A repeater generates repetition signals by repeating uplink signals over a plurality of subframes; controller sets a timing for transmitting the repetition signals, based on information indicating a transmission candidate subframe for a sounding reference signal used for measuring an uplink reception quality; and a transmitter transmits the repetition signals at the set timing.

A system for reflecting an RF signal comprises a plurality of antenna units (2) configured to receive and passively reflect the RF signal, and a reference antenna (6′). Each antenna unit (2) comprises a respective phase shifter (8) operable to adjustably impose a phase change on the RF signal before reflection. The system may be a Large Intelligent Surface (LIS) and the antenna units may be included in an arrangement of separate panel devices. A control system (20) is configured to operate the respective phase shifter (8) to phase align a first analog antenna signal (ASn) with a first analog reference signal (REF), which are received by the respective antenna unit (2) and the reference antenna (6′), respectively, in response to a first RF signal; determine, for the respective phase shifter (8), a first phase setting resulting in phase alignment, and store the first phase setting. The first phase settings enable the system to perform beamforming in reception and/or reflection essentially without power consumption.

An antenna is provided and characterized by searching a look-up table for emission angle information according to an incident angle of a radio frequency input signal and driving an antenna array to emit a radio frequency output signal in a direction corresponding to an incident direction of the radio frequency input signal according to the emission angle information.

Disclosed herein is a wireless communication system. More particularly, disclosed herein is a method and apparatus for coordinating and reducing inter-cell interference in a wireless communication system. A method of transmitting channel state information (CSI) measurement resource information by a base station includes determining first and second subframe sets, in which CSI measurement will be performed, among a plurality of downlink subframes, transmitting information indicating the first and second subframe sets to a terminal, and receiving the CSI of each of the first and second subframe sets from the terminal. A subframe belonging to the first subframe set and a subframe belonging to the second subframe set do not overlap, and some of the plurality of subframes do not belong to either of the first and second subframe sets.

A control node for an array antenna configured so as to apply an attenuation and a phase shift to a radiofrequency signal on the basis of a control signal, to a beamforming network, to an array antenna and to a satellite includes the control node. It comprises a quadratic divider that delivers an in-phase signal and a quadrature signal on separate transmission channels, a combiner configured so as to sum the signals transmitted on two of the transmission channels, each transmission channel comprising at least: one attenuation cell activated on the basis of the value of a dedicated bit of the control signal, and one phase shift cell configured so as to apply a fixed phase shift, activated on the basis of the result of combinational logic implemented on bits of the control signal.

This disclosure provides methods, devices and systems for wireless communication, and particularly, methods, devices and systems for implementing a joint transmission feature in a wireless communication system. Using the joint transmission feature, multiple access points (APs) may use an aggregated collection of antennas of multiple APs to simultaneously transmit a joint beamformed transmission to one or more stations (STAs). The techniques in this disclosure may prevent or reduce variations in relative gain adjustments by the APs that could otherwise negatively impact the joint transmission. In some implementations, a network device may determine a normalized gain adjustment value based on power parameters associated with each of the multiple APs. In some other implementations, each AP may determine the normalized gain adjustment value based on power parameters shared between the APs.

A method of processing incoming signals, such as RF signals, includes receiving the incoming RF signals at two (or more) spatially-separated receivers, then processing the signals to determine a phase lag between the two signals. This allows a presumed location of the signal source to be determined, based on the time difference of arrival (TDOA) of signals at the separated receivers. This can be used to produce a phase adjustment of one of the signals, allowing the signals to be coherently summed. The coherently summed combined signal is then examined for instances where a threshold magnitude is exceeded. This information is then used to create a blanking mask, which is then employed as a filter to incoming signals, to blank out non-coherent signals, such as noise and extraneous signals from sources that are not of interest. The blanked signal train is then examined/analyzed for constant pulse repetitions.

In described examples, a quadrature phase shifter includes digitally programmable phase shifter networks for generating leading and lagging output signals in quadrature. The phase shifter networks include passive components for reactively inducing phase shifts, which need not consume active power. Output currents from the transistors coupled to the phase shifter networks are substantially in quadrature and can be made further accurate by adjusted by a weight function implemented using current steering elements. Example low-loss quadrature phase shifters described herein can be functionally integrated to provide low-power, low-noise up/down mixers, vector modulators and transceiver front-ends for millimeter wavelength (mmwave) communication systems.

A method for mitigating inter-mode interference (IMI) caused by antenna misalignment in an orbital angular momentum (OAM) mode multiplexing (OAM-MM) system and detecting a signal in an OAM beam. The method includes receiving an OAM beam bearing a signal, determining a phase-shifting value based on at least one of a type of the antenna misalignment and one or more antenna-misalignment parameters, wherein the phase-shifting value belongs to a beamforming (BF) codebook, shifting the phase of the received OAM beam using the determined phase-shifting value, and detecting the signal from the phase-shifted OAM beam.

This disclosure provides methods, devices, and systems for a wireless communication device to perform signal phase rotation. In some implementations, the wireless communication device may determine a number of phase rotation parameters to be applied to a number of tones of a transmission signal. In some aspects, each of the phase rotation parameters indicates a phase rotation to be applied to each of the tones according to a carrier index range for each of the tones and a bandwidth mode for the transmission signal. In some implementations, the wireless communication device may apply the phase rotation parameters to respective ones of the tones according to the specified phase rotations and the carrier index ranges, and transmit the transmission signal from the wireless communication device according to the applied phase rotation parameters.