Aspects herein describe increasing density of reference signal transmissions in wireless communications. A plurality of reference signal configurations, each indicating resource elements for one or more antenna ports over which reference signals for the one or more antenna ports are scheduled for transmission, can be received. An association configuration indicating an association between at least two antenna ports as having similar channel characteristics can also be received. A plurality of reference signals can be received in the resource elements corresponding to the at least two antenna ports as indicated in the at least two of the plurality of reference signal configurations, which can be used to perform a channel measurement of the similar channel characteristics of channels of the at least two antenna ports over at least a portion of the plurality of reference signals.

Embodiments described herein provide a system for transmitting high efficiency long term training field (HE-LTF) symbols for multiple wireless spatial streams over a wireless channel. An advanced P-matrix design is used to construct HE-LTF symbols that are processed by a receiver such that channel properties such as channel estimates or carrier phase error are determined prior to receiving all HE-LTF symbols. Tone multiplexing of wireless spatial stream is also used to transmit multiple spatial streams based on an assignment of sets of spatial streams to sets of tones available for transmission, increasing the throughput of the transmission system. The advanced P-matrix design and tone multiplexing are used in combination to achieve calculate channel properties before receiving all HE-LTF symbols while minimizing power fluctuation among the high efficiency short training field symbol and the HE-LTF symbols.

A device location sensing method obtains locations of N devices in a wireless network based on channel state information (CSI). Each device in the wireless network has M antennas arranged in a non-linear manner. To determine the device locations, CSI data mutually detected between every two devices in N devices is obtained and used to calculate an angle difference of arrival (ADoA) set which includes, for every two devices in the N devices relative to each of the other devices in the N devices, an ADoA that is a difference between angles of arrival (AoAs) of the two devices relative to the other device. Relative locations of the N devices are then calculated based on the ADoA set.

A device location sensing method obtains locations of N devices in a wireless network based on channel state information (CSI). Each device in the wireless network has M antennas arranged in a non-linear manner. To determine the device locations, CSI data mutually detected between every two devices in N devices is obtained and used to calculate an angle difference of arrival (ADoA) set which includes, for every two devices in the N devices relative to each of the other devices in the N devices, an ADoA that is a difference between angles of arrival (AoAs) of the two devices relative to the other device. Relative locations of the N devices are then calculated based on the ADoA set.

Aspects of the present disclosure relate to wireless communications, and more particularly, to techniques for use in receiving devices employing at least one iterative process for decoding messages. In certain example aspects, a receiving device may comprise a user equipment (UE) or other like device that may be configured to support device-to-device (D2D) communications, such as vehicle-to-vehicle (V2V) communications, or the like.

Aspects of the present disclosure relate to wireless communications, and more particularly, to techniques for use in receiving devices employing at least one iterative process for decoding messages. In certain example aspects, a receiving device may comprise a user equipment (UE) or other like device that may be configured to support device-to-device (D2D) communications, such as vehicle-to-vehicle (V2V) communications, or the like.

An apparatus and method are provided for using an MLP algorithm to map channel features to an RI and/or a CQI for CSI feedback. The method includes estimating a channel in the communication network for a signal; extracting at least one channel feature related to the estimated channel; determining RI and CQI pairs; inputting, to an MLP network, the extracted at least one channel feature and the RI and CQI pairs; receiving, for each of the RI and CQI pairs, an output of the MLP network, wherein the outputs of the MLP network indicate throughput or spectral efficiency for the electronic device; and selecting an RI and CQI pair of the RI and CQI pairs based on the received outputs.

An apparatus and method are provided for using an MLP algorithm to map channel features to an RI and/or a CQI for CSI feedback. The method includes estimating a channel in the communication network for a signal; extracting at least one channel feature related to the estimated channel; determining RI and CQI pairs; inputting, to an MLP network, the extracted at least one channel feature and the RI and CQI pairs; receiving, for each of the RI and CQI pairs, an output of the MLP network, wherein the outputs of the MLP network indicate throughput or spectral efficiency for the electronic device; and selecting an RI and CQI pair of the RI and CQI pairs based on the received outputs.

Disclosed are a method and apparatus for processing an uplink frequency offset of a communication system. The method on a base station side includes: demodulating a random access message sent by a terminal to obtain an initial Doppler frequency offset of the terminal and delivering the initial Doppler frequency offset to the terminal; receiving an uplink subframe signal sent by the terminal, estimating a residual Doppler frequency offset of the terminal on an uplink, obtaining a frequency retuning amount according to the residual Doppler frequency offset and delivering the frequency retuning amount to the terminal. The method on a terminal side includes: receiving an initial Doppler frequency offset sent by a base station, obtaining an initial uplink transmission frequency according to an initial downlink transmission frequency and the initial Doppler frequency offset and sending an uplink subframe signal; and receiving a frequency retuning amount sent by the base station, and obtaining a transmission frequency of a next uplink transmission according to the frequency retuning amount.

Disclosed are a method and apparatus for processing an uplink frequency offset of a communication system. The method on a base station side includes: demodulating a random access message sent by a terminal to obtain an initial Doppler frequency offset of the terminal and delivering the initial Doppler frequency offset to the terminal; receiving an uplink subframe signal sent by the terminal, estimating a residual Doppler frequency offset of the terminal on an uplink, obtaining a frequency retuning amount according to the residual Doppler frequency offset and delivering the frequency retuning amount to the terminal. The method on a terminal side includes: receiving an initial Doppler frequency offset sent by a base station, obtaining an initial uplink transmission frequency according to an initial downlink transmission frequency and the initial Doppler frequency offset and sending an uplink subframe signal; and receiving a frequency retuning amount sent by the base station, and obtaining a transmission frequency of a next uplink transmission according to the frequency retuning amount.