DC offset correction method and device of zero intermediate frequency receiver

Abstract

The invention relates to a DC offset correction method of a zero intermediate frequency receiver. The method comprises the following steps that during an electrification initializing period of a receiver, a successive approximation algorithm digital processing module completes DC offset detection and stores detected DC offset values of I and Q components in a correction result storage unit; and every time the receiver carries out reception, the receiver automatically takes the DC offset values from the correction result storage unit, the DC offset values are converted into analog voltage signal via a DAC, the analog voltage signals are back fed to the input end of an analog amplifier, and DC offset correction is completed. A DC offset correction device of the zero intermediate frequency receiver comprises an analog amplifier, an analog converter, the successive approximation algorithm digital processing module, a switch K, a digital to analog converter (DAC) and the correction result storage unit connected sequentially; and the correction result storage unit is connected with the digital to analog converter. According to the invention, primary DC offset amount of the receiver is detected and stored in one step in the chip electrification initializing process of the receiver, and every time the receiver carries out reception, the stored DC offset values are loaded automatically, and are corrected before being input to the amplifier and the DAC.

Description

technical field [0001] The invention belongs to the field of communication, and in particular relates to a method and device for correcting DC offset in a zero-IF radio frequency receiver. Background technique [0002] The zero-IF receiver technology is relative to the traditional two-time frequency conversion technology, which only uses one frequency conversion. The air signal passes through the antenna, low-noise amplifier, and a mixer to directly down-convert the in-band RF signal into a baseband analog IQ signal, and then convert it into a digital IQ signal through an ADC, and then perform baseband processing such as demodulation and decoding; zero intermediate frequency The receiver has the characteristics of small size, low cost and easy monolithic integration. It has become a very competitive structure in the radio frequency receiver and is widely used in the field of wireless communication. [0003] However, the DC drift signal is the main defect of the zero-IF stru...

AI Technical Summary

Problems solved by technology

[0009] In view of the above-mentioned technical deficiencies, the present invention proposes a method and device for closed-loop DC correction, the purpose of which is to provide a DC offset calibration solution to solve the problem of amplifier and ADC dynamic range loss in the prior art

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