The present disclosure relates to the field of mobile communications technologies, and in particular, to a signal transmission method and an apparatus. In the signal transmission method, user equipment receives, from a base station, first information in a physical downlink control channel, where the first information is used for determining precoding information of a sounding reference signal (SRS). The user equipment determines precoding information of the SRS based on the first information. The user equipment performs, based on the precoding information, precoding on the SRS to generate a precoded signal, and sends the precoded signal to the base station.

The present disclosure provides a terminal and a base station in a wireless communication system. The terminal may include a control unit configured to input a downlink channel to a neural network of the terminal; and the control unit further configured to control the neural network of the terminal to process the input and output feedback information.

A method of updating spatial filters in a radio network comprising at least two transmit nodes each in radio communication with at least one receive node on a Multiple-Input Multiple-Output (MIMO) radio channel, comprises transmitting, from the respective transmit node, first reference signals precoded by a first spatial filter of the respective transmit node; and receiving, from the receive nodes, second reference signals that are precoded using a second spatial filter of the respective receive node and an error matrix of the respective receive node. The second spatial filter depends on a channel estimate based on the transmitted first reference signals. The error matrix is indicative of an error of the first and second spatial filters in equalizing the MIMO radio channel. The method further comprises recomputing, for each of the at least one receive node in radio communication with the respective transmit node, the error matrix of the respective receive node; and updating the first spatial filter of the respective transmit node using the recomputed error matrix.

Methods, apparatus, and systems for wireless communications are described. Example methods, devices, and systems are described that utilize a precoding matrix indicator (PMI) computed based at least in part on first signals received via a first cell and on second signals received via a second cell. Information in a measurement information message may be used as part of computing a PMI. The measurement information message may indicate resources of a first cell and a second cell for use in computing the PMI. A wireless device may receive first signals via the first cell and second signals via the second cell based on information in the measurement information message, and may use these signals to compute the PMI. The computed PMI may be used in communications with a base station. For example, the wireless device may receive a packet beamformed employing the computed PMI.

A transmission scheme for transmitting a first modulated signal and a second modulated signal in the same frequency at the same time. According to the transmission scheme, a precoding weight multiplying unit multiplies a precoding weight by a baseband signal after a first mapping and a baseband signal after a second mapping and outputs the first modulated signal and the second modulated signal. In the precoding weight multiplying unit, precoding weights are regularly hopped.

Various embodiments disclosed herein provide for a base station device that can determine which layers should be mapped to codewords in a multi-layer, multi-antenna transmission. The base station device can transmit reference signals to a user equipment device, with each reference signal associated with a respective codeword to layer mapping combination, and the user equipment can send channel state information associated with each reference signal back to the base station device, and the base station device can rank each combination in terms of spectral efficiency or capacity and/or throughput. The base station device can inform the user equipment of the ranked combinations by sending a bit map with the ranked combinations to the user equipment device.

A communication apparatus comprises a generator that generates frequency resource position information corresponding to a first information which is based on the communication quality information received from user equipments, the frequency resource position information indicating validity or invalidity of the first information for each frequency resource, and a transmitter that transmits the first information, the frequency resource position information and a cell ID which the frequency resource position is applied, to another communication apparatus via a backhaul.

Aspects described herein relate to wireless communications. According to some aspects, a first base station may coordinate with a second base station to select beamforming codewords. The first base station may receive an index indicating beamforming codewords used by a second base station. The first base station may select a beamforming codeword for use in transmitting signals to a wireless device based on the beamforming codeword indicated by the second base station.

Various embodiments disclosed herein provide for a base station device that can determine which layers should be mapped to codewords in a multi-layer, multi-antenna transmission. The base station device can transmit reference signals to a user equipment device, with each reference signal associated with a respective codeword to layer mapping combination, and the user equipment can send channel state information associated with each reference signal back to the base station device, and the base station device can rank each combination in terms of spectral efficiency or capacity and/or throughput. The base station device can inform the user equipment of the ranked combinations by sending a bit map with the ranked combinations to the user equipment device.

A transmission scheme for transmitting a first modulated signal and a second modulated signal in the same frequency at the same time. According to the transmission scheme, a precoding weight multiplying unit multiplies a precoding weight by a baseband signal after a first mapping and a baseband signal after a second mapping and outputs the first modulated signal and the second modulated signal. In the precoding weight multiplying unit, precoding weights are regularly hopped.