A coding technique to reduce PAPR and interference of OFDM systems
Orthogonal frequency-division multiplexing (OFDM) has been considered for many high-speed wireless applications. Indeed, the orthogonal properties among subcarriers of OFDM lead to high spectral efficiency and excellent ability to cope with multipath fading environment. However OFDM systems have two major drawbacks: high peak-to-average ratio (PAPR) due to summing up of large number of subcarriers data together and intercarrier interference (ICI) because the orthogonal properties are easily broken down by frequency offset errors caused by oscillator inaccuracies. In this thesis, a coding technique is proposed to reduce both drawbacks. The scheme has tightly bounded PAPR and good error correction capability while reducing ICI significantly. The proposed technique is based on Reed-Muller codes and Golay complementary sequences. It is shown, and confirmed by simulation, that the proposed method maintains PAPR of 3 dB (9 dB and 12 dB reduction in case of N = 16 and N = 32, respectively, where N is number of OFDM sub-carriers) and reduced ICI by 4 dB (for both N = 16 and N= 32 ).^
Besma Smida, Purdue University, David Kozel, Purdue University, Howard Gerber, Purdue University.
Engineering, Electronics and Electrical