本文選題：DS-SS信號 + 參數(shù)估計��； 參考：《北京郵電大學(xué)》2008年碩士論文

【摘要】： 由于現(xiàn)代通信技術(shù)和檢測技術(shù)的飛速發(fā)展,推動了對通信對抗技術(shù)的深入研究。擴頻信號作為一種難預(yù)測的偽隨機、寬帶、低電平信號,具有抗干擾性強、截獲概率低、可實現(xiàn)碼分多址與高精度定時定位等優(yōu)點,因而被廣泛應(yīng)用于移動通信、雷達、導(dǎo)航(GPS)和測量等多種領(lǐng)域。對直接序列擴頻(DS-SS)信號的偵察已引起人們的極大關(guān)注,并開展了這方面的研究工作,其中對DS信號及直擴碼分多址(DS/CDMA)信號進行盲檢測與估計是首要任務(wù)。 直擴通信信號檢測與估計的研究已發(fā)展出很多方法,不過這些方法基本都是基于常規(guī)信號的檢測與估計方法,而直擴信號是寬帶微弱信號,不符合常規(guī)信號的處理方法,因此當(dāng)直擴信號的信噪比較低時,這些常規(guī)估計方法的估計性能惡化,甚至根本得不到正確的估計結(jié)果。從目前的研究發(fā)展情況來看,直擴通信信號的估計方法研究進展還比較緩慢,具體估計方法的研究還不夠全面成熟。 本文的主要工作是在未具有任何先驗知識的情況下,對DS-SS信號的參數(shù)進行盲檢測與估計,主要研究了平方倍頻檢測、自相關(guān)函數(shù)檢測、高階累積量檢測等方法,進行了詳細的理論分析和仿真驗證,并提出了一些新的思想和方法。上述三種方法都能完成低信噪比情況下的DS-SS信號檢測,各自對信號的某一個參數(shù)特征有很好的估計性能。其中平方倍頻檢測與相關(guān)累積技術(shù)相結(jié)合能夠較精確的估計信號的載波頻率;自相關(guān)函數(shù)檢測方法利用DS信號的時域特征,將其與二次譜相結(jié)合能夠完成對準(zhǔn)確地提取信號的偽碼周期,而其二階矩又能夠很好地估計擴頻信號的載頻;高階譜技術(shù)是直接序列擴頻信號檢測的另一途徑,其中基于四階累積量2-D非對角切片的檢測方法能夠很好地抑制高斯白噪聲,并且兼顧了時域相關(guān)檢測和平方倍頻檢測兩種方法的特點,能夠同時估計出擴頻碼周期和載波頻率兩個參數(shù)。
[Abstract]:With the rapid development of modern communication technology and detection technology, the research of communication countermeasure technology is promoted. As a kind of pseudorandom, wideband and low level signal, spread spectrum signal has the advantages of strong anti-jamming, low probability of interception, and can realize code division multiple access (CDMA) and high precision timing positioning, so it is widely used in mobile communication, radar, etc. Navigation GPS) and measurement and other fields. The detection of direct sequence spread spectrum (DS-SS) signals has attracted much attention and research work has been carried out. Blind detection and estimation of DS signals and DS / CDMA signals is the primary task. Many methods have been developed for the detection and estimation of DSSS communication signals, but these methods are basically based on the detection and estimation of conventional signals, and the DSSS signals are wideband weak signals, which do not conform to the processing methods of conventional signals. Therefore, when the SNR of DSSS signal is low, the estimation performance of these conventional estimation methods is deteriorated, and even the correct estimation results are not obtained at all. According to the current research and development, the research progress of DSSS signal estimation method is still slow, and the research of specific estimation method is not comprehensive and mature enough. The main work of this paper is to detect and estimate the parameters of DS-SS signal without any prior knowledge. The methods of squared double frequency detection, autocorrelation function detection, high order cumulant detection and so on are studied. Detailed theoretical analysis and simulation verification are carried out, and some new ideas and methods are put forward. The above three methods can detect DS-SS signals with low SNR, and each has good estimation performance for a certain parameter feature of the signal. The square double frequency detection combined with the correlation accumulation technique can accurately estimate the carrier frequency of the signal, and the autocorrelation function detection method utilizes the time-domain characteristics of the DS signal. Combining it with quadratic spectrum, the pseudo-code period of accurately extracted signal can be completed, and its second moment can estimate the carrier frequency of spread spectrum signal very well, and high order spectrum technology is another way to detect direct sequence spread spectrum signal. The detection method based on 4-order cumulant 2-D non-diagonal slice can suppress Gao Si white noise very well, and it takes into account the characteristics of time domain correlation detection and square frequency doubling detection. The two parameters of spread code cycle and carrier frequency can be estimated simultaneously.
【學(xué)位授予單位】：北京郵電大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2008
【分類號】：TN914.42

【引證文獻】

相關(guān)期刊論文 前1條

1 劉鵬;楊建波;劉武剛;;基于延時相乘及其改進方法的JTIDS信號檢測[J];通信對抗;2010年02期

相關(guān)碩士學(xué)位論文 前3條

1 王利萍;基于HHT的直擴信號檢測與參數(shù)估計[D];解放軍信息工程大學(xué);2009年

2 時魁;半盲擴頻系統(tǒng)載波頻率估計和窄帶干擾抑制研究[D];西安電子科技大學(xué);2011年

3 濮俊杰;非周期性擴頻信號的檢測與估計[D];杭州電子科技大學(xué);2009年

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本文編號：1857827