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1、如今，人们对通信的业务种类和通信速率有了越来越高的要求，要求移动通信也能和固网通信一样有高质量、 宽带性的保证。但是，通信带宽的增加必然会 带来严重的多径干扰，使信号受到频率选择性衰落影响。SCFDE技术是抗频率选择性衰落很好的方法，其为抵抗多径干扰提供了一个可行的低复杂性的解决方 案。同时，CPM信号由于其良好的恒包络特性，并且频谱利用率高，功率效率 高，已经得到了非常广泛的应用。因此，将 CPM信号和SCFDE结合有着非常 良好的应用前景。论文首先对 CPM信号和 SCFDE各自的优势进行了分析，并给出了 CPM-SCFDE的研究现状。紧接着，进一步阐述连续相位调制原理，包括了它的 功率谱
2、特性和欧氏距离情况，同时比较了 SCFDE和OFDM两者系统的差别，并 着重深入分析了 SCFDE的原理。然后，对无线衰落信道建模，采用经典的离散 冲击响应模型，本系统仿真采用的信道为典型的城市衰落信道和空地信道。其次，论文集中研究了 CPM单载波频域均衡接收机同步算法，包括到达检 测、定时误差估计、频率偏差估计和初始相位估计，并在衰落信道下一一进行了 仿真分析；介绍了补偿定时的内插技术原理及实现， 并针对高速数据传输系统设 计中可能会出现的参数漂移情况提出了环路跟踪解决方案。最后，我们将CPM和SCFDE技术结合，提出了 CPM信号运用频域均衡难 点的一个解决方案，即，使用相位归零法使添加循
3、环前缀后的CPM信号相位连续，并使用CPM离散线性表示进行频域均衡。先从信道信息在接收端已知的情 况入手，对空地信道和城市衰落信道进行仿真，分析了MSK和TCM-4CPM的仿真结果。之后，结合实际信道的情况，对信道、SNR进行估计，并设计了信道估计训练字。论文的最后，在实际信道的情况下，对MSK和TCM-4CPM的性能作出了整体的仿真。仿真结果表明，CPM应用频域均衡技术可以很好的对抗频率选择性衰落。【关键字】CPM SCFDE 同步估计 环路跟踪 正交分解Laurent分解信道估计预编码IAbstractToday, people have a ever- in creas ing dema
4、 nd in the variety of com muni cati on service and com muni cati on bit rate.They hope mobile com muni cati on can have high-quality, broadba nd features like the fix-l ine com muni cati on. However, the in crease of com muni catio n ban dwidth will in evitably lead to serious multi-path in ter-symb
5、ol in terfere nee, mak ing sig nals sufferi ng from freque ncy selective fadi ng effects. SCFDE tech no logy is a good way of an ti-fad in g. It provides a viable soluti on to multipath interference for low complexity .At the same time,the CPM signal has bee n a very wide range of applicati ons beca
6、use of its good characteristics of con sta nt en velope and high spectral efficie ncy, power efficie ncy. Therefore, the comb in ati on of CPM sig nal and SCFDE has a very great prospect.We first an alyzed the stre ngth of the CPM sig nal and SCFDE,a nd gave an acco unt of the CPM-SCFDE research lat
7、ely. Then, we further described the principles of con ti nu ous phase modulati on, in clud ing its power spectrum features and the Euclidea n dista nce.We compared the differe nces betwee n SCFDE and OFDM systems, and an alyzed the prin ciple of SCFDE in depth. Then, the wireless fading cha nnel is
8、modeled, using the classical discrete impulse resp onse model. The cha nn els used in the simulation of this system were typical urban fading channel and air-gro und data link cha nn els.Secon dly, we focused on the synchroni zati on algorithms of CPM-SCFDE receiver, in cludi ng the arrival detectio
9、 n, timi ng error estimati on, freque ncy offset estimati on and initial phase estimation. Then the simulation of these algorithms in the fading cha nnel were carried out and an alyzed.We in troduced the in terpolatio n theory and impleme ntati on to compe nsate time error, and a loop track ing solu
10、ti on for parameter drift in high-speed data tran smissi on system.Fin ally, we comb ined CPM and SCFDE tech no logies,a nd solved the difficulties of CPM sig nal using freque ncy doma in equalizati on.We used the phase-zer oing method to ensure phase continuity of the CPM signal after adding cyclic
11、 prefix , and used discrete lin ear represe ntati on of CPM for freque ncy-doma in equalizati on. The n beg in with cha nnel state in formatio n known at the recei ving en d,we simulated and an alyzed MSK and TCM-4CPM sig nals over the air-grou nd data link chann els and urba n fadi ng cha nn el.The
12、 n the actual situati on of the cha nnel was take n in to acco unt, we estimated the cha nnel in formatio n and SNR,desig ned of the cha nnel estimati on training word. At last, we maked the overall simulation of MSK and TCM-4CPM sig nals in the actual cha nnel case. Simulati on results showed that, CPM sig nal comb ining with freque ncy doma in equalizatio n tech no logy can be a good way of fighting against frequency-selective fading.Key Words CPM SCFDE Synchroni zatio n LoopTracki ngOrthogonal Decomposition LaurentDecompositionChannel Estimati on Precode2