TD-SCDMA软基带关键技术研究与实现

发布时间：2018-03-07 09:24

本文选题：C-RAN　切入点：Xenomai　出处：《电子科技大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着移动互联网时代的到来,传统无线接入网架构下的网络建设、运营和升级成本不断增长。为此,中国移动提出了新型无线接入网架构C-RAN。通过改变网络建设和部署的方式,C-RAN可经济有效地降低网络的建设和维护成本,并为用户提供灵活高效的服务。论文参考C-RAN架构和3GPP标准协议,采用通用处理器加模拟RRU的网络部署方式,研究了TD-SCDMA链路的收发结构和基带信号处理关键技术,并对其进行简化,最终在Intel处理器上实现了基带信号的实时处理。首先,分析TD-SCDMA物理层标准协议,研究基于匹配滤波的时间同步算法和矩阵求逆的联合检测算法。出于实时性的考虑,根据PN码正交性采用空间换时间的策略对算法进行简化。其次,设计基带信号处理方案并予以实现。根据算法相关性划分任务,在任务间合理分配处理器资源,设计任务间的通信机制以及任务详细处理流程,定义模块接口并给出模块间的调用关系。在此基础上编码调试,在内嵌Xenomai内核的Linux系统上实现12.2kbps和384kbps两种业务的基带信号实时处理。最后,评估系统性能。同步算法在-10dB信噪比条件下可达到0.98的接入概率;频偏估计在-3dB信噪比条件下能实现3Hz残余频偏的估计精度;系统在加性高斯白噪声信道条件下,误比特率性能与MATLAB定点仿真结果相差1dB。论文在通用处理器平台上实现了TD-SCDMA基带信号的实时处理,验证了通用处理器用于信号处理的可行性,可为C-RAN架构中的虚拟基带处理池设计提供参考。
[Abstract]:With the arrival of the era of mobile Internet, the cost of network construction, operation and upgrade under the traditional wireless access network architecture is increasing. China Mobile has proposed a new wireless access network architecture, C-RAN. By changing the way of network construction and deployment, C-RAN can effectively reduce the cost of network construction and maintenance. With the reference of C-RAN architecture and 3GPP standard protocol, this paper studies the transceiver structure of TD-SCDMA link and the key technology of baseband signal processing by using the general processor and analog RRU network deployment mode. Finally, the real-time processing of baseband signal is realized on Intel processor. Firstly, the physical layer standard protocol of TD-SCDMA is analyzed. The time synchronization algorithm based on matched filter and the joint detection algorithm based on matrix inversion are studied. For the consideration of real-time, the algorithm is simplified by the strategy of space changing time according to the orthogonality of PN code. Secondly, Design and implement baseband signal processing scheme, divide tasks according to algorithm correlation, allocate processor resources reasonably among tasks, design communication mechanism between tasks and detailed processing flow of tasks. The interface of the module is defined and the calling relation between the modules is given. On this basis, coding and debugging are carried out, and the real-time processing of the baseband signals of the two services is realized on the Linux system embedded in the Xenomai kernel. To evaluate the performance of the system, the synchronization algorithm can reach 0.98 access probability at -10dB SNR, the frequency offset estimation can achieve the accuracy of 3Hz residual frequency offset at -3dB SNR, and the system under the condition of additive Gao Si white noise channel, the estimation accuracy of the residual frequency offset can be achieved under the condition of -3dB signal-to-noise ratio (SNR). The performance of bit error rate is 1 dB different from that of MATLAB fixed-point simulation. In this paper, the real-time processing of TD-SCDMA baseband signal is realized on the general processor platform, and the feasibility of using the general processor for signal processing is verified. It can provide reference for the design of virtual baseband processing pool in C-RAN architecture.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN929.53

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