【摘要】：隨著無線通信網(wǎng)絡(luò)和移動(dòng)設(shè)備在人們?nèi)粘９ぷ骱蜕钪兄匾缘牟粩嗵嵘?對(duì)更加安全可靠的無線通信技術(shù)的需求也迫在眉睫。對(duì)于傳統(tǒng)的擴(kuò)頻或者跳頻通信系統(tǒng)而言,其信號(hào)和系統(tǒng)都是基于各態(tài)歷經(jīng)和循環(huán)平穩(wěn)理論來進(jìn)行設(shè)計(jì)的。對(duì)于具備各態(tài)歷經(jīng)性和循環(huán)平穩(wěn)性的信號(hào),無論從什么時(shí)間開始觀測(cè),經(jīng)過足夠長(zhǎng)時(shí)間后總是可以得到它的均值和自相關(guān)值,而且觀測(cè)值越多,其觀測(cè)精度越高。利用循環(huán)譜和高階譜等分析方法,即使在很低信噪比下,仍可以檢測(cè)到具備循環(huán)平穩(wěn)性的通信信號(hào)的通信參數(shù),從而完成通信信號(hào)的有效截獲。本文以非平穩(wěn)通信信號(hào)和系統(tǒng)的設(shè)計(jì)、實(shí)現(xiàn)和測(cè)試為主要研究?jī)?nèi)容,重點(diǎn)在原理樣機(jī)的實(shí)現(xiàn)和測(cè)試方面。首先介紹了非平穩(wěn)通信技術(shù)和傳統(tǒng)擴(kuò)頻、跳頻和跳時(shí)等通信技術(shù)的區(qū)別以及意義,還描述了目前國(guó)內(nèi)外學(xué)者在相關(guān)領(lǐng)域的研究現(xiàn)狀;接下來闡述了非平穩(wěn)通信系統(tǒng)的基本原理,包括非平穩(wěn)通信信號(hào)的基本構(gòu)造方法和特性、物理層幀結(jié)構(gòu)的結(jié)構(gòu)和功能、同步與檢測(cè)的基本原理等,并給出了非平穩(wěn)通信系統(tǒng)的整體框圖結(jié)構(gòu);然后給出了非平穩(wěn)通信原理樣機(jī)的設(shè)計(jì)結(jié)構(gòu),包括基帶模塊、中頻/射頻模塊和外設(shè)等;而后分別詳細(xì)介紹了非平穩(wěn)無線通信發(fā)射機(jī)和接收機(jī)的信號(hào)處理流程,并按照信號(hào)處理順序依次說明了各基帶模塊的原理和硬件實(shí)現(xiàn)方式;最后分別對(duì)內(nèi)場(chǎng)和外場(chǎng)通信性能實(shí)驗(yàn)測(cè)試的方法和流程進(jìn)行了介紹,給出了內(nèi)場(chǎng)測(cè)試時(shí)的信噪比計(jì)量方法,以及內(nèi)外場(chǎng)各項(xiàng)通信指標(biāo)的測(cè)試結(jié)果。本文的主要工作內(nèi)容和創(chuàng)新點(diǎn)如下:(1)針對(duì)傳統(tǒng)通信容易被檢測(cè)的弱點(diǎn),設(shè)計(jì)了非平穩(wěn)信號(hào)使得基于高階量累積等方法檢測(cè)信號(hào)的概率大大降低,顯著增強(qiáng)了安全性;(2)實(shí)現(xiàn)了具有完整功能的非平穩(wěn)通信系統(tǒng)原理樣機(jī)。實(shí)驗(yàn)測(cè)試表明,在很低信噪比(-18dB)條件下,系統(tǒng)具有良好的誤碼率性能,在無糾錯(cuò)編碼情況下接收誤比特率達(dá)到10-3,且能夠清晰地傳輸語音,驗(yàn)證了非平穩(wěn)通信系統(tǒng)的可靠性;(3)在實(shí)現(xiàn)過程中,對(duì)非平穩(wěn)無線通信系統(tǒng)進(jìn)行了一系列針對(duì)性的改進(jìn),包括各模塊時(shí)鐘同步問題,解調(diào)方式優(yōu)化等。
[Abstract]:With the increasing importance of wireless communication networks and mobile devices in people's daily work and life, the demand for more secure and reliable wireless communication technology is imminent. For traditional spread spectrum or frequency hopping communication systems, their signals and systems are designed based on ergodic and cyclostationary theories. For the signal with ergodicity and cyclic stationarity, the mean value and autocorrelation value can always be obtained after a long enough time, and the more the observed values, the higher the observation accuracy. By using the analysis methods of cyclic spectrum and high-order spectrum, the communication parameters of the communication signal with cyclic stationarity can still be detected even at very low SNR, so as to complete the effective interception of the communication signal. In this paper, the design, implementation and testing of non-stationary communication signals and systems are the main research contents, with emphasis on the realization and testing of the prototype. Firstly, the difference and significance between non-stationary communication technology and traditional spread spectrum, frequency hopping and time hopping communication technologies are introduced, and the current research status of scholars at home and abroad in related fields is also described. Then the basic principle of non-stationary communication system is described, including the basic construction method and characteristics of non-stationary communication signal, the structure and function of physical layer frame structure, the basic principle of synchronization and detection, and so on. The overall block diagram structure of the non-stationary communication system is given. Then the design structure of the prototype of non-stationary communication principle is given, including baseband module, intermediate frequency / RF module and peripherals. Then the signal processing flow of non-stationary wireless communication transmitter and receiver is introduced in detail, and the principle and hardware implementation of each baseband module are explained in turn according to the signal processing order. Finally, the method and flow chart of internal field and external field communication performance test are introduced, and the signal-to-noise ratio (SNR) measurement method and the test results of internal and external field communication indexes are given. The main contents and innovations of this paper are as follows: (1) aiming at the weakness that traditional communication is easy to be detected, the non-stationary signal is designed to greatly reduce the probability of signal detection based on high-order accumulation and significantly enhance the security; (2) the prototype of non-stationary communication system with complete function is realized. The experimental results show that the system has good bit error rate (BER) performance under the condition of very low signal-to-noise ratio (- 18dB). Under the condition of no error correction coding, the received bit error rate can reach 10 鈮，

本文編號(hào)：2477760