Method and device for digital front-end filtering

Abstract

The invention relates to a method and a device for digital front-end filtering. The method comprises the following steps: firstly, an analog base-frequency signal is introduced into an analog-digital conversion component by an input pin; after up-sampling is carried out on the analog base-frequency signal, the analog base-frequency signal is converted into sampling signals I and Q for output; the sampling signals I and Q enter a control unit via a data wire and are respectively output to a digital filter I and a digital filter Q; digital filtering is respectively carried out on the entering digital signals I1 and Q1, and digital signals I2 and Q2 after filtering are obtained; and one-time down-sampling is carried out on the digital signals I2 and Q2, and data obtained by sampling are output under the matching of a new sampling clock according to a new data rate. The method has the advantages that the waveform further approaches to an analog value, and the superimposition and the distortion of the frequency spectrum are avoided. A programmable component is adopted to realize the method for digital front-end filtering, and the design is flexible. The digital filters only use an adder and a shift register, thereby enhancing the efficiency of the whole digital front end and lowering the cost of the system.

Description

technical field [0001] The invention relates to a digital filtering method and its realization, in particular to a digital front-end filtering method used in a digital communication system receiver and its realization device. Background technique [0002] Communication systems are often subject to various noises and interferences, such as white noise and fluctuating noise. In the analog communication system, people often use the analog filter method to filter out most of the out-of-band noise of the signal, so as to improve the signal-to-noise ratio of the receiving system and facilitate the reception of the receiver. In the prior art IEEE802.15.4-2006 standard receiving system, the radio frequency signal entering the system becomes an analog baseband signal after being demodulated and down-converted. The analog baseband signal is subjected to analog-to-digital conversion after an analog low-pass filter to become a digital signal that can be processed by a baseband digital ...

AI Technical Summary

Problems solved by technology

However, due to the limited filtering accuracy of analog filters and the inconvenient adjustment, the filtering effect is often limited

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