Methods, systems, and devices for wireless communications are described. A user equipment (UE) may determine to operate in an antenna switch diversity mode to transmit an uplink signal according to an antenna switching pattern, the antenna switching pattern comprising switching between a first transmit chain coupled to a first antenna and a second transmit chain coupled to a second antenna. The UE may transmit at least a first portion of the uplink signal using the first transmit chain coupled to the first antenna, the first transmit chain coupled to the first antenna. The UE may transmit at least a second portion of the uplink signal using the second transmit chain coupled to the second antenna, the second transmit chain coupled to the second antenna.

Provided are M signal processors that respectively generate modulated signals for M reception apparatuses (where M is an integer equal to 2 or greater), a multiplexing signal processor, and N antenna sections (where N is an integer equal to 1 or greater). When transmitting multiple streams, each of the M signal processors generates two mapped signals, generates first and second precoded signals by precoding the two mapped signals, periodically changes the phase of signal points in the IQ plane with respect to the second precoded signal, outputs the phase-changed signal, and outputs the first precoded signal and the phase-changed second precoded signal as two modulated signals. When transmitting a single stream, each of the M signal processor outputs a single modulated signal. The multiplexing signal processor multiplexes the modulated signals output from the M signal processors, and generates N multiplexed signals. The N antenna sections respectively transmit the N multiplexed signals.

Provided, according to various embodiments, are a method for performing, by a terminal, communication according to cyclic delay diversity (CDD) using multiple antennas in a wireless communication system and an apparatus therefor. Disclosed are a method for performing communication according to cyclic delay diversity (CDD) and an apparatus therefor, the method comprising the steps of: determining a delay range of a delay value for CDD on the basis of a moving speed of a terminal; determining the delay value of the CDD within a set delay range; and transmitting a cyclically delayed signal to a target terminal, according to the determined delay value, wherein the preset delay range is determined on the basis of the moving speed of the terminal.

Various embodiments of the present technology relate generally to wireless power systems. More specifically, some embodiments relate to the use of time reversal techniques utilizing time diversity (e.g., different multipath arrivals at the same antenna) to achieve coherency from the same transmission node. For example, instead of initiating outgoing transmissions (e.g., power signals) at the same time, various embodiments can initiate the outgoing signals from the various antennas in a staggered timing that is a reversal of the arrival times of an incoming signal. As a result of staggering the start of the outgoing signals, the signals will arrive at the destination at approximately the same time even though they have traveled different paths having different propagation delays.

A transmission method includes generating a first precoded signal and a second precoded signal by performing a precoding process on a first baseband signal and a second baseband signal, outputting a third signal by inserting a pilot signal into the first precoded signal, outputting a fourth signal by applying a first phase change to the second precoded signal, outputting a fifth signal by inserting a pilot signal into the fourth signal, and outputting a sixth signal by applying a second phase change to the fifth signal.

Embodiments of the present disclosure disclose an uplink transmission method, an uplink transmission scheduling method and a device. The uplink transmission method is applied to a terminal and includes: performing delay processing of an uplink signal on multiple antenna ports and then transmitting the uplink signal.

Aspects of the techniques and apparatuses described herein provide an intra slot antenna diversity scheme that a user equipment (UE) may use to transmit uplink communications while mitigating antenna imbalance. In an intra slot antenna diversity scheme, a UE transmits an uplink communication by transmitting a first portion of the uplink transmission in a first part of a slot using a first subset of antennas and a second portion of the uplink communication in a second part of the slot using a second subset of antennas. A decision to apply an intra slot antenna diversity scheme may be made by a network node such as a base station. Numerous other aspects are described.

Design of precoding and feedback for user equipment (UE)-specific reference signals (UE-RS)-based open-loop and semi-open-loop multiple input, multiple output (MIMO) systems is discussed. Aspects of the present disclosure provide for sub-resource block (RB) random precoding that allows for greater diversity gain in a lower bandwidth. In addition, the recoding may be performed using resource element (RE)-level layer shifting that provides for a number of precoders to be assigned to a number of layers for every such continuous subcarrier. As such, two codewords may experience the same effective channel quality with channel quality indicators (CQI) being averaged across all of the layers.

Provided are M signal processors that respectively generate modulated signals for M reception apparatuses (where M is an integer equal to 2 or greater), a multiplexing signal processor, and N antenna sections (where N is an integer equal to 1 or greater). When transmitting multiple streams, each of the M signal processors generates two mapped signals, generates first and second precoded signals by precoding the two mapped signals, periodically changes the phase of signal points in the IQ plane with respect to the second precoded signal, outputs the phase-changed signal, and outputs the first precoded signal and the phase-changed second precoded signal as two modulated signals. When transmitting a single stream, each of the M signal processor outputs a single modulated signal. The multiplexing signal processor multiplexes the modulated signals output from the M signal processors, and generates N multiplexed signals. The N antenna sections respectively transmit the N multiplexed signals.

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.