Research On Channel Estimation And Equalization For WiMAX

WiMAX based on IEEE802.16 is a broadband wireless access technology. It is used in fixed, nomadic, portable, simple mobility and free movement, etc. In recent years, with the development of wireless access technology, WiMAX is becoming the focus of attention gradually. It has the advantage of coverage, access speed, QoS and security, etc. The deployment of WiMAX is faster than cable access, and the expansion of WiMAX is also stronger than cable access. In addition, it has anti-multipath fading capability and high spectral efficiency because of using orthogonal frequency division multiplexing. Now, WiMAX has begun to be applied in Europe, America, Japan and South Korea. In China, China Netcom and China Telecom has been tested and applied in the business field. Channel estimation and equalization is the key technology of WiMAX and It's accuracy greatly impacts on the system performance. So this paper will research on the channel estimation and equalization for WiMAX, and to do simulation for the physical layer of WiMAX.First, according to the principles of OFDM and DFT, this paper sets up the OFDM system simulation model based on the FFT . The signal transmitter and receiver are realized in this model. Second, this paper does the research and simulation on channel estimation algorithm, such as LS, MMSE, Interpolation and so on. MMSE algorithm is superior to LS algorithm from the Simulation results. But MMSE has more complexity than LS .Third, this paper researches on the equalization algorithm such as ZF equalization, MMSE equalization and does simulation of these. Finally this paper set up the WiMAX system simulation model which is based on the IEEE802.16e. The channel estimation and equalization algorithm are realized in this simulation.