| Orthogonal Frequency Division Multiplexing (OFDM) technology is known for its convenience of implementation, as well as other characteristics such as the high spectrum efficiency, the anti-multipath fading capability and its unique effective suppression of the inter-symbol interference (ISI) and the inter-carrier interference (ICI), which has been successfully applied in many high-speed wireless communication systems and become the next generation mobile communication system standard. Nevertheless, a higher peak-average power ratio (PAPR) of the equipment to the system brought about a heavy burden of OFDM, which greatly limits the widespread application of OFDM technology. Naturally, how to reduce PAPR becomes a problem in the realm of wireless communication.In this thesis, starting with the basic principles of OFDM technology, the author offers a detailed analysis of the cause of high PAPR, as well as several key technologies to solve this problem. Based on this focus, the author selects the Partial Transmit Sequences (PTS) algorithm. PTS is a non-distortion technology aiming at reducing the value of PAPR and simultaneously not causing the signal distortion. However, the main stumbling point of PTS algorithm is its higher computational complexity.In this thesis, referencing to various existing PTS comparative analysis of simulation algorithms, the author makes several suggestions to reduce the computational complexity as much as possible by means of the simulation analysis which ensures system performance; through studying in the field of neural networks, immune genetic algorithm processes the advantage of dealing with large-scale and complex search problems. The author applies the immune genetic algorithm to the research of PTS algorithm which solves the optimal weighting factor of the search issue, and makes some advices to reduce the specific applications of PAPR. Meanwhile, the effectiveness of the algorithm has been confirmed through simulation analysis. |
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