An Improved IDCT-OFDM with Partial Transmit Sequence

摘要

Orthogonal frequency division multiplexing (OFDM) has been adopted as a standard for various high data rate wireless communication systems due to the spectral bandwidth efficiency, robustness to frequency selective fading channels, etc. However, implementation of the OFDM system entails several difficulties. One of the major drawbacks is the high peak-to-average power ratio (PAPR), which results in intercarrier interference, high out-of-band radiation, and bit error rate performance degradation, mainly due to the nonlinearity of the high power amplifier. In this paper, a new technique that implements inverse discrete cosine transform (IDCT) along with PTS concept to get an improved PAPR reduction level were introduced. Simulations are performed with QAM modulation, 64 subcarriers and variety number of partitions and admitted angle phases. A comparison between the proposed technique with OFDM, PTS, and GDCT Precoded OFDM with PTS was conducted and the simulation result shows that the proposed technique surpass all three technique in term of PAPR reduction. Furthermore, the proposed technique can reduce the maximum OFDM PAPR level to 0 dB.