Generation and capture system of encrypted frame hopping spread spectrum signal of air fleet link

Abstract

The invention relates to a generation and capture system of an encrypted frame hopping spread spectrum signal of an air fleet link, belonging to the technical field of aeronautical data link and radio navigation. The invention discloses a system framework of an encrypted frame hopping spread spectrum signal generation and capture method which can be implemented on a digital signal processor (DSP)and a FPGA (field programmable gate array) of a circuit board, and provides a baseband signal generation algorithm of an encrypted frame hopping spread spectrum system to replace a traditional long periodic sequence spread spectrum code and a compound pseudo code by absorbing the advantages of the easy capture of the compound pseudo code and the difficult breaking of the long periodic sequence spread spectrum code; and meanwhile, the invention provides two advanced and high-performance encrypted frame hopping spread spectrum signal capture algorithms, i.e. a frequency domain parallel capture method of the encrypted frame hopping spread spectrum signal of based on a FFT (fast fourier transform algorithm) and a direct capture method of the encrypted frame hopping spread spectrum signal based on a matching filter and the FFT. The invention solves the problem of difficult capture of the traditional long periodic sequence spread spectrum code. The method can be widely applied to satellite navigation receivers, range measurement systems and communication systems based on a quiescent carrier modulation direct sequence spread spectrum system.

Description

technical field [0001] The invention relates to an encrypted code-hopping spread-spectrum signal generating and capturing system for cluster links, and belongs to the technical fields of aviation data links and radio navigation. Background technique [0002] In the field of aviation data link and radio navigation, most missions require fleet links to provide good stealth characteristics, higher confidentiality, lower probability of interception, higher anti-interference, and higher measurement accuracy. Therefore, in the cluster link asynchronous communication and measurement system, it is a feasible method to consider the use of long code spread spectrum similar to GPS navigation signals, which can modulate 1023bit short codes (C / A codes) on the in-phase I branch of QPSK modulation ) spread spectrum, modulate the encrypted long code (P code) spread spectrum on the orthogonal Q branch, or both branches adopt long code spread spectrum modulation. The capture and tracking of ...

AI Technical Summary

Problems solved by technology

[0003] The use of long codes has many advantages, but it also brings a series of problems, and the flexibility is poor, which is not conducive to the self-organizing networking of the cluster formation task, the joining / exit of member nodes at any time, the variety of formation topology configurations, and the requirements of the task stage. change, wait

Although it is more convenient to use short-code spread spectrum, it greatly reduces the security, confidentiality, and anti-interference characteristics. It is often used to change the code pattern irregularly to obtain certain stealth, confidentiality, and anti-interference characteristics, but it can only be maintained for a period of time, not the final solution. Method

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