Zero intermediate frequency receiver and correction method of zero intermediate frequency receiver

Abstract

The invention provides a zero intermediate frequency receiver and a correction method thereof. The zero intermediate frequency receiver comprises a first passive mixer and a second passive mixer; a first error correction circuit which is connected with the first passive mixer; a first trans-impedance amplifier which is connected with the first error correction circuit; a second error correction circuit which is connected with the second passive mixer; a second trans-impedance amplifier which is connected with the second error correction circuit, wherein each of the first error correction circuit and the second error correction circuit comprises a common-gate impedance conversion circuit; a DAC circuit which is connected with the output end of the common-gate impedance conversion circuit; a feedback circuit which is connected with the common-gate impedance conversion circuit, wherein the common-gate impedance conversion circuit is used for improving the impedance from each trans-impedance amplifier to the corresponding passive mixer; the DAC circuit is used for eliminating residual DC errors in the circuit; and the feedback circuit is used for absorbing the common-mode current generated by the DAC circuit.

Description

technical field [0001] The invention relates to the technical field of communications, in particular to a zero-IF receiver and a calibration method for the zero-IF receiver. Background technique [0002] In recent years, the development of advanced technology has provided greater freedom and development space for mixed-signal chip design; among them, fully integrated RF transceiver solutions including various correction algorithms have become a trend. The direct down-conversion (zero-IF) structure is an ideal choice due to its simple structure, low cost and low power consumption, but the quadrature error and DC error of the I and Q channels are the main non-ideal factors of the zero-IF architecture. is the main obstacle limiting its application. There are two main sources of DC error in a zero-IF receiver: static DC error due to device mismatch in the receive channel, and dynamic DC error due to LO leakage back to the mixer. Among them, the magnitude of the static DC error...

AI Technical Summary

Problems solved by technology

When the duty cycle of the signal and the threshold voltage of the switch work together, the switches of the mixer may be turned on at the same time, and the input of the op amp is shorted, causing the DC and noise of the output of the transimpedance amplifier to increase, thereby increasing the DC error and noise

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