Reducing PAPR (peak-to-average-power ratio) in OFDM (orthogonal frequency division multiplexing) signal transmission

To our knowledge, there is no paper in the open literature dealing with how to reduce PAPR. We now propose a method that can do it. CPM (continuous phase modulation) offers higher channel utilization and requires lower baseband power because of its smooth phase transfer characteristics. In the full paper, we explain in some detail our new method and the analysis of its simulation results; in this abstract, we just add some pertinent remarks to listing the two topics of explanation. The first topic is: OFDM-CPM transmission system. In this topic, we establish a mathematical model for the OFDM transmission system. Then, also in the first topic, we analyze the multi-amplitude CPM using double-value CPM constellation to illustrate how to reduce PAPR value. Still in the first topic, we study how to combine the multi-amplitude CPM with PTS (partial transmit sequence) algorithm. The algorithm uses various sequences to do weighted calculation of OFDM signals and transmit only those of smaller PAPR value. The second tropic is; simulation results and their analysis. In this topic, we simulate the algorithm that uses the modulation indices of 1/2 and 2/3 respectively. The simulation results, given in Fig.3 and Fig.4 in the full paper, show preliminarily that, when the multi-amplitude CPM signals combined with PTS are used, the PAPR value of OFDM-CPM transmission system is much smaller than that of the system which does not use the algorithm, and more importantly, the algorithm does not magnify the complexity of the system implementation.