一種Chirp信號的低復雜度頻譜分割與聚合方法

閻張懿 仇洪冰 鄭霖 張文輝

摘? 要： 通過對擴頻信號進行頻譜分割、置亂、頻譜插空和聚合恢復，不僅可以提高通信系統的頻譜利用率，而且起到了物理層加密和提高抗截獲能力的效果。但是，傳統信號的頻譜分割與聚合采用頻域濾波器組技術，算法復雜度高，實用性差，且更容易受到干擾影響。針對線性調頻（Chirp）擴頻信號，利用其時頻具有線性關系的特性，設計提出了一種基于時域成型窗算法，通過理論分析證明了與頻域濾波等價的效果，較大程度降低了頻譜分割聚合的復雜度，提高了聚合的魯棒性。仿真結果表明，在Chirp?BOK通信系統中，該方法在誤碼率以及復雜度方面均優于傳統頻域濾波算法。

關鍵詞： 抗截獲; 濾波器組技術; 頻譜分割; Chirp信號; 時域成型; 理論分析

中圖分類號： TN911.72?34? ? ? ? ? ? ? ? ? ? ? ? 文獻標識碼： A? ? ? ? ? ? ? ? ? ? ? ? 文章編號： 1004?373X（2020）13?0001?05

A method of spectrum division and combination for Chirp signal

YAN Zhangyi1， QIU Hongbing1， ZHENG Lin1， 3， ZHANG Wenhui2

（1. Guangxi Key Laboratory of Wireless Wideband Communication and Signal Processing， Guilin University of Electronic Technology， Guilin 541004， China;

2. Guangxi Cooperative Innovation Center of Cloud Computing and Big Data， Guilin University of Electronic Technology， Guilin 541004， China;

3. Key Laboratory of Communication Network Information Transmission and Distribution Technology， Shijiazhuang 050081， China）

Abstract： The spectrum division， scrambling， insertion and recombination recovery of the spread spectrum signal can not only improve the spectrum utilization rate of communication systems， but also improve the physical layer encryption and the anti?interception ability. However， the traditional signal spectrum division and recombination method adopts filter bank technology， which has high complexity and poor practicability， and is more susceptible to interference. In this paper， a time?domain shaping window algorithm is proposed to deal with the Chirp spread spectrum signal by utilizing the characteristic that its time?frequency has linear relationship. The theoretical analysis proves that its effect is equivalent to frequency domain filtering， which greatly reduces the complexity of spectrum division and recombination and improves the robustness of recombination. The simulation results show that， in Chirp?BOK communication system， this method is superior to traditional frequency domain filtering algorithm in terms of bit error rate and complexity.

Keywords： anti?interception; filter bank technology; spectrum division; Chirp signal; time domain forming; theoretical analysis