H04L25/0224

CHANNEL ESTIMATION USING COMPOSITE SUBCARRIERS AND COMBINED PILOTS
20180013592 · 2018-01-11 ·

Techniques for minimum-mean-square-error (MMSE) channel estimator using channel-dependent composite subcarriers and combined pilots reduce computational complexity and memory usage while still achieving near optimum performance. A set of interpolation filters, that are pre-calculated for different radio propagation environments, e.g., channel state information, are stored in look up tables at the receiver and used to interpolate channel estimates for combined pilots to obtain channel estimates for individual subcarriers.

WIRELESS COMMUNICATION DEVICE AND WIRELESS COMMUNICATION METHOD
20180013478 · 2018-01-11 · ·

A wireless communication device and a wireless communication method. The wireless communication device includes one or more processors. The processor is configured to estimate an equivalent channel from a base station to user equipment based on a user equipment specific reference signal from the base station, and generate, according to the estimated equivalent channel, a channel state indication used to be fed back to the base station.

Uplink multi-user sounding for WLAN

A WLAN AP includes an array of antennas, a transceiver and a processor. The transceiver is configured to transmit via the array of antennas downlink packets to WLAN STAs, and to receive uplink packets from the STAs. The processor is coupled to the transceiver and is configured to send a request to a plurality of the STAs to transmit a respective plurality of channel-sounding packets corresponding to the plurality of STAs, to receive the plurality of channel-sounding packets from the plurality of STAs in response to the request, to compute, based on the received plurality of channel-sounding packets, a beamforming matrix that defines subsequent transmission beams aimed toward at least a subset of the plurality of STAs, and to transmit one or more downlink data packets to one or more of the STAs via the array of antennas, in accordance with the beamforming matrix.

Measurement apparatus and measurement method

An EVM measurement value is appropriately determined while CPE/ICI correction is taken into account. In a measurement apparatus (300), an EVM measurer (305) measures a modulation quality of a signal transmitted from a transmission apparatus. An EVM determiner (306) determines whether or not the measurement value of the modulation quality is equal to or less than a first requirement value, in a case where correction relating to a phase noise of the transmission apparatus is necessary in a reception apparatus. The first requirement value herein is higher than a second requirement value used in the determination of the measurement value in a case where the correction relating to the phase noise of the transmission apparatus is unnecessary in the reception apparatus.

COMMUNICATION SYSTEM AND COMMUNICATION METHOD

Provided is a wireless communication apparatus wherein channel estimation accuracy is improved while keeping the position of each bit in a frame, even when a modulation system having a large modulation multiple value is used for a data symbol. In the wireless communication apparatus, an encoding section encodes and outputs transmitting data to a bit converting section, and the bit converting section converts at least one bit of a plurality of bits constituting a data symbol to be used for channel estimation, among the encoded bit strings, into ‘1’ or ‘0’ and outputs it to a modulating section. The modulating section modulates the bit string inputted from the bit converting section by using a single modulation mapper and a plurality of data symbols are generated.

SYSTEM AND METHOD FOR DETECTING OF CHANNEL CONDITIONS AND CHANNEL ESTIMATION IN AN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING (OFDM) RECEIVER
20230239177 · 2023-07-27 ·

In one aspect, an apparatus includes: a front end circuit to receive and process incoming radio frequency (RF) signals into orthogonal frequency division multiplexing (OFDM) samples; a fast Fourier transform (FFT) engine to receive and convert the OFDM samples into frequency domain sub-carriers; a demodulator to demodulate the frequency domain sub-carriers; a channel estimator to: compute a first pilot channel estimate for a first channel condition comprising a flat channel condition and a second pilot channel estimate for a second channel condition comprising a selective channel condition based on a first set of pilot sub-carriers of the frequency domain sub-carriers; and select one of the first and second pilot channel estimates using the first and second pilot channel estimate; and a control circuit to configure at least the demodulator based at least in part on the selected first or second pilot channel estimate.

EXPLORATION OF INACTIVE RANKS OR INACTIVE PRECODERS

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive a signal. The UE may measure the signal to explore one or more inactive ranks or inactive precoders. The UE may transmit, based at least in part on the measuring, a report that includes channel state information for at least one of the one or more inactive ranks or inactive precoders. Numerous other aspects are described.

Data Processing Apparatus and Method, Base Station, and Storage Medium
20230024048 · 2023-01-26 ·

A data processing apparatus and method, a base station, and a storage medium are provided. The apparatus includes: a processor, configured to determine a computation parallelism degree according to the number of antennas and pilot frequency information, acquire antenna data and channel estimation matrices of respective users, and store the antenna data and the channel estimation matrices in groups in a memory, and determine, according to the computation parallelism degree, target antenna data processed in parallel by an arithmetic unit in a single computation, wherein the target antenna data is part of the antenna data of the respective users; the memory, configured to store the antenna data and the channel estimation matrices in groups, and output the target antenna data and the channel estimation matrices to the arithmetic unit; and the arithmetic unit, configured to compute user data based on the target antenna data and the channel estimation matrices.

DEMODULATION REFERENCE SIGNAL TIME DOMAIN BUNDLING

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, from a base station, information indicating that demodulation reference signal (DMRS) time domain bundling is enabled. The UE may determine a time domain bundling configuration based at least in part on the information indicating that the DMRS time domain bundling is enabled. Accordingly, in some aspects, the UE may perform channel estimation based at least in part on DMRSs received in different physical downlink control channel monitoring occasions based at least in part on the time domain bundling configuration. Numerous other aspects are provided.

Terminal device, base station device, and communication method for setting TTI channel
11711165 · 2023-07-25 · ·

[Object] To provide a terminal device capable of efficiently performing communication in a communication system in which a base station device and the terminal device communicate with each other. [Solution] A terminal device that communicates with a base station device includes: a higher layer processing unit configured to set an STTI channel setting through signaling of a higher layer from the base station device; and a receiving unit configured to receive a first PDSCH in a case in which the STTI channel setting is not set and receive a second PDSCH in a case in which the STTI channel setting is set. The first PDCCH is mapped to one or more resource blocks, the second PDCCH is mapped to one or more sub resource blocks, and the second PDSCH is demodulated using a reference signal mapped to a symbol including the sub resource block or a resource element before the symbol.