Realtek Semiconductor Inc.

Hong-Ta Hsu

Ying-Hsi Lin

Yuan-Shuo Chang

Chin Su

An adjusting method for reducing local oscillation leakage or I/Q mismatch in a transmitter includes the steps of: (a) detecting a current extent of local oscillation leakage or I/Q mismatch; (b) determining if an adjusting direction is correct with reference to the current extent of local oscillation leakage or I/Q mismatch thus detected, maintaining the adjusting direction if correct, and reversing the adjusting direction upon determining that the adjusting direction is incorrect; and (c) adjusting a control signal according to the adjusting direction.

Transmitter capable of reducing local oscillation leakage and in-phase/quadrature-phase (I/Q) mismatch and adjusting methods thereof

A method for estimating a sampling delay error between a first analog-to-digital converter (ADC) and a second ADC in a time-interleaved ADC includes: receiving a first digital output signal and a second digital output signal generated from the first ADC and the second ADC based on a same analog input signal, respectively; determining a delay amount according to a predetermined sampling delay between the first ADC and the second ADC and a delay adjusting value, and applying the delay amount delay to the second digital output signal to generate a delayed digital output signal, wherein the delay adjusting value Td is used to estimate the sampling delay error Te; calculating a difference between the first digital output signal and the delayed digital output signal; and feeding back the difference for adjusting the delay adjusting value Td according to the difference.

Method and apparatus for estimating sampling delay error between first and second analog-to-digital converters of time-interleaved analog-to-digital converter

A method for compensating mismatches of an in-phase signal and a quadrature signal of a transmitter/receiver is provided. The method includes: receiving a plurality of test signals to generate two groups of factors, respectively, where each group of factors is applied to two multipliers utilized for compensating a gain mismatch and a phase mismatch of the in-phase signal and the quadrature signal of the transmitter/receiver; then calculating a delay mismatch of the in-phase signal and the quadrature signal according to the two groups of factors.

Method for compensating mismatch of in-phase signal and quadrature signal of transmitter/receiver

A method and apparatus of calibrating I/Q mismatch of a communication circuit is disclosed. The disclosure employs I/Q test signals respectively including different frequency components to calibrate the frequency-dependent I/Q mismatch existing in the communication system.

Methods and apparatuses of calibrating I/Q mismatch in communication circuit

A receiver having a mixer for mixing a radio frequency signal and a local oscillator signal so as to generate a base band signal, a detecting unit for generating from the base band signal a detection signal that represents an extent of local oscillation leakage, and an adjusting unit coupled electrically to said mixer for outputting a control signal thereto to control a current operating state of said mixer, said adjusting unit being further coupled electrically to said detecting unit, and determining whether there is a reduction in the extent of local oscillation leakage based on the detection signal from said detecting unit. In operation, the adjusting unit maintains an adjusting direction for the control signal upon determining that the extent of local oscillation leakage is reduced, reverses the adjusting direction upon determining that the extent of local oscillation leakage is not reduced, and adjusts the control signal according to the adjusting direction.

Receiver capable of reducing local oscillation leakage and in-phase/quadrature-phase (I/Q) mismatch and an adjusting method thereof

A receiver for compensating I/Q mismatch includes an analog down-conversion unit for receiving a radio frequency signal and down-converting the RF signal into a set of digital low intermediate frequency (IF) signals, a digital down-conversion unit receiving the set of digital low IF signals and down-converting the set of digital low IF signals into first and second baseband signals, and a compensation unit. The compensation unit receives the first and second baseband signals, calculates a compensation parameter based thereon, and compensates I/Q mismatch effect according to the first and second baseband signals and the compensation parameter so as to output a target signal.

Receiver for compensating I/Q mismatch, compensation device, compensation module and compensation parameter calculating module

An adjusting method for reducing local oscillation leakage or I/Q mismatch in a receiver includes the steps of: (a) detecting a current extent of local oscillation leakage or I/Q mismatch; (b) determining if an adjusting direction is correct with reference to the current extent of local oscillation leakage or I/Q mismatch thus detected, maintaining the adjusting direction if correct, and reversing the adjusting direction upon determining that the adjusting direction is incorrect; and (c) adjusting a control signal according to the adjusting direction.

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Hsinchu, Taiwan

Hong-Ta Hsu