Method for fast phase shift keying demodulation under high/intermediate frequency under-sampling condition

Abstract

The invention discloses a method for fast phase shift keying demodulation under a high / intermediate frequency under-sampling condition. The method comprises the following steps of: performing matching design on the frequency of a high / intermediate frequency signal output by an analogue receiver and the sampling frequency of a sampling system, performing under-sampling on the high / intermediate frequency signal, sequentially performing broadband extraction and narrowband extraction on the high / intermediate frequency signal to obtain high-accuracy phase resolution, and performing phase modulation and demodulation. A high / intermediate frequency design is adopted, so that consistence with the condition of limitation of a sampling rate on software-defined radio is not required, the adoption of two paths of local oscillators is not required, the problem of amplitude and phase inconsistence caused by analogue mixing is not required to be taken into account, broadband signal analysis can be combined, an algorithm design with complex numbers is also not required to be taken into account, and the method has high signal adaptability.

Description

technical field [0001] The invention belongs to the field of signal processing, and in particular relates to a phase encoding fast demodulation method under the condition of high and medium frequency undersampling. Background technique [0002] In order to ensure the rational and orderly use of various spectrum resources, the radio signal management system must have the ability to detect, analyze and identify various modulated signals. As one of the important methods of radio spread spectrum technology, phase modulation has been widely used in various In such radio signals, whether the internal phase modulation and coding laws of pulse signals can be analyzed quickly and in real time will affect the supervision efficiency of the radio management system. At present, the domestic non-cooperative radiated signal modulation and demodulation schemes mainly include: [0003] Scheme 1. The two-way signals output by the power divider and the local oscillator using the quadrature ph...

AI Technical Summary

Problems solved by technology

However, it is still necessary to design a complex filter to filter the signal, which increases the amount of calculation

Although the third solution is full digital processing, it does not realize down-conversion, and it is more difficult for engineering application

Therefore, if there is no further optimized design scheme and algorithm, it is difficult to ensure the real-time performance of the system for the demodulation of the non-cooperative target phase code, and the engineering application value of the electronic countermeasure reconnaissance system will be greatly limited.

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