水下艦艇擴(kuò)頻通信體制研究

摘" 要： 水下艦艇通信采用的水聲通信方式在長距離傳輸中信號衰減嚴(yán)重，且因為隱蔽性需求信號功率受限，疊加受到多徑干擾和海洋背景噪聲干擾，通信誤碼率較高。為此，提出水下艦艇擴(kuò)頻通信體制研究。設(shè)計擴(kuò)頻通信體制，利用擴(kuò)頻通信體制拓寬傳輸帶寬，提升遠(yuǎn)距離衰減下的通信信噪比；采用類白噪聲的偽隨機(jī)碼m序列和OPS序列作為擴(kuò)頻碼組建編碼序列集，解決白噪聲干擾、多徑干擾和碼分多址的問題。測試結(jié)果表明：同等條件下，采用m序列的擴(kuò)頻通信結(jié)果更優(yōu)，可以實現(xiàn)-25 dB下誤碼率低于1%的可靠通信。經(jīng)過該方法調(diào)制后，剔除了噪聲干擾和多徑干擾，增強了衰減的高頻信號，解決了水下通信遠(yuǎn)距離衰減、多徑干擾、背景噪聲干擾等問題。

關(guān)鍵詞： 水下艦艇通信； 擴(kuò)頻通信； m序列； OPS序列； 誤碼率； 信噪比

中圖分類號： TN929.3?34" " " " " " " " " " " " " " 文獻(xiàn)標(biāo)識碼： A" " " " " " " " " " "文章編號： 1004?373X（2025）01?0107?05

Research on spread spectrum communication system of underwater vessels

LI Yao， ZHAO Jiankang， LONG Haihui

（School of Electronic Information and Electrical Engineering， Shanghai Jiao Tong University， Shanghai 200240， China）

Abstract： The underwater acoustic communication method used for communication on underwater vessels is confronted with severe signal attenuation in long?distance transmission， and due to the requirement of concealment， the signal power is limited and is affected by multipath interference and ocean background noise interference in a superposition manner， resulting in high communication error rate. Therefore， this article proposes the study of underwater vessel spread spectrum communication system. A spread spectrum communication system is designed， and the spread spectrum communication system is utilized to expand transmission bandwidth， so as to improve communication signal?to?noise ratio （SNR） under long?distance attenuation. Pseudo?random code m?sequences and OPS sequences similar to white noise are used as spreading codes to construct an encoding sequence set， so as to get rid of white noise interference， multipath interference and code division multiple access （CDMA）. The test results show that under the same conditions， the spread spectrum communication using m?sequences yields better results and can achieve reliable communication with an error rate below 1% at -25 dB. After the modulation with the proposed method， noise interference and multipath interference are eliminated， and the attenuated high?frequency signal is enhanced， so the problems of long?distance attenuation， multipath interference and background noise interference in underwater communication are eliminated.

Keywords： underwater vessel communication; spread spectrum communication; m?sequences; OPS sequence; bit error rate; SNR

0" 引" 言

低頻水聲信號可以在海洋中傳播數(shù)百公里，因此常用于水下艦艇通信[1?2]。但在實際應(yīng)用場景中，水下艦艇需要限制信號發(fā)射功率，確保信號隱藏在海洋背景噪聲中，以免被敵方水聲探測設(shè)備發(fā)現(xiàn)[3]。遠(yuǎn)距離的水下信號傳播中，使水聲信號具有衰減效應(yīng)[4]。同時，由于聲速分布不均勻造成水聲傳播的時間差[5?6]，這使得通信信號具有嚴(yán)重的多徑效應(yīng)。為此，有必要對克服遠(yuǎn)距離衰減、多徑干擾和噪聲干擾等問題的水下通信體制進(jìn)行研究。

文獻(xiàn)[7]采用自適應(yīng)調(diào)制編碼方式、實時調(diào)整編碼方式等設(shè)計通信體制參數(shù)，該方法僅補償多普勒信號，應(yīng)用在水下傳輸中，傳輸帶寬較低，導(dǎo)致通信信噪比較低?！?br>