Mimo-ofdm Test System Infrastructure Software Platform Dsp Technology Research

With the rapid growth of wireless technology, the demand of users for information transmission is higher data rate and higher reliability, which can be satisfied by the emergence of MIMO-OFDM technology. The technology MIMO can not only take advantage of space multiplexing gain to raise channel capacity, but also make use of space diversity gain to raise the reliability, while OFDM uses the orthogonal sub-carriers to transmit data, increasing the spectrum availability as well as raising the transmission reliability by converting the frequency selecting attenuation channel to plain attenuation channel. Therefore, the combination of the technology MIMO and OFDM can improve the performance of wireless communication systems in a vast scale.In this paper, a wireless MIMO-OFDM communication testing system is studied. Based on software radio technology, this testing system takes FPGA plus DSP as its hardware platform as well as a typical MIMO-OFDM system architecture as its software platform which is made up of data transmission module(interface) and data process module to develop several data links. In the paper, the work includes finishing a significant part of the data transmission module, implementing a critical arithmetic to decrease the PAPR (Peak to Average Power Ratio), and finally developing a differential QPSK link to test the hardware and software platform of the testing system.The architecture of this paper is presented as below:In Chapter 1, to begin with, the characteristic of the wireless channel is introduced briefly, leading to the problems the wireless transmission needs to tackle; then, the corresponding methods are put forward, which is, the technology MIMO and OFDM; at the end, a common MIMO-OFDM system architecture is introduced.In Chapter 2, the overall project of the testing system is presented, giving the general overview of the hardware and software platform.In Chapter 3, the testing system's interfaces are designed and implemented, which includes the interfaces of DSP and SDRAM, DSP and ZBTSRAM, DSP and Dual Port SRAM and the serial interface-FPGA-DSP. In Chapter 4, the implementation of the technology to decrease the PAPR of the OFDM system is given. Firstly, the reason for high PAPR in the OFDM system is explained, then, an effective algorithm to decrease the PAPR is presented and implemented through DSP.In Chapter 5, the testing of the basic system software platform is given. This chapter constructs a differential QPSK communication system with a basic single antenna which is then used to give an overall test to the hardware and software platform.In Chapter 6, the conclusion of this paper including the main contents, results of research, and then next research goals are put forward.