A Study Of Channel Estimation Techniques Based On IEEE 802.16e Standard

With the fast development of Information Industry, computer and communication technologies continue to merge. The flourish of Internet accelerates the process of mergence. Nowadays the global communication industry displays the traits of Mobility, Broadband and IP-based Architecture. And the appearance of IEEE802.16e meets the trend of development. Wimax systems that support IEEE802.16e standard hold all the traits of Next Generation Mobile Communication systems.So Mobile WIMAX is a very promising Broadband Wireless Access technology. According to the distributed diagram of pilot, the method of channel estimation, two dimensions (2-D) Wiener filter is determined in this system support IEEE802.16e standard in this paper. Due to the complex structure of 2-D filter, it is often simplified to two linking 1-D filters which used to interpolate in time domain and frequency domain on the condition that performance has minimal influence. In the environment of IEEE802.16e OFDM system, the simulation results using improved 2×1 ? DWiener filter-a pilot assisted channel estimator widely used in OFDM systems by replacing Wiener filter in frequency domain with ML channel estimator was given. The improved estimator can provide better performance and lower complexity than 2×1 ? D Wiener filter in 802.16e OFDM system.According to structure of the preamble in DL OFDMA system that support 802.16e standard, the four algorithms are studied and compared for initial channel estimation.Based on cluster structure, different two-dimension interpolation filtering was proposed. All those methods are analyzed and compared in terms of their computational complexity, mean square error and bit error rate performances.