Abstract: Methods, systems, and devices are described for hierarchical communications within a wireless communications system. An eNB and/or a UE may be configured to operate within the wireless communications system which is at least partially defined through a first layer with first layer transmissions having a first subframe type and a second layer with second layer transmissions having a second subframe type. The first subframe type may have a first round trip time (RTT) between transmission and acknowledgment of receipt of the transmission, and the second layer may have a second RTT that is less than the first RTT. Subframes of the first subframe type may be multiplexed with subframes of the second subframe type, such as through time division multiplexing.

Abstract: Methods, systems, and devices are described for hierarchical communications and low latency support within a wireless communications system. An eNB and/or a UE may be configured to operate within the wireless communications system which is at least partially defined through a first layer with first layer transmissions having a first subframe type and a second layer with second layer transmissions having a second subframe type. The first subframe type may have a first round trip time (RTT) between transmission and acknowledgment of receipt of the transmission, and the second layer may have a second RTT that is less than the first RTT. Subframes of the first subframe type may be multiplexed with subframes of the second subframe type, such as through time division multiplexing. In some examples symbols of different duration may be multiplexed such that they different symbol durations coexist.

Abstract: Channel and interference measurement in long term evolution (LTE)/LTE-Advanced (LTE-A) networks including unlicensed spectrum is discussed in which a user equipment (UE) detects a reference signal from a serving base station over a carrier of a shared spectrum for measurement. The reference signal may be a channel usage beacon signal (CUBS) transmitted by the serving base station prior to transmission or may be a specific channel state information (CSI) reference signal transmitted in the first subframe of a transmission frame. The UE generates a fast CSI feedback report based on the measured reference signal and transmits it to the serving base station. The fast CSI feedback report is received quickly enough by the serving base station such that the base station may apply the CSI feedback to additional transmissions in subsequent subframes within the same transmission frame.

Abstract: Techniques are described for wireless communication. An orthogonal frequency-division multiple access (OFDMA) configuration of an uplink channel is identified for communications in an unlicensed radio frequency spectrum band. An OFDMA waveform is generated based on the identified OFDMA configuration. The OFDMA waveform is communicated in a signal in the unlicensed radio frequency spectrum band. A virtual cell identifier of a first base station may be associated with transmissions between the first base station and a first user equipment (UE). A set of common resource blocks may be identified for transmission of a demodulation reference signal (DM-RS) between the first base station and the first UE. A configuration of an uplink channel may be dynamically selected for uplink communications in an unlicensed radio frequency spectrum band. A waveform may be generated based on the selected configuration. The waveform may be communicated in a signal in the unlicensed radio frequency spectrum band.

Abstract: Channel state information (CSI) feedback in long term evolution (LTE) and LTE-Advanced (LTE-A) networks including unlicensed spectrum is disclosed in which a base station obtains clear channel assessment (CCA) result information from neighboring base stations, either directly or by determining such results from measurement or reports from user equipment (UE) served by the base station. The base station may then generate control signaling based on the CCA result information for transmission to the one or more UEs served by the base station.

Abstract: Channel state information (CSI) feedback in long term evolution (LTE) and LTE-Advanced (LTE-A) networks including contention-based shared unlicensed spectrum is disclosed in which a user equipment (UE) identifies at least one carrier utilizing a contention based radio frequency spectrum. The UE detects a transmission signal indicative of clear channel assessment (CCA) result information for the carrier and determines whether a reference signal for channel state information measurement is present in a subframe based on the detected transmission signal. The UE would transmit a measurement report based on this presence determination of the reference signal.

Abstract: Aspects of the present disclosure relate to techniques for network assisted interference cancellation (NAIC). An example method generally includes receiving network assisted interference cancellation (NAIC) information from a potentially interfering neighbor base station, and performing interference cancellation, suppression or mitigation when processing a signal from a serving base station using the NAIC information.

Abstract: Methods and apparatus for wireless communication are described. A method may include receiving at a user equipment (UE) a number of allocated interlaces for an uplink transmission over a shared spectrum, each of which may include a plurality of non-contiguous resource blocks (RB) of the shared spectrum. In some cases, the number of allocated interlaces is unsupported by joint interlace precoding hardware of the UE and the allocated interlaces may be partitioned into subsets of interlaces which may be a size supported by the joint interlace precoding hardware. Reference signals may be generated for the RBs of the allocated interlaces according to a reference signal sequence based on an ordering of the RBs for the allocated interlaces within the shared spectrum.

Abstract: Techniques are described for downlink coordinated multi-point (CoMP) procedures for access to a contention-based radio frequency spectrum band. A base station performs a contention procedure, such as a clear channel assessment (CCA) procedure, for access to the radio frequency spectrum band. The base station determines whether contention has been won for a time period, and communicates whether or not contention has been won to other base stations in a CoMP cooperating set. Based on the information exchanged between base stations in the CoMP cooperating set, coordinated communications is initiated to a UE with two or more of the base stations in the CoMP cooperating set.

Abstract: Certain aspects of the present disclosure provide methods, apparatus, and computer-program products for improving network loading (e.g., by enabling inter-frequency handover and/or traffic offloading between neighboring base stations). In aspects, the proposed methods may include transmitting a beacon signal on a frequency (e.g., carrier frequency) other than the frequency currently used by a base station. The base station may select a cell identity (ID) and transmit one or more beacon signals on the frequency using the selected cell ID. The beacon signal may be used to decide whether or not to perform an inter-frequency handover.

Abstract: Suppression of serving cell transmissions directed to second-served UEs may improve channel estimation of a serving cell or a neighbor cell. This may include using scheduling information for second-served UEs to suppress serving cell signals intended for second-served UEs having overlapping MIMO transmissions. Alternatively, this scheduling information may aid in suppressing a serving cell signal for a second-served UE to improve channel estimation of a neighbor cell. Various embodiments described herein, include implementations and techniques to aid channel estimation, and signal scheduling information to a first-served UE to aid in suppression of serving cell signals for second-served UEs.

Abstract: Certain aspects of the present disclosure relate to techniques for aggregating data from a wireless wide area network (WWAN) and wireless local area network (WLAN). In some aspects, a packet convergence entity (e.g., PDCP layer entity) communicates with first and second radio access technology (RAT) links. The packet convergence entity may determine from which of the first and second RAT links a data packet is received and may monitor a sequence number value of each of the received data packets. The packet convergence entity may perform one or more actions based on a determination that the data packets are received out of order. For example, the packet convergence entity may deliver the data packets to an upper layer entity as they are received (e.g., in order or out of order), may reorder the data packets and ignore data packet losses, and/or may request retransmissions of missing data packets.

Abstract: Design of channel usage beacon signals (CUBS) in cooperative networks is disclosed. After detecting a clear channel assessment (CCA), a transmitter selects a configuration of a CUBS associated with the transmitter based on the CCA opportunity assigned to the network. The configuration of the CUBS associated with the transmitter may include a set of frequency subcarriers for CUBS transmissions. The transmitter transmits the CUBS according to transmission characteristics based on the CCA opportunity. In additional aspects, randomization may be introduced into the frequency subcarrier allocations of CUBS configurations where the transmitter receives assignment of virtual frequency subcarriers for CUBS transmissions and maps the virtual subcarrier to physical frequency subcarriers for CUBS transmission. Additional aspects allow for pattern offset values to be determined independently from the transmitter cell identifier.

Abstract: Management of shared transmission resources is disclosed for multiple radio access networks (RANs) sharing access to a finite number of transmission slots. Multiple permutations of slot assignments are configured in which each competing network is assigned a specific slot in each permutation. The sequence of permutations provides a fair distribution of spectrum access by the competing networks, such that in each permutation of the permutation sequence, networks assigned to lower priority slots may be assigned to higher priority slots in later permutations.

Abstract: A method, a computer program product, and an apparatus are provided. The apparatus may be a UE. The UE receives an information block from a first base station while camped on a second base station. In an aspect, the information block includes an indication of a random access configuration for performing at least a part of a random access procedure. The UE determines to reselect to the first base station from the second base station. The UE performs at least a part of a random access procedure with the first base station based on the indicated random access configuration to reselect from a second base station to the first base station.

Abstract: Methods, apparatuses, systems, and devices are described for wireless communication. In one method, at least a first carrier may be monitored for an indication of a clear channel assessment (CCA) for a second carrier in a shared spectrum, and communication may take place using the second carrier based on the indication. In another method, a CCA may be performed for a second carrier second carrier of a shared spectrum, and an indication of the CCA for the second carrier may be transmitted on a first carrier.

Abstract: Certain aspects of the present disclosure relate to techniques that may help address issues in wireless communications systems that utilize unlicensed radio frequency spectrum bands. For example, the techniques presented herein may be used in systems where frames transmitted in licensed and/or un-licensed component carriers are not synchronous.

Abstract: Methods, apparatuses, systems, and devices are described for wireless communication. In one method, a control format indicator value for a frame may be received over a physical carrier in a shared spectrum. Based on the control format indicator value, a number of subframes of the frame to be used by a base station for downlink transmissions over the physical carrier may be determined. The control format indicator value may indicate an end of transmission, if data is to be transmitted during the frame, a number of subframes to be used for transmission, or whether the current subframe is the final subframe used for transmission. In some cases, a user equipment (UE) may use the control format indicator value to determine a sleep schedule. Further, ACK/NACK transmissions by a UE may be scheduled based on the control format indicator value.

Abstract: The subject technology provides for performing clear channel assessment (CCA) in LTE-U. Transmissions may be monitored in a resource reserved for CCA. An energy of the transmissions is detected over a shorter duration than an assigned slot in the resource reserved for CCA. A beacon may be transmitted in a slot assigned to a wireless entity for CCA in response to detecting a clear channel based on the monitoring. In another aspect, a beacon transmission for CCA and a timing for the monitoring are adapted in response to detecting the transmissions for a consecutive number of CCA periods. Further, the subject technology provides for adjusting to a maximum power for transmission of a beacon in a slot assigned to a mobile station for CCA in response to detecting a clear channel based on the monitoring.

Abstract: Techniques are described for wireless communications. A first subframe structure having a first subframe duration for communicating in a first carrier may be determined. A second subframe structure having a second subframe duration for communicating in a second carrier may also be determined. At least the second subframe structure having the second subframe duration may be used to communicate with at least one node.