Abstract:
Aspects of the disclosure provide a method for beam management at a base station (BS) in a wireless communication system. The method can include transmitting a beam training reference signal (RS) resource configuration from a base station (BS) to a user equipment (UE) in a wireless communication system, transmitting an anchor association index indicating an association between a beam pair link and a set of second transmit beams of the BS, wherein the beam pair link is formed by a first transmit beam of the BS and a receive beam of the UE, transmitting beam training RSs according to the beam training RS resource configuration on the set of second transmit beams, and receiving a measurement report including quality measurements of beamformed channels over the receive beam and a subset of the second transmit beams.
Abstract:
A beam indication (BI) mechanism is proposed to provide user equipment (UE) information of network (NW) beam(s) for later transmission. UE can then select its UE beam(s) for the later transmission based on the BI. In one embodiment, NW provides beam management configuration to UE via Radio Resource Control (RRC) signaling, and then provides beam indication index signaling to UE via MAC-CE or DCI. The beam management configuration comprises a mapping table between network beams and configured reference signal (RS) resources. The beam indication index signaling indicates one or more preferred beam pair links (BPLs). Upon triggering a beam management procedure by the network, UE is able to identify the beam management procedure and selects corresponding UE beam(s) based on the beam management configuration and the beam indication index signaling.
Abstract:
A method of beam failure recovery request (BFRQ) transmission is proposed. In a first step of beam failure detection, UE detects a beam failure condition of the original serving beam. In a second step of new candidate beam identification, UE performs measurements for candidate beam selection. In a third step of beam failure recovery request (BFRQ) transmission, UE transmits a BFRQ message to BS upon the triggering condition for BFRQ transmission is satisfied. In a fourth step of monitoring BS response, UE monitors BS response to decide the success or failure of the BFRQ transmission attempt. In one advantageous aspect, the BFRQ transmission is over dedicated contention-free PRACH or PUCCH resources or over contention-based PRACH resources. Furthermore, a beam failure recovery timer is used to oversee the initiation and the termination of the BFRQ transmission.
Abstract:
A method of beam reciprocity state reporting and uplink beam management in wireless communication systems with beamforming is proposed. In one novel aspect, a UE determines its UE beam reciprocity state and sends a “UE beam reciprocity state” message to a BS, which triggers proper uplink beam management accordingly. The UE beam reciprocity state message can take place when UE tries to register to the network. For example, according to factory setting, UE reports at least “Positive” or “Negative” in this message. Beam reciprocity state can be updated by a “UE beam reciprocity state update” message. An auxiliary information can be transmitted to the BS for UL beam management if UE reports “Negative” for beam reciprocity state. The auxiliary information indicates the uncertainty level of UE beams.
Abstract:
A method of providing spatial diversity for critical data delivery in a beamformed mmWave smallcell is proposed. The proposed spatial diversity scheme offers duplicate or incremental data/signal transmission and reception by using multiple different beams for the same source and destination. The proposed spatial diversity scheme can be combined with other diversity schemes in time, frequency, and code, etc. for the same purpose. In addition, the proposed spatial diversity scheme combines the physical-layer resources associated with the beams with other resources of the same or different protocol layers. By spatial signaling repetition to avoid Radio Link Failure (RLF) and Handover Failure (HOF), mobility robustness can be enhanced. Mission-critical and/or time-critical data delivery can also be achieved without relying on retransmission.
Abstract:
A network control device includes a wireless communications module and a controller. The wireless communications module uses a preferred transmitting beam to communicate with a communications apparatus in one or more downlink opportunities corresponding to the preferred transmitting beam. The controller schedules signal or data to be transmitted in at least one downlink opportunity corresponding to the preferred transmitting beam. When scheduling signal or data to be transmitted, the controller further provides at least one training gap, in which the controller does not schedule any dedicated data to the communications apparatus, in the downlink opportunity corresponding to the preferred transmitting beam.
Abstract:
Inter-cell coordination and beam-aware scanning with end-to-end UE-BS signaling enhancements for robust HO trigger in a beamforming mmWave network is proposed. From the network and the base station perspective, inter-BS control beam coordination is performed, coupled with neighbor-cell information advertisement to facilitate UE-side beam-aware scanning. Inter-BS CB coordination enables a variety of network planning, pre-determined or random, enhanced with UE-reports and dynamic re-coordination to minimize inter-cell interference. From UE perspective, by utilizing the advertised CB information, UE can learn serving cell and neighbor cell CB pattern for beam-aware scanning. Beam-aware scanning enables power saving fast scanning at the UE with beam-aware HO measurement of neighboring and target cells, which reduces HO latency and avoids unnecessary HO.
Abstract:
A beamforming system synchronization architecture is proposed to allow a receiving device to synchronize to a transmitting device in time, frequency, and spatial domain in the most challenging situation with very high pathloss. A detector at the receiving device detects the presence of control beams, synchronizes to the transmission and estimates the channel response by receiving pilot signals. The detector has low complexity when exploiting the structure of the pilot signals. The detector consists of three stages that break down the synchronization procedure into less complicated steps. The detector accurately estimates the parameters required for identifying the transmit device and performing subsequent data communication.
Abstract:
A beamforming system synchronization architecture is proposed to allow a receiving device to synchronize to a transmitting device in time, frequency, and spatial domain in the most challenging situation with very high pathloss. A periodically configured time-frequency resource blocks in which the transmitting device uses the same beamforming weights for its control beam transmission to the receiving device. A pilot signal for each of the control beams is transmitted in each of the periodically configured time-frequency resource blocks. Pilot symbols are inserted into pilot structures and repeated for L times in each pilot structure. The L repetitions can be implemented by one or more Inverse Fast Fourier Transfers (IFFTs) with corresponding one or more cyclic prefix (CP) lengths.