Analysis And Research On Performance Of OFDM-CPM Modulation

As a new type of modulation technology, OFDM-CPM joint modulation has beenwidely studied in recent years. It not only has both the high spectrum efficiency andhigh power utilization characteristics, but also has the advantage of anti-multipathfading of OFDM technology. In this paper the performance of the OFDM-CPM systemis analyzed and researched.This paper introduces the basic principle of continuous phase modulation, thecharacteristics, modulation parameters of spectrum, and the principle, characteristicand parameter selection of OFDM systems; analyzes the characteristics ofOFDM-CPM signal and its subclasses signal. And the influence of modulation indexand M-ary number on the performance of all types of OFDM-CPM signal is alsostudied.This paper focuses on discussing the principle of the Optimum CPM andOFDM-CPM Receiver based on Maximum likelihood sequence estimation (MLSE),studying the system’s performance through simulation, and improving the performanceof OFDM-CPM system with channel coding (Convolutional code). In order to reducethe complexity and improve the performance of a receiver, three kinds of OFDM-CPMreceivers based on FFT are designed: the minimum bit error rate receiver, the sequenceaverage receiver and the receiver based on Viterbi algorithm. And performances of thethree receivers are compared and analyzed, which follows the verification of theOFDM-CPM system’s achievement of best balance between spectrum utilization rateand bit error rate.