Transmission quality is improved in an environment in which direct waves dominate in a transmission method for transmitting a plurality of modulated signals from a plurality of antennas at the same time. All data symbols used in data transmission of a modulated signal are precoded by hopping between precoding matrices so that the precoding matrix used to precode each data symbol and the precoding matrices used to precode data symbols that are adjacent to the data symbol in the frequency domain and the time domain all differ. A modulated signal with such data symbols arranged therein is transmitted.

Certain aspects of the present disclosure relate to methods and apparatus for channel-war polar code construction.

The system and method for maintaining communications in a cellular network provides for automatically generating a bundle of partially overlapping beams when the primary link between a base station (BS) and a mobile station (MS) degrades so that the signal-to-noise ratio (SNR) of a received transmission falls below a defined threshold. The overlapping beams are generated by a beamformer having a circular array of antennas, the array being divided into groups radiating the signal in adjacent but partially overlapping sectors at an amplitude determined by extended Hamming codes having zero cross correlation. The bundle is radiated over a 360° pattern so that it overlaps the blocked signal. The MS demodulates and retrieves received signals having the highest correlation. The recovery time is quicker than conventional systems and methods, e.g., 200 microseconds when the MS uses a narrow pencil beam (5° beamwidth).

A terminal apparatus mounted on a movable body is provided to communicate with an external communication apparatus outside the movable body. The terminal apparatus includes an antenna, and a communicator device. The antenna includes a plurality of antenna elements to be arranged along a traveling direction of the movable body. The communicator device is configured to communicate with the external communication apparatus using a communicating antenna element that is at least one of the plurality of antenna elements. The communicating antenna element is selected from the plurality of antenna elements so as to belong to a specified region. The specified region is defined by propagation environment information of an electric wave propagation path of a signal transmitted to and received from the external communication apparatus.

A user equipment (UE) is configured to vary a number of chains in uplink or downlink communications with a base station (BS). The UE includes a processor coupled to a transceiver. The processor is configured to: identify a full-chain beam for a downlink reception based on a beam sweeping; determine a number of activated chains for an uplink transmission; and determine a sub-chain uplink transmission beam.

An apparatus includes a first communication device with multiple antennas, operably coupled to a processor and configured to access a codebook of transformation matrices. The processor generates a set of symbols based on an incoming data, and applies a permutation to each of the symbols to produce a set of permuted symbols. The processor transforms each of the permuted symbols based on at least one primitive transformation matrix, to produce a set of transformed symbols. The processor applies, to each of the transformed symbols, a precode matrix selected from the codebook of transformation matrices to produce a set of precoded symbols. The codebook of transformation matrices is accessible to a second communication device. The processor sends a signal to cause transmission, to the second communication device, of multiple signals, each representing a precoded symbol from the set of precoded symbols, each of the signals transmitted using a unique antenna from the plurality of antennas.

A network entity comprises a plurality of antenna elements arranged in one or more two dimensional (2D) arrays having one or more columns and rows. The network entity configured to determine at least one set of one or more precoding vectors related to the plurality of antenna elements, wherein each set of precoding vectors is associated with a different Kronecker product tradeoff parameter L≥1; and transmit, at least one set of a plurality of Cell Specific Reference Signals (CRS) to be used to estimate channel state information (CSI) based on the at least one set of precoding vectors and/or at least one Kronecker product tradeoff parameter L.

A method of applying rank two transmission from a plurality of sets of coherent antennas of a user equipment (UE) in a wireless communication system includes: transmitting two information streams using a first set from the plurality of sets of coherent antennas of the UE; and transmitting the two information streams using a second set from the plurality of sets of the coherent antennas of the UE. The first set and the second set are incoherent with respect to each other. The two information streams are common to the first set and the second set.

A method, a computer-readable medium, and an apparatus are provided that enable use of a full transmission power for a UE having a first set of coherent antenna ports that is non-coherent to a second set of coherent antenna ports. The apparatus determines a transmission power for a physical uplink shared channel (PUSCH) transmission from at least one antenna port including splitting the transmission power among multiple antenna ports having non-zero power without scaling the transmission power, and wherein the UE includes at least a first antenna port that is non-coherent to a second antenna port. Then, the apparatus transmits the PUSCH transmission using the determined transmission power.

Embodiments of the present disclosure provide a method of processing received signal using a massive MIMO base station (BS). The BS comprises a radio unit (RU), a distributed unit (DU) and an interface. The method comprises receiving a plurality of signals corresponding to the plurality of antennas, said signals comprises at least one of data signals, demodulation reference signals (DMRS) and sounding reference signals (SRS). The RU or DU performs a grouping operation on a subset of the plurality of signals corresponding to a subset of antennas to generate signal groups. The RU performs a first stage filtering on the signals associated with each group using group specific filters to obtain group specific filtered signals. The DU performs a second stage filtering on the group specific filtered signals to obtain second stage filtered signals.