one of two states. Embodiments may be implemented in which the eNB of a cell is in an on state or an off state. The on state is defined as a state in which the eNB of a cell is available for serving user equipment. The eNB may be available for serving a UE by transmitting, for example, a control signal, which allows the user equipment to select the eNB of the cell as a preferred eNB to provide service to the UE. The on state is an embodiment of an active state. The eNB in the on state is an embodiment of an active base station. The off state is defined as a state in which the eNB of a cell is not in the on state. Therefore, an embodiment of the off state is a state in which the eNB of a cell is not available for serving user equipment. The off state is an embodiment of an inactive state. The eNB in the off state is an embodiment of an inactive base station.

In the illustrated embodiment, cells 418, 424, 426, 428, 438, and 440 have one or more corresponding eNBs in an active state. In the illustrated embodiment, all of the remaining cells have one or more eNBs in an inactive state.

Cell 426 is shown as having an active eNB serving UE 106 by dashed line 444 connecting UE 106 and cell 426. A cell is said to be serving a UE when its eNB is supporting data transfer or other exchanges with UE 106 or supports at least that kind of transfer or other exchanges.

It will be appreciated that the geographic distribution of cells 418, 424, 426, 428, 438, and 440 that are turned on is suboptimal relative to current network requirements. UE 106 and eNB 104 serving cell 426 will both transmit at a determined power level appropriate for the distance between them and the channel conditions between them. It will also be appreciated that the overall set of smaller cells includes at least two groups of cells: a set of active cells and a set of inactive cells. The set of active cells includes cells 418, 424, 426, 428, 438, and 440. The set of inactive cells includes cells 402, 404, 406, 408, 410, 412, 414, 416, 420, 422, 430, 432, 434, 436, and 442.

Referring to FIG5 , a further view 500 of the smaller cells described above relative to FIG4 is shown. The network management system 202 is arranged to select a first group of inactive cells, i.e., inactive base stations that are to be switched, at least temporarily, to an active state. In the illustrated embodiment, it will be appreciated that inactive cells 406, 408, 410, 412, and 416 have been selected by the network management system 202 to become active. Those skilled in the art will appreciate that selecting this first group of inactive cells is an embodiment of activating a first group of selected base stations in a group of inactive base stations. It will be appreciated that not all inactive base stations may have been selected to become active. While embodiments may embody all inactive base stations selected to become active, such embodiments may have disadvantageous consequences from a power consumption perspective.

Activating inactive cells 406, 408, 410, 412, and 416 changes the radio environment from the perspective of at least UE 106. Network management system 202 is configured to request UE 106 to generate data associated with network performance, such as, for example, data associated with the general radio environment, from the perspective of UE 106. The data associated with network performance, such as, for example, data associated with the radio environment, is used to determine whether a different geographic distribution of cells better serves the needs of UE 106 measured with respect to at least one criterion. In an illustrative embodiment, the at least one criterion is the transmit power of one or more active eNBs, the transmit power of UE 106, or both. Additionally or alternatively, the at least one criterion may be a distance measurement between UE 106 and one or more eNBs of the active cells.

The network management system 202 receives and processes data associated with network performance to determine whether a different geographic distribution of cells would be more appropriate. It will be understood that such receiving and processing is an embodiment of evaluating at least one performance metric associated with at least one active base station of the plurality of active base stations.

In the illustrated embodiment, it will be appreciated that, when measured against the criteria of transmit power or distance, or both, specified above, UE 106 will be better served by the eNB associated with cell 408. Therefore, network management system 202 is arranged to form a further set of active cells. This further set of active cells includes cell 408, which is better suited to serving UE 106. Embodiments may be implemented in which this further set of active cells includes only cell 408, which serves UE 106. The remaining cells, i.e., those previously inactive cells that become active and cells that were otherwise active, may become inactive, assuming that the remaining cells are not required to support UE 106 or any other UEs. It will be appreciated that deactivating such cells is an embodiment of deactivating a selected set of base stations from a plurality of active base stations in response to evaluating at least one performance metric associated with at least one active base station. In this embodiment, only cells 408 that are best suited to serving UE 106 will remain active. It can be appreciated that this improves power consumption for the network as a whole because only the eNB of the active cell 408 and the UE 106 can transmit. It can be appreciated that this also improves power consumption for at least one of the selected cell 408 and the UE 106 because the distance between the selected cell 408 and the UE 106 is less than the distance between the UE 106 and the previous serving cell 426.

Alternatively or additionally, in an achievable embodiment, network management system 202 applies one or more of a set of rules that can be used to expand the further set of active cells. The set of rules can form part of policy 206 described above. Thus, referring to FIG6 , a diagram 600 of an embodiment is shown in which network management system 202 has applied rules that add a further set of cells to the further set of active cells. For example, the further set of cells can include all cells adjacent to selected active cell 408, or selected cells adjacent to selected active cell 408. Network management system 202 is arranged to form a further set of such active cells. Thus, the further set of active cells collectively includes cells 402, 404, 406, 408, 410, 412, and 414. It will be appreciated that mobile UE 106 will have a relatively high chance of moving from the current serving active cell 408 to a cell in the further set of cells (i.e., one of the neighboring cells in the illustrated embodiment).

Alternatively or additionally, network management system 202 may store additional data associated with the network, and this additional data may be used to expand or establish a further set of active cells. For example, data associated with a cell may indicate whether the cell serves, for example, a portion of a highway, road, or other type of road. Thus, the additional data may include cell data identifying other cells associated with the same portion of a highway, road, or other type of road. Thus, network management system 202 is arranged to expand the further set of active cells to include one or more further cells associated with portions of a highway, road, or other type of road. In such an embodiment, the further set of active cells may span an extended geographic area or any other shaped geographic area. It will be appreciated that the further set of active cells may thus include the selected cell and one or more additional cells specified for selection by the data associated with the selected cell. For example, additional data associated with selected cell 408 may indicate that whenever cell 408 is selected, cell 406 must also be selected.

6 , it can be understood that previously active cells 416 , 418 , 424 , 426 , 428 , 438 , and 440 have been made inactive, ie, switched off.

The one or more rules applied by the network management system 202 when constructing the further set of active cells may form part of one or more network management policies of the network management policy 206 .

In an achievable embodiment, an eNB that has been selected to at least temporarily become the active cell is arranged to transmit a predetermined signal that can be used to evaluate network performance, such as, for example, evaluating the general or resulting radio environment. In an achievable embodiment, such a predetermined signal is a reference signal. The reference signal may include a cell-specific reference signal, a UE-specific reference signal, an MBMS reference signal, a location reference signal, a CSI reference signal, a sounding reference signal, or any other signal that can be used by a UE 106 to evaluate the radio environment and provide data associated with the evaluation to the eNB of the cell, where the UE 106 can receive such a signal from the eNB of the cell.

Referring to FIG7 , a flowchart 700 associated with an embodiment is shown. Network management system 202, or more specifically, processing circuitry 210 of NMS 202, may be configured to implement the process depicted in and described with reference to FIG7 . At step 702, a first group of inactive cells is selected from inactive cells of the cellular system. The selected cells of the first group of inactive cells are made active. In an illustrative embodiment, making the first group of cells active includes turning on the cells of the first group of inactive cells, assuming that they were previously in an off state. At step 706, network performance is evaluated against at least one criterion, such as, for example, network performance as a result or performance of the general radio environment. It will be understood that the evaluation at 706 is an embodiment of evaluating at least one performance metric associated with at least one active base station of a plurality of active base stations. In the provided embodiment, the at least one criterion is power consumption of at least one of UE 106 and at least one active base station. Based on the evaluation, a determination is made at step 708 as to which active cell or cells should be disconnected. At step 710, the active cells selected for disconnection are disconnected. It will be appreciated that switching off selected active cells is an embodiment of deactivating a selected set of the plurality of active base stations in response to evaluating a performance metric.

Referring to FIG8 , a flowchart 800 of a further embodiment is shown. Network management system 202, or more specifically, processing circuitry 210 of NMS 202, may be configured to implement the process depicted in and described with reference to FIG8 . At step 802, one or more of the inactive eNBs in the cellular system are selected for a change of state. At step 804, the state change is implemented, wherein the selected one or more eNBs move from an inactive or sleep state to an active state, outputting one or more signals that can be used by a receiving UE to assess channel conditions. At step 806, the selected one or more eNBs are instructed to begin transmitting signals that can be used by a receiving UE to assess channel conditions. At step 808, UE 106 is instructed to provide measurement data associated with channel conditions, i.e., measurement data associated with the radio environment. At step 810, the measurement data is forwarded to a network element, such as, for example, the network management system 202 described above, where, at step 812, a determination is made at the network management system as to whether sufficient measurement data has been collected to make a decision regarding changing or otherwise updating the geographic distribution of active eNBs. If the determination at step 812 is that insufficient such measurement data exists, processing restarts at step 802, where one or more further eNBs are selected to be turned on, and steps 804 through 812 are repeated. For example, network management policy may dictate the application of one or more rules in making such a decision. In an illustrative embodiment, the rule relates to whether measurement data has been received for all base stations indicated for transmitting reference signals. If such measurement data has not been received from all such base stations, steps 804 through 812 may be repeated. Those skilled in the art will appreciate that one or more additional rules may be applied, such as, for example, a determination that measurement data has been received from a specified number or percentage of base stations indicated for transmitting reference signals. If the determination at step 812 is that sufficient measurement data has been collected, the process continues at step 814, where a new distribution of active eNBs is determined. Alternatively or additionally, a determination is made as to whether any currently active eNBs can be switched off. At step 816, any eNBs that are no longer needed or have become redundant are selected for switching off. At step 818, a command is output to implement the decision to switch off any such redundant cells.

Measurement data or other data provided by the UE 106 may include channel quality information (CQI) that is used to allow assessment of the performance of the network, such as, for example, the radio environment.

In an illustrative embodiment, the network management system 202 may implement the method described herein and particularly shown in the above flowchart. Alternatively or additionally, some other network elements or devices may be used to implement the embodiments of the present invention instead of the network management system 202.

The embodiments herein have been described with reference to the selection of passive cells being deterministic. However, the embodiments are not limited thereto. Embodiments may be implemented in which the selection is random.

While the above embodiments have been described with reference to two states, namely, an on state and an off state, the embodiments are not limited thereto. Alternatively or additionally, embodiments are provided in which a predetermined number of states exist. For example, embodiments may be implemented in which three states exist. The three states may be: an active state, in which the cell's eNB is not in a sleep state and is currently serving at least one corresponding user equipment; an intermediate state, in which the cell's eNB is not in a sleep state but is not currently serving at least one corresponding user equipment; and an inactive state, such as a sleep state, in which the cell's eNB is in a low power consumption mode. Embodiments may be implemented in which the low power consumption mode is the off state.

While the eNBs corresponding to cells in cellular system 300 have been categorized as ranging from wide area base stations to local area base stations and home base stations, embodiments are not limited thereto. Any and all embodiments described herein may employ any starting and ending base stations in the base station hierarchy. For example, the largest base station category of cellular system 300 may correspond to local area base stations of various sizes, such as at least one size of home base stations below the local area base station category. Alternatively, the largest area base station category may be a wide area base station, with at least one of the other smaller base stations being of an intermediate base station category, a local area base station category, or a home base station category. The base station categories of the base stations comprising cellular system 300 may include any variation or combination of a predetermined number of base station categories, such as, for example, the wide area base station category, the medium range base station category, the local area base station category, and the home base station category described above, in any and all combinations thereof.

It will be understood that embodiments of the present invention may be implemented in the form of hardware, software, or a combination of hardware and software. Any such software may be stored in the form of a volatile or non-volatile storage device, such as, for example, a storage device such as a ROM, whether erasable or rewritable, or in the form of a memory, such as, for example, a RAM, a memory chip, a device or an integrated circuit, or a machine-readable storage device, such as, for example, a DVD, a memory stick, or a solid-state medium. It will be understood that storage devices and storage media are embodiments of non-transitory machine-readable storage devices suitable for storing a program or multiple programs comprising instructions that, when executed, implement the embodiments described and claimed herein. Thus, embodiments provide machine executable code for implementing systems, devices, apparatus, or methods as described or claimed herein, and non-transitory machine-readable storage devices for storing such programs. Further, such programs may be delivered electronically via any medium such as a communication signal, which is transmitted via a wired or wireless connection, and embodiments appropriately include such content.

Any such hardware may take the form of a suitably programmable processor, such as, for example, a programmable general-purpose processor designed for mobile devices, an FPGA, or an ASIC. The foregoing may constitute embodiments of processing circuitry to perform the functions of the above examples and embodiments. Any such hardware may also take the form of a chip or chipset arranged to operate in accordance with any one or more of the above-described diagrams, with such diagrams and associated descriptions being accompanied by any and all variations.

Although examples and embodiments have been described separately from their accompanying drawings, the embodiments are not limited thereto. Embodiments may be implemented in which any and all variations of the embodiments or examples associated with the drawings are incorporated. For example, features of FIG. 1 and/or the features described therein may be combined with features of FIG. 2 or the features described therein, and so on.

Where variations of examples or embodiments have been presented as members of at least an enumerated list, either with or without the accompanying language "with any and all variations," it is clear that all variations of that enumerated list member are contemplated, as further emphasized by the accompanying language "with any and all variations" or, where appropriate, "with any and all combinations."

In the embodiments described herein, it will be understood that a group may include one or more members. Thus, for example, a group of passive eNBs may include a single passive eNB or multiple passive eNBs. Furthermore, the terms "active cell" and "passive cell" may be used concurrently with the terms "active base station," "active eNB," and "passive base station" and "passive eNB."

While the above embodiments have been described with reference to the use of evaluation criteria, alternative or additional embodiments may be implemented in which complex criteria are established. For example, the complex criteria may include formulating and solving a multivariable optimization problem using linear programming techniques such as the simplex method. The multivariable optimization may attempt to achieve a balance between multiple variables such as, for example, UE power consumption and signal-to-noise ratio.

Embodiments of the present invention may be applied, for example, to broadband wireless wide area networks (WWANs). However, the embodiments are not limited thereto and may be applied to other types of wireless networks in which the same or similar advantages may be achieved. Such networks specifically include wireless local area networks (WLANs), wireless personal area networks (WPANs), and/or wireless metropolitan area networks (WMANs), where applicable. Further, embodiments may be implemented using one or more access and modulation techniques, such as, for example, orthogonal frequency division multiplexing (OFDM) or multi-user OFDM, which is otherwise known as orthogonal frequency division multiple access (OFDMA), as well as, for example, other air interfaces, including single carrier communication channels or, where appropriately applicable, combinations of protocols or other air interfaces.

Furthermore, embodiments may be used in a variety of applications, including transmitters and receivers of radio systems, although the invention is not limited in this respect. Radio systems specifically included within the scope of embodiments of the present invention include, but are not limited to, network interface cards (NICs), network adapters, fixed or mobile client devices, relays, base stations, femtocells, gateways, bridges, hubs, routers, access points, or other network devices. Further, radio systems within the scope of embodiments of the present invention may be implemented in cellular wireless telephone systems, satellite systems, two-way radio systems, and computing devices including such radio systems with personal computers (PCs), tablet computers and related peripherals, personal digital assistants (PDAs), personal computing accessories, handheld communication devices, and all systems to which the principles of the inventive embodiments are essentially related and to which the principles of the inventive embodiments may be appropriately applied.

Furthermore, the above embodiments have been described with reference to a 3GPP LTE network. However, the embodiments are not limited to this type of network. The embodiments may be implemented in the context of another type of network, such as, for example, an IEEE 802.11 or IEEE 801.16 wireless network or any other type of network.

Although the embodiments of the present invention have been described as being implemented by a network management system, the embodiments are not limited thereto. The embodiments may be implemented or realized by another device capable of influencing the operation of a base station of a cell of a cellular system (such as the eNB described above), or by any one or more of the network elements described with reference to FIG. 1 (such as, for example, MME 102-2, S-GW 102-4, P-GW 102-6, PCRF 102-10), or by any other device such as, for example, another network device forming part of external data packet network 108.

Although the above embodiments have been described with reference to UE 106 and eNB 104, the embodiments are not limited thereto. Embodiments may be implemented where a mobile network includes multiple UEs and multiple base stations.

The above embodiments have been described with reference to evaluating at least one performance metric associated with at least one of the plurality of active base stations. However, embodiments may be implemented in which the evaluation is based on one or more performance metrics, such as, for example, power consumption or interference of UE 106 and eNB 104. Furthermore, while embodiments have been described with reference to at least one performance metric in which the evaluation is based on at least one performance metric associated with at least one of the plurality of active base stations, embodiments may additionally or alternatively be implemented in which a plurality of performance metrics, each associated with at least one of a respective UE and a respective base station, are used as a basis for determining which active cells should be rendered inactive.

Embodiments may be implemented according to any of the following clauses, jointly and individually, in any and all variations:

Clause 1: A method for managing a group of base stations of a wireless cell serving a user equipment, the group of base stations comprising a group of active base stations and a group of inactive base stations, the method comprising: activating a first selected group of base stations of the group of inactive base stations, evaluating at least one performance metric associated with at least one of the active base stations; and deactivating a selected group of active base stations in response to the evaluation.

Clause 2: The method of clause 1, wherein the evaluating comprises evaluating at least one performance metric associated with a radio environment of at least one active base station.

Clause 3: A method according to any one of clauses 1 and 2, wherein the performance metric comprises a measurement associated with at least one of: received power associated with the user equipment and at least one active base station, quality of service associated with the user equipment and one or both of the at least one active base station, traffic load associated with the at least one active base station, a signal-to-noise ratio of a predetermined signal of the user equipment and at least one of the at least one active base station, a signal-to-noise ratio of a predetermined signal of the user equipment and at least one of the at least one active base station, interference associated with the predetermined signal of the user equipment and at least one of the at least one active base station, a position associated with the at least one active base station, a mutual position associated with the user equipment and the at least one active base station, a plurality of user equipment associated with the at least one active base station, and channel state information associated with the user equipment and the at least one active base station.

Clause 4: A method as described in any of clauses 1 to 3, wherein evaluating comprises requesting the user equipment to provide measurement data associated with at least one active base station.

Clause 5: The method of clause 4, wherein the measurement report includes data related to a reference signal associated with at least one active base station.

Clause 6: The method of clause 5, wherein the reference signal comprises at least one of a channel state information reference signal, a cell-specific reference signal, a location reference signal, a sounding reference signal, and a demodulation reference signal.

Clause 7: A method as described in any preceding clause, wherein the evaluating comprises determining one or more distances associated with the user equipment and at least one active base station.

Clause 8: A method as recited in any preceding clause, wherein activating the first set of selected base stations comprises evaluating criteria associated with active base stations.

Clause 9: The method of clause 8, wherein the criteria associated with the active base station comprises evaluating criteria associated with at least one other active base station.

Clause 10: The method of clause 9, wherein the criteria associated with the active base station comprises criteria associated with one or more active base stations of different categories.

Clause 11: A method as described in any preceding clause, wherein the evaluating comprises establishing a multivariable optimization criterion associated with the user equipment and the active base station and solving the multivariable optimization criterion.

Clause 12: A method as set forth in any preceding clause, wherein the base stations comprise at least one or more of: at least two wireless eNBs serving a common geographical area, and at least two wireless base stations of different categories in a hierarchical arrangement of base stations.

Clause 13: A method of network management, the network comprising a plurality of wireless cells, the plurality of wireless cells comprising one or more active wireless cells and one or more inactive wireless cells, the method comprising adjusting a geographical distribution of at least one of the active and inactive wireless cells, evaluating measurements associated with a radio environment of the adjusted geographical distribution of the wireless cells, and in response to the evaluation, implementing at least one of activating an inactive cell and rendering an active cell inactive.

Clause 14: An apparatus for managing a plurality of base stations of a wireless cell for serving a user equipment, the plurality of wireless base stations comprising a group of active base stations and a group of inactive base stations, the apparatus comprising a processing circuit for: activating a first group of inactive base stations of the group of inactive base stations, evaluating a radio environment associated with the active base stations; and deactivating a group of active base stations in response to the evaluation.

Clause 15: The apparatus of clause 14, wherein the processing circuitry for evaluating a radio environment associated with an active base station comprises processing circuitry for evaluating at least one criterion associated with a radio environment.

Clause 16: An apparatus according to clause 15, wherein the criteria associated with the radio environment include measurements associated with at least one of the following items: received power associated with the user equipment and at least one active base station, quality of service associated with one or both of the user equipment and the at least one active base station, traffic load associated with the at least one active base station, a signal-to-noise ratio of a predetermined signal of the user equipment and at least one of the at least one active base station, a signal-to-noise ratio of a predetermined signal of the user equipment and at least one of the at least one active base station, interference associated with the predetermined signal of the user equipment and at least one of the at least one active base station, a position associated with the at least one active base station, a mutual position associated with the user equipment and the at least one active base station, a plurality of user equipment associated with the at least one active base station, and channel state information associated with the user equipment and the at least one active base station.

Clause 17: An apparatus as described in any of clauses 14 to 16, wherein the processing circuitry for assessing the radio environment associated with the active base station comprises processing circuitry for requesting the user equipment to provide measurement data associated with the active base station.

Clause 18: The apparatus of clause 17, wherein the measurement report comprises data related to a reference signal associated with at least one of the user equipment and the at least one active base station.

Clause 19: The apparatus of clause 18, wherein the reference signal comprises at least one of a channel state information reference signal, a cell-specific reference signal, a location reference signal, a sounding reference signal, and a demodulation reference signal.

Clause 20: Apparatus according to any of clauses 14 to 19, wherein the processing circuitry for assessing a radio environment associated with an active base station comprises processing circuitry for determining one or more distances associated with a user equipment and the active base station.

Clause 21: Apparatus according to any of clauses 14 to 20, wherein the processing circuitry for activating the first set of inactive base stations comprises processing circuitry for evaluating criteria associated with the active base stations.

Clause 22: The apparatus of clause 21, wherein the criteria associated with the active base station comprises evaluating criteria associated with at least one other active base station.

Clause 23: The apparatus of clause 22, wherein the criteria associated with the active base station comprises criteria associated with one or more base stations of different categories.

Clause 24: Apparatus according to any of clauses 14 to 23, wherein the processing circuitry for assessing the radio environment comprises processing circuitry for establishing and solving a multivariable optimization criterion associated with the user equipment and the base station.

Clause 25: Apparatus according to any of clauses 14 to 24, wherein the base station comprises one or more of: at least two wireless base stations serving a common geographical area, and at least two wireless base stations of different categories in a hierarchical arrangement of the plurality of base stations.

Clause 26: An apparatus for network management, the network comprising a plurality of wireless cells, the plurality of wireless cells comprising one or more active wireless cells and one or more inactive wireless cells, the apparatus comprising a processing circuit configured to: adjust a geographical distribution of at least one of the active and inactive wireless cells, evaluate network performance associated with a radio environment of the adjusted geographical distribution of the wireless cells, and activate an inactive cell in response to the processing circuit evaluating the network performance, or render an active cell inactive in response to the processing circuit evaluating the network performance.

Clause 27: A computer executable program code comprising instructions arranged, when executed, to perform the method of any one of clauses 1 to 13.

Clause 28: A computer-readable storage device storing the computer-executable program code of Clause 27.

Clause 29: A method, eNodeB, apparatus, network element, computer program and computer readable storage device substantially as herein described with reference to and/or as illustrated in the accompanying drawings.

Clause 30: An apparatus for managing a group of eNBs serving user equipment, the apparatus comprising processing circuitry configured to:

processing data defining a geographic radio service area provided by the set of eNBs, wherein the set of eNBs comprises: a first set of eNBs in a first respective power state, the first set of eNBs being available to serve the user equipment, and a second set of eNBs in a second respective power state, the second set of eNBs being unavailable to serve the user equipment, the processing circuitry for processing the data defining the geographic radio service area comprising processing circuitry for:

adjusting the data defining a geographic radio service area provided by a group of eNBs by changing at least one eNB of the second group of eNBs from the second respective power state to a first respective power state in the first group of eNBs, thereby defining an adjusted geographic radio service area for provision by the group of eNBs,

processing performance data associated with a modified geographic radio service area provided by a set of eNBs, and

In response to the processing, data defining a further radio service area provided by the first group of eNBs is established.

Clause 31: The apparatus of clause 30, wherein the processing circuitry for said establishing comprises: transitioning at least one eNB of a first set of eNBs from a first respective power state to a second set of eNBs having a second respective power state.

Clause 32: An apparatus according to any one of clauses 30 and 31, wherein the processing of performance data associated with a modified geographic radio service area provided by a group of eNBs comprises: processing performance metrics associated with the user equipment and at least one of at least one eNB of the first group of eNBs to determine whether the performance of the first group of eNBs satisfies the at least one criterion.

Clause 33: The apparatus of clause 32, wherein the establishing comprises adjusting data defining the modified geographic radio service area to provide a different geographic radio service area.

Clause 34: The apparatus of clause 33, wherein said adjusting data defining the modified geographic radio service area to provide a different geographic radio service area comprises at least one of:

Switching a first eNB of the first group of eNBs that was previously in the second group of eNBs back to the second group of eNBs having the second corresponding power state, and switching a first eNB of the first group of eNBs in the first group of eNBs to the second group of eNBs having the second corresponding power state.

Clause 35: An apparatus according to clause 32, wherein the at least one criterion comprises a measurement associated with at least one of: received power associated with the user equipment and at least one eNB of the first group of eNBs, quality of service associated with the user equipment and one or both of the at least one eNB of the first group of eNBs, traffic load associated with the at least one eNB of the first group of eNBs, a signal-to-noise ratio of a predetermined signal of the user equipment and at least one of the at least one eNB of the first group of eNBs, a signal-to-noise ratio of a predetermined signal of the user equipment and at least one of the at least one eNB of the first group of eNBs, interference associated with the predetermined signal of the user equipment and at least one of the at least one eNB of the first group of eNBs, a location associated with the at least one eNB of the first group of eNBs, a mutual location associated with the user equipment and at least one eNB of the first group of eNBs, a number of user equipment associated with the at least one eNB of the first group of eNBs, and channel state information associated with the user equipment and the at least one eNB of the first group of eNBs.

Clause 36: Apparatus according to any of clauses 30 to 35, wherein the processing circuitry comprises processing circuitry for requesting the user equipment to provide measurement data associated with one or more eNBs of the first set of eNBs.

Clause 37: The apparatus of clause 36, wherein the measurement data comprises data associated with a reference signal associated with at least one of the user equipment and at least one eNB of the first set of eNBs.

Clause 38: The apparatus of clause 37, wherein the reference signal comprises at least one of a channel state information reference signal, a cell-specific reference signal, a location reference signal, a sounding reference signal, and a demodulation reference signal.

Clause 39: Apparatus according to any of clauses 30 to 38, wherein the processing circuitry for processing the performance data comprises processing circuitry to determine one or more distances associated with the user equipment and one or more eNBs of the first set of eNBs.

Clause 40: An apparatus according to any one of clauses 30 to 39, wherein the processing circuit for processing performance data associated with the adjusted geographic radio service area provided by the first group of eNBs includes processing circuitry for establishing a multivariable optimization criterion associated with the user equipment and at least one eNB of the first group of eNBs, and processing circuitry for solving the multivariable optimization criterion.

Clause 41: An apparatus according to clause 40, wherein the processing circuit for establishing data for defining a further geographic radio service area provided by the first group of eNBs includes: selecting one or more eNBs of the first group of eNBs to provide data for defining a further geographic radio service area provided by the first group of eNBs based on the solution of the multivariable optimization criterion.

Clause 42: An apparatus according to any of clauses 30 to 41, further comprising processing circuitry to output a request to a user equipment and at least one of one or more eNBs of the first set of eNBs to provide measurement data associated with a radio environment provided by at least part of the modified geographic radio service area.

Clause 43: The apparatus of clause 41, further comprising processing circuitry for receiving performance data in response to outputting a request to the user equipment and at least one of the one or more eNBs of the first set of eNBs to provide measurement data, the measurement data being associated with a radio environment provided by at least a portion of the modified geographic radio service area.

Clause 44: Apparatus according to any of clauses 30 to 43, further comprising processing circuitry for outputting instructions to one or more eNBs of the first set of eNBs and to one or more of the second set of eNBs in a corresponding power state.

Clause 45: An apparatus for network management, the network comprising a plurality of wireless cells, the plurality of wireless cells comprising one or more active wireless cells and one or more inactive wireless cells, the apparatus comprising a processing circuit, the processing circuit being configured to: adjust a geographic distribution of at least one of the active and inactive wireless cells, evaluate network performance associated with the adjusted geographic distribution of the wireless cells, and activate an inactive cell in response to the processing circuit evaluating the network performance or render an active cell inactive in response to the processing circuit evaluating the network performance.

Claims (24)

1. An apparatus for managing a plurality of base stations in a wireless cell for serving user equipment, the plurality of wireless base stations comprising a group of active base stations and a group of inactive base stations, the apparatus comprising: A storage device for storing network management policies, wherein the network management policies include one or more criteria associated with network performance evaluation; and A processing circuit coupled to the storage device and configured to: activate a first group of inactive base stations based on the network management policy; evaluate the radio environment associated with the active base stations after activating the first group of inactive base stations; and deactivate a group of base stations of the active base stations in response to the evaluation. 2. The apparatus of claim 1, wherein the processing circuitry for evaluating the radio environment associated with the active base station comprises: processing circuitry for evaluating at least one criterion associated with the radio environment. 3. The apparatus of claim 2, wherein the criteria associated with the radio environment include measurements associated with at least one of the following: received power associated with the user equipment and at least one active base station; quality of service associated with one or both of the user equipment and at least one active base station; traffic load associated with at least one active base station; signal-to-noise ratio of a predetermined signal of the user equipment and at least one of the at least one active base station; signal-to-noise ratio of a predetermined signal of the user equipment and at least one of the at least one active base station; interference associated with a predetermined signal of the user equipment and at least one of the at least one active base station; location associated with at least one active base station; mutual location associated with the user equipment and at least one active base station; multiple user equipments associated with at least one active base station; and channel state information associated with the user equipment and at least one active base station. 4. The apparatus according to any one of claims 1 to 3, wherein the processing circuitry for evaluating the radio environment associated with the active base station comprises: processing circuitry for requesting the user equipment to provide measurement data associated with the active base station. 5. The apparatus of claim 4, wherein the measurement data includes data associated with a reference signal, the reference signal being associated with at least one of a user equipment and at least one active base station. 6. The apparatus of claim 5, wherein the reference signal includes at least one of a channel state information reference signal, a cell-specific reference signal, a location reference signal, a detection reference signal, and a demodulation reference signal. 7. The apparatus of claim 1, wherein the processing circuitry for evaluating the radio environment associated with the active base station comprises: processing circuitry for determining one or more distances associated with the user equipment and the active base station. 8. The apparatus of claim 1, wherein the processing circuitry for activating the first group of inactive base stations comprises: processing circuitry for evaluating criteria associated with the active base stations. 9. The apparatus of claim 8, wherein the criteria associated with the active base station include: evaluating criteria associated with at least one other active base station. 10. The apparatus of claim 9, wherein the criteria associated with the active base station include criteria associated with one or more base stations of different categories. 11. The apparatus of claim 1, wherein the processing circuitry for evaluating the radio environment comprises: processing circuitry for establishing and solving a multivariate optimization criterion associated with user equipment and base stations. 12. The apparatus of claim 1, wherein the base station comprises one or more of the following: at least two wireless base stations serving a common geographical area, and at least two wireless base stations of different categories in a hierarchical arrangement of multiple base stations. 13. A method for managing a group of base stations in a wireless cell serving a user equipment, the group of base stations comprising a group of active base stations and a group of inactive base stations, the method comprising: activating a first group of selected base stations from the group of inactive base stations based on a network management policy; evaluating at least one performance metric associated with at least one active base station from the group of active base stations after activating the first group of selected base stations, wherein the network management policy includes one or more criteria associated with and being performance metrics for evaluating network performance; and deactivating the selected group of active base stations in response to the evaluation. 14. The method of claim 13, wherein the evaluation comprises: evaluating at least one performance metric associated with the radio environment of at least one active base station. 15. The method of claim 13 or 14, wherein the performance metric includes a measurement associated with at least one of the following: received power associated with the user equipment and at least one active base station; quality of service associated with one or both of the user equipment and at least one active base station; traffic load associated with at least one active base station; signal-to-noise ratio of a predetermined signal of the user equipment and at least one of the at least one active base station; signal-to-noise ratio of a predetermined signal of the user equipment and at least one of the at least one active base station; interference associated with a predetermined signal of the user equipment and at least one of the at least one active base station; location associated with at least one active base station; mutual location associated with the user equipment and at least one active base station; a plurality of user equipments associated with at least one active base station; and channel state information associated with the user equipment and at least one active base station. 16. The method of claim 13, wherein the evaluation comprises: requesting the user equipment to provide measurement data associated with at least one active base station. 17. The method of claim 16, wherein the measurement data includes data associated with a reference signal, the reference signal being associated with at least one active base station. 18. The method of claim 17, wherein the reference signal includes at least one of a channel state information reference signal, a cell-specific reference signal, a location reference signal, a detection reference signal, and a demodulation reference signal. 19. The method of claim 13, wherein the evaluation comprises: determining one or more distances associated with the user equipment and at least one active base station. 20. The method of claim 13, wherein activating the first group of selected base stations comprises: evaluating criteria associated with the active base stations. 21. The method of claim 20, wherein the criteria associated with the active base station include: evaluating criteria associated with at least one other active base station. 22. The method of claim 21, wherein the criteria associated with the active base station include criteria associated with one or more active base stations of different categories. 23. The method of claim 13, wherein the evaluation comprises: establishing a multivariate optimization criterion associated with user equipment and active base stations and solving the multivariate optimization criterion. 24. A non-transient storage medium storing computer-executable program code, the computer-executable program code including instructions, when executed, arranged to carry out the method of any one of claims 13-23.