(Gauss) frequency shift keying ((G)FSK) digital demodulation device and method

Abstract

The invention discloses a frequency shift keying (FSK) or a Gauss frequency shift keying (GFSK) digital demodulation device and method. The device comprises an FSK or GFSK demodulation circuit and a code element recovery circuit, wherein the FSK or GFSK demodulation circuit is used for detecting the intermediate frequency of a modulation signal so as to demodulate the modulation signal by adopting proper intermediate frequency, and outputting a demodulation result; and the code element recovery circuit is used for counting positions of a rising edge and a falling edge of the demodulated signal output by the FSK or GFSK demodulation circuit, searching for an initial position of a proper single code element and outputting an accurate code element. The FSK or GFSK digital demodulation device and the FSK or GFSK digital demodulation method have the advantages that: a bit error rate is low, and the parameter setting of a scheme is regulated according to different frequency shift tolerances so as to achieve simple structure and high flexibility; the code element can be effectively recovered and the offset of an external clock can be resisted; and only a digital circuit is adopted so as to achieve low cost.

Description

technical field [0001] The present invention relates to the communication field, in particular to a (Gauss) Frequency Shift Keying ((Gauss) Frequency Shift Keying, FSK or GFSK for short) digital demodulation device and method. Background technique [0002] At present, the common FSK or GFSK demodulation circuits are: the demodulation circuit using the analog differentiator, the power consumption is relatively large, and the tolerance to the frequency offset of the intermediate frequency is low; the demodulation circuit using the time domain differentiator requires a high-performance filter, which leads to relatively large power consumption; the demodulation circuit using zero-crossing detection and pulse shaping adopts a digital-analog hybrid method, and the power consumption is relatively low, but the circuit for anti-IF offset is relatively complicated; the phase-locked loop is used to realize FSK demodulation is complicated to implement; FSK demodulation using ADC (digita...

AI Technical Summary

Problems solved by technology

[0006] Another technical problem to be solved by the present invention is to provide a digital demodulation method to overcome the limitations of existing demodulation methods such as high power consumption, high complexity, high cost and tolerance to intermediate frequency offset and symbol recovery schemes. insufficient

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