| Spatial multiplexing and space diversity gain of a system can be extracted through MIMO technique. An effective method to realize MIMO is using Space-Time Coding(STC)technique. So far there are two forms of STC: STTC and STBC. When the number of the antennae is not changed, the complexity of STTC decoding would increase on index with the acceleration of the transmission rate.However, STBC overcomes the limitation of STTC that its decoding is very complexly. It makes use of ML decoding arithmetic which possesses orthogonal designs. Although the structure of STBC decoding is very simple, it can achieve the same diversity gain as the method of MRC, and its use of the spectrum is very high. Because of these advantages, STTB is referred into the 3GPP1. Therefore, the research targets of this dissertation are to realize the coding and the decoding of STBC after studying its theory.The researches in this dissertation base on a platform which concludes TMS320VC5509A DSP and other chips, and this platform can accomplish the scheme of STBC which has two transmit antennae and two receive antennae. At first, significance of research, key technique and the development status of STBC is introduced briefly. Next, basic principles and capacity of MIMO, the theory of space-time block codec are presented in detail; two examples for decoding are enumerated.Finally, a total design scheme that realizes the STBC is shown and the software which supports the platform is also given. In the part of the hardware, how to select chips is introduced, including DSP and other chips, such as power supply,SDRAM,FLASH and JTAG which is a emulator interface; In addition, the clock,assignment to memory and the table of vectors are set. However, in the part of the software, the schemes to programme coder and decoder are expatiated separately and the final flow charts are drawn after that. During the design of the coder, the selection of the information source and the modulation is discussed. According to the characteristic of the multi-phase modulation ML... |
