本文選題：連續(xù)相位 + 頻帶利用率��； 參考：《西安電子科技大學(xué)》2014年碩士論文

【摘要】：多指數(shù)連續(xù)相位調(diào)制(Multi-h CPM)體制的包絡(luò)恒定并且相位連續(xù)。該體制擁有多個不同的調(diào)制參數(shù),通過調(diào)整這些參數(shù)既可以得到較好的抗誤碼性能也可以得到較好的頻譜性能。正是由于Multi-h CPM體制具有以上的優(yōu)點,因此它受到了測控通信研究人員的廣泛關(guān)注。本文對Multi-h CPM體制的解調(diào)技術(shù)進行了研究,主要包括以下四個方面的工作:1.對Multi-h CPM信號的調(diào)制模型以及解調(diào)模型進行了研究。CPM調(diào)制信號的相位承載著要傳送的數(shù)據(jù)信息,并且相位具有記憶性。CPM體制最佳的解調(diào)方式是最大似然序列檢測(MLSD)。該解調(diào)結(jié)構(gòu)主要包括前端的匹配濾波器組和后端的的網(wǎng)格譯碼器。匹配濾波器負責將參考信號和接收信號進行相關(guān),從而得出判決度量。網(wǎng)格譯碼器使用Viterbi算法獲得最大似然譯碼結(jié)果。2.對Multi-h CPM信號的多種減復(fù)雜度算法進行了研究。為了降低解調(diào)復(fù)雜度,本文主要分析了三種算法,分別為頻率脈沖截斷、Walsh空間分解以及PAM分解。這一部分不僅給出了每一種算法的誤碼率曲線,并且分析了解調(diào)的復(fù)雜度以及采取減復(fù)雜度算法之后相應(yīng)的性能損失。通過將減復(fù)雜度算法和最佳解調(diào)算法進行對比即可發(fā)現(xiàn),解調(diào)復(fù)雜度和性能損失是相互矛盾的。3.對Multi-h CPM信號的軟輸出維特比算法進行了研究。為了能夠更可靠更遠的通信,需要把CPM調(diào)制與編碼技術(shù)結(jié)合起來使用,然后在解調(diào)時使用軟判決和Viterbi算法,這樣可以獲得最優(yōu)的性能增益。軟輸出維特比算法和維特比算法的處理步驟基本是一樣的,區(qū)別僅在于軟輸出維特比算法引入了先驗信息,并且在解調(diào)的過程中會產(chǎn)生軟信息。該軟信息將作為后面級聯(lián)的譯碼器的輸入,從而得到譯碼后的比特信息。4.對Multi-h CPM信號的一種減復(fù)雜度算法(脈沖截斷)的工程可實現(xiàn)性進行了研究。首先分析了算法的原理并且畫出算法的仿真流程圖。然后分別從時間和空間兩個方面對復(fù)雜度進行了分析。最后使用仿真中具體的參數(shù)給出了復(fù)雜度的數(shù)量級。
[Abstract]:The multi exponential continuous phase modulation (Multi-h CPM) system has a constant envelope and a continuous phase. The system has many different modulation parameters. By adjusting these parameters, the system can not only obtain better error resistance and better spectral performance. It is because the system of Multi-h CPM has the above advantages, so it is subject to measurement and control. In this paper, the demodulation technology of Multi-h CPM system is studied in this paper, including the following four aspects: 1. the modulation model of Multi-h CPM signal and the demodulation model are used to study the data of the.CPM modulation signal carrying the data, and the phase has the memory.CPM system. The best way of demodulation is the maximum likelihood sequence detection (MLSD). The demodulation structure mainly includes the matching filter bank of the front end and the grid decoder in the back end. The matched filter is responsible for the correlation between the reference signal and the received signal, thus obtaining the decision measure. The grid decoder makes the maximum likelihood decoding result.2. pair with the Viterbi algorithm. In order to reduce the complexity of the Multi-h CPM signal, this paper mainly analyzes three algorithms, which are frequency pulse truncation, Walsh space decomposition and PAM decomposition. This part not only gives the error rate curve of each algorithm, but also analyzes the complexity of the modulation and the reduction of complexity. By comparing the complexity and the best demodulation algorithm, it is found that the demodulation complexity and performance loss are contradictory.3. to the soft output Vitby algorithm of Multi-h CPM signal. In order to be more reliable and further communication, the CPM modulation and coding technology need to be combined. The soft decision and Viterbi algorithm are used in demodulation, and the optimal performance gain can be obtained. The processing steps of the soft output Vitby algorithm and the Vitby algorithm are basically the same, the difference is that the soft output Vitby algorithm introduces the prior information and produces soft information in the process of demodulation. The interest will be used as the input of the later cascaded decoder, thus the engineering realization of a reduced complexity algorithm (pulse truncation) of the Multi-h CPM signal after the decoding of the bit information.4. is studied. Firstly, the principle of the algorithm is analyzed and the simulation flow chart of the algorithm is drawn. Then, the complex two aspects of time and space are made, respectively. The complexity is analyzed. Finally, the order of complexity is given by using the specific parameters in the simulation.
【學(xué)位授予單位】：西安電子科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TN911.3

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1 張明明;多指數(shù)連續(xù)相位調(diào)制解調(diào)技術(shù)研究[D];西安電子科技大學(xué);2014年

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