Non-coherent frequency compensation and modulation method and demodulating apparatus

Abstract

The invention proposes an incoherent frequency compensation and demodulation method and a demodulation device which have low power consumption, high performance and use the pseudo-randomness of the received signal phase and the PN code to realize the wireless digital communication data demodulation which has short distance, low power consumption and low packet loss rate through the carrier frequency error compensation and data recovery; the demodulation device is composed of a digital low-converter, a channel filter, a phase arithmetic unit, a phase differentiator, a frequency compensator and a PN code de-spreading correlator; the intermediate signal is converted into the plural baseband signals which are processed with channel outer band noise filtration so that the amplitude-time signal is converted into the phase-time signal; the phase differentiator is adopted to differentiate the phase-time signal; the frequency compensation circuit compensate the carrier frequency according to the phase difference signal and the phase average signal; the carrier frequency and the phase recovery circuit are avoided; the PN code correlator group processes the matching demodulation towards the semi-cosine shaping OQPSK and MSK signals of the DSSS directly to recover the baseband data; the incoherent frequency compensation and demodulation method and the demodulation device has the advantages of simple circuit, less quantity of hardware, easy low power consumption integration, good demodulation performance and being applicable to the wireless satellite navigation and the short-range wireless communication device with batteries as the power supply.

Description

technical field

[0001] The invention belongs to the technical field of wireless communication, and relates to a low-power-consumption high-performance non-coherent demodulation method suitable for half-cosine shaping OQPSK or MSK modulation method and Direct Sequence Spread Spectrum (DSSS), in particular to non-coherent frequency compensation and demodulation Tuning method and demodulation device. Background technique

[0002] At present, due to the narrow signal bandwidth and good demodulation performance of the half-cosine shaped OQPSK and MSK signals, they are widely used in the field of wireless digital communication.

[0003] There are two traditional half-cosine shaping OQPSK and MSK demodulation methods: one is to use a coherent demodulator, such as figure 1 shown. In the demodulation method, the out-of-band noise is filtered out through the band-pass filter 101, and then the synchronization and recovery of the carrier and phase are realized through the phase-locked...

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