Jijina N., Dr. Sakuntala S. Pillai, Senior member IEEE
The mobile WiMAX air interface adopts Orthogonal Frequency Division Multiple Access (OFDMA) as multiple access technique for its uplink and downlink transmission. All OFDMA based systems, including mobile WiMAX, experience the problem of high peak-to-average power ratio (PAPR). Each symbol block is linearly transformed by a precoding matrix before OFDM modulation and transmission in linear precoding. This paper provides a comparison of three typical linear precoding techniques: Hadamard transform precoding, Discrete Sine Transform precoding and Square root raised cosine function precoding used in OFDMA system. The performance of these different schemes in terms of PAPR reduction is analyzed with the conventional Random Interleaved OFDMA system.