多指数连续相位调制解调技术研究

发布时间：2018-07-12 19:40

本文选题：连续相位 + 频带利用率　；参考：《西安电子科技大学》2014年硕士论文

【摘要】：多指数连续相位调制(Multi-h CPM)体制的包络恒定并且相位连续。该体制拥有多个不同的调制参数,通过调整这些参数既可以得到较好的抗误码性能也可以得到较好的频谱性能。正是由于Multi-h CPM体制具有以上的优点,因此它受到了测控通信研究人员的广泛关注。本文对Multi-h CPM体制的解调技术进行了研究,主要包括以下四个方面的工作:1.对Multi-h CPM信号的调制模型以及解调模型进行了研究。CPM调制信号的相位承载着要传送的数据信息,并且相位具有记忆性。CPM体制最佳的解调方式是最大似然序列检测(MLSD)。该解调结构主要包括前端的匹配滤波器组和后端的的网格译码器。匹配滤波器负责将参考信号和接收信号进行相关,从而得出判决度量。网格译码器使用Viterbi算法获得最大似然译码结果。2.对Multi-h CPM信号的多种减复杂度算法进行了研究。为了降低解调复杂度,本文主要分析了三种算法,分别为频率脉冲截断、Walsh空间分解以及PAM分解。这一部分不仅给出了每一种算法的误码率曲线,并且分析了解调的复杂度以及采取减复杂度算法之后相应的性能损失。通过将减复杂度算法和最佳解调算法进行对比即可发现,解调复杂度和性能损失是相互矛盾的。3.对Multi-h CPM信号的软输出维特比算法进行了研究。为了能够更可靠更远的通信,需要把CPM调制与编码技术结合起来使用,然后在解调时使用软判决和Viterbi算法,这样可以获得最优的性能增益。软输出维特比算法和维特比算法的处理步骤基本是一样的,区别仅在于软输出维特比算法引入了先验信息,并且在解调的过程中会产生软信息。该软信息将作为后面级联的译码器的输入,从而得到译码后的比特信息。4.对Multi-h CPM信号的一种减复杂度算法(脉冲截断)的工程可实现性进行了研究。首先分析了算法的原理并且画出算法的仿真流程图。然后分别从时间和空间两个方面对复杂度进行了分析。最后使用仿真中具体的参数给出了复杂度的数量级。
[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.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN911.3

【相似文献】