【作者】 冯琳；

【导师】 陆阳；

【作者基本信息】 合肥工业大学 ， 计算机科学与技术， 2014， 博士

【摘要】 设计无线通信系统方案时需要兼顾通信的可靠性和有效性。采用优良的基带编码可以降低误码率,从而提高传输的可靠性；采用分集技术克服无线信道的衰落也可以提高传输的可靠性；采用高效的复用、多址技术可以提高系统的频谱效率,从而提高传输的有效性。本文从无线通信基带设计出发,以提高可靠性与有效性为目标,主要工作如下：论文在充分分析序列设计理论相关函数界以及Golay码和LS码已有研究成果的基础上,从解方程的角度设计LS码种子,并对递归树图生成LS码方法进行分析,对其一般性质进行了论证和总结；发现了Hadamard矩阵通过分裂可以构造出组内自相关互相关函数不理想、组间互相关函数理想的新型互补码,其与LS码在性能上有较大的区别。论文对扩展LS码进行了研究,将编码元素扩展至整个复数域,并且对扩展矩阵A的构造和性质进行了深入研究,得出了构造一般性扩展矩阵的方法。随后,将互补码的范畴推广至广义互补码。在已有理论的基础上,受LS码结构和性质的启发,引入具有零相关窗特性的广义互补码的构造,以及扩展广义互补码的构造；并对这两类新型广义互补码结构性质进行了分析和证明。论文对互补序列设计理论研究成果进行应用,改进了一种以LTE-Turbo码作为前向纠错码的基于互补码的发射分集方案,即ZCW-STTD。该方案充分结合了互补码理想自、互相关函数的优势,以及Turbo码强大纠错能力的优势。在相同条件下,该方案能够比单发单收系统以及其他学者提出的方案在频率选择性信道下获得更大的频率分集增益、空间分集增益,以及编码增益,并且收发机结构简单,易于工程实现。受前述序列信号设计的启发,给出了一种对OFDM信号进行改造的新型信号设计方式。这种设计的重点是将OFDM信号子载波之间的最小频率间隔进一步缩小,再利用Gram-Schmidt正交化设计出一组新的正交信号,这组新的正交信号称为GSFDM信号,该技术称为GSFDM技术。使用GSFDM技术进行数据传输；其频谱效率高于传统的OFDM技术,并且误码性能不会恶化。信息论中脏纸编码对这种信号处理方法提供了理论依据,仿真结果也验证了本方法的正确性。更多还原

【Abstract】 Design of wireless communication system requires high reliability and effectiveness. In order to improve transmission reliability, a good baseband signal design is useed to reduce interference. And diversity technique is also used to overcome channel fading. In order to improve transmission effectiveness, efficient multiplexing and multiple access technology is adopted to improve system spectral efficiency. This thesis focuses on the following aspects.Correlation function bounds of sequence design theory and existing research results of Go lay code and LS code are reviewed. And then by solving equations, LS code seed is designed. Method of generating longer code through a binary tree is analyzed and its general nature are demonstrated and summarized. Subsequently a new complementary code with non-ideal auto-correlation function but ideal cross-correlation function between the two groups is found by splitting a Hardamard matrix. It is essentially different from the LS code.Furthermore, the extended LS code is also deeply studied. Sequence elements are extended to the whole complex number field. By studying of constructing extended matrix A and its nature, a method of constructing general extended matrix is proposed. The concept of complementary code is extended to generalized complementary code. Based on existing theories and inspired by the structure and properties of LS codes, generalized complementary code with zero correlation window and extended generalized complementary code are constructed. Besides, the structural properties of the two novel generalized complementary codes are analyzed and proved.A transmit diversity scheme using complementary code in frequency selective fading channel, namely ZCW-STTD is improved. LTE-Turbo code, which acts as forward error correction code, is utilized as channel coding scheme. This scheme combines the advantages of the ideal autocorrelation and cross-correlation of complementary codes and powerful error correction capability of Turbo codes. Under the same conditions, it is better than single transmitting and single receiving system as well as schemes proposed by other scholars in frequency selective channel. It can obtain greater frequency diversity gain, spatial diversity gain and coding gain, and the transceiver structure is simple and easy to be implemented in engineering.A new signal design method by modifying the OFDM signal is proposed. The main idea of this kind of signal design is that the minimum frequency spacing between the sub-carrier of OFDM signal is further reduced. In addition, a new set of orthogonal signals are designed by Gram-Schmidt orthogonalization. This new set of orthogonal signals is called GSFDM signal, and this method is called GSFDM technique. By using GSFDM technique for data transmission, the spectral efficiency is larger than traditional OFDM technology if using the same modulation scheme and BER performance does not deteriorate. Dirty paper coding of information theory provides theoretical basis for this signal processing method. Simulation results also verify the correctness of the method.更多还原