An apparatus for detecting difference in operating characteristics of a main circuit by using a replica circuit is presented. In one exemplary case, a sensed difference in operating characteristics of the two circuits is used to drive a tuning control loop to minimize the sensed difference. In another exemplary case, several replica circuits of the main circuit are used, where each is isolated from one or more operating variables that affect the operating characteristic of the main circuit. Each replica circuit can be used for sensing a different operating characteristic, or, two replica circuits can be combined to sense a same operating characteristic.

Provided is a method performed by a user equipment (UE) in a wireless communication system. The method includes performing communication with a base station based on a full-duplex mode, transmitting, to the base station, a first message for requesting a duration for calibration of a circuit for analog self-interference cancellation (SIC), receiving, from the base station, a second message for allocating the duration, and performing the calibration of the circuit during the duration. Herein, during the duration, the UE is controlled to operate based on a half-duplex mode.

Provided is a method performed by a user equipment (UE) in a wireless communication system. The method includes performing communication with a base station based on a full-duplex mode, transmitting, to the base station, a first message for requesting a duration for calibration of a circuit for analog self-interference cancellation (SIC), receiving, from the base station, a second message for allocating the duration, and performing the calibration of the circuit during the duration. Herein, during the duration, the UE is controlled to operate based on a half-duplex mode.

Systems and methods for improving testing and/or calibration efficiency of radio frequency system. In some embodiments, a testing system includes a beamformer radio frequency system, in which the beamformer radio frequency system includes first transceiver circuitry and a first plurality of antennas coupled to the first transceiver circuitry, a beamformee radio frequency system, in which the beamformee radio frequency system includes second transceiver circuitry and a second plurality of antennas coupled to the second transceiver circuitry, one or more wired connections coupled between the first transceiver circuitry of the beamformer radio frequency system and the second transceiver circuitry of the beamformee radio frequency system, in which each of the one or more wired connections bypasses the first plurality of antennas of the first radio frequency system and the second plurality of antennas of the second radio frequency system.

Systems and methods for improving testing and/or calibration efficiency of radio frequency system. In some embodiments, a testing system includes a beamformer radio frequency system, in which the beamformer radio frequency system includes first transceiver circuitry and a first plurality of antennas coupled to the first transceiver circuitry, a beamformee radio frequency system, in which the beamformee radio frequency system includes second transceiver circuitry and a second plurality of antennas coupled to the second transceiver circuitry, one or more wired connections coupled between the first transceiver circuitry of the beamformer radio frequency system and the second transceiver circuitry of the beamformee radio frequency system, in which each of the one or more wired connections bypasses the first plurality of antennas of the first radio frequency system and the second plurality of antennas of the second radio frequency system.

A calibration circuit 2 according to the present disclosure is a calibration circuit 2 in a radio base station system 1 including a remote unit part 10 and a plurality of distributed antenna parts 20 connected to the remote unit part 10 through a plurality of respective cables, the calibration circuit 2 including: a detection unit 2a configured to detect a plurality of local oscillation signals that are output from a local oscillator 13 of the remote unit part 10 and are respectively reflected from the plurality of distributed antenna parts 20 through the plurality of cables; and a phase adjustment unit 2b configured to adjust a phase of each of the plurality of local oscillation signals output through the plurality of respective cables from the remote unit part 10 based on a result of the detection.

A calibration circuit 2 according to the present disclosure is a calibration circuit 2 in a radio base station system 1 including a remote unit part 10 and a plurality of distributed antenna parts 20 connected to the remote unit part 10 through a plurality of respective cables, the calibration circuit 2 including: a detection unit 2a configured to detect a plurality of local oscillation signals that are output from a local oscillator 13 of the remote unit part 10 and are respectively reflected from the plurality of distributed antenna parts 20 through the plurality of cables; and a phase adjustment unit 2b configured to adjust a phase of each of the plurality of local oscillation signals output through the plurality of respective cables from the remote unit part 10 based on a result of the detection.

The application discloses a transceiver, including a calibration signal generation unit, a transmission unit, a receiving unit and a control unit. The calibration signal generation unit generates test signal to the transmission unit in a phase calibration mode. The receiving unit generates a digital receiving signal. The control unit calculates a phase difference between the digital receiving signal and a given reference phase and selectively adjust the transmission unit or the receiving unit accordingly. The application discloses a transceiver calibration method as well.

The application discloses a transceiver, including a calibration signal generation unit, a transmission unit, a receiving unit and a control unit. The calibration signal generation unit generates test signal to the transmission unit in a phase calibration mode. The receiving unit generates a digital receiving signal. The control unit calculates a phase difference between the digital receiving signal and a given reference phase and selectively adjust the transmission unit or the receiving unit accordingly. The application discloses a transceiver calibration method as well.

This document describes techniques and systems for independent transmit and receive channel calibration for multiple-input multiple-output (MIMO) systems. Antenna responses are collected from each virtual channel of a MIMO system at an angle respective to an object. The transmit components and the receive components of the virtual channels are separated and organized into vectors (one for the transmit components and one for the receive components). Calibration values for elements of the vectors are computed and maintained in a transmit calibration matrix and a receive calibration matrix, respectively. Together, the transmit calibration matrix and the receive calibration matrix may include fewer elements than a calibration matrix for the virtual channels and, therefore, may require less memory and fewer computations to calibrate a MIMO system than using other calibration techniques. As such, described is a less expensive and less complex way to calibrate MIMO system by accurately approximating an ideal antenna array.