In some implementations, a MIMO calibrating apparatus may include coupling a plurality of input/output paths of a MIMO antenna panel to a plurality of transmit or receive paths of a MIMO radio panel, and measuring a loss of each of the plurality of input/output paths of the MIMO antenna panel at an input for a common calibration receiver port of the MIMO radio panel. The apparatus may include coupling a calibration feedback network of the MIMO antenna panel to the common calibration receiver port of the MIMO radio panel. The apparatus may include transmitting or receiving at a known power level by the MIMO radio panel, measuring a power output of all transmit or receive paths, and calibrating a transmit gain or a receive loss according to the measured loss at each input/output path of the MIMO antenna panel at the input for the common calibration receiver port.

The present disclosure relates to a radio astronomy interference signal reduction method, apparatus, and system and a computer device. The method includes: acquiring at least two beam signals, and obtaining a covariance matrix between all the beam signals according to the beam signals, wherein the beam signals include subsignals from at least two directions; performing eigen-decomposition processing on the covariance matrix to obtain signal eigenvectors and eigenvalues corresponding to the subsignals, and extracting interference eigenvectors corresponding to interference signals from the signal eigenvectors based on the eigenvalues; and obtaining a target reduction result for the interference signals according to the signal eigenvectors and the interference eigenvectors. With the method, the problem of low accuracy of radio astronomy interference signal reduction in the related art can be solved.

A calibration apparatus for calibrating a transceiver includes a loop back circuit, an estimation circuit, and a calibration circuit. The loop back circuit is coupled between a mixer output port of a transmitter (Tx) of the transceiver and a mixer input port of a receiver (Rx) of the transceiver, and applies a sequence of different loop gains. The estimation circuit receives a loop back receiving signal that is output from the Rx under the sequence of different loop gains, and generates at least one estimated value of impairment of the transceiver by performing channel estimation according to at least the loop back receiving signal. The calibration circuit performs calibration upon the transceiver according to the at least one estimated value.

The present disclosure relates to a test and/or measurement system. The test and/or measurement system comprises a base unit which comprises: an LO signal source configured to generate an LO signal, a first LO port and a second LO port, wherein the LO signal source is connected to the first LO port and the second LO port, and an LO measurement device. The test and/or measurement system further comprises: a first external frontend which is connected to the first LO port of the base unit via a first cable, and which is configured to receive a first fraction of the LO signal from the first LO port, wherein the first external frontend comprises one or more calibration standards; and a second external frontend which is connected to the second LO port of the base unit via a second cable, and which is configured to receive a second fraction of the LO signal from the second LO port, wherein the second external frontend comprises one or more calibration standards. The test and/or measurement system is operable in a calibration mode in which: the first external frontend is configured to connect the first LO port with one of its one or more calibration standards, the second external frontend is configured to connect the second LO port with one of its one or more calibration standards, and the LO measurement device is configured to measure: the LO signal which is generated by the LO signal source, a reflection of the first fraction of the LO signal received at the first LO port, and a reflection of the second fraction of the LO signal received at the second LO port.

The present disclosure relates to a radio astronomy interference signal reduction method, apparatus, and system and a computer device. The method includes: acquiring at least two beam signals, and obtaining a covariance matrix between all the beam signals according to the beam signals, wherein the beam signals include subsignals from at least two directions; performing eigen-decomposition processing on the covariance matrix to obtain signal eigenvectors and eigenvalues corresponding to the subsignals, and extracting interference eigenvectors corresponding to interference signals from the signal eigenvectors based on the eigenvalues; and obtaining a target reduction result for the interference signals according to the signal eigenvectors and the interference eigenvectors. With the method, the problem of low accuracy of radio astronomy interference signal reduction in the related art can be solved.

A calibration apparatus for a communication system. The calibration apparatus is configured to: a) set a variable termination-resistance at a receiver to a predetermined value; b) cause a transmitter to send a calibration pattern to the receiver by: setting the differential voltage on the line to a non-zero value during a non-zero-phase; and setting the differential voltage on the line to zero during a subsequent zero-phase; c) compare the differential voltage on the line during the zero-phase with a reduced-bit-value-threshold, wherein the reduced-bit-value-threshold is less than a bit-value-threshold that is used during active communication. If the differential voltage on the line during the zero-phase exceeds the reduced-bit-value-threshold, then the calibration apparatus adjusts the value of the variable termination-resistance and returns to step b). If the differential voltage on the line during the zero-phase does not exceed the reduced-bit-value-threshold, then the calibration apparatus stores the current value of the variable termination-resistance for subsequent use during active communication.

Certain aspects of the present disclosure provide techniques and apparatus for calibrating radio frequency (RF) circuits using machine learning. One example method generally includes calibrating a first subset of RF circuit calibration parameters. Values are predicted for a second subset of RF circuit calibration parameters based on a machine learning model and the first subset of RF circuit calibration parameters. The second subset of RF circuit calibration parameters may be distinct from the first subset of RF circuit calibration parameters. At least the first subset of RF circuit calibration parameters is verified, and after the verifying, at least the first subset of RF circuit calibration parameters are written to a memory associated with the RF circuit.

A chip-scale controller for a reconfigurable radio frequency (RF) filter may include memory configured to store a calibration profile associating each of a plurality of digital command inputs with a plurality of digital to analog converter (DAC) codes, a plurality of digital to analog converters (DACs) each configured to generate an analog biasing output in response to one of a DAC code, a communication interface configured to receive a digital command input, and control registers configured to retrieve, from the memory, at least one plurality of DAC codes based on the received digital command input, to select a plurality of DAC codes based on the retrieved at least one plurality of DAC codes, and to provide the selected plurality of DAC codes to the plurality of DACs. At least the plurality of DACs, the communication interface, and the control registers form part of an application specific integrated circuit.

A first wireless device and a second device may negotiate a configuration of an RF chain calibration process with each other. The configuration of the RF chain calibration process may include a number of calibration rounds. The second wireless device may exchange, in each calibration round in the number of calibration rounds, at least one RS and at least one feedback message with the first wireless device. The second wireless device may identify one or more calibration adjustment parameters for the second wireless device based on the RF chain calibration process. The second wireless device may communicate with another wireless device based on the one or more calibration adjustment parameters.

Methods, systems, and devices for receiver decision feedback equalization calibration are described. A memory system may support implementing respective decision feedback equalization (DFE) values at respective receivers using interpolation logic. For example, a calibration circuit may generate and store a quantity of candidate voltage values corresponding to the application of different DFE values at the receivers. The memory system may use the interpolation logic to generate (e.g., interpolate, generate) respective voltage values corresponding to a DFE value for application at a respective receiver based on the stored candidate voltage values. The interpolation logic may output the voltage values via a serial bus to each receiver, and each receiver may apply, to respectively received data, a DFE value corresponding to a respectively received voltage value.