Hypersonic aircraft large dynamic Doppler rapid capture method and communication system

Abstract

The invention belongs to the technical field of wireless communication, and discloses a hypersonic flight vehicle large dynamic Doppler rapid capture method and a communication system, and the methodcomprises the steps: employing a blind rapid estimation algorithm to carry out the rapid estimation of the Doppler rate of a received signal; compensating the received signal by using the estimated Doppler rate, performing Fourier transform on the compensated received signal on a plurality of continuous symbols, and then performing square cumulative average on Fourier transform results of the plurality of symbols; and finally, carrying out peak value search on the accumulation result, wherein the maximum peak value is the captured Doppler frequency offset value, and the Doppler rate of the received signal is obtained through a blind estimation algorithm. The Doppler search range correction link based on flight condition estimation limits spectral peak search within a smaller range so as tofurther improve the capture precision and capture speed of carrier signals. According to the invention, the carrier signal capture probability and capture speed are improved, and the method can be applied to rapid / real-time measurement and control communication of hypersonic aircrafts.

Description

technical field [0001] The invention belongs to the technical field of wireless communication, and in particular relates to a large dynamic Doppler rapid acquisition method and a communication system of a hypersonic aircraft. Background technique [0002] During the maneuvering flight of a hypersonic vehicle, the measurement and control communication carrier signal will experience the influence of large dynamic Doppler, and because the signal-to-noise ratio of the signal received by the ground measurement and control station is low, it is difficult to analyze the carrier signal under the condition of low signal-to-noise ratio and large dynamic Doppler. fast and precise capture. [0003] At present, the closest existing technology: foreign scholar Falletti E proposes a Doppler frequency estimation method that is more accurate than the two-dimensional search algorithm by using the cross ambiguity function based on the traditional two-dimensional search algorithm of carrier fre...

AI Technical Summary

Problems solved by technology

[0006] To sum up, the problem existing in the existing technology is: under the conditions of low signal-to-noise ratio and large dynamic Doppler, there will be conflicts between the acquisition speed and the acquisition accuracy, which will lead to the inability to realize the fast and accurate acquisition of the carrier signal. capture

However, large dynamic Doppler will cause the signal energy to spread in the frequency domain, seriously affecting the energy accumulation of the signal

In addition, the dynamic nature of Doppler makes it difficult to compensate for Doppler shift in real time

There is a serious contradiction between the large dynamic Doppler acquisition accuracy and the acquisition speed due to the aforementioned two constraints

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