Super-high-dynamic spread spectrum signal fast-capturing method suitable for reusable orbiter

Abstract

The invention relates to a super-high-dynamic spread spectrum signal fast-capturing method suitable for a reusable orbiter. The method comprises the steps that fast-capturing parameters of spread spectrum signals are calculated at first, then multiple channels of pseudo codes based on masks are generated, and fast capturing of the spread spectrum signals is achieved by conducting FFT analysis by turns at last. The specific steps are that a carrier frequency is divided into subsections, and signal capturing is conducted in each frequency subsection; multiple channels of parallel pseudo codes are generated in a mask mode, partial correlation operation is conducted on each channel of pseudo codes and input signals, and FFT conversion is conducted on multi-channel parallel correlation operation results by turns to save resources; after all frequency bands are traversed, precise values of carrier Doppler and pseudo code phases are obtained. The super-high-dynamic spread spectrum signal fast-capturing method suitable for the reusable orbiter effectively solves the spread spectrum signal fast-capturing problem of the reusable orbiter, and achieves fast capturing of the spread spectrum signals with the huge Doppler frequency offset and the dynamic range.

Description

technical field [0001] The invention belongs to the technical field of measurement and control communication, and relates to a method for quickly capturing extremely high dynamic spread spectrum signals suitable for reusable orbital vehicles. Background technique [0002] The measurement and control terminal is the core equipment of the measurement and control communication system of the reusable orbiter, and it works with the ground station to complete the measurement and control task of the aircraft. [0003] The blackout phenomenon will occur for a long time when the orbiter is repeatedly used for hypersonic reentry flight. In order to improve the communication capability of the wireless signal blackout area, the Ka frequency band is used as the carrier frequency of the spread spectrum signal. Due to the high dynamic between the aircraft and the ground station, the received signal has a Doppler frequency shift, which has a bad effect on the capture of the spread spectrum ...

AI Technical Summary

Problems solved by technology

For the acquisition technology combining partial correlation and FFT, since the Doppler frequency range is as high as ±820kHz, higher requirements are placed on the Doppler frequency fading compensation performance of FFT. If the frequency compensation performance in the full frequency band is satisfied, some Closing the length first will reduce the capture sensitivity. If the capture sensitivity is guaranteed, the full frequency search of ±820kHz cannot be realized

For the matched filter capture method, although the capture speed is fast, the filter resource occupancy rate is extremely high. Even if the design method of filter folding is adopted, the resources of commonly used aircraft components (XQ2V3000) are difficult to bear, and due to the Doppler The frequency range is extremely wide, and the required frequency search channels will also increase significantly, and the time advantage brought by matched filtering is not obvious

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