Low-consumption digital decimation filter bank with variable decimation multiples and digital decimation and filtering method

Abstract

The invention discloses a low-consumption digital decimation filter bank with variable decimation multiples and a digital decimation and filtering method. The low-consumption digital decimation filter bank and the digital decimation and filtering method are used for the filtering and the decimation of data. The filter bank comprises a first stage, a second stage and a third stage, wherein the first stage is a cascading comb-shaped integrating filter which is used for achieving the decimation movement with large multiples, the second stage is a half-band filter of at least one stage which is used for achieving the decimation movement of the second stage, the third stage is a compensating filter which is used for compensating pass band damping and carrying out filtering decimation movement, and the first stage is the cascading comb-shaped integrating filter with variable decimation multiples in a non-recursion mode. The method comprises the steps of determining decimation ratios and the system structure of the decimation filter bank, decomposing the transfer function of the cascading comb-shaped integrating filter, selecting the decimation ratios meeting requirements to for combination and carrying out multi-phase decomposition on the cascading comb-shaped integrating filter, the half-band filter and the compensating filter. The low-consumption digital decimation filter bank with the variable decimation multiples and the digital decimation and filtering method have the advantages that the number of registers working close to high frequency can be reduced, resource consumption is reduced, and power dissipation is reduced.

Description

technical field [0001] The invention relates to a low-consumption digital decimation filter bank capable of decimate multiples, and also relates to a digital decimation filtering method. technical background [0002] In the field of analog-to-digital converter (ADC), the Sigma-delta ADC using oversampling technology has been widely used due to its advantages of high conversion precision and easy implementation. Sigma-delta ADC includes two parts of analog and digital, the analog part is composed of sigma-delta modulator, and the digital part is composed of digital decimation filter. The Sigma-delta modulator is based on oversampling and noise shaping technology to achieve signal modulation. It can transfer the noise to the high frequency band far away from the signal bandwidth under the premise of retaining the signal, so as to achieve the signal and noise in the frequency domain. Separation, at this time the signal output by the Sigma-delta modulator includes low-frequency...

AI Technical Summary

Problems solved by technology

[0023] Most of the existing half-band filters are placed in the last stage of decimation filtering, resulting in large attenuation and noise aliasing near the edge of the output frequency band, resulting in signal distortion at the edge of the output frequency band

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