Realtek Semiconductor Inc.

Proscend Communications Inc.

Yuan-Shuo Chang

Wen-Shan Wang

Tzu-Ming Kao

Wu-Chi Wang

Chin-Liang Wang

Ching-Chia Cheng

Ying-Hsi Lin

Hong-Ta Hsu

Tzu Ming Kao

Shin-Lin Cheng

Min-Chau Jan

Chien-Yu Chen

Chih-Wei Lai

Yi-Chang Shih

Ming-Chung Huang

Chih-Chieh Wang

Kuan-Kai Chen

A communications device and a method for compensating frequency response distortion of the communication device are provided. The communications device includes a transmitting path circuitry, a receiving path circuitry, a memory pre-distortion circuit, a pre-equalizer circuit and a pre-equalization calculation circuit. The transmitting path circuitry and the receiving path circuitry are configured to generate a feedback signal according to a pre-distortion test signal, where a set of pre-distortion coefficients of the memory pre-distortion circuit are calibrated according to the feedback signal. After calibration of the set of pre-distortion coefficients is finished, the pre-equalization calculating circuit performs calculation on the set of pre-distortion coefficients to generate a calculation result for calibrating the pre-equalizer circuit. After calibration of the pre-equalizer circuit is finished, a transmission signal is processed by the pre-equalizer circuit and the memory pre-distortion circuit first, and then output to outside of the communications device via the transmitting path circuitry.

Communications device and method for compensating frequency response distortion of communications device

A communications device and a method for compensating frequency response distortion of the communications device are provided. The communications device includes a transmitting path circuitry, a receiving path circuitry, a pre-distortion circuit and a pre-equalizer circuit. The transmitting path circuitry generates an output test signal according to a pre-distortion test signal, and the receiving path circuitry generates a first feedback signal according to the output test signal, where the pre-distortion circuit is calibrated according to the first feedback signal. After calibration of the pre-distortion circuit is finished, the pre-distortion circuit generates a second feedback signal according to a single tone signal, where the pre-equalizer circuit is calibrated according to the second feedback signal. After calibration of the pre-equalizer circuit is finished, a transmission signal is processed by the pre-equalizer circuit and the pre-distortion circuit first and then output via the transmitting path circuitry to outside the communications device.

A method for calibrating compensation values utilized by a compensation device in a transmitter includes: obtaining a plurality of output signals sequentially generated by the transmitter by processing a pair of input signals based on a plurality of pairs of compensation values as a plurality of feedback signals, where each feedback signal corresponds to one of the plurality of pairs of compensation values; obtaining a signal component of the feedback signals at a predetermined frequency as a portion of the feedback signals; determining a pair of equivalent impairment parameters in a calibration operation according to the plurality of pairs of compensation values and the portion of the feedback signals; and determining a pair of calibrated compensation values according to the pair of equivalent impairment parameters and providing the pair of calibrated compensation values to the compensation device.

Transmitter circuit, compensation value calibration device and method for calibrating compensation values

A method and circuit for controlling the compensation for channel mismatches are used in an electronic device which includes a signal transmission circuit or a signal receiving circuit that have two channels. The electronic device further includes a channel mismatch compensation circuit. The method includes: (A) determining a frequency of a test signal; (B) causing the test signal to pass through the signal transmission circuit or the signal receiving circuit, and measuring an image signal; (C) adjusting a compensation parameter of the channel mismatch compensation circuit to change an amplitude of the image signal; (D) determining, according to the amplitude of the image signal, a target compensation parameter of the channel mismatch compensation circuit, the target compensation parameter corresponding to the frequency of the test signal; (E) repeating steps (A) to (D) to obtain multiple target compensation parameters; and (F) determining a compensation mechanism based on the target compensation parameters.

Method and circuit for controlling channel mismatch compensation

The present application provides a method for calibrating a transmitter. The transmitter includes an oscillator, a first signal path, and a second signal path. The first signal path and the second signal path include a first calibration unit preceding a first low pass filter and a second low pass filter, and a second calibration unit succeeding the first low pass filter and the second low pass filter. The calibration method includes: by configuring the first calibration unit and the second calibration unit and sending a transmission signal, and performing frequency analysis upon the transmission signal to obtain a frequency analysis result, to generate an optimized first compensation value for the first calibration unit and an optimized second compensation value for the second calibration unit.

Method for calibrating transmitter

A communication system is provided, which includes a power amplifier, a receive-end filter, an ADC, an output simulation circuit, and a predistortion circuit. The power amplifier amplifies a RF input signal to generate a RF output signal. The RF input signal is generated according to a baseband signal. The receive-end filter filters a feedback signal generated according to the RF output signal to output a filtered feedback signal. A bandwidth of the filtered feedback signal is at least 3 to 5 times a bandwidth of the RF input signal. The ADC converts the filtered feedback signal to a digital input signal. The output simulation circuit generates, according to the digital input signal and the baseband signal, a reference signal simulating the RF output signal. The predistortion circuit builds a predistortion model according to the reference signal.

Communication system and output power linearization method thereof

A signal compensation device comprises a first filter circuit, for processing a broadband signal, to generate a first analog time-domain signal; a second filter circuit, for processing the broadband signal, to generate a second analog time-domain signal; a first transform circuit, for transforming the first analog time-domain signal to a first digital time-domain signal; a second transform circuit, for transforming the second analog time-domain signal to a second digital time-domain signal; a third transform circuit, for transforming the first digital time-domain signal to a first frequency-domain signal; a fourth transform circuit, for transforming the second digital time-domain signal to a second frequency-domain signal; and a processing circuit, for generating a time-domain compensation response according to the first frequency-domain signal and the second frequency-domain signal.

Device and method of performing signal compensation

A transmitter device includes a transmitter including a first oscillator circuitry, a signal processing circuitry, and a calibration circuitry, and a second oscillator circuitry. The first oscillator circuitry is configured to output a first oscillating signal. The signal processing circuitry is configured to mix calibration signals according to the first oscillating signal, in order to emit a first output signal. The calibration circuitry is configured to detect a power of the first output signal to generate coefficients, and generate the calibration signals according to the coefficients, an in-phase data signal, and a quadrature data signal. The second oscillator circuitry is disposed adjacent to the transmitter, and is configured to output a second oscillating signal. The calibration signals are configured to reduce a pulling generated by both of the first output signal and the second oscillating signal to the first oscillator circuitry.

Signal transmitter device and calibration method

The application discloses a transceiver and a transceiver calibration method. The transceiver includes: a calibration signal generation unit for generating a first test signal and a second test signal to a transmission unit in a gain calibration mode; the transmission unit for generating a combined signal according to the first test signal, the second test signal and a transmission gain; a mixer for performing self-mixing upon the combined signal to generate a self-mixed signal; a receiving unit for generating a receiving signal according to the self-mixed signal; a Fourier transformer for computing a power of the receiving signal at a specific frequency; and a gain calibration unit for adjusting the transmission gain according to the power at the specific frequency in the gain calibration mode.

Transceiver and transceiver calibration method

An apparatus for use in a polar transmitter to perform distortion estimation and compensation is provided. The apparatus includes a mixing unit, a signal processing unit, an estimation unit and a compensation unit. The mixing unit is configured to mix a test output signal and a frequency down-converting signal to generate a mixed signal. The processing unit is configured to perform signal processing on the mixed signal to generate a processed signal. The estimation unit is configured to perform distortion estimation on the processed signal to generate a distortion estimation result. The compensation unit is configured to perform pre-distortion compensation on input signals of the polar transmitter according to the distortion estimation result.

Method and apparatus for use in polar transmitter to perform nonlinear distortion estimation and compensation

A method for characterizing nonlinear distortion of a transmitter, an associated transmitter and a characterization circuit thereof are provided. The method includes: utilizing a transmitting chain circuit within the transmitter to generate an output signal according to a test signal; utilizing a loop back circuit within the transmitter to generate a loop back signal according to the output signal; calculating a plurality of distorted indices respectively corresponding to a plurality of test samples of the test signal according to a plurality of loop back samples of the loop back signal, wherein the plurality of test samples correspond to the plurality of loop back samples, respectively; dividing the plurality of distortion indices into multiple groups according to power of the plurality of test samples; calculating an average value of distortion indices within each group of the multiple groups; and characterizing the nonlinear distortion of the transmitter according to the average value.

Method for characterizing nonlinear distortion of transmitter, associated transmitter and characterization circuit thereof

A receiver circuit of a transceiver is disclosed including: a calibration circuit arranged to operably perform an I/Q mismatch calibration operation according to an in-phase detection signal and a quadrature detection signal to generate one or more compensation parameters; a parameter storage circuit; an interference detection circuit arranged to operably generate an estimated signal-to-interference ratio according to the in-phase detection signal and the quadrature detection signal; a receiver control circuit arranged to operably determine whether to discard the one or more compensation parameters, wherein the receiver control circuit stores the one or more compensation parameters into the parameter storage circuit only if the estimated signal-to-interference ratio exceeds a predetermined threshold.

Receiver circuit for determining whether to discard I/Q mismatch compensation parameters according to signal-to-interference ratio

A signal transmitter device includes a transmitter and a detection circuit. The transmitter is configured to transmit an output signal based on a first baseband signal and a second baseband signal, in which the first baseband signal and the second baseband signal have a baseband frequency. The detection circuit is configured to perform twice signal modulations according to the output signal to detect a signal component, which has the baseband frequency, of the output signal, in order to control a compensation circuit to correct a channel mismatch of the transmitter.

Signal transmitter device, detection circuit, and signal detection method thereof

A transmitter circuit includes: an in-phase signal processing circuit; a quadrature signal processing circuit; an analog signal processing circuit arranged to operably generate a corresponding analog signal according to the signals outputted from the in-phase signal processing circuit and the quadrature signal processing circuit; a transmitter control circuit arranged to operably control the in-phase signal processing circuit and the quadrature signal processing circuit to cooperate with the analog signal processing circuit to generate a first predetermined signal at a first time point, and to operably control the in-phase signal processing circuit and the quadrature signal processing circuit to cooperate with the analog signal processing circuit to generate a second predetermined signal at a second time point, and an image rejection ratio measurement circuit arranged to operably generate an estimated image rejection ratio of the transmitter circuit.

Transmitter circuit capable of measuring transmitter-side image rejection ratio

A transmitter with compensating mechanism of pulling effect includes an output unit and a correction unit. The output unit mixes a first correction signal and a second correction signal according to an oscillating signal to generate a modulated signal, and to amplify the modulated signal to generate a first output signal. The correction unit analyzes the power of the first output signal to generate a first coefficient and a second coefficient, and generate the first correction signal and the second correction signal according to the first coefficient, the second coefficient, an in-phase data signal, and a quadrature data signal.

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Hsinchu, Taiwan

Yuan-Shuo Chang