The disclosure relates to an IQ mismatch correction module for a radio receiver, the IQ mismatch correction module comprising: an input terminal configured to receive an input signal; an output terminal configured to provide a filtered output signal; a mismatch detection module comprising: one or more bandpass filters configured to receive, from the input terminal or output terminal, a bandpass input signal and to pass a plurality of sub-bands of the bandpass input signal to provide respective bandpass filtered signals; one or more amplitude and phase mismatch detectors configured to determine amplitude and phase mismatch coefficients based on the bandpass filtered signals from the plurality of sub-bands; a transformation unit configured to apply a transformation to the amplitude and phase mismatch coefficients to provide correction filter coefficients for the plurality of sub-bands; and a filter module configured to: receive the filter coefficients for the plurality of sub-bands from the mismatch detection module; and filter the input signal in accordance with the received filter coefficients to provide the filtered output signal.

An EVM measurement value is appropriately determined while CPE/ICI correction is taken into account. In a measurement apparatus (300), an EVM measurer (305) measures a modulation quality of a signal transmitted from a transmission apparatus. An EVM determiner (306) determines whether or not the measurement value of the modulation quality is equal to or less than a first requirement value, in a case where correction relating to a phase noise of the transmission apparatus is necessary in a reception apparatus. The first requirement value herein is higher than a second requirement value used in the determination of the measurement value in a case where the correction relating to the phase noise of the transmission apparatus is unnecessary in the reception apparatus.

A modulation format estimation device 100 includes: a frequency shift correction unit 112 configured to estimate the amount of a frequency shift using a baseband signal acquired from a received signal and correct the baseband signal based on an estimation result; a frequency error generation unit 122 configured to generate a plurality of frequency errors from a range set based on an error occurring in the estimation of the frequency shift amount; a frequency error introduction unit 123 configured to acquire learning baseband signals in which each of a plurality of source signals modulated by different modulation formats is frequency-shifted by each frequency error; and a modulation format estimation unit 113 configured to input a corrected baseband signal to a first machine learning model created by machine learning using learning data including the plurality of learning baseband signals and a label, and estimate a modulation format of the received signal.

A method of compensating for IQ mismatch (IQMM) in a transceiver may include sending first and second signals from a transmit path through a loopback path, using a phase shifter to introduce a phase shift in at least one of the first and second signals, to obtain first and second signals received by a receive path, using the first and second signals received by the receive path to obtain joint estimates of transmit and receive IQMM, at least in part, by estimating the phase shift, and compensating for IQMM using the estimates of IQMM. Using the first and second signals received by the receive path to obtain estimates of the IQMM may include processing the first and second signals received by the receive path as a function of one or more frequency-dependent IQMM parameters.

A faulted message element in 5G or 6G can often be identified according to its modulation parameters, including a large deviation of the branch amplitudes from the predetermined amplitude levels of the modulation scheme, and/or the SNR of the branch amplitudes, and/or an amplitude variation of the raw signal or the branches during the message element, and/or an inconsistency between the modulation state as determined by the amplitude and phase of the raw waveform versus the amplitudes of the orthogonal branch signals, among other measures of modulation quality. An AI model may be necessary to correlate the various quality measures, and optionally to determine the correct demodulation of faulted message elements. Costly, time-consuming retransmissions may be avoided by determining the correct demodulation of each message element at the receiver, thereby improving throughput and reliability with fewer delays.

A radio frequency (RF) communication assembly includes an RF communication circuit and a compensator apparatus. The compensator apparatus receives an input including an I-component of a pre-compensated signal, a Q-component of the pre-compensated signal, and encoded operating conditions of the RF communication circuit. The RF communication circuit includes RF circuit components causing signal impairments. The compensator apparatus perform neural network computing on the input, and the RF communication assembly generates a compensated output signal that compensates for at least a portion of the signal impairments.

The disclosure relates to technology for compensating for I/Q imbalance. An apparatus includes I-path circuitry having a first analog filter configured to filter an I-path signal and Q-path circuitry having a second analog filter configured to filter a Q-path signal. An I/Q imbalance compensation circuit of the apparatus is configured to process digital versions of the I-path signal and the Q-path signal to compensate for mismatch between the I-path circuitry and the Q-path circuitry. A first circuit of the apparatus is configured to apply a coarse adjustment to at least one of the first analog filter or the second analog filter to reduce an initial mismatch between the I-path circuitry and the Q-path circuitry. The first circuit is configured to operate the I/Q imbalance compensation circuit to compensate for a residual mismatch between the I-path circuitry and the Q-path circuitry with the coarse adjustment applied.

A millimeter-wave phase array system may include massive heterodyne transceivers as its building elements. A transceiver of each element may include an IQ image rejection heterodyne transmitter and a receiver. Each transmitter may include a single DAC, a Tx I channel, and a Tx Q channel. Each receiver may include an Rx I channel, an Rx Q channel, and a single ADC. For Tx IQ image rejection calibration, amplitude and phase offsets are determined, using both the Tx I and Tx Q channels from a first element and using only one of the Rx I or Rx Q channel from a second element. The IQ channel imbalances are compensated using the offsets in analog domain. A similar procedure is used for Rx IQ image rejection calibration with alternated signal path enabling. A frequency response variation of an RF front end is detected with a single path Tx/Rx channel setup.

A self-diagnosis device of a radar system or a phased-array antenna module including a general-purpose multi-channel IC and a transmission phase shifter IC having a plurality of transmission output terminals and reception terminals is configured to perform a self-diagnosis of the transmission phase shifter by utilizing a signal that is generatable by the general-purpose multi-channel IC, which is enabled by a built-in self-test circuit that (A) generates a self-diagnosis monitor signal converted into a low frequency band, which is a mixture of (i) a self-diagnosis signal generated from (a) a third output signal and a fourth output signal output in sync from same PLL with (b) a first output signal to be supplied to a reception frequency converter of the general-purpose multi-channel IC, and (ii) a composite signal of the transmission channel, and (B) analyzes a phase of the self-diagnosis monitor signal.

In one embodiment, an apparatus includes a baseband circuit to generate a plurality of subcarriers of a complex sample of a message to be transmitted, and a compensation circuit coupled to the baseband circuit, the compensation circuit to compensate for IQ mismatch. The compensation circuit may include: a calibration circuit to determine, using a tone signal, gain correction values and phase correction values for a subset of the plurality of subcarriers; and a correction circuit to apply the gain correction values and the phase correction values to the plurality of subcarriers to compensate for the IQ mismatch.