HK1251761B - User equipment (ue) and methods for dynamic millimeter wave pencil cell communication - Google Patents

Description

User equipment (UE) and method for dynamic millimeter wave pencil cell communications

Priority claim

This application claims priority to U.S. Provisional Patent Application Serial No. 62/198,247, filed on July 29, 2015, which is incorporated herein by reference in its entirety.

Technical Field

Embodiments pertain to wireless communications. Some embodiments relate to wireless networks including 3GPP (3rd Generation Partnership Project) networks, 3GPP LTE (Long Term Evolution) networks, and 3GPP LTE-A (LTE-Advanced) networks, but the scope of the embodiments is not limited thereto. Some embodiments relate to Wireless Gigabit Alliance (WiGIG) networks. Some embodiments relate to fifth generation (5G) networks. Some embodiments relate to communications using pencil cells, small cells, and/or macro cells. Some embodiments relate to millimeter wave (mmW) communications.

Background Art

Mobile networks can support communications with mobile devices. In some cases, small cells can be deployed within macro cells to provide localized communications to mobile devices. For example, when a large number of people gather at a particular location and/or event, the demand for data communications and/or other communications may increase. Although the use of small cells can alleviate the increased demand to some extent, mobile networks may still become overloaded in some cases. Therefore, there is a general need for methods and systems for enabling communications between mobile devices and networks in these and other scenarios.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a functional diagram of a 3GPP network according to some embodiments;

FIG2 is a block diagram of a user equipment (UE) according to some embodiments;

FIG3 is a block diagram of an evolved Node B (eNB) according to some embodiments;

FIG4 is a block diagram of a small cell access point (AP) according to some embodiments;

FIG5 illustrates an example of a scenario in which a UE may communicate with a macro cell eNB and with multiple small cell APs according to some embodiments;

FIG6 illustrates the operation of a communication method according to some embodiments;

FIG7 illustrates another example of a communication method according to some embodiments;

FIG8 illustrates an example of communication between a UE and a macro cell eNB according to some embodiments;

FIG9 illustrates another example of a communication method according to some embodiments;

FIG10 illustrates an example reference signal according to some embodiments; and

FIG11 illustrates an example of transmission of reference signals according to various periodicity parameters in accordance with some embodiments.

DETAILED DESCRIPTION

The following description and accompanying drawings illustrate specific embodiments sufficiently to enable those skilled in the art to practice them. Other embodiments may include structural, logical, electrical, process, and other variations. Portions or features of some embodiments may be included in or substituted for portions and features of other embodiments. The embodiments set forth in the claims encompass all available equivalents of those claims.

1 is a functional diagram of a 3GPP network according to some embodiments. The network includes a radio access network (RAN) (e.g., as depicted, E-UTRAN or Evolved Universal Terrestrial Radio Access Network) 100 and a core network 120 (e.g., shown as an Evolved Packet Core (EPC)), which are coupled together via an S1 interface 115. For convenience and simplicity, only a portion of the core network 120 and the RAN 100 are shown.

The core network 120 includes a mobility management entity (MME) 122, a serving gateway (serving GW) 124, and a packet data network gateway (PDN GW) 126. The RAN 100 includes an evolved Node B (eNB) 104 (which may operate as a base station) for communicating with a user equipment (UE) 102. The eNB 104 may include a macro eNB and a low power (LP) eNB.

The MME 122 is functionally similar to the control plane of a legacy Serving GPRS Support Node (SGSN). The MME 122 manages mobility aspects of access (e.g., gateway selection and tracking area list management). The Serving GW 124 terminates the interface toward the RAN 100 and routes data packets between the RAN 100 and the core network 120. Furthermore, it can be the local mobility anchor for inter-eNB handovers and can also provide an anchor for inter-3GPP mobility. Other responsibilities may include legal interception, charging, and certain policy enforcement. The Serving GW 124 and MME 122 can be implemented in one physical node or in separate physical nodes. The PDN GW 126 terminates the SGi interface toward the packet data network (PDN). The PDN GW 126 routes data packets between the EPC 120 and external PDNs and can be a key node for policy enforcement and charging data collection. It can also provide an anchor for mobility for non-LTE accesses. The external PDN can be any kind of IP network as well as an IP Multimedia Subsystem (IMS) domain. The PDN GW 126 and the Serving GW 124 can be implemented in one physical node or in separate physical nodes.

The eNB 104 (macro and micro eNBs) terminates the air interface protocol and can be the first point of contact for the UE 102. In some embodiments, the eNB 104 can implement various logical functions for the RAN 100, including but not limited to RNC (radio network controller) functions, such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management. According to an embodiment, the UE 102 can be configured to communicate orthogonal frequency division multiplexing (OFDM) communication signals with the eNB 104 over a multi-carrier communication channel in accordance with an orthogonal frequency division multiple access (OFDMA) communication technique. An OFDM signal can include multiple orthogonal subcarriers.

The S1 interface 115 is the interface that separates the RAN 100 from the EPC 120. It is divided into two parts: S1-U, which carries traffic data between the eNB 104 and the Serving GW 124; and S1-MME, which is the signaling interface between the eNB 104 and the MME 122. The X2 interface is an interface between eNBs 104. The X2 interface consists of two parts: X2-C and X2-U. X2-C is the control plane interface between eNBs 104, while X2-U is the user plane interface between eNBs 104.

In some embodiments, the eNB 104, MME 122, and/or other components in the network may be communicatively coupled to one or more small cell access points (APs) 106. The small cell APs 106 may communicate with the UE 102 using techniques such as those described herein, but embodiments are not limited thereto. By way of example, the eNB 104, MME 122, and/or other components may provide the small cell APs 106 with various configuration information related to communications between the UE 102 and the small cell APs 106. For example, communications between the small cell APs 106 and the UE 102 may include exchanging data using pen cell technology, in which signals from the small cell APs 106 may be transmitted in a directional manner and with relatively high gain. The UE 102 may also receive various reference signals from the small cell APs 106. In some cases, the UE 102 and the eNB 104 may exchange various control messages that may be related to measurements used for such reception. These embodiments are described in more detail below.

It should be noted that embodiments are not limited to use of the example 3GPP network shown in FIG1 , as other macrocell networks may be used in some cases. Thus, the small cell AP 106 (or other small cell base station components) may be arranged to perform some or all of the techniques and operations described herein as part of an embodiment that may include any suitable macrocell network.

In the context of cellular networks, LP cells are typically used to extend coverage to indoor areas where outdoor signals don't reach well, or to increase network capacity in areas with high phone usage (e.g., train stations). As used herein, the term low-power (LP) eNB refers to any suitable relatively low-power eNB used to implement narrower cells (e.g., femtocells, picocells, or microcells) (narrower than macrocells). Femtocell eNBs are typically provided by mobile network operators to their residential or enterprise customers. Femtocells are typically the size of a residential gateway or smaller and are typically connected to a user's broadband line. Once plugged in, a femtocell connects to the mobile operator's mobile network and provides additional coverage to the residential femtocell, typically with a range of 30 to 50 meters. Therefore, an LP eNB can be a femtocell eNB because it is coupled through a PDN GW 126. Similarly, a picocell is a wireless communication system that typically covers a small area, such as within a building (office, shopping mall, train station, etc.) or, more recently, within an airplane. A picocell eNB can typically connect to another eNB (e.g., a macro eNB) via an X2 link through its base station controller (BSC) functionality. Thus, an LPeNB can be implemented as a picocell eNB, as it is coupled to the macro eNB via the X2 interface. A picocell eNB or other LPeNB can incorporate some or all of the functionality of a macro eNB. In some cases, this may be referred to as an access point base station or enterprise femtocell.

In some embodiments, a downlink resource grid can be used for downlink transmissions from eNB 104 to UE 102, while uplink transmissions from UE 102 to eNB 104 can utilize similar techniques. The grid can be a time-frequency grid, referred to as a resource grid or time-frequency resource grid, representing the physical resources in the downlink within each time slot. This time-frequency representation is common in OFDM systems, making it intuitive for radio resource allocation. Each column and row of the resource grid corresponds to an OFDM symbol and an OFDM subcarrier, respectively. The duration of the resource grid in the time domain corresponds to a time slot in a radio frame. The smallest time-frequency unit in the resource grid is called a resource element (RE). Each resource grid includes multiple resource blocks (RBs), which describe the mapping of specific physical channels to resource elements. Each resource block comprises a set of resource elements in the frequency domain and may represent the smallest share of resources that can currently be allocated. Several different physical downlink channels are communicated using these resource blocks. Of particular relevance to the present disclosure, two of these physical downlink channels are the physical downlink shared channel and the physical downlink control channel.

The physical downlink shared channel (PDSCH) carries user data and higher-layer signaling to the UE 102 ( FIG. 1 ). The physical downlink control channel (PDCCH) carries information about, among other things, the transport format and resource allocation associated with the PDSCH channel. It also informs the UE 102 of the transport format, resource allocation, and hybrid automatic repeat request (HARQ) information associated with the uplink shared channel. Typically, downlink scheduling (e.g., assigning control channel resource blocks and shared channel resource blocks to UEs 102 within a cell) can be performed at the eNB 104 based on channel quality information fed back from the UE 102 to the eNB 104. Downlink resource assignment information can then be sent to the UE 102 on a control channel (PDCCH) for (and assigned to) the UE 102.

PDCCH uses CCE (control channel elements) to convey control information. Before being mapped to resource elements, PDCCH complex-valued symbols are first organized into quadruplets and then arranged using a sub-block interleaver for rate matching. Each PDCCH is sent using one or more of these control channel elements (CCEs), where each CCE corresponds to nine groups of four physical resource elements called resource element groups (REGs). Four QPSK symbols are mapped to each REG. Depending on the size of the DCI and the channel conditions, PDCCH can be sent using one or more CCEs. There can be four or more different PDCCH formats defined in LTE with different numbers of CCEs (e.g., aggregation levels, L=1, 2, 4, or 8).

As used herein, the term "circuit" may refer to or be part of or include an application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) and/or memory (shared, dedicated, or group) that executes one or more software or firmware programs, combinational logic circuits, and/or other suitable hardware components that provide the described functionality. In some embodiments, the circuit may be implemented in one or more software or firmware modules, or the functionality associated with the circuit may be implemented by one or more software or firmware modules. In some embodiments, the circuit may include logic that is at least partially operable in hardware. The embodiments described herein may be implemented as a system using any suitably configured hardware and/or software.

FIG2 is a block diagram of a user equipment (UE) according to some embodiments. UE 200 may be suitable for use as UE 102, as depicted in FIG1 . In some embodiments, UE 200 may include application circuitry 202, baseband circuitry 204, radio frequency (RF) circuitry 206, front-end module (FEM) circuitry 208, and one or more antennas 210, coupled together at least as shown. In some embodiments, other circuitry or arrangements may include one or more elements and/or components of application circuitry 202, baseband circuitry 204, RF circuitry 206, and/or FEM circuitry 208, and in some cases, may also include other elements and/or components. As an example, "processing circuitry" may include one or more elements and/or components, some or all of which may be included in application circuitry 202 and/or baseband circuitry 204. As another example, "transceiver circuitry" may include one or more elements and/or components, some or all of which may be included in RF circuitry 206 and/or FEM circuitry 208. However, these examples are not limiting, as the processing circuitry and/or the transceiver circuitry may in some cases also include other elements and/or components.

Application circuitry 202 may include one or more application processors. For example, application circuitry 202 may include circuitry such as, but not limited to, one or more single-core processors or multi-core processors. The processors may include any combination of general-purpose processors and specialized processors (e.g., graphics processors, application processors, etc.). The processors may be coupled to and/or include memory/storage and may be configured to execute instructions stored in the memory/storage to enable various applications and/or operating systems to run on the system.

The baseband circuitry 204 may include circuitry such as, but not limited to, one or more single-core processors or multi-core processors. The baseband circuitry 204 may include one or more baseband processors and/or control logic to process baseband signals received from the receive signal path of the RF circuitry 206 and generate baseband signals for the transmit signal path of the RF circuitry 206. The baseband processing circuitry 204 may interface with the application circuitry 202 to generate and process baseband signals and control the operation of the RF circuitry 206. For example, in some embodiments, the baseband circuitry 204 may include a second generation (2G) baseband processor 204a, a third generation (3G) baseband processor 204b, a fourth generation (4G) baseband processor 204c, and/or other baseband processors 204d for other current generations, generations in development, or generations to be developed in the future (e.g., fifth generation (5G), 6G, etc.). Baseband circuitry 204 (e.g., one or more of baseband processors 204a-d) may handle various radio control functions that enable communication with one or more radio networks via RF circuitry 206. Radio control functions may include, but are not limited to, signal modulation/demodulation, encoding/decoding, radio frequency shifting, and the like. In some embodiments, the modulation/demodulation circuitry of baseband circuitry 204 may include fast Fourier transform (FFT), precoding, and/or constellation mapping/demapping functions. In some embodiments, the encoding/decoding circuitry of baseband circuitry 204 may include convolution, tail-biting, turbo, Viterbi, and/or low-density parity check (LDPC) encoder/decoder functions. Embodiments of the modulation/demodulation and encoder/decoder functions are not limited to these examples and may include other suitable functions in other embodiments.

In some embodiments, the baseband circuitry 204 may include elements of a protocol stack, such as elements of the Evolved Universal Terrestrial Radio Access Network (EUTRAN) protocol, including, for example, physical (PHY) elements, medium access control (MAC) elements, radio link control (RLC) elements, packet data convergence protocol (PDCP) elements, and/or radio resource control (RRC) elements. The central processing unit (CPU) 204e of the baseband circuitry 204 may be configured to execute elements of the protocol stack for signaling at the PHY, MAC, RLC, PDCP, and/or RRC layers. In some embodiments, the baseband circuitry may include one or more audio digital signal processors (DSPs) 204f. The audio DSPs 204f may include elements for compression/decompression and echo cancellation, and in other embodiments may include other suitable processing elements. In some embodiments, the components of the baseband circuitry may be suitably combined in a single chip, a single chipset, or deployed on the same circuit board. In some embodiments, some or all components of the baseband circuitry 204 and the application circuitry 202 may be implemented together, for example, on a system-on-chip (SoC).

In some embodiments, baseband circuitry 204 can provide communications compatible with one or more radio technologies. For example, in some embodiments, baseband circuitry 204 can support communications with an Evolved Universal Terrestrial Radio Access Network (EUTRAN) and/or other wireless metropolitan area networks (WMANs), wireless local area networks (WLANs), and wireless personal area networks (WPANs). Embodiments in which baseband circuitry 204 is configured to support radio communications using more than one wireless protocol may be referred to as multimode baseband circuitry.

The RF circuitry 206 may enable communication with a wireless network using modulated electromagnetic radiation over a non-solid medium. In various embodiments, the RF circuitry 206 may include switches, filters, amplifiers, and the like to facilitate communication with the wireless network. The RF circuitry 206 may include a receive signal path that may include circuitry for downconverting RF signals received from the FEM circuitry 208 and providing a baseband signal to the baseband circuitry 204. The RF circuitry 206 may also include a transmit signal path that may include circuitry for upconverting baseband signals provided by the baseband circuitry 204 and providing an RF output signal to the FEM circuitry 208 for transmission.

In some embodiments, RF circuitry 206 may include a receive signal path and a transmit signal path. The receive signal path of RF circuitry 206 may include mixer circuitry 206a, amplifier circuitry 206b, and filter circuitry 206c. The transmit signal path of RF circuitry 206 may include filter circuitry 206c and mixer circuitry 206a. RF circuitry 206 may also include synthesizer circuitry 206d for synthesizing frequencies used by mixer circuitry 206a in the receive and transmit signal paths. In some embodiments, mixer circuitry 206a in the receive signal path may be configured to downconvert the RF signal received from FEM circuitry 208 based on the synthesized frequency provided by synthesizer circuitry 206d. Amplifier circuitry 206b may be configured to amplify the downconverted signal, and filter circuitry 206c may be a low-pass filter (LPF) or a band-pass filter (BPF) configured to remove unwanted signals from the downconverted signal to generate an output baseband signal. The output baseband signal may be provided to baseband circuitry 204 for further processing. In some embodiments, the output baseband signal can be a zero-frequency baseband signal, but this is not a requirement. In some embodiments, the mixer circuit 206a of the receive signal path can include a passive mixer, but the scope of the embodiments is not limited in this regard. In some embodiments, the mixer circuit 206a of the transmit signal path can be configured to upconvert the input baseband signal based on the synthesized frequency provided by the synthesizer circuit 206d to generate an RF output signal for the FEM circuit 208. The baseband signal can be provided by the baseband circuit 204 and can be filtered by the filter circuit 206c. The filter circuit 206c can include a low-pass filter (LPF), but the scope of the embodiments is not limited in this regard.

In some embodiments, the mixer circuit 206a of the receive signal path and the mixer circuit 206a of the transmit signal path may include two or more mixers and may be arranged for quadrature down-conversion and/or up-conversion, respectively. In some embodiments, the mixer circuit 206a of the receive signal path and the mixer circuit 206a of the transmit signal path may include two or more mixers and may be arranged for image rejection (e.g., Hartley image rejection). In some embodiments, the mixer circuit 206a of the receive signal path and the mixer circuit 206a of the transmit signal path may be arranged for direct down-conversion and/or direct up-conversion, respectively. In some embodiments, the mixer circuit 206a of the receive signal path and the mixer circuit 206a of the transmit signal path may be configured for superheterodyne operation.

In some embodiments, the output baseband signal and the input baseband signal may be analog baseband signals, but the scope of the embodiments is not limited in this respect. In some alternative embodiments, the output baseband signal and the input baseband signal may be digital baseband signals. In these alternative embodiments, the RF circuitry 206 may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry, and the baseband circuitry 204 may include a digital baseband interface for communicating with the RF circuitry 206. In some dual-mode embodiments, separate radio IC circuitry may be provided for processing signals for each spectrum, but the scope of the embodiments is not limited in this respect.

In some embodiments, synthesizer circuit 206d may be a fractional-N synthesizer or a fractional-N/N+1 synthesizer, but the scope of the embodiments is not limited in this regard, as other types of frequency synthesizers may be suitable. For example, synthesizer circuit 206d may be a sigma-delta synthesizer, a frequency multiplier, or a synthesizer including a phase-locked loop with a frequency divider. Synthesizer circuit 206d may be configured to synthesize the output frequency used by mixer circuit 206a of RF circuit 206 based on a frequency input and a divider control input. In some embodiments, synthesizer circuit 206d may be a fractional-N/N+1 synthesizer. In some embodiments, the frequency input may be provided by a voltage-controlled oscillator (VCO), but this is not required. Depending on the desired output frequency, the divider control input may be provided by baseband circuit 204 or application processor 202. In some embodiments, the divider control input (e.g., N) may be determined from a lookup table based on the channel indicated by application processor 202.

The synthesizer circuit 206d of the RF circuit 206 may include a divider, a delay-locked loop (DLL), a multiplexer, and a phase accumulator. In some embodiments, the divider may be a dual-modulus divider (DMD), and the phase accumulator may be a digital phase accumulator (DPA). In some embodiments, the DMD may be configured to divide the input signal by N or N+1 (e.g., based on a carry) to provide a fractional division ratio. In some example embodiments, the DLL may include a cascaded set of tunable delay elements, a phase detector, a charge pump, and a D-type flip-flop. In these embodiments, the delay elements may be configured to decompose a VCO cycle into Nd equal phase groups, where Nd is the number of delay elements in the delay line. In this manner, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle.

In some embodiments, synthesizer circuit 206 d can be configured to generate a carrier frequency as an output frequency, while in other embodiments, the output frequency can be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency), and used in conjunction with a quadrature generator and divider circuit to generate multiple signals at the carrier frequency with multiple different phases relative to each other. In some embodiments, the output frequency can be an LO frequency (f _LO ). In some embodiments, RF circuit 206 can include an IQ/polar converter.

FEM circuitry 208 may include a receive signal path, which may include circuitry configured to operate on RF signals received from one or more antennas 210, amplify the received signals, and provide the amplified versions of the received signals to RF circuitry 206 for further processing. FEM circuitry 208 may also include a transmit signal path, which may include circuitry configured to amplify transmit signals provided by RF circuitry 206 for transmission by one or more of the one or more antennas 210.

In some embodiments, the FEM circuitry 208 may include a TX/RX switch to switch between transmit and receive modes of operation. The FEM circuitry may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry may include a low-noise amplifier (LNA) to amplify a received RF signal and provide the amplified received RF signal as an output (e.g., to the RF circuitry 206). The transmit signal path of the FEM circuitry 208 may include a power amplifier (PA) to amplify an input RF signal (e.g., provided by the RF circuitry 206) and one or more filters to generate an RF signal for subsequent transmission, e.g., by one or more of the one or more antennas 210. In some embodiments, the UE 200 may include additional components, such as memory/storage, a display, a camera, sensors, and/or input/output (I/O) interfaces.

FIG3 is a block diagram of an evolved Node B (eNB) according to some embodiments. It should be noted that in some embodiments, eNB 300 may be a stationary, non-mobile device. eNB 300 may be suitable for use as eNB 104, as depicted in FIG1 . eNB 300 may include physical layer circuitry 302 and a transceiver 305, either or both of which may enable transmission and reception of signals to and from UE 200, other eNBs, other UEs, or other devices using one or more antennas 301. As an example, physical layer circuitry 302 may perform various encoding and decoding functions, including forming baseband signals for transmission and decoding received signals. As another example, transceiver 305 may perform various transmission and reception functions (e.g., conversion of signals between baseband and radio frequency (RF) ranges). Thus, physical layer circuitry 302 and transceiver 305 may be separate components or may be part of a combined component. Furthermore, some of the functions described with respect to signal transmission and reception may be performed by a combination of one, any, or all of the components or layers that may include physical layer circuitry 302, transceiver 305, and other components or layers. The eNB 300 may also include medium access control (MAC) layer circuitry 304 for controlling access to the wireless medium. The eNB 300 may also include processing circuitry 306 and memory 308, which are configured to perform the operations described herein. The eNB 300 may also include one or more interfaces 310, which may enable communication with other components, including other eNBs 104 ( FIG. 1 ), small cell APs 106, components within the EPC 120 ( FIG. 1 ), or other network components. Furthermore, the interfaces 310 may enable communication with other components that may not be shown in FIG. 1 , including components external to the network. The interfaces 310 may be wired, wireless, or a combination thereof.

FIG4 is a block diagram of a small cell access point (AP) according to some embodiments. Small cell AP 400 may include physical layer circuitry 402 and a transceiver 405, either or both of which may enable signals to be transmitted and received from UE 200, eNB 300, other eNBs, other UEs, or other devices using one or more antennas 401. As an example, physical layer circuitry 402 may perform various encoding and decoding functions, which may include forming baseband signals for transmission and decoding received signals. As another example, transceiver 405 may perform various transmission and reception functions (e.g., conversion of signals between baseband and radio frequency (RF) ranges). Thus, physical layer circuitry 402 and transceiver 405 may be separate components or may be part of a combined component. Furthermore, some of the functions described with respect to signal transmission and reception may be performed by a combination that may include one, any, or all of the physical layer circuitry 402, transceiver 405, and other components or layers. The small cell AP 400 may also include a medium access control layer (MAC) circuit 404 for controlling access to the wireless medium. The small cell AP 400 may also include processing circuitry 406 and memory 408, which are arranged to perform the operations described herein. The small cell AP 400 may also include one or more interfaces 410, which may enable communication with other components (including other eNBs 104 (Figure 1), components in the EPC 120 (Figure 1), or other network components). In addition, the interface 410 may enable communication with other components that may not be shown in Figure 1 (including components external to the network). The interface 410 may be wired, wireless, or a combination thereof.

Antennas 210, 301, 401 may include one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas, or other types of antennas suitable for transmitting RF signals. In some multiple-input multiple-output (MIMO) embodiments, antennas 210, 301, 401 may be effectively separated to exploit spatial diversity and potentially different channel characteristics.

In some embodiments, the UE 200 and/or the eNB 300 and/or the small cell AP 400 may be a mobile device and may be a portable wireless communication device, such as a personal digital assistant (PDA), a laptop or portable computer with wireless communication capabilities, a web tablet, a wireless phone, a smartphone, a wireless headset, a pager, an instant messaging device, a digital camera, an access point, a television, a wearable device (e.g., a medical device (e.g., a heart rate monitor, a blood pressure monitor, etc.)), or other device that can receive and/or send information wirelessly. In some embodiments, the UE 200 and/or the eNB 300 and/or the small cell AP 400 may be configured to operate in accordance with 3GPP standards, but the scope of the embodiments is not limited in this respect. In some embodiments, the UE 200 and/or the eNB 300 and/or the small cell AP 400 may be configured to operate in accordance with one or more IEEE 802.11 standards and/or wireless local area network (WLAN) standards, but the scope of the embodiments is not limited in this respect. In some embodiments, the mobile device or other device may be configured to operate in accordance with other protocols or standards, including IEEE 802.11 or other IEEE standards. In some embodiments, the UE 200, eNB 300, small cell AP 400, or other device may include one or more of a keyboard, a display, a non-volatile memory port, multiple antennas, a graphics processor, an application processor, a speaker, and other mobile device components. The display may be an LCD screen including a touch screen.

Although UE 200, eNB 300, and small cell AP 400 are each shown as having several separate functional elements, one or more of the functional elements may be combined and may be implemented by a combination of software-configured elements (e.g., a processing element including a digital signal processor (DSP)) and/or other hardware elements. For example, some elements may include one or more microprocessors, DSPs, field programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), radio frequency integrated circuits (RFICs), and a combination of various hardware and logic circuits for performing at least the functions described herein. In some embodiments, a functional element may refer to one or more processes operating on one or more processing elements.

Embodiments may be implemented in one or a combination of hardware, firmware, and software. Embodiments may also be implemented as instructions stored on a computer-readable storage device, which may be read and executed by at least one processor to perform the operations described herein. A computer-readable storage device may include any non-transient mechanism for storing information in a machine (e.g., computer) readable form. For example, a computer-readable storage device may include a read-only memory (ROM), a random access memory (RAM), a magnetic disk storage medium, an optical storage medium, a flash memory device, and other storage devices and media. Some embodiments may include one or more processors and may be configured with instructions stored on a computer-readable storage device.

It should be noted that in some embodiments, the apparatus used by UE 200 and/or eNB 300 and/or small cell AP 400 may include the various components of UE 200 and/or eNB 300 and/or small cell AP 400 shown in Figures 2-4. Therefore, the techniques and operations described herein involving UE 200 (or 102) may be applicable to the apparatus of a UE. Furthermore, the techniques and operations described herein involving eNB 300 (or 104) may be applicable to the apparatus of an eNB. Furthermore, the techniques and operations described herein involving small cell AP 400 (or 106) may be applicable to the apparatus of a small cell AP.

According to some embodiments, UE 102 may receive an access point reference signal (APRS) from one or more small cell APs 106 and may send APRS signal quality measurements to macro cell eNB 104. UE 102 may receive a message from macro cell eNB 104 indicating that UE 102 is to determine candidate pencil cells for signal quality measurements, the candidate pencil cells being supported by small cell APs 106. UE 102 may receive beam reference signals (BRS) for candidate pencil cells from small cell APs 106 and may refrain from receiving BRS for pencil cells not included in the message. In some cases, the beamwidth of the APRS may be greater than the beamwidth of the BRS. These embodiments are described in more detail below.

FIG5 illustrates an example scenario in which a UE can communicate with a macrocell eNB and with multiple small cell APs according to some embodiments. While the example scenario 500 shown in FIG5 may illustrate some or all aspects of the techniques disclosed herein, it should be understood that the embodiments are not limited to the example scenario 500. It should also be noted that the embodiments are not limited to the components shown in the example scenario 500. The embodiments are also not limited to the number of components shown in FIG5 or the arrangement of the components shown. As an example, the embodiments are not limited to the use of UE 102, as other mobile devices may be used in some cases. For example, a station (STA) arranged to communicate using a wireless local area network (WLAN) protocol (or other protocols) may be used. As another example, the embodiments are not limited to the use of eNB 104 (or the macrocell eNB 104 shown), as other base stations may be used in some cases. As another example, the embodiments are not limited to the use of small cell AP 106, as other base station components or other components may be used in some cases.

In example scenario 500, UE 102 may exchange packets, signals, and/or messages with eNB 104 using any suitable communication protocol (which may or may not be included as part of one or more standards). As a non-limiting example, in some cases, UE 102 may be arranged to communicate with eNB 104 using a 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) protocol. UE 102 may also exchange packets, signals, and/or messages with small cell AP 106 using any suitable communication protocol (which may or may not be the same protocol used for communication with eNB 104). For example, in some cases, UE 102 may be arranged to communicate with small cell AP 106 using a fifth generation (5G) protocol and/or an IEEE 802.11 protocol.

Furthermore, in example scenario 500, small cell AP 106 may communicate with eNB 104 and/or other network components using any suitable links and/or interfaces (which may be wireless or wired, or a combination thereof). As an example, backend communication between small cell AP 106 and MME 122 and/or eNB 104 may be used. For example, small cell AP 106 may be notified of configuration information related to communication between small cell AP 106 and UE 102.

In example scenario 500, in some cases, the eNB 104 can be configured to operate as a macro cell eNB 104 (or macro eNB 104). Accordingly, the coverage area 505 of the eNB 104 can include or overlap one or more coverage areas of the small cell AP 106. As a non-limiting example, the small cell AP 106 can be installed on a building. As shown in Figure 5, the UE 102 can physically move along a path that can include points A-D. The first small cell AP 106 labeled "S1" can support transmissions according to multiple pen cells (e.g., multiple pen cells labeled 510). The second small cell AP 106 labeled "S2" can support transmissions according to multiple pen cells (e.g., multiple pen cells labeled 520). In a similar manner, the other small cell APs 106 labeled S3-S12 can support transmissions according to the multiple pen cells shown.

When UE 102 is located at point A, UE 102 may be in coverage of small cell APs S1 and/or S2. Accordingly, one or more of pencil cells 510 and/or 520 may be able to provide directional narrow beam high-gain coverage to UE 102 based on the physical layout of small cell APs S1 and/or S2, the location of UE 102, and/or other factors (e.g., obstacles or other factors in the environment). Similarly, point B may be in coverage of small cell APs S3, S4, and/or S5, point C may be in coverage of small cell APs S7, S8, and/or S9, and point D may be in coverage of small cell APs S10 and/or S11. Accordingly, the optimal set of pencil cells and/or the optimal set of small cell APs 106 for UE 102 may change as UE 102 moves.

It should also be noted that in some embodiments, coordinated multi-point transmission (CoMP) techniques and/or multiple connectivity techniques may be used. As an example, signals may be transmitted from one or more small cell APs 106 and/or pencil cells to a UE 102 in a manner that enables diversity gain at the UE 102. For example, the same data packet may be transmitted from two or more different pencil cells for reception at the UE 102, which may utilize diversity combining or other techniques for receiving multiple copies of the data packet.

As a non-limiting example, in scenarios such as 500 and/or others, millimeter wave (mmW) small cells may be deployed in the coverage of macro cells operating below 6 GHz. This operation may be applicable to the heterogeneous network structure of future 5G mobile systems and/or other systems. In some cases, the mmW small cell AP 106 may use a pencil beam with a relatively narrow beam width (e.g., 5 to 15 degrees) and a relatively high antenna gain and/or beamforming gain to achieve link budget targets and energy-efficient communication. Each pencil beam may be viewed as a pencil cell that can be detected by a dedicated signature signal sequence for the pencil cell. In an environment where mmW small cells are ultra-densely deployed, for example, it may be possible or probable that multiple pencil beams that may experience different path losses may reach the UE 102. The beam may originate from one or more mmW small cell APs 106. In some cases, in order to establish a reliable, energy-efficient, and/or high-data-rate communication path between a mmW UE 102 and a radio access network (RAN), it may be beneficial to select and allocate an optimal set of pencil beams to serve the UE 102. Due to the mobility of the mmW UE 102 and changes in the surrounding environment, it is possible that the optimal set of pencil beams may change depending on the dynamics of the propagation channel between the UE 102 and the small cell AP 106. Therefore, components of the RAN (e.g., macro cell eNB 104) may track these dynamics in order to provide consistent high-data-rate service to the UE 102.

FIG6 illustrates the operation of a method of communication according to some embodiments. It is important to note that embodiments of method 600 may include additional or even fewer operations or processes than those shown in FIG6 . Furthermore, embodiments of method 600 are not necessarily limited to the chronological order shown in FIG6 . In describing method 600, reference may be made to FIG1-FIG5 and FIG7-FIG11 , but it should be understood that method 600 may be practiced with any other suitable systems, interfaces, and components.

Furthermore, while the method 600 and other methods described herein may involve an eNB 104 or UE 102 operating in accordance with 3GPP or other standards, embodiments of these methods are not limited to only these eNBs 104 or UEs 102 and may also be practiced on other devices (e.g., Wi-Fi access points (APs) or subscriber stations (STAs)). The method 600 and other methods described herein may also involve a small cell AP 106 (or other AP 106) that may operate in accordance with one or more IEEE 802.11 standards, WiGIG standards, 5G standards, or other standards, but embodiments of those methods are not limited to use of the AP 106 and/or operation in accordance with those standards. For example, in some cases, other base station components may be configured to operate as a small cell base station.

Furthermore, method 600 and other methods described herein may be practiced by wireless devices configured to operate in other suitable types of wireless communication systems, including systems configured to operate in accordance with various IEEE standards (e.g., IEEE 802.11). Method 600 may also involve the apparatus of UE 102 and/or eNB 104 and/or small cell AP 106 and/or other devices described above.

At operation 605 of method 600, UE 102 may receive one or more small cell AP control messages from macro cell eNB 104. In some embodiments, the small cell AP control message may include one or more small cell APs 106 from which UE 102 is to receive one or more access point reference signals (APRS). As an example, the small cell AP control message may include information related to the APRS and/or the small cell AP 106. This information may include, but is not limited to, a signature sequence for the APRS, an identifier of the small cell AP 106 from which the APRS is to be received, channel resources to be used for reception, timing at which the APRS is to be received, and/or other suitable information. In some embodiments, the small cell AP control message may include a "small cell search request," which may request UE 102 to determine a small cell signal quality measurement based on reception of the APRS.

Furthermore, it should be noted that embodiments are not limited to the use of small cell AP control messages, as other control messages and/or other messages may be used for conveying such information related to the APRS and/or small cell AP 106. For example, such information may be included in other messages that may or may not be dedicated to conveying information.

In some embodiments, the eNB 104 may be configured to operate as a macrocell eNB 104. As an example, the coverage area of the macrocell eNB 104 may be larger than the combined coverage area including the coverage area of the small cell AP 106. In other words, the coverage area of the small cell AP 106 may be a sub-area of the coverage area of the macrocell eNB 104. However, this example is not limiting. In some cases, one or more small cell coverage areas (or portions thereof) may not necessarily be included in the macrocell coverage area.

At operation 610, the UE 102 may receive one or more APRSs from one or more small cell APs 106. In some embodiments, the APRS may be received from the small cell AP 106 indicated in the previously described small cell AP control message, but the embodiment is not limited thereto.

It should be noted that in some embodiments, signals (e.g., small cell AP control messages and/or other) may be received from eNB 104 in a first channel resource, which may be different from and/or not include a second channel resource used to receive other signals (e.g., APRS) from small cell AP 106. As a non-limiting example, the first and second channel resources may both be located at centimeter wave (cmW) frequencies, which may be different in some cases. As another non-limiting example, in some cases, the frequency bands used for communication with eNB 104 and for communication with small cell AP 106 may not overlap.

As an example, the small cell AP 106 can transmit APRS in an omnidirectional manner. As another example, a beam width of 120, 90, or 45 degrees can be used. However, these examples are not limiting, as other suitable beam widths can be used for APRS transmission.

At operation 615, UE 102 may send one or more AP signal quality measurements to eNB 104. In some embodiments, the measurements may be based on receiving APRS at UE 102. For example, in some cases, UE 102 may receive APRS and may perform measurements. The AP signal quality measurements may include any suitable measurements (e.g., received signal strength indication (RSSI), reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-noise ratio (SNR), signal-to-interference plus noise ratio (SINR), and/or any suitable measurement related to the received APRS). In some cases, these measurements may be included in one or more standards, but embodiments are not limited thereto. The AP signal quality measurements may be sent in one or more control messages or other messages that may or may not be dedicated for these purposes.

In some embodiments, AP signal quality measurements may enable the eNB 104 to determine which small cell APs 106 may be in the vicinity of the UE 102 and/or which small cell APs 106 may have strong wireless links with the UE 102 .

At operation 620, the UE 102 may receive one or more pencil cell control messages from the eNB 104 that may indicate one or more candidate pencil cells for which the UE 102 is to determine signal quality measurements. At operation 625, the UE 102 may receive beam reference signals (BRSs) for the candidate pencil cells from the small cell AP 106. At operation 630, the UE 102 may refrain from receiving BRSs from the small cell AP 106 for the pencil cells not included in the pencil cell control message. In some cases, the UE 102 may refrain from receiving BRSs from the small cell AP 106 for the pencil cells excluded from the pencil cell control message. In some embodiments, the pencil cell control message may include a "pencil cell search request," which may request the UE 102 to determine pencil cell signal quality measurements based on reception of the BRSs.

It should be noted that the indication of candidate pencil cells and/or BRSs that the UE 102 is to receive may enable the UE 102 to perform measurements on a relatively small number (or a manageable number) of pencil cells. That is, the indicated candidate pencil cells may be a subset of the total number of pencil cells supported by the small cell AP 102. In some cases, the UE 102 may benefit from not having to receive BRSs and perform measurements on the full number of pencil cells.

In some embodiments, the pen cell control message may include information related to the BRS and/or the pen cell and/or the small cell AP 106. This information may include, but is not limited to, a signature sequence for the BRS, an identifier of the pen cell and/or small cell AP 106 from which the BRS is to be received, channel resources to be used for reception, timing at which the BRS is to be received, and/or other suitable information. Furthermore, it should be noted that embodiments are not limited to the use of the pen cell control message, as other control messages and/or other messages may be used to convey such information. For example, such information may be included in other messages that may or may not be dedicated to conveying information.

As described herein, in some cases, the small cell AP 106 can support multiple pen cells. In some embodiments, the coverage area of the APRS for the small cell AP 106 can be larger than the combined coverage area including the coverage areas of the BRS for multiple pen cells supported by the small cell AP 106. As a non-limiting example, a portion of the coverage area of the APRS (which in some cases may be referred to as "small cell coverage") can be divided into smaller cells, which can be used by the small cell AP 106 for directional high-gain communication with the UE 102 in a relatively small and/or narrow area. That is, one or more coverage areas of the pen cell can be sub-areas of the coverage area of the small cell AP 106. However, this example is not limiting. In some cases, one or more pen cell coverage areas (or portions thereof) may not necessarily be included in the coverage area of the small cell AP 106.

Accordingly, a relatively narrow beam width can be used by the small cell AP 106 for transmission according to the pencil cell. That is, directional transmission using beamforming technology and/or other technologies can be used for transmission according to the pencil cell. For example, the beam width used for transmission according to the pencil cell can be narrower than the beam width used for transmission of the APRS. As a non-limiting example, the beam width for the APRS can be at least 90 degrees, and the beam width for the pencil cell can be at most 15 degrees. As another non-limiting example, the beam width for the pencil cell can be included in the range of 5 to 15 degrees. As another non-limiting example, the APRS can be transmitted in an omnidirectional manner.

In addition, beamforming gain and/or other gains may be applied to transmissions based on the pencil cell. As a non-limiting example, a 10 dB gain may be used to perform BRS transmissions by the small cell AP 106 compared to APRS transmissions. However, embodiments are not limited to a 10 dB gain, as 5, 15, 20 dB, or other suitable values may be used in some cases.

In some embodiments, at least one small cell AP 106 may support multiple different candidate pen cells for which the BRS is assigned. For example, the signature sequence on which the BRS is based may be different for different pen cells. In some cases, this difference may enable the UE 102 to identify which pen cell the small cell AP 106 is using for transmission. It should also be noted that the pen cell control message may indicate candidate pen cells that the same small cell AP 106 may or may not support. As an example, some candidate pen cells may be supported by different small cell APs 106. For example, the UE 102 may be located on the edge of coverage between two small cell APs 106, and the eNB 104 may identify one or more pen cells from each of two different small cell APs 106 that may be candidates for use by the UE 102. 5 , when the UE 102 is located at point A, one or more pencil cells 510 supported by the “S1” small cell AP 106 and one or more pencil cells 520 supported by the “S2” small cell AP 106 may be candidate pencil cells for the UE 102. As another example, in some cases, some or all of the candidate pencil cells may be supported by the same small cell AP 106.

At operation 635, the UE 102 may send the pencil cell signal quality measurements to the eNB 104. In some embodiments, the measurements may be based on receiving a BRS at the UE 102. For example, in some cases, the UE 102 may receive a BRS and may perform measurements. The pencil cell signal quality measurements may include any suitable measurements (e.g., received signal strength indication (RSSI), reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-noise ratio (SNR), signal-to-interference and noise ratio (SINR), and/or any suitable measurements related to the received APRS). In some cases, these measurements may be included in one or more standards, but the embodiments are not limited thereto. The pencil cell signal quality measurements may be sent in one or more control messages or other messages that may or may not be dedicated to these purposes. In some embodiments, the pencil cell signal quality measurements may enable the eNB 104 to determine which pencil cells may be near the UE 102 and/or which small cell APs 106 may have a strong wireless link with the UE 102.

At operation 640, UE 102 may receive one or more pencil cell configuration messages from eNB 104. In some embodiments, the message may instruct eNB 104 to select a candidate pencil cell for exchanging data messages with UE 102. At operation 645, UE 102 may receive a data message from a corresponding small cell AP 106 supporting the selected candidate pencil cell based on the selected candidate pencil cell. In other words, UE 102 may begin receiving data from the corresponding small cell AP 106 based on the selected candidate pencil cell.

In some embodiments, UE 102 may continue to perform measurements on APRS and/or BRS in order to monitor the signal quality from the pen cell and/or small cell AP 106. As an example, UE 102 may send these measurements in a periodic manner according to a periodic parameter (in some cases, they may be updated measurements). As another example, UE 102 may send measurements in an aperiodic manner. For example, in some cases, eNB 104 may request measurements. As another example, eNB 104 may notify UE 102 of a new set of candidate pen cells on which UE 102 will perform measurements. As another example, eNB 104 may instruct UE 102 to switch to another pen cell. In some cases, the pen cell to which UE 102 is to switch may be included in the group of initial candidate pen cells (e.g., as indicated in operation 620) and/or the group of new candidate pen cells, but the embodiment is not limited thereto. As another example, the eNB 104 may instruct the UE 102 to reconfigure from the selected candidate pencil cell to the reconfigured candidate pencil cell for exchanging data messages with the UE 102. The UE 102 may receive data messages from the corresponding small cell AP supporting the reconfigured candidate pencil cell based on the reconfigured candidate pencil cell. It should be noted that the embodiments are not limited to these example operations related to handover and/or reconfiguration, as other operations may be used in some cases in addition to or instead of the operations just described.

In some embodiments, different channel resources may be used for different communications performed by the UE 102. As a non-limiting example, the UE 102 may exchange control messages with the eNB 104 using macro cell channel resources at a first centimeter wave (cmW) frequency. The UE 102 may receive an APRS from the small cell AP 106 in the small cell channel resources at a second cmW frequency. The small cell channel resources may be different from the macro cell channel resources, not include the macro cell channel resources, and/or not overlap with the macro cell channel resources. The UE 102 may receive a BRS from the small cell AP 106 based on candidate pencil cells in the pencil cell channel resources at a millimeter wave (mmW) frequency. Accordingly, the pencil cell channel resources may be different from the macro cell channel resources and the small cell channel resources, not include the macro cell channel resources and the small cell channel resources, and/or not overlap with the macro cell channel resources and the small cell channel resources. In some cases, the UE 102 may receive data from the small cell AP 106 using channel resources according to the selected candidate pencil cells at a mmW frequency, which may or may not be the same mmW frequency used to receive the BRS.

It should be noted that in some cases, various techniques and/or designs may enable UE 102 to transmit and/or receive signals in multiple frequency bands. As an example, UE 102 may use a set of one or more antennas to transmit and/or receive signals in different frequency bands. It should be understood that in some such arrangements, additional components (e.g., a duplexer or other components) may be included. As another example, one or more antennas may be dedicated to each frequency band for transmission and/or reception. However, these examples are not limiting, as any suitable technique may be used in these and other scenarios to accommodate UE 102's use of multiple frequency bands.

FIG7 illustrates another example of a method for communication according to some embodiments. As previously described with respect to method 600, embodiments of method 700 may include additional or even fewer operations or processes than those shown in FIG7 , and embodiments of method 700 are not necessarily limited to the chronological order shown in FIG7 . In describing method 700, reference may be made to FIG1-6 and FIG8-11 , but it should be understood that method 700 may be practiced using any other suitable systems, interfaces, and components. Furthermore, embodiments of method 700 may also be applicable to UE 102, eNB 104, small cell AP 106, AP, STA, or other wireless or mobile device. Method 700 may also involve apparatus of small cell AP 106, eNB 104, and/or UE 102 and/or other devices described above.

It should be noted that method 700 can be practiced at eNB 104 and can include exchanging signals or messages with UE 102. Similarly, method 600 can be practiced at UE 102 and can include exchanging signals or messages with eNB 104. In some cases, the operations and techniques described as part of method 600 can be related to method 700. Furthermore, embodiments can include operations performed at eNB 104 that are reciprocal or similar to other operations described herein performed at UE 102. For example, the operations of method 700 can include eNB 104 sending a message, while the operations of method 600 can include UE 102 receiving the same or a similar message.

Furthermore, in some cases, the previous discussions of various techniques and concepts may be applicable to method 700, including macro cell arrangements and devices, small cell arrangements and devices, pencil cell arrangements and devices, APRS, BRS, control messages, beamforming, and others.

At operation 705, the eNB 104 may send a small cell measurement request to the UE 102 indicating one or more small cell APs 106 for which the UE 102 is to determine small cell signal quality measurements. At operation 710, the eNB 104 may receive the small cell signal quality measurements from the UE 102. Although embodiments are not limited in this regard, in some cases, the previously described techniques for indicating the small cell APs 106 may be used, and the previously described signal quality measurements may be used.

At operation 715, the eNB 104 may determine a set of candidate pencil cells for which the UE 102 will determine pencil cell signal quality measurements. At operation 720, the eNB 104 may send a pencil cell measurement request indicating the set of candidate pencil cells to the UE 102. The candidate pencil cells may be determined from the pencil cells supported by the small cell AP 106. In some embodiments, the eNB 104 may determine that the candidate pencil cells in the set may be possible candidates for pencil cell reception of data by the UE 102. As an example, the determination may be based at least in part on the received small cell signal quality measurements. For example, a pencil cell of a small cell AP 106 with a relatively strong small cell signal quality measurement may be determined as a candidate. As another example, the determination may be based on the geographical layout of the pencil cells and the directional beam pattern of the pencil cells. For example, such geographical information may be used together with the small cell signal quality measurements in determining the candidate pencil cells.

At operation 725, the eNB 104 may receive a pencil cell signal quality measurement from the UE 102. In some embodiments, the received pencil cell signal quality measurement may be for a candidate pencil cell indicated in the pencil cell measurement request. As a non-limiting example, the signal quality measurement previously described may be used. The measurement may be received from the UE 102 in one or more control messages or other messages that may or may not be dedicated to conveying signal quality measurements.

At operation 730, the eNB 104 may select a candidate pencil cell from the set of candidate pencil cells for use by the UE 102. At operation 735, the eNB 104 may send an indicator of the selected candidate pencil cell to the UE 102. It should also be noted that the selected candidate pencil cell and/or related information may also be communicated to one or more small cell APs 106 (e.g., a specific small cell AP 106 supporting the selected candidate pencil cell) using techniques such as those previously described. For example, the MME 122 and/or the eNB 104 may communicate such information via a backhaul and/or other interface.

As an example, the selection may be based at least in part on a pencil cell signal quality measurement. As another example, the selection may also be based at least in part on geographic information (e.g., the geographic layout information described previously). As another example, the selection may be further based at least in part on the small cell signal quality measurement received at operation 710. Thus, the eNB 104 may use any combination of this information to select the pencil cell that the UE 102 will use to receive data. However, these examples are not limiting, as other information may be used in the selection in addition to or in place of the information described in these examples.

As a non-limiting example, a measurement request is sent in a macro cell channel resource at a first centimeter wave (cmW) frequency. The small cell signal quality measurement may be based on a signal sent by the small cell AP 106 in the small cell channel resource at a second cmW frequency. The pencil cell signal quality measurement may be based on a directional signal sent by the small cell AP 106 in the pencil cell channel resource at a millimeter wave (mmW) frequency.

FIG8 shows an example of communication between a UE and a macrocell eNB according to some embodiments. It should be noted that embodiments are not limited to the example communication 800 shown in FIG8 with respect to the number, arrangement, or type of components or messages. As an example, some embodiments may include or may not include all messages and/or operations shown in the example communication 800 in FIG8 . Some methods described herein may include some or all of these operations and/or similar operations, but embodiments are not limited thereto. In addition, other mobile device components and/or base station components may be used in some cases. In some cases, the previous discussion of various techniques and concepts may be applicable to the example communication 800, including macrocell arrangements and equipment, small cell arrangements and equipment, pen cell arrangements and equipment, APRS, BRS, control messages, beamforming, and others.

At operation 805, eNB 104 may configure a list of APRSs to be measured and reported by UE 102 and may deliver the list to UE 102. UE 102 may detect and measure the APRSs included in the list at operation 810 and may periodically report RSRP/RSRQ and/or other APRS-related measurements to eNB 104 at operation 815. At operation 820, eNB 104 may select multiple pen cells that may be associated with strongly received APRSs for measurement by UE 102. At operation 825, eNB 104 may configure a list of BRSs to be measured and reported. In some cases, the BRSs may be those assigned to the pen cells determined at operation 820. At operation 830, UE 102 may detect and measure the indicated BRSs and may periodically report RSRP/RSRQ and/or other BRS-related measurements to eNB 104 at operation 835. At operation 840, the eNB may use any suitable technique to select a plurality of pencil cells with stronger reception, examples of which are described below. At operation 845, the eNB 104 may configure the selected pencil cells as secondary member cells and may communicate this information to the UE 102. At operation 850, the UE 102 may monitor the configured pencil cells for data packets.

At operations 855-870, the eNB 104 and the UE 102 may perform similar operations to possibly select a new set of secondary pencil cells. For example, to accommodate the mobility of the UE 102, in some cases, it may be beneficial or necessary to use new pencil cells with different locations and/or orientations.

FIG9 illustrates another example of a method for communication according to some embodiments. As previously described with respect to methods 600 and 700, embodiments of method 900 may include additional or even fewer operations or processes than those shown in FIG9 , and embodiments of method 900 are not necessarily limited to the chronological order shown in FIG9 . In describing method 900, reference may be made to FIG1-8 and FIG10-11 , but it should be understood that method 900 may be practiced with any other suitable systems, interfaces, and components. Furthermore, embodiments of method 900 may also be applicable to UE 102, eNB 104, small cell AP 106, AP, STA, or other wireless or mobile device. Method 900 may also involve apparatus of small cell AP 106, eNB 104, and/or UE 102 and/or other devices described above.

It should be noted that method 900 can be practiced at the small cell AP 106 and can include exchanging signals or messages with the UE 102. Similarly, method 600 can be practiced at the UE 102 and can include exchanging signals or messages with the small cell AP 106. In some cases, the operations and techniques described as part of method 600 can be related to method 900. Furthermore, embodiments can include operations performed at the small cell AP 106 that can be reciprocal or similar to other operations described herein performed at the UE 102. For example, the operations of method 900 can include the small cell AP 106 transmitting a reference signal, while the operations of method 600 can include the UE 102 receiving the same reference signal or a similar reference signal.

Furthermore, in some cases, the previous discussion of various techniques and concepts may be applicable to method 900, including macro cell arrangements and devices, small cell arrangements and devices, pencil cell arrangements and devices, APRS, BRS, control messages, beamforming, and others.

In operation 905, the small cell AP 106 may transmit an APRS in an APRS channel resource. Although not limited thereto, the APRS may be transmitted at a centimeter wave (cmW) frequency. In operation 910, the small cell AP 106 may transmit multiple BRSs in a BRS channel resource. Although not limited thereto, the BRS may be transmitted at a millimeter wave (mmW) frequency. In some embodiments, the BRSs may be assigned to multiple directional pencil cells supported by the small cell AP 106. Although not limited thereto, in some cases, the specifications (e.g., beam width) for APRS and BRS described previously may be applicable.

In operation 915, the small cell AP 106 may receive an indication that one of the pen cells is selected by the small cell AP 106 for sending a data message to the UE 102. As an example, the MME 122, the macro eNB 104, or other components may send the indication to the small cell AP 106, as previously described, but the embodiments are not limited thereto. In operation 920, the small cell AP 106 may send one or more data messages to the UE 102. In some embodiments, the transmission may be performed according to the transmission direction assigned to the selected pen cell, as previously described. As an example, for the transmission of data, the BRS channel resources used for BRS transmission may also be used. However, this example is not limiting, as other channel resources may be used. Other channel resources may overlap or not overlap with the BRS channel resources in some cases, and may or may not be performed at another mmW frequency in some cases.

In some embodiments, the data message may include or may be based on the BRS for the selected pen cell.For example, the data message may include a data portion and may also include a control portion (eg, a pilot portion or other portion) that may be based on the BRS.

Figure 10 shows an example reference signal according to some embodiments. Small cell AP 1000 (which may be suitable for use as small cell AP 106 in some cases) can provide APRS coverage 1010 or small cell coverage indicated by a circular area 1015. As a non-limiting example, for APRS coverage, omnidirectional transmission or transmission with a relatively wide (e.g., 90 degrees or higher) beamwidth can be used. Small cell AP 1000 can also provide BRS coverage 1020 or pencil cell coverage indicated by an elliptical area 1025. As a non-limiting example, a narrow beamwidth can be used. For example, for a pencil cell, a range of 5-15 degrees can be used. As another non-limiting example, the coverage of the APRS transmitted by small cell AP 106 can be similar to the aggregated coverage of the pencil cell transmitted by small cell AP 106.

As an example of APRS transmission, the LTE cell-specific reference symbol (CRS) of port 0 can be used. As another example, the LTE discovery signal can be used. Accordingly, one or more synchronization signals and/or CRS of port 0 can be used. As another example, the physical side link discovery signal can be used. Accordingly, the small cell AP 106 can be configured to operate as a device that can be discovered by the UE 102, for example, when the UE 102 is in close proximity to the small cell AP 106. It should be noted that the embodiments are not limited to these examples, as other suitable technologies can be used for APRS transmission and/or APRS design. CSI-RS can be included in the 3GPP standard or other standards, but the embodiments are not limited thereto.

As an example of BRS transmission, the macro eNB 104 can configure the periodicity and/or time-frequency resources for BRS. As another example, the BRS can reuse similar technologies used for LTE discovery signals. For example, the BRS may include one or more beam-specific synchronization signals and/or channel state information reference symbols (CSI-RS). The CSI-RS may be included in the 3GPP standard or other standards, but the embodiments are not limited thereto. As another example, different BRSs for the pen-shaped cells of the same small cell AP 106 may be sent with different periodicities. For example, the BRS of a pen-shaped cell that supports more UEs 102 and/or more services may be sent more frequently than the BRS of a pen-shaped cell that supports fewer UEs 102 and/or fewer services. As another example, some or all BRSs used by the pen-shaped cells of the same small cell AP 106 may be sent simultaneously. For example, the BRSs in these cases may be sent in the same OFDM symbol period and/or time transmission interval (TTI) or other time period. In these cases, the small cell AP 106 can include multiple RF chains and/or multiple analog beamformers to support simultaneous transmission of multiple beams. As another example, the same RF chain can transmit multiple BRSs at different times. It should be noted that the embodiments are not limited to these examples, as other suitable techniques can be used for BRS transmission and/or BRS design.

FIG11 illustrates examples of transmission of reference signals according to various periodicity parameters in accordance with some embodiments. In a first example 1110, BRSs for eight pen cells (labeled BRS0-7) are transmitted according to a period T. For example, each of BRS0-BRS7 is transmitted within a set of time intervals 1115. Additional time interval groups similar to those in 1115 may be transmitted at intervals of up to T, as indicated by 1117.

In a second example 1120, BRSs for eight pen cells (labeled BRS8-15) are transmitted according to a period of 2T. For example, each of BRS8-BRS15 is transmitted within a set of time intervals 1125. Additional time interval groups similar to those in 1125 can be transmitted at intervals of up to 2T, as indicated by 1127. In a third example 1130, BRSs for eight pen cells (BRS16-23) are transmitted according to a period of 4T. For example, each of BRS16-BRS23 is transmitted within a set of time intervals 1135. Additional time interval groups similar to those in 1135 can be transmitted at intervals of up to 4T, as indicated by 1137.

As a non-limiting example, the small cell AP 106 can be configured to perform multiple BRS transmissions during time periods that may at least partially overlap. For example, the small cell AP 106 can include and/or be configured to support three analog beamformers, each of which can be used for a different pencil cell supported by the small cell AP 106. The first beamformer can be used by the small cell AP 106 to transmit BRS0-BRS7 according to example 1110. Furthermore, the second beamformer can be used to transmit BRS8-BRS15 according to example 1120, and the third beamformer can be used to transmit BRS16-BRS23 according to example 1130. Accordingly, in this example of transmitting three BRSs during overlapping time periods, the small cell AP 106 can simultaneously transmit up to three different BRSs, and can transmit the BRSs according to different periodicity parameters. It should be noted that embodiments are not limited to this example, as any suitable number of RF chains and/or analog beamformers can be used, and any suitable arrangement of BRS transmission times can also be used. For example, the periodicity parameters for each of the RF chains and/or analog beamformers may or may not be different in some arrangements. As previously described, the periodicity for each pencil cell may vary depending on the number of UEs 102 supported by the pencil cell and/or the traffic load of the pencil cell.

In some embodiments, UE 102 can perform two levels of cell detection and measurement. As an example, the first level can be used to detect and measure mmW APs 106 by searching for cmW APRS. The second level can be used to measure mmW pen cells by detecting BRS. The cell IDs of the reference signals (APRS and/or BRS) that UE 102 will search for can be determined by eNB 104 and can be signaled to UE 102. The list of beam cell IDs selected for the second level of measurement can be based on the reported measurement results of the first level of measurement.

In some embodiments, the first level of cell detection may enable the UE 102 to discover the mmW AP 106 without beam acquisition. In some cases, the second level of cell detection and measurement may be performed using only the BRS signaled by the eNB 104. Thus, in some cases, the UE 102 may not need to perform an exhaustive initial pencil cell search for all possible pencil cells from all possible mmW APs 106.

As an example, the eNB 104 can select one or more mmW pencil cells based at least in part on the reported BRS signal quality measurements. The eNB 104 can configure the selected pencil cells as secondary member cells. Accordingly, downlink beam acquisition can be inherently achieved through pencil cell allocation. In some cases, one or more mmW APs 106 can support the configured mmW pencil cells. Accordingly, in some cases, CoMP can be supported.

As an example, the number of configured secondary member cells, which may include small cell APs 106 and/or pen cells, may be greater than the number of supported secondary cells (SCells). For example, the number of supported SCells may be standard-dependent, but embodiments are not limited thereto. In these cases, the number of supported SCells may be increased (in the standard or otherwise), and/or SCells may be further aggregated with their own secondary cells. For example, these cells may be "order 2 secondary cells" or similar, depending on the hierarchical cell/carrier aggregation arrangement.

In some embodiments, any suitable technique can be used to select a pencil cell as an SCell. For example, eNB 104 can define a threshold Tbrs, and pencil cells with reported RSRP/RSRQ (or other measurements) greater than the threshold Tbrs can be selected as secondary cells. With reference to operation 840 ( FIG. 8 ), this technique may be referred to as "Method C1" in FIG. 8 .

As another example, multiple thresholds can be defined, which can help avoid frequent SCell reconfiguration due to environmental changes. For k=1,2,…K, the thresholds can be Tbrs-1, Tbrs-2,…Tbrs-K, where Tbrs-1>Tbrs-2>…Tbrs-K. Each threshold Tbrs-k can be used to define a pencil cell cluster including Bk adjacent pencil cells centered on a pencil cell with a reported RSRP/RSRQ measurement greater than Tbrs-k. It is reasonable to define B1>B2>…>Bk. The variable p_j (for j=1,…L) can define the L BRSs reported by UE 102 to eNB 104, each of which has a reported RSRP/RSRQ greater than one of the thresholds Tbrs-k. eNB 104 can select L pencil cell clusters defined as P_i (where i=1,…L) as secondary cells for UE 102. That is, P_i may include multiple adjacent beam cells centered around the pencil cell p_i, and the number of pencil cells in P_i may depend on the threshold over which the reported RSRP/RSRQ is greater. In some cases, the pencil cells other than the p_i included in P_i may be referred to as "guard beams." With reference to operation 840 ( FIG. 8 ), this technique may be referred to as "Method C2" in FIG. 8 . It should be noted that some embodiments may include one or more of the operations and/or techniques described in this example, and some embodiments may include additional operations and/or techniques.

As another example, the secondary member pen cell can be reconfigured to support mobility. When the updated APRS and/or BRS signal quality measurements are reported from the moving or mobile UE 102 to the eNB 104, the eNB 104 can perform reconfiguration and/or reselection of the secondary member cell. As previously described, a protection beam can be used. In addition, in some cases, the protection beam can potentially become an "anchor beam" for which the reported RSRQ/RSRP (or other measurements) can be greater than a defined threshold. A currently configured set of secondary pen cells can be defined as P_current. Based on the updated BRS signal quality measurements, a set of new pen cells P_new can be determined using the previously described techniques and/or other techniques. The intersection P_work may include the intersection of the set P_current and the set P_new. A set of selection metrics O_current and O_new can be determined for the set P_current and the set P_new, respectively. As a non-limiting example of this case, each selected pen cell in the set can be given a weighting factor based on its reported signal quality measurement. In addition, in some cases, some unreported pen cells may be given a predetermined minimum weight factor. As an example, when the ratio of O_current to O_new is less than a certain threshold T (which may or may not be predetermined), beam cell reconfiguration may be performed. However, this example is not limiting, as other suitable comparison operations and/or other operations may be performed on the sets O_current and O_new to determine whether beam cell reconfiguration is to be performed. With reference to operation 865 ( FIG. 8 ), this technique may be referred to as “Method R1” in FIG. 8 . It should be noted that some embodiments may include one or more of the operations and/or techniques described in this example, and some embodiments may include additional operations and/or techniques.

It should be noted that in some cases, the conversion and/or switching of the pen cell can be inherently implemented as a result of the reconfiguration method. It should be noted that in some embodiments, one or more operations included in the example just described (e.g., reconfiguration of the secondary member pen cell and selection of the pen cell as the SCell) can be included, including but not limited to methods 600, 700, and 900 and scenario 800 shown in Figure 8.

In Example 1, an apparatus for a user equipment (UE) may include a transceiver circuit and a hardware processing circuit. The hardware processing circuit may configure the transceiver circuit to receive one or more access point reference signals (APRS) from one or more small cell access points (APs). The hardware processing circuit may further configure the transceiver circuit to send one or more AP signal quality measurements to a macro cell evolved node B (eNB) based on the reception of the APRS. The hardware processing circuit may further configure the transceiver circuit to receive a pen cell control message from the macro cell eNB indicating one or more candidate pen cells for which the UE is to determine signal quality measurements, the candidate pen cells being supported by small cell APs. The hardware processing circuit may further configure the transceiver circuit to receive a beam reference signal (BRS) from the small cell AP for the candidate pen cells.

In Example 2, the subject matter of Example 1, the hardware processing circuitry further configures the transceiver circuitry to refrain from receiving a BRS from the small cell AP for a pen cell not included in the pen cell control message.

In Example 3, the subject matter of one or any combination of Examples 1-2, wherein the beamwidth of the APRS can be greater than the beamwidth of the BRS.

In Example 4, the subject matter of one or any combination of Examples 1-3, wherein the beamwidth of the APRS can be at least 90 degrees and the beamwidth of the BRS can be at most 15 degrees.

In Example 5, the subject matter of one or any combination of Examples 1-4, wherein, for at least one small cell AP, the coverage area of the APRS for the small cell AP may be larger than the combined coverage area including the coverage areas of the BRSs for multiple pen cells supported by the small cell AP.

In Example 6, the subject matter of any one or any combination of Examples 1-5, wherein the pen cell control message may be received in a macro cell channel resource at a first centimeter wave (cmW) frequency. The APRS may be received in a small cell channel resource at a second cmW frequency. The BRS may be received in a pen cell channel resource at a millimeter wave (mmW) frequency.

In Example 7, the subject matter as described in any one or any combination of Examples 1-6, wherein the coverage area of the macro cell eNB may be larger than a combined coverage area including the coverage area of the small cell AP.

In Example 8, the subject matter as described in one or any combination of Examples 1-7, wherein at least some of the candidate pencil cells may be supported by different small cell APs.

In Example 9, the subject matter as described in one or any combination of Examples 1-8, wherein at least some of the candidate pencil cells may be supported by the same small cell AP.

In Example 10, the subject matter as described in any one or any combination of Examples 1-9, wherein at least one small cell AP can support a plurality of different candidate pencil cells for which the BRSs are assigned.

In Example 11, the subject matter of one or any combination of Examples 1-10, wherein the hardware processing circuitry further configures the transceiver circuitry to transmit a pen cell signal quality measurement to the macro cell eNB based on reception of the BRS. The hardware processing circuitry may further configure the transceiver circuitry to receive a pen cell configuration message from the macro cell eNB indicating one of the candidate pen cells selected by the macro cell eNB for exchanging data messages with the UE. The hardware processing circuitry may further configure the transceiver circuitry to receive a data message from a corresponding small cell AP supporting the selected candidate pen cell based on the selected candidate pen cell.

In Example 12, the subject matter of one or any combination of Examples 1-11, the hardware processing circuitry configures the transceiver circuitry to send an updated pen cell signal quality measurement about the candidate pen cell to the macro cell evolved Node B (eNB). The hardware processing circuitry may further configure the transceiver circuitry to receive a pen cell reconfiguration message from the macro cell eNB, the pen cell reconfiguration message indicating a reconfiguration of the UE from the selected candidate pen cell to a candidate pen cell reconfigured for exchanging data messages with the UE. The hardware processing circuitry may further configure the transceiver circuitry to receive a data message from a corresponding small cell AP that supports the reconfigured candidate pen cell based on the reconfigured candidate pen cell.

In Example 13, the subject matter of one or any combination of Examples 1-12, the hardware processing circuitry further configures the transceiver circuitry to receive a small cell AP control message from the macro cell eNB indicating the small cell AP from which the UE is to receive the APRS.

In Example 14, the subject matter of one or any combination of Examples 1-13, wherein the pen cell control message may further indicate a BRS assigned to the candidate pen cell.

In Example 15, the subject matter as described in one or any combination of Examples 1-14, wherein the UE may be arranged to operate in accordance with a 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) protocol to exchange messages with the macro eNB.

In Example 16, the subject matter of one or any combination of Examples 1-15, wherein the apparatus may further include: one or more antennas coupled to the transceiver circuitry for receiving the pen control message and transmitting the AP signal quality measurement.

In Example 17, a non-transitory computer-readable storage medium may store instructions that are executed by one or more processors to perform operations for a user equipment (UE) to communicate. The operations may configure the one or more processors to receive a request from a macro cell evolved node B (eNB) to determine a small cell signal quality measurement based on an access point reference signal (APRS) received at the UE from one or more small cell access points (APs). The operations may further configure the one or more processors to send the small cell signal quality measurement determined by the UE to the macro cell eNB. The operations may further configure the one or more processors to receive a request from the macro cell eNB to determine a pen cell signal quality measure for a set of candidate pen cells supported by at least a portion of the small cell APs. The pen cell signal quality measurement may be based on receiving a directional beam reference signal (BRS) from the small cell AP at the UE based on the candidate pen cells.

In Example 18, the subject matter of Example 17, the operations may further configure the one or more processors to: receive a BRS from the small cell AP based on a pen cell included in the set of candidate pen cells. The operations may further configure the one or more processors to: suppress receiving a BRS from the small cell AP based on a pen cell not included in the set of candidate pen cells.

In Example 19, the subject matter of one or any combination of Examples 17-18, wherein the operations further configure the one or more processors to send the pencil cell signal quality measurement determined by the UE to the macro cell eNB. The operations may further configure the one or more processors to receive, from the macro cell eNB, an indicator of a candidate pencil cell selected by the eNB for exchanging data messages with the UE. The operations may further configure the one or more processors to, based on the selected candidate pencil cell, receive a data message from a corresponding small cell AP supporting the selected candidate pencil cell.

In Example 20, the subject matter of any one or any combination of Examples 17-19, wherein for receiving the request from the macro cell eNB, a first centimeter wave (cmW) frequency may be used, for receiving the APRS, a second cmW frequency may be used, and for receiving the BRS, a millimeter wave (mmW) frequency may be used.

In Example 21, an apparatus for an evolved Node B (eNB) may include a transceiver circuit and a hardware processing circuit. The hardware processing circuit may configure the transceiver circuit to send a small cell measurement request to a user equipment (UE) indicating one or more small cell access points (APs) for which the UE is to determine small cell signal quality measurements. The hardware processing circuit may further configure the transceiver circuit to receive the small cell signal quality measurements from the UE. The hardware processing circuit may further configure the transceiver circuit to send a pen cell measurement request to the UE indicating a set of candidate pen cells for which the UE is to determine pen cell signal quality measurements. At least a portion of the small cell APs may be arranged to support multiple pen cells for directed transmission of data messages to the UE.

In Example 22, the subject matter of Example 21, wherein the hardware processing circuitry may be configured to: determine the set of candidate pencil cells from pencil cells supported by the small cell AP. The determination may be based at least in part on received small cell signal quality measurements.

In Example 23, the subject matter of one or any combination of Examples 21-22, wherein the determination of the set of candidate pencil cells may be further based at least in part on a geographic layout of the pencil cells and a directional beam pattern of the pencil cells.

In Example 24, the subject matter of one or any combination of Examples 21-23, wherein the hardware processing circuitry further configures the transceiver circuitry to receive the pen cell signal quality measurement from the UE. The hardware processing circuitry may be configured to select a candidate pen cell for exchanging data messages with the UE. The selection may be based at least in part on the received pen cell signal quality measurement. The hardware processing circuitry may further configure the transceiver circuitry to send an indicator of the selected candidate pen cell to the UE.

In Example 25, the subject matter of one or any combination of Examples 21-24, wherein the measurement request may be sent in a macro cell channel resource at a first centimeter wave (cmW) frequency. The small cell signal quality measurement may be based on a signal sent by the small cell AP in the small cell channel resource at a second cmW frequency. The pen cell signal quality measurement may be based on a directional signal sent by the small cell AP in the pen cell channel resource at a millimeter wave (mmW) frequency.

In Example 26, the subject matter as described in one or any combination of Examples 21-25, wherein the eNB may be configured to operate as a macrocell eNB having a coverage area that may be larger than a combined coverage area including a coverage area of the small cell AP.

In Example 27, the subject matter of one or any combination of Examples 21-26, wherein the apparatus may further comprise: one or more antennas coupled to the transceiver circuitry for transmitting the measurement request and receiving the small cell signal quality measurement.

In Example 28, an apparatus for a small cell access point (AP) may include a transceiver circuit and a hardware processing circuit. The hardware processing circuit may configure the transceiver circuit to send an access point reference signal (APRS) in an APRS channel resource at a centimeter wave (cmW) frequency. The hardware processing circuit may further configure the transceiver circuit to send multiple beam reference signals (BRS) in a BRS channel resource at a millimeter wave (mmW) frequency, wherein the BRS is assigned to multiple directional pen cells supported by the small cell AP. The hardware processing circuit may further configure the transceiver circuit to receive an indication that one of the pen cells is selected by the small cell AP for sending a data message to a user equipment (UE). The hardware processing circuit may further configure the transceiver circuit to send a data message to the UE in the BRS channel resource according to the transmission direction assigned to the selected pen cell.

In Example 29, the subject matter of Example 28, wherein the data message may include a data portion and may also include a control portion based on a corresponding BRS assigned to the selected pen cell.

In Example 30, the subject matter of one or any combination of Examples 28-29, wherein the beamwidth of the APRS may be greater than the beamwidth of the BRS.

In Example 31, the subject matter of one or any combination of Examples 28-30, wherein the beamwidth of the APRS can be at least 90 degrees and the beamwidth of the BRS can be at most 15 degrees.

In Example 32, the subject matter as recited in one or any combination of Examples 28-31, wherein the coverage area of the APRS may be larger than a combined coverage area including the coverage area of the BRS.

In Example 33, the subject matter of one or any combination of Examples 28-32, wherein the apparatus may further comprise: one or more antennas coupled to the transceiver circuitry for transmitting the APRS, the BRS, and the data message.

The Abstract is provided to comply with 37 C.F.R. Section 1.72(b), which requires an abstract that will allow the reader to ascertain the nature and gist of the technical disclosure. It should be understood that it will not be used to limit or interpret the scope or meaning of the claims. The appended claims are hereby incorporated into the Detailed Description, where each claim stands on its own as a separate embodiment.

Claims (31)

1. An apparatus for a user equipment (UE), the apparatus comprising a transceiver circuit and a hardware processing circuit, the hardware processing circuit being configured to: Receive one or more Access Point Reference Signals (APRS) from one or more small cell access points (APs); Based on the reception of the APRS, one or more AP signal quality measurements are sent to the macro cell base station; The UE receives a pencil cell control message from the macro cell base station, the pencil cell control message indicating that the UE will determine one or more candidate pencil cells for signal quality measurement, the candidate pencil cells being supported by the small cell AP; Receive beam reference signal (BRS) for the candidate pencil-shaped cell from the small cell AP; and For pen-shaped cells not included in the pen-shaped cell control message, suppress the reception of BRS from the small cell AP. 2. The apparatus of claim 1, wherein the beamwidth of the APRS is greater than the beamwidth of the BRS. 3. The apparatus of claim 2, wherein the beamwidth of the APRS is at least 90 degrees and the beamwidth of the BRS is at most 15 degrees. 4. The apparatus of claim 1, wherein, for at least one of the small cell APs, the coverage area of the APRS for the small cell AP is greater than the combined coverage area including the coverage area of the BRS of the plurality of pen cells supported by the small cell AP. 5. The apparatus of claim 1, wherein: At the first centimeter wave (cmW) frequency, the pencil-shaped cell control message is received in the macro cell channel resources. At the second cmW frequency, the APRS is received in the small cell channel resources, and The BRS is received in the pencil cell channel resources at the millimeter wave (mmW) frequency. 6. The apparatus of claim 1, wherein the coverage area of the macro cell base station is larger than the combined coverage area including the coverage area of the small cell AP. 7. The apparatus of claim 1, wherein at least some of the candidate pen-shaped cells are supported by different small cell APs. 8. The apparatus of claim 1, wherein at least some of the candidate pen-shaped cells are supported by the same small cell AP. 9. The apparatus of claim 1, wherein at least one of the small cell APs supports the assigned BRS as a plurality of different candidate pen-shaped cells. 10. The apparatus of claim 1, wherein the hardware processing circuitry is configured to further configure the transceiver circuitry as follows: Based on the reception of the BRS, the pen-shaped cell signal quality measurement is sent to the macro cell base station; The macro cell base station receives a pen-shaped cell configuration message, the pen-shaped cell configuration message indicating one of the candidate pen-shaped cells selected by the macro cell base station for exchanging data messages with the UE; and Based on the selected candidate pen-shaped cell, data messages are received from the corresponding small cell AP that supports the selected candidate pen-shaped cell. 11. The apparatus of claim 10, wherein the hardware processing circuitry is configured to: The updated pen-shaped cell signal quality measurement for the candidate pen-shaped cell is sent to the macro cell base station; The UE receives a pen-shaped cell reconfiguration message from the macro cell base station, the pen-shaped cell reconfiguration message indicating the reconfiguration of the UE from a selected candidate pen-shaped cell to a candidate pen-shaped cell reconfigured for exchanging data messages with the UE; and Based on the reconfigured candidate pen-shaped cells, data messages are received from the corresponding small cell APs that support the reconfigured candidate pen-shaped cells. 12. The apparatus of claim 1, wherein the hardware processing circuitry is configured to further configure the transceiver circuitry as follows: The UE receives a small cell AP control message from the macro cell base station, the small cell AP control message indicating that the UE will receive the small cell AP of the APRS from it. 13. The apparatus of claim 1, wherein the pen-shaped cell control message further indicates the BRS assigned to the candidate pen-shaped cell. 14. The apparatus of claim 1, wherein the UE is configured to operate in accordance with the 3GPP Long Term Evolution (LTE) protocol to exchange messages with a macro base station. 15. The apparatus of claim 1, wherein the apparatus further comprises: one or more antennas coupled to the transceiver circuitry for receiving the pencil cell control message and transmitting the AP signal quality measurement. 16. A non-transitory computer-readable storage medium storing instructions that are executed by one or more processors to perform operations for a user equipment (UE) to communicate, the operations configuring the one or more processors to: Receive a request from the macro cell base station to determine small cell signal quality measurements based on access point reference signals (APRS) received at the UE from one or more small cell access points (APs). The small cell signal quality measurement determined by the UE is sent to the macro cell base station; and The macro cell base station receives a request to determine the pen-shaped cell signal quality measurement of a group of candidate pen-shaped cells supported by at least a portion of the small cell APs; Based on the pencil-shaped cells included in the candidate pencil-shaped cells, the directional beam reference signal (BRS) is received from the small cell AP, and Based on the pen-shaped cells not included in the candidate pen-shaped cells, suppress BRS reception from the small cell AP. The pen-shaped cell signal quality measurement is based on the BRS received at the UE from the small cell AP according to the candidate pen-shaped cell. 17. The non-transitory computer-readable storage medium of claim 16, wherein the operation is configured to further configure the one or more processors to: The signal quality measurement of the pencil cell determined by the UE is sent to the macro cell base station; Receive from the macro cell base station an indicator of the candidate pen-shaped cell selected by the base station for exchanging data messages with the UE; and Based on the selected candidate pen-shaped cell, data messages are received from the corresponding small cell AP that supports the selected candidate pen-shaped cell. 18. The non-transitory computer-readable storage medium of claim 16, wherein: For receiving the request from the macrocell base station, the first centimeter wave (cmW) frequency is used. For receiving the APRS, the second cmW frequency is used, and For receiving the BRS, millimeter wave (mmW) frequency is used. 19. An apparatus for a base station, the apparatus comprising transceiver circuitry and hardware processing circuitry, the hardware processing circuitry being configured to: The system will instruct the user equipment (UE) to send a small cell measurement request to one or more small cell access points (APs) for which it is to determine small cell signal quality measurements. Receive small cell signal quality measurements from the UE; and The system will instruct the UE to send a pencil cell measurement request to a set of candidate pencil cells for which it wants to determine pencil cell signal quality measurements, wherein the UE will suppress the determination of signal quality measurements for other pencil cells not included in the pencil cell measurement request. Among them, at least some of the small cell APs are configured to support multiple pen-shaped cells for directing data messages to the UE. 20. The apparatus of claim 19, wherein the hardware processing circuitry is configured to: The candidate pen-shaped cells are determined from the pen-shaped cells supported by the small cell AP, and the determination is based at least in part on the received small cell signal quality measurements. 21. The apparatus of claim 20, wherein determining the set of candidate pencil cells is further based at least in part on the geographical layout of the pencil cells and the directional beam pattern of the pencil cells. 22. The apparatus of claim 19, wherein the hardware processing circuitry is further configured to: The transceiver circuit is configured to receive the pencil cell signal quality measurement from the UE; Candidate pen-shaped cells are selected for exchanging data messages with the UE, the selection being based at least in part on received pen-shaped cell signal quality measurements; and The transceiver circuit is configured to send an indicator of the selected candidate pen-shaped cell to the UE. 23. The apparatus of claim 19, wherein: The measurement request is transmitted in the macrocell channel resources at the first centimeter wave (cmW) frequency. The small cell signal quality measurement is based on the signal transmitted by the small cell AP in the small cell channel resources at the second cmW frequency, and The pencil cell signal quality measurement is based on the directional signal transmitted by the small cell AP in the pencil cell channel resources at millimeter wave mmW frequency. 24. The apparatus of claim 19, wherein the base station is configured to operate as a macrocell base station with a coverage area greater than a combined coverage area including the coverage area of the small cell AP. 25. The apparatus of claim 19, wherein the apparatus further comprises: one or more antennas coupled to the transceiver circuitry for transmitting the measurement request and receiving the small cell signal quality measurement. 26. An apparatus for a small cell access point (AP), the apparatus comprising a transceiver circuit and a hardware processing circuit, the hardware processing circuit being configured to: At the centimeter wave (cmW) frequency, APRS is transmitted in the Access Point Reference Signal (APRS) channel resources; At the millimeter wave (mmW) frequency, multiple BRSs are transmitted in the beam reference signal (BRS) channel resources, wherein the BRSs are assigned to multiple directional pencil cells supported by the small cell AP. Receive an indication that one of the pen-shaped cells has been selected by the small cell AP for transmitting data messages to the user equipment (UE); and According to the transmission direction assigned to the selected pen-shaped cell, the data message is sent to the UE in the BRS channel resource, wherein for pen-shaped cells not included in the indication, the UE will suppress receiving BRS from the small cell AP. 27. The apparatus of claim 26, wherein the data message includes a data portion and further includes a control portion based on the corresponding BRS assigned to the selected pen-shaped cell. 28. The apparatus of claim 26, wherein the beamwidth of the APRS is greater than the beamwidth of the BRS. 29. The apparatus of claim 28, wherein the beamwidth of the APRS is at least 90 degrees and the beamwidth of the BRS is at most 15 degrees. 30. The apparatus of claim 26, wherein the coverage area of the APRS is larger than the combined coverage area including the coverage area of the BRS. 31. The apparatus of claim 26, wherein the apparatus further comprises: one or more antennas coupled to the transceiver circuitry for transmitting the APRS, the BRS, and the data messages.