Study On The PAPR Of OFDM In Power Line Communication

With the rapid development of the technology of communications, people have paid more attention to power line communication. During the realization of communications between the inverters, we use OFDM as the communication scheme, which is based on the characteristics of transmission and interference of power line. A key problem is the peak to average power ratio during the realization of OFDM. At present, more people have studied on how to settle this problem. But a lot of them can't meet the challenge from complexity of calculation to practicability. This article lays emphasis on the compression of PAPR of the OFDM scheme realized the communications between the inverters Firstly, the author researches on the method of input sequence envelope scaling, aiming at reducing the complexity of this method, the author proposes a simplified method based on this method. Simplified method is realized through using threshold and calculation by iteration. We use two clusters during the research; the article has tested the effectivity of the simplified method through computer simulations. Secondly, this article discusses on the companding method to reduce PAPR. Although more articles has introduced this method, little about how to chose the parameter of companding, the article researches on the μ law companding method and discusses on how to chose the companding parameters, at the same time, the author analyses the performances of the system with different parameters through computer simulations. Finally, the author has realized OFDM signal in DSP. Companding method is used to the signal process, the validity of the method is tested.