WMAN-OFDM Baseband System Simulation And Study About PAPR Reduction

At present, Orthogonal Frequency Division Multiplexing (OFDM) is one of the most promising technologies. It can stand against multi-path fading and narrowband interference, and it also has a high spectral efficiency. So it is considered as the key technology in the next generation wireless communication. However, the OFDM still has some drawbacks, one of which is its high peak-to-average power ratio (PAPR) of the transmitted signal. Accordingly, OFDMA technology derived from OFDM has a higher PAPR.WiMAX has become the best scheme of last one kilometers access, whose main physical technology are OFDM and OFDMA, so it supports the fix and mobile access and contain two main standards: IEEE802.16-2004 and IEEE802.16e. Based on the former standard, the paper designs a baseband system simulation platform by Matlab6.5.The thesis focus on studying some techniques for PAPR reduction, and principles of these techniques are described and their advantages and disadvantages are analyzed. Clipping and tone reservation techniques are simulated especially. The results show that both techniques are effective in reducing a high PAPR. Finally, we conclude the technique evolutions in OFDMA.