Patent Description:
Embodiments pertain to systems, methods, and component devices associated with a millimeter wave capable small cell (MCSC) devices. In particular, systems and methods are described for user equipment (UE) association with a MCSC operating as a booster for a universal mobile telecommunications system terrestrial radio access node B (eNB).

Small cells are low-powered radio access nodes that may operate as part of a wireless communication network, with an small cell operational range that may be on the order of <NUM> to <NUM>. Small cells may be compared with macrocells which may have a range greater than <NUM>. of <NUM>-<NUM>. MCSC are small cells that use millimeter electromagnetic waves, including waves with a frequency between <NUM> gigahertz and <NUM> gigahertz, for communication.

<CIT> discloses a communication meth-od of a coordinator including: receiving a relay search request frame for requesting a search for at least one relay station between a destination station and a source station; and transmitting, in response to the relay search request frame, a relay search response frame including a list of the at least one relay station so that the source station selects a target relay station from the at least one relay station.

<CIT> discloses selective relaying for wireless networks wherein a relay may partially decode a frame to get enough information to know when to amplify and transmit the frame to a user.

<CIT> discloses (see <FIG> and <FIG>) a user equipment adapted to communicate with a base station, whereby both the user equipment and the base station are provided with sector antennas for transmission and reception.

The present invention is defined by the features of the independent claims. Preferred advantageous embodiments thereof are defined by the sub-features of the dependent claims.

Embodiments relate to systems, methods, and computer readable media to enable a millimeter wave capable small cell (MCSC) devices or other small cell devices to receive a handover of a user equipment from a universal mobile telecommunications system terrestrial radio access node B(eNB. ) In particular, systems and methods are described for user equipment (UE) association with a MCSC operating as a booster for an eNB, including identification of and communication on preferred cell sector between the UE and the MCSC. The following description and the drawings illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments can incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments can be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims.

In various implementations, a MCSC can work as a booster cell in an anchor-booster architecture, where the MCSC operating as a booster cell for an eNB offloads a portion of the traffic for a UE being managed by the eNB. MCSC operation as a booster cell supports highly efficient delivery of user traffic within the MCSC cell area that is a subset of the area covered by the eNB, and may enable signal quality assurance for UE during periods of high communication rates or in congested areas of eNB coverage. Such booster operation may provide particular benefits when a booster MCSC may be deployed in a different frequency band than the eNB frequency band due to relaxed interference between communication layers. An MCSC acting as a booster operating at millimeter wave frequencies may thus be a modular improvement to certain eNB systems if the UE operating within the eNB coverage area support millimeter wave frequencies. Alternatively, an MCSC can act as a secondary carrier where a backhaul communication link is directly available to the MCSC rather than as a booster. In both such implementations, the MCSC will be part of handover processes to manage UE communications as the UE moves.

Embodiments described herein related to signal quality measurements on a sector basis, association between a UE and an MCSC as part of a handover from an eNB, and coarse beamforming training. Additionally, embodiments further include a high level design of PSS/SSS and PRACH sequences which are customized for the handover of the UE between the eNB and the MCSC.

<FIG> illustrates a wireless network <NUM> in accordance with some embodiments. The wireless network <NUM> includes user equipment (UE) <NUM>, <NUM> and <NUM>. The UEs <NUM>, <NUM>, and <NUM> may be, for example, laptop computers, smart phones, tablet computers, printers, machine-type devices such as smart meters, or any other wireless device with or without a user interface. In an example, the UEs <NUM>, <NUM> and <NUM> have a wireless connection through a millimeter wave capable small cell <NUM>, through universal mobile telecommunications system terrestrial radio access node B (eNB), or through both to the wireless network <NUM>. The wireless network <NUM> may represent an interconnection of a number of networks. For instance, the wireless network <NUM> may couple with a wide area network such as the Internet or an intranet.

MCSC <NUM> provides communication support in a service area <NUM>. Service area <NUM> is at least partially within an eNB service area provided by eNB <NUM>. Service area <NUM> and the eNB service area associated with eNB <NUM> are each supported by antennas integrated with MCSC <NUM> and eNB <NUM> for their respective service areas. The service areas will be divided into a number of sectors associated with certain antennas. Such sectors may be physically associated with fixed antennas, or may be assigned to a physical area with tunable antennas or antenna settings adjustable in a beamforming process used to direct a signal to a particular sector. One embodiment of eNB <NUM>, for example, includes three sectors each covering a <NUM> degree area with an array of antennas directed to each sector to provide <NUM> degree coverage around eNB <NUM>.

MCSC <NUM>, using millimeter wave signals may use antenna that are highly directional, and may thus use several different antennas which each cover a small directional arc from the location of the MCSC. The signals directed into such arcs may overlap to provide an acceptable quality level over a service area. While service area <NUM> is shown as a circle, in certain embodiments, MCSC <NUM> may be structured so that the sectors in service area <NUM> may not cover an area <NUM> degrees around the location of MCSC <NUM>. MCSC <NUM> may thus be configured to support directional wireless links with multiple UE devices using millimeter wave communications. In certain embodiments, MCSC <NUM> may transmit to a UE such as UE <NUM> using a millimeter wave channel, and may receive communications back from UE <NUM> on a different channel. The return channel may be the same millimeter wave channel a different millimeter wave channel, or may be an omnidirectional communication or other communication not using a millimeter wave channel. In certain embodiments, physical blocking structures may create gaps in service area <NUM> or the eNB service area, and multiple MCSC may be placed in different positions such that the eNB service area, service area <NUM>, and service areas associated with other MCSC will provide consistent signal coverage over a given area. In certain environments, such as multi-level buildings, this may include coverage at certain elevations in addition to ground level coverage which is represented two dimensionally by service area <NUM>.

In certain environments, eNB <NUM> and MCSC <NUM> may additionally operate with other signal sources such as a wireless access point (AP) or a personal basic service set (PBSS) control point (PCP) which may further be used to provide consistent signal coverage.

<FIG> shows one example embodiment of a method for cell association and beamforming training with a MCSC, shown as method <NUM>. While method <NUM> may be implemented with a variety of different systems, for illustrative purposes, method <NUM> is described below with respect to network <NUM> of <FIG>. Additionally, while method <NUM> describes one example embodiment, it will be apparent that other embodiments are possible within the scope of the innovations described herein.

In operation <NUM>, UE <NUM> transmits UE synchronization signals in a first plurality of sectors. Such sectors may be defined by antennas of UE <NUM> or any system or transmission configurations of UE <NUM>. An example of UE synchronization signals sent in a plurality of sectors is shown by random access codes <NUM> of <FIG>, with each random access code 434a through 434n sent in a different sector.

In operation <NUM>, UE <NUM> receives, from MCSC <NUM>, MCSC synchronization signals in a second plurality of sectors. As described above, such sectors may be defined by antennas of MCSC <NUM> or any system or transmission configuration of MCSC <NUM>. An example of MCSC synchronization signals sent in a plurality of sectors is shown by MCSC synchronization signals <NUM> of <FIG>, with each MCSC synchronization signal 404a through 404n sent in a different sector.

In operation <NUM>, UE <NUM> measures in response to a measurement request, a signal quality for at least a first sector of the second plurality of sectors. Such a measurement request may be received at UE <NUM> from eNB <NUM>, or from any other authorized source.

In operation <NUM>, UE <NUM> analyzes the signal quality for at least the first sector to select the first sector based on a first signal quality of the first sector. In operation <NUM>, UE 115communicate, from the UE <NUM> eNB <NUM>, a cell identifier and a first sector identifier associated with the first sector.

Additional embodiments may further operate where UE <NUM> receives, from the eNB, the measurement request prior to receipt of the MCSC synchronization signals in the second plurality of sectors, and where UE <NUM> determines, from the MCSC synchronization signals, a cell identifier associated with the MCSC <NUM> and a sector identifier associated with each sector of the second plurality of sectors.

Additional embodiments may further operate where each MCSC synchronization signal per sector of the second plurality of sectors comprises a primary synchronization signal (PSS) comprising two continuous symbols and a secondary synchronization signal (SSS) that follows the PSS.

Additional embodiments may further operate where the signal quality for each sector of the second plurality of sectors is based, at least in part, on at least one of a received signal strength indication (RSSI), a reference signal received power (RSRP), and a reference signal received quality (RSRQ) value of the first synchronization signal for each sector of the plurality of sectors.

Additional embodiments may further operate where UE <NUM> receives, from the eNB <NUM>, a radio resource control (RRC) connection reconfiguration communication in response to communication of the cell identifier to the eNB.

Additional embodiments may further operate where the RRC connection reconfiguration communication comprises mobility control information and where the RRC connection reconfiguration communication is received in response to a handover communication between the eNB <NUM> and the MCSC <NUM>.

Additional embodiments may further operate where analyzing the signal quality for at least the first sector of the plurality of sectors to select the first sector comprises determining a quality value for each sector of the plurality of sectors as a function the RSSI, the RSRP, and the RSRQ, determining a best quality value from the quality value for each sector of the plurality of sectors, and selecting a sector associated with the best quality value as the first sector.

Additional embodiments may further operate where the RRC connection reconfiguration is further received in response to a handover decision made by the eNB based on the first signal quality of the first sector.

Additional embodiments may further operate where UE <NUM> receives, from the eNB <NUM>, the cell identifier, a master information block (MIB), and a set of physical random access channel (PRACH) codes via a physical shared downlink channel (PDSCH).

Additional embodiments may further operate where UE <NUM> periodically receives a retransmission of the synchronization signal from the MCSC <NUM> and performs a timing acquisition using the PSS.

Additional embodiments may further operate where UE <NUM> performs a reverse direction training at least in part by communicating, from the UE to the eNB, a PRACH code of the set of PRACH codes to each of the first plurality of sectors as part of transmission of the UE synchronization signal in the first plurality of sectors.

Additional embodiments may further operate where the set of PRACH codes comprises number of PRACH codes equal to a random access code base number times a number of sectors.

Additional embodiments may further operate where each PRACH code of the set of PRACH codes comprises a base PRACH code and sector identification information.

Additional embodiments may further operate where UE <NUM> receives at the UE, in response to the reverse direction training, a cell radio network temporary identifier (C-RNTI) and a timing advance (TA) command.

Another embodiment may be a method performed by UE <NUM> operating with an eNB <NUM> and MCSC <NUM>. Such a method may involve receiving, at the UE <NUM> from the eNB <NUM>, a measurement request, and receiving, at the UE <NUM> from the MCSC <NUM>, an MCSC synchronization signal in each sector of a first plurality of sectors. Such a method may also involve determining, by the UE <NUM>, a cell identifier associated with the MCSC <NUM> and a sector identifier associated with each sector, selecting a sector in response to the measurement request, and communicating, from the UE <NUM> to the eNB <NUM>, the cell identifier and a first sector identifier associated with the selected sector.

Additional such embodiments may further operate where selecting the sector in response to the measurement request comprises measuring, at the UE <NUM> in response to the measurement request, a signal quality for each sector of the first plurality of sectors, and analyzing the signal quality for each sector of the first plurality of sectors to select a first sector based on a first signal quality of the first sector.

Additional such embodiments may further operate where the signal quality for each sector is a function of a received signal strength indication (RSSI), a reference signal received power (RSRP), and a reference signal received quality (RSRQ) value of the first synchronization signal for each sector of the first plurality of sectors.

Additional such embodiments may further involve receiving, at the UE from the eNB, a radio resource control (RRC) connection reconfiguration communication in response to communication of the cell identifier to the eNB, receiving, at the UE from the eNB, the cell identifier, a master information block (MIB), and a set of physical random access channel (PRACH) codes via a physical shared downlink channel (PDSCH), and performing a reverse direction training at least in part by communicating, from the UE to the eNB, a PRACH code of the set of PRACH codes for each sector of the first plurality of sectors. Such an embodiment may operate where the PRACH code comprises a base PRACH code, sector information for reverse direction training, and eNB sector information for beamforming training acknowledgement.

Additional such embodiments may further operate where the MCSC synchronization signal is received as part of a millimeter wave communication from the MCSC with a communication frequency between <NUM> and <NUM>. In other embodiments, any millimeter wave frequency may be used. In still further embodiments, both millimeter wave frequencies and non-millimeter wave frequencies may be used.

Additional embodiments, as detailed further below, may comprise non-transitory computer readable medium. In such an embodiment, the medium comprises instructions that, when executed by a processor, cause UE <NUM> to take certain actions. In one such example embodiment, the instructions cause the UE <NUM> receive, from eNB <NUM>, a measurement request and receive, from MCSC <NUM> a MCSC synchronization signal in a second plurality of sectors. The instructions may further cause UE <NUM> to determine, a cell identifier associated with the MCSC <NUM> and a sector identifier associated with each sector of the second plurality of sectors. The instructions may still further cause UE <NUM> to measure, at the UE in response to the measurement request, a signal quality for each sector of the second plurality of sectors, to analyze the signal quality for each sector of the second plurality of sectors to select a first sector of the plurality of sectors based on a first signal quality of the first sector, and to communicate, from the UE to an evolved universal terrestrial radio access node B (eNB), a cell identifier and a first sector identifier associated with the first sector.

In further embodiments, the instructions may further cause the UE <NUM> to transmit a UE synchronization signal in a first plurality of sectors; receive, from the eNB <NUM>, a radio resource control (RRC) connection reconfiguration communication in response to communication of the cell identifier to the eNB; and receive, from the eNB, the cell identifier, a master information block (MIB), and a set of physical random access channel (PRACH) codes via a physical shared downlink channel (PDSCH).

In still further embodiments, the instructions may further cause the UE <NUM> to periodically receive a retransmission of the MCSC synchronization signal from the MCSC <NUM>, perform, by the UE <NUM>, a timing acquisition using a primary synchronization signal (PSS) of the MCSC synchronization signal; perform a reverse direction training at least in part by communicating, from the UE <NUM> to the eNB <NUM>, a PRACH code of the set of the PRACH codes as part of transmission of the UE synchronization signal in each sector of the first plurality of sectors; and receive, in response to the reverse direction training, a cell radio network temporary identifier (C-RNTI) and a timing advance (TA) command.

<FIG> shows a flowchart of method <NUM> describing another embodiment of cell association and beamforming training with an MCSC. Just as above for method <NUM>, while the operations of method <NUM> may be performed using various different systems, method <NUM> is particularly described using the elements of network <NUM> from <FIG>. Method <NUM> shows a series of operations and communications between UE <NUM>, MCSC <NUM>, and eNB <NUM>, with the operations proceeding from top to bottom. In alternative embodiments, any operation described herein may be performed simultaneously with similar operations being performed with other elements, such that MCSC <NUM> may communicate with other UE such as UE <NUM> or UE <NUM>. ENB <NUM> may similarly communicate with MCSC <NUM> and with another different MCSC at the same time, such that a system may perform aspects of the operations described by method <NUM> at the same time.

Additionally, the embodiment below describes MCSC <NUM> operating as a booster cell, with the use of handover commands sent to MCSC <NUM> by eNB <NUM>. In an alternate embodiment with an MCSC such as MCSC <NUM> working as a secondary carrier instead of a booster cell, the MCSC <NUM> of network <NUM> would include a direct connection to wireless network <NUM>, similar to the connection shown between eNB <NUM> and wireless network <NUM>. In such an embodiment with the MCSC <NUM> working as a secondary carrier, eNB <NUM> may use activation/de-activation procedures instead of handover procedures to enable a UE such as UE <NUM> to use MCSC <NUM> for wireless traffic.

Method <NUM> begins with an operation for radio resource control (RCC) reconfiguration <NUM>, which functions as a measurement request made by eNB <NUM> and communicated to UE <NUM>. In certain embodiments, this may be similar to a standard Long-Term Evolution (LTE) RCC reconfiguration using a "measConfig" operation.

Sector sweep <NUM> may be part a repeated operation that occurs continuously or periodically as part of a system setting. In one example, sector sweep <NUM> may be part of an operation that repeats every <NUM> milliseconds. In other embodiments, any other such periodic or system selected repetition may be used. Sector sweep <NUM> involves communication of MCSC synchronization signals from MCSC <NUM> that are received by UE <NUM>. The synchronization signals may be sent in multiple sectors repeatedly.

<FIG> describes aspects of one embodiment of MCSC synchronization signals <NUM> that are communicated to a plurality of sectors. Synchronization signals <NUM> includes a signal communicated to a first sector as synchronization signal 404a, to a second sector as synchronization signal 404b, to an Nth sector as synchronization signal 404n, and so on. Such signals may be received by UE <NUM>, as well as by any other UE within a signal area covered by a synchronization signal sent to a particular sector. In certain embodiments, certain synchronization signals of synchronization signals <NUM> may not be received by UE <NUM> while at least one signal of synchronization signals <NUM> is received by UE <NUM>.

In one embodiment comprising a frame structure, multiple continuous symbols may be used as part of the MCSC synchronization signals <NUM>, with a primary synchronization signal (PSS) and a secondary synchronization signal (SSS. ) Such a system may operate using a PSS code space that is expanded from a standard three sector LTE code space to a multiple sector design. For example, and expanded PSS code space may include space for <NUM> sectors or <NUM> sectors. To enable efficient detection of the PSS, the PSS sequence within an individual synchronization signal of MCSC synchronization signals <NUM> may have an internally repetitive pattern.

For example, one embodiment of a PSS sequence may be placed at every odd tone or every even tone in a frequency domain, resulting in a time domain repetition and allowing auto-correlation for timing acquisition and frame boundary detection. Cross-correlation may then be applied by a detector to detect the sector identifier. The SSS, which includes the cell identifier, may follow a similar design with coherent detection enabled by the design of the SSS. The detailed sequence of PSS and SSS elements of a synchronization signal may be set based on the bandwidth of the MCSC system and the sampling rate and symbol duration of a system in which the MCSC <NUM> operates. Such a detailed sequence may also be set based on the number of sectors used by MCSC <NUM>.

<FIG> illustrates one embodiment of a MCSC synchronization signal 504a. In certain implementations of MCSC synchronization signals <NUM>, MCSC synchronization signal 404a may be similar to MCSC synchronization signal 504a. MCSC synchronization signal 504a includes two PSS communications shown as first PSS 504a1 and second PSS 504a2. Second PSS 504a2 is followed by a single SSS 504a3. MCSC synchronization signal 504a may then be followed by a other MCSC synchronization signals as part of a sector sweep using MCSC synchronization signals with each MCSC synchronization signal having the two PSS/one SSS synchronization signal structure.

The operation for signal quality analysis <NUM> then includes reception of one or more MCSC synchronization signals <NUM> such as MCSC synchronization signal 404a, and performance of a signal quality analysis by UE <NUM> on each received MCSC synchronization signal. The signal quality may be based, at least in part, on a received signal strength indication (RSSI), a reference signal received power (RSRP), a reference signal received quality (RSRQ) value of the first synchronization signal for each sector of the plurality of sectors, or any combination of these or other values determined from the received MCSC synchronization signals <NUM>. UE <NUM> then selects a sector based on the quality analysis. In one embodiment, for example, UE <NUM> may determine a quality value for each sector of the plurality of sectors as a function the RSSI, the RSRP, and the RSRQ, determine a best quality value from the quality value for each sector of the plurality of sectors, and select a sector associated with the best quality value as the first sector. This may, for example, be a largest or smallest quality value selected from the quality value for each sector.

Measurement report <NUM> then is an operation where UE <NUM> communicates the results of the quality analysis performed as part of signal quality analysis <NUM>. Measurement report <NUM> may include quality numbers for each sector by, for example, sending an RSSI value, an RSRP value, and an RSRQ value for each sector. Measurement report <NUM> may alternatively send such values or another value such as a calculated quality value that is a function of such quality numbers.

ENB <NUM> may then receive the information from measurement report <NUM> and use this information to make a handover decision. This handover decision may be based on quality analysis thresholds, based on a comparison with similar quality analysis numbers associated with signals from eNB <NUM> to UE <NUM>, or based on any other such handover decision thresholds. Such handover decisions may be based on existing LTE handover standards between eNBs, or may be based on handover processes customized for MCSC operations. Additionally the handover decisions may be different depending on whether MCSC <NUM> is operating as a booster for eNB <NUM>, or whether MCSC <NUM> is operating as an independent cell.

When eNB <NUM> determines that UE <NUM> will be passed to MCSC <NUM> from eNB <NUM>, eNB performs a handover hand shake with MCSC <NUM>. This handover process as shown by method <NUM> includes a handover request <NUM> including a communication from eNB <NUM> to MCSC <NUM>, a handover response <NUM> communication from MCSC <NUM>, and an RRC reconfiguration <NUM> communication from eNB <NUM> to UE <NUM>.

After this initial portion of the handover, target small cell <NUM> operation involves a communication of applicable handover information from eNB <NUM> to UE <NUM>. This handover information includes a master information block (MIB), and a physical random access channel (PRACH) code via a physical shared downlink channel (PDSCH) or any available communication link. The handover information may also include system information blocks (SIB), the sector identified by signal quality analysis <NUM>, and any other such handover information.

Sector sweep <NUM> is then a continuation of the transmission of MCSC synchronization signals <NUM> sent by MCSC <NUM>. These additional repetitions of MCSC synchronization signals <NUM> may then be received by UE <NUM>. Refine training <NUM> is then an operation performed by UE <NUM> to use the portion of the MCSC synchronization signals <NUM> received by UE <NUM> from sector sweep <NUM> to perform timing acquisition. The timing acquisition performed by UE <NUM> may use PSS portions of individual MCSC synchronization signals such as MCSC synchronization signal 404b along with the handover information received as part of target small cell <NUM>. Refine training <NUM> may additional involve a repeat of the quality analysis of signal quality analysis <NUM> to determine if a new sector is associated with the best signal quality. In certain embodiments, if a UE is not moving and an elapsed time between sector sweep <NUM> and sector sweep <NUM> is small, UE <NUM> may determine that refine training <NUM> is not needed and refine training <NUM> may not be performed. This determination may be based on threshold setting stored in UE <NUM> and associated with the UE <NUM> movement and an elapsed time between receipt of MCSC synchronization signals in sector sweep <NUM> and sector sweep <NUM>.

The operation for sector sweep PRACH <NUM> is then part of a reverse training from UE <NUM> to MCSC <NUM>. As part of this reverse training, UE <NUM> sends the access codes received as part of handover information from the target small cell <NUM> operation. This includes an access code for each sector as shown by <FIG>, such that UE <NUM> sends a sector <NUM> random access code 434a, a sector two random access code 434b, a sector n random access code 434n, and so on. In various embodiments, this may be a PRACH code which may be modified from a standardized base of <NUM> random access codes in a variety of ways, as illustrated by <FIG>. <FIG> thus shows UE synchronization signals sent by UE <NUM> in a first plurality of sectors, where <FIG> shows MCSC synchronization signals sent in a separate second plurality of sectors.

<FIG> illustrates an example of an access code that may be used as part of sector sweep PRACH <NUM> as random access code <NUM>. Random access code <NUM> one access code from a set of expanded PRACH codes, with the set comprising a number of codes equal to <NUM> codes times the number of sectors used by MCSC <NUM>. For example, if MCSC <NUM> used <NUM> sectors, the set of expanded PRACH codes which random access code <NUM> is part of would include <NUM> different access codes. If MCSC <NUM> used <NUM> sectors, the set of expanded PRACH codes which random access code <NUM> is part of would include <NUM> different access codes.

<FIG> additional examples of access codes that may be used as part of sector sweep PRACH <NUM>. Random access code <NUM> includes a standard PRACH code followed by sector information. The set of PRACH codes of which random access code <NUM> is a part would include the same number of different random access codes as the set of PRACH codes that random access code <NUM> is part of, but would simply include the sector information as part of the code rather than <NUM> unique random codes for each sector. Random access code <NUM> is an example of sector information that may be included in a random access code when refine training <NUM> determines that a UE <NUM> has moved an a new best sector different from the best sector determined with signal quality analysis <NUM> is associated with the new UE position. Random access code <NUM> thus includes a sector instead of merely including sector identification information. Random access code <NUM> thus includes not only a PRACH code, but also reverse direction training information and beamforming training acknowledgment information.

After the UE <NUM> sector sweep PRACH <NUM> operation completes communication of random access codes <NUM> as illustrated by <FIG>, MCSC <NUM> sends a random access response including a cell radio network temporary identifier (C-RNTI) and a timing advance (TA) command as part of PRACH response <NUM>. Additionally, MCSC <NUM> may analyze the random access codes <NUM> that were received by MCSC <NUM> from sector sweep PRACH <NUM>, and MCSC <NUM> may determine a best sector based on the random access codes <NUM> communicated in different sectors. This may use a signal quality analysis performed by MCSC <NUM> that is similar or identical any sector analysis described above for signal quality analysis <NUM>. This may also involve additional or alternative different analysis of the sectors used for random access codes <NUM>.

As discussed above, method <NUM> is particularly directed to an embodiment with MCSC <NUM> operating as a booster for eNB <NUM>. In an alternate embodiment with an MCSC such as MCSC <NUM> working as a secondary carrier instead of a booster cell, eNB <NUM> may use activation/deactivation procedures instead of handover procedures to enable a UE such as UE <NUM> to use MCSC <NUM> for wireless traffic. In such embodiments, handover request <NUM> and handover response <NUM> may be replaced or enhanced with activation and deactivation actions directed to MCSC <NUM>, with MCSC <NUM> responsive to such activation and deactivation commands from eNB.

<FIG> shows an example UE, illustrated as UE <NUM>. UE <NUM> may be an implementation of UE <NUM>, UE <NUM>, or any UE described herein, and may include circuitry configured to communicate with an MCSC such as MCSC <NUM> as well as circuitry to enable communication with an eNB such as eNB <NUM>.

The UE <NUM> can include one or more antennas configured to communicate with transmission station, such as a base station (BS), an evolved Node B (eNB), a RRU, or other type of wireless wide area network (WWAN) access point. The mobile device can be configured to communicate using at least one wireless communication standard including 3GPP LTE. WiMAX, High Speed Packet Access (HSPA), Bluetooth, and WiFi. The mobile device can communicate using separate antennas for each wireless communication standard or shared antennas for multiple wireless communication standards. The mobile device can communicate in a wireless local area network (WLAN), a wireless personal area network (WPAN), and/or a WWAN.

<FIG> illustrates an example of a UE <NUM>. The UE <NUM> can be any mobile device, a mobile station (MS), a mobile wireless device, a mobile communication device, a tablet, a handset, or other type of mobile wireless computing device. The UE <NUM> can include one or more antennas <NUM> within housing <NUM> that are configured to communicate with a hotspot, base station (BS), an eNB, or other type of WLAN or WWAN access point. UE may thus communicate with a WAN such as the Internet via an eNB or base station transceiver implemented as part of an asymmetric RAN as detailed above. UE <NUM> can be configured to communicate using multiple wireless communication standards, including standards selected from 3GPP LTE, WiMAX, High Speed Packet Access (HSPA), Bluetooth, and Wi-Fi standard definitions. The UE <NUM> can communicate using separate antennas for each wireless communication standard or shared antennas for multiple wireless communication standards. The UE <NUM> can communicate in a WLAN, a WPAN, and/or a WWAN.

<FIG> also shows a microphone <NUM> and one or more speakers <NUM> that can be used for audio input and output from the UE <NUM>. A display screen <NUM> can be a liquid crystal display (LCD) screen, or other type of display screen such as an organic light emitting diode (OLED) display. The display screen <NUM> can be configured as a touch screen. The touch screen can use capacitive, resistive, or another type of touch screen technology. An application processor <NUM> and a graphics processor <NUM> can be coupled to internal memory <NUM> to provide processing and display capabilities. A non-volatile memory port <NUM> can also be used to provide data input/output options to a user. The non-volatile memory port <NUM> can also be used to expand the memory capabilities of the UE <NUM>. A keyboard <NUM> can be integrated with the UE <NUM> or wirelessly connected to the UE <NUM> to provide additional user input. A virtual keyboard can also be provided using the touch screen. A camera <NUM> located on the front (display screen) side or the rear side of the UE <NUM> can also be integrated into the housing <NUM> of the UE <NUM>. Any such elements may be used to generate information that may be communicated as uplink data via an asymmetric C-RAN and to receive information that may be communicated as downlink data via an asymmetric C-RAN as described herein.

<FIG> is a block diagram illustrating an example computer system machine <NUM> upon which any one or more of the methodologies herein discussed can be run, including MCSC <NUM>, eNB <NUM>, and UE <NUM>. In various alternative embodiments, the machine operates as a standalone device or can be connected (e.g., networked) to other machines. In a networked deployment, the machine can operate in the capacity of either a server or a client machine in server-client network environments, or it can act as a peer machine in peer-to-peer (or distributed) network environments. The machine can be a personal computer (PC) that may or may not be portable (e.g., a notebook or a netbook), a tablet, a set-top box (STB), a gaming console, a Personal Digital Assistant (PDA), a mobile telephone or smartphone, a web appliance, a network router, switch or bridge, or any machine capable of executing instructions (sequential or otherwise) that specify actions to be taken by that machine. Further, while only a single machine is illustrated, the term "machine" shall also be taken to include any collection of machines that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein.

Example computer system machine <NUM> includes a processor <NUM> (e.g., a central processing unit (CPU), a graphics processing unit (GPU) or both), a main memory <NUM> and a static memory <NUM>, which communicate with each other via an interconnect <NUM> (e.g., a link, a bus, etc.). The computer system machine <NUM> can further include a video display unit <NUM>, an alphanumeric input device <NUM> (e.g., a keyboard), and a user interface (UI) navigation device <NUM> (e.g., a mouse). In one embodiment, the video display unit <NUM>, input device <NUM> and UI navigation device <NUM> are a touch screen display. The computer system machine <NUM> can additionally include a storage device <NUM> (e.g., a drive unit), a signal generation device <NUM> (e.g., a speaker), an output controller <NUM>, a power management controller <NUM>, and a network interface device <NUM> (which can include or operably communicate with one or more antennas <NUM>, transceivers, or other wireless communications hardware), and one or more sensors <NUM>, such as a Global Positioning Sensor (GPS) sensor, compass, location sensor, accelerometer, or other sensor.

The storage device <NUM> includes a machine-readable medium <NUM> on which is stored one or more sets of data structures and instructions <NUM> (e.g., software) embodying or utilized by any one or more of the methodologies or functions described herein. The instructions <NUM> can also reside, completely or at least partially, within the main memory <NUM>, static memory <NUM>, and/or within the processor <NUM> during execution thereof by the computer system machine <NUM>, with the main memory <NUM>, static memory <NUM>, and the processor <NUM> also constituting machine-readable media.

While the machine-readable medium <NUM> is illustrated in an example embodiment to be a single medium, the term "machine-readable medium" can include a single medium or multiple media (e.g., a centralized or distributed database, and/or associated caches and servers) that store the one or more instructions <NUM>. The term "machine-readable medium" shall also be taken to include any tangible medium that is capable of storing, encoding or carrying instructions for execution by the machine and that cause the machine to perform any one or more of the methodologies of the present disclosure or that is capable of storing, encoding or carrying data structures utilized by or associated with such instructions.

The instructions <NUM> can further be transmitted or received over a communications network <NUM> using a transmission medium via the network interface device <NUM> utilizing any one of a number of well-known transfer protocols (e.g., HTTP). The term "transmission medium" shall be taken to include any intangible medium that is capable of storing, encoding, or carrying instructions for execution by the machine, and includes digital or analog communications signals or other intangible medium to facilitate communication of such software.

Various techniques, or certain aspects or portions thereof may take the form of program code (i.e., instructions) embodied in tangible media, such as floppy diskettes, CD-ROMs, hard drives, non-transitory computer readable storage medium, or any other machine-readable storage medium wherein, when the program code is loaded into and executed by a machine, such as a computer, the machine becomes an apparatus for practicing the various techniques. In the case of program code execution on programmable computers, the computing device may include a processor, a storage medium readable by the processor (including volatile and non-volatile memory and/or storage elements), at least one input device, and at least one output device. The volatile and non-volatile memory and/or storage elements may be a RAM, EPROM, flash drive, optical drive, magnetic hard drive, or other medium for storing electronic data. The base station and mobile station may also include a transceiver module, a counter module, a processing module, and/or a clock module or timer module. One or more programs that may implement or utilize the various techniques described herein may use an application programming interface (API), reusable controls, and the like. Such programs may be implemented in a high level procedural or object oriented programming language to communicate with a computer system. However, the program(s) may be implemented in assembly or machine language, if desired. In any case, the language may be a compiled or interpreted language, and combined with hardware implementations.

Various embodiments may use 3GPP LTE/LTE-A, IEEE <NUM>, and Bluetooth communication standards. Various alternative embodiments may use a variety of other WWAN, WLAN, and WPAN protocols and standards can be used in connection with the techniques described herein. These standards include, but are not limited to, other standards from 3GPP (e.g., HSPA+, UMTS), IEEE <NUM> (e.g., <NUM>. 16p), or Bluetooth (e.g., Bluetooth <NUM>, or like standards defined by the Bluetooth Special Interest Group) standards families. Other applicable network configurations can be included within the scope of the presently described communication networks. It will be understood that communications on such communication networks can be facilitated using any number of personal area networks, LANs, and WANs, using any combination of wired or wireless transmission mediums.

The embodiments described above can be implemented in one or a combination of hardware, firmware, and software. Various methods or techniques, or certain aspects or portions thereof, can take the form of program code (i.e., instructions) embodied in tangible media, such as flash memory, hard drives, portable storage devices, read-only memory (ROM), random-access memory (RAM), semiconductor memory devices (e.g., Electrically Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM)), magnetic disk storage media, optical storage media, and any other machine-readable storage medium or storage device wherein, when the program code is loaded into and executed by a machine, such as a computer or networking device, the machine becomes an apparatus for practicing the various techniques.

A machine-readable storage medium or other storage device can include any non-transitory mechanism for storing information in a form readable by a machine (e.g., a computer). In the case of program code executing on programmable computers, the computing device can include a processor, a storage medium readable by the processor (including volatile and non-volatile memory and/or storage elements), at least one input device, and at least one output device. One or more programs that can implement or utilize the various techniques described herein can use an application programming interface (API), reusable controls, and the like. Such programs can be implemented in a high level procedural or object oriented programming language to communicate with a computer system. However, the program(s) can be implemented in assembly or machine language, if desired. In any case, the language can be a compiled or interpreted language, and combined with hardware implementations.

It should be understood that the functional units or capabilities described in this specification can have been referred to or labeled as components or modules, in order to more particularly emphasize their implementation independence. For example, a component or module can be implemented as a hardware circuit comprising custom very-large-scale integration (VLSI) circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components. A component or module can also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices, or the like. Components or modules can also be implemented in software for execution by various types of processors. An identified component or module of executable code can, for instance, comprise one or more physical or logical blocks of computer instructions, which can, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified component or module need not be physically located together, but can comprise disparate instructions stored in different locations which, when joined logically together, comprise the component or module and achieve the stated purpose for the component or module.

Indeed, a component or module of executable code can be a single instruction, or many instructions, and can even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data can be identified and illustrated herein within components or modules, and can be embodied in any suitable form and organized within any suitable type of data structure. The operational data can be collected as a single data set, or can be distributed over different locations including over different storage devices, and can exist, at least partially, merely as electronic signals on a system or network. The components or modules can be passive or active, including agents operable to perform desired functions.

Claim 1:
A user equipment, UE, adapted to communicate with a base station, BS, and a millimeter wave capable small cell, MCSC, the UE comprising circuitry configured to:
receive (<NUM>), from the MCSC, MCSC synchronization signals in a second plurality of cell sectors, wherein the second plurality of cell sectors is defined by antennas of the MCSC, wherein each of the MCSC synchronization signals is sent in a different cell sector of the second plurality of cell sectors;
measure, at the UE in response to a measurement request, a signal quality for at least a first cell sector of the second plurality of cell sectors;
analyze (<NUM>) the signal quality for at least the first cell sector of the second plurality of cell sectors to select the first cell sector of the second plurality of cell sectors based on a first signal quality of the first cell sector of the second plurality of cell sectors;
communicate (<NUM>), from the UE to a base station, a cell identifier and a first sector identifier associated with the first cell sector of the second plurality of cell sectors; and
perform reverse direction training, including transmitting (<NUM>), from the UE to the MCSC, random access codes in a first plurality of sectors, wherein each of the random access codes includes reverse direction training information and beamforming training acknowledgement information, wherein the first plurality of sectors is defined by antennas of the UE, wherein the second plurality of cell sectors and the first plurality of sectors belong to a service area provided by the base station, wherein each random access code of said random access codes is transmitted in a different sector of said first plurality of sectors.