Implementation And Optimization On Key Technology In TD-SCDMA Physical Layer Based On GPP

With the great development of communication technology, the application of software radio in the mobile communication system will become a significant research direction of this area in future. The researchers in the communication field have paid much attention to TD-SCDMA of which China owns the independent intellectual property rights. Meanwhile, with the Microsoft Research Asia’s successful implementation of SORA, the development model which applies software radio technology a signal processing platform based on general purpose processor, has attracted more and more attention, how to develop a real-time communication system based on GPP will become a research hotspot.On the background mentioned above, this paper describes how to implement key technology of TD-SCDMA based on GPP by applying software radio and then analyzessome results of platform’s performance and time delay. The most important point in the paper is to figure out the design, implementation and optimization of the main module of TD-SCDMA system and the two key module-joint detection and beanforming. After offering the basic concepts of TD-SCDMA system and the signal processing procedure, this paper gives the implementation of module in the system arid adopts ZF-BLE and rule of maximum receiving power as method of joint detection and beanforming. Then, using looking up table, IPP library and SIMD to optimize all kinds of the modules to decrease time of signal processing.The most important innovation point in this paper is that, when dealing with the optimization of beanforming, considering the great amounts operations of multiplication between plural matrixes, this paper comes up with a optimizing method that using a combination of several kinds of SIMD instructions to optimize the multiplication between plural vector and plural matrix, or between plural matrixes. This optimizing method applies simple SIMD instructions of arithmetic instead of complex computation, so decrease the signal processing time delay, and increase the data throughput.This paper shows the performance and time delay of uplink and downlink(with beanforming), and proves the effect of optimizations. The results tell that the TD-SCDMA communication system prototype based on generational purpose processor can reach the requirement of real time and bit error rate, what’s more, proving the feasibility of application of GPP in the communication system. With the development of wireless communication technology, application of both generational purpose processor and software radio will be hotspot in theoretical research and implementation, the prototype designed by this paper offers great experience of implementation based on generational purpose processor by software radio technology.