An in-phase and quadrature mismatch compensator for a quadrature transmitter includes a delay element, a complex-valued filter and an adder. The delay element receives an input transmit signal and outputs a delayed transmit signal. The complex-valued filter receives the input transmit signal and outputs a selected part of a filtered output transmit signal. The adder adds the delayed transmit signal and the selected part of the filtered output transmit signal and outputs a pre-compensated transmit signal. In one embodiment, the selected part of the filtered output transmit signal includes the real part of the complex-valued output transmit signal. In another embodiment, the selected part of the filtered output transmit signal includes the imaginary part of the complex-valued output transmit signal. Two transmit real-valued compensators are also disclosed that combine the in-phase and quadrature signals before being filtered.

A microelectromechanical system (MEMS) gyroscope sensor has a sensing mass and a quadrature error compensation control loop for applying a force to the sensing mass to cancel quadrature error. To detect fault, the quadrature error compensation control loop is opened and an additional force is applied to produce a physical displacement of the sensing mass. A quadrature error resulting from the physical displacement of the sensing mass in response to the applied additional force is sensed. The sensed quadrature error is compared to an expected value corresponding to the applied additional force and a fault alert is generated if the comparison is not satisfied.

A Radio Frequency Impairments (RFI) compensator and a process to remove RFI is disclosed. The RFI compensator including: a conjugator to conjugate a signal {tilde over (x)}[n] to provide a signal {tilde over (x)}*[n]; and a filter to apply coefficients that equalize a linear distortion of the signal {tilde over (x)}[n] and reject an interfering image of the signal {tilde over (x)}*[n]. The signal {tilde over (x)}[n] maybe a single wideband carrier or may include multiple carriers at different carrier frequencies.

A method, network node and system for providing joint phase and delay compensation for a plurality of antenna branches in a network node having a plurality of antennas by processing injected signals and feedback signals in a frequency domain are provided. According to one aspect, a method includes performing at least squares algorithm applied to the injected signals and the feedback signals to generate corrective signals applied to input signals of each antenna branch.

The present disclosure describes techniques for efficiently handling QAM overflow while transmitting online services. The QAM overflow indicates an instance when summation of the set of transmission data rates corresponding to the set of services exceeds threshold data rate. The techniques of present disclosure comprises monitoring transmission of the set of services having a corresponding set of transmission data rates and a corresponding set of transmission priorities, each service comprising a first set of data packets and a second set of data packets. The techniques further comprises preventing the QAM overflow by blocking transmission of at least one of first set of data packets and second set of data packets of one or more services, amongst the set of services, from lowest to highest transmission priority till a summation of transmission data rates of remaining services continued to be transmitted is less than or equal to a threshold data rate.

To reduce signal distortion, a remote terminal receives a quadrature-modulated transmitter-check signal from a user terminal. The remote terminal measures an in-phase/quadrature (I/Q) imbalance error and/or a direct current (DC) offset error in the transmitter-check signal. The remote terminal then transmits to the user terminal transmitter-correction information derived from an I/Q imbalance error or a DC offset error. The transmitter-correction information is for counteracting the I/Q imbalance error or the DC offset error at the user terminal.

Embodiments provide a pre-distortion circuit and apparatus, a method and computer program for pre-distorting, a transmitter, a radio transceiver, a communication device, a mobile transceiver, a base station transceiver and a storage. The pre-distortion circuit (10) is configured for a digital quadrature signal. The pre-distortion circuit (10) comprises a first input (12) for an inphase component of the quadrature signal and a second input (14) for a quadrature component of the quadrature signal. The pre-distortion circuit 10 comprises a signal processing circuit (16) configured to determine whether polarities of the inphase component and quadrature component are equal, and to determine pre-distortion coefficients based on the amplitude of the inphase component, the amplitude of the quadrature component, and based on whether the polarities are equal.

A central challenge in next-generation 5G/6G networks is achieving high message reliability despite very dense usage and unavoidable signal fading at high frequencies. To provide enhanced fault detection, localization, and mitigation, the disclosed procedures can enable an AI model (or an algorithm derived from it) to discriminate between faulted and unfaulted message elements according to signal quality, modulation parameters, and other inputs. The AI model can estimate the likelihood that each message element is faulted, and predict the most probable corrected value, among other outputs. The AI model can also consider the quality of a demodulation reference used to demodulate the message, and the quality of the associated error-detection code. The AI model can also consider previously received messages to the same receiver, or messages of a similar type. Fault mitigation by the receiver can save substantial time and resources by avoiding a retransmission. Many other aspects are disclosed.

A wireless transceiver system includes a transmitter and a receiver. The transmitter includes a digital processor and a self-correction modulator coupled to the digital processor, wherein based upon a calibration correction assessment of an in-phase (I) signal and a quadrature (Q) signal received from the digital processor, the self-correction modulator generates a calibrated modulated signal. The self-correction modulator includes a core modulator and a calibration correction unit. The calibration correction unit is configured to correct an output of the core modulator based upon the calibration correction assessment. The calibration correction unit includes a calibration processing unit and a calibration modulator, wherein the calibration processing unit provides correction quantities that are used to program the calibration modulator to provide the self-corrected modulated signal.

A method of pre-compensating for transmitter in-phase (I) and quadrature (Q) mismatch (IQMM) may include sending a signal through an up-converter of a transmit path to provide an up-converted signal, determining the up-converted signal, determining one or more IQMM parameters for the transmit path based on the determined up-converted signal, and determining one or more pre-compensation parameters for the transmit path based on the one or more IQMM parameters for the transmit path. In some embodiments, the up-converted signal may be determined through a receive feedback path. In some embodiments, the up-converted signal may be determined through an envelope detector.