A PAPR REDUCTION METHOD USING NEW ACE (ACTIVE CONSTELLATION EXTENSION) WITH HIGHER LEVEL CONSTELLATION

It is very important to reduce PAPR (peak to average power ratio) in the OFDM (orthogonal frequency division multiplexing) communication system. In this paper, we propose an ACE (active constellation extension) method to reduce PAPR without any date rate loss. In this method, the target PAPR is firstly set and then the clipping is used. Next, the active extending is made for the mapping the dispersive constellation onto the fixed point of extended constellation. The main advantage of this method is that it can meet target PAPR without any data rate loss. Unlike the conventional phase rotation method, the side information is not required in this method. So, we can get the target PAPR by the extension of the constellation level. We can reduce PAPR of 4dB by the 16-QAM extension, and can expect the target PAPR by the 64-QAM ACE. This ACE PAPR reduction method has more reduction capability, compared with the conventional SLM or PTS method. Also, it has lower BER (bit error rate) than ordinary same constellation level symbols.