Study of Various Algorithms on PAPR Reduction in OFDM System

摘要

Artificial Bee Colony algorithm (ABC) is a swarm intelligence algorithm proposed by Karaboga in 2005, which is inspired by the behavior of honey bees. In this paper we make use of this algorithm to reduce PAPR in OFDM. Orthogonal frequency division multiplexing (OFDM) is an attractive technique for wireless high-rate data transmission as it minimizes effect due to frequency- selective fading channels. However, OFDM has some drawbacks in the transmission system. One of the major problems of the OFDM system is that OFDM signal has higher peak to-average-power ratio (PAPR) than single carrier signal because OFDM signal is the sum of many narrowband signals in the time domain. The high PAPR can cause inter-modulation and out-of-band radiation due to power amplifier nonlinearity. Therefore, it is highly desirable to reduce the PAPR of an OFDM signal. Many methods have been proposed including Partial Transmit Sequence (PTS), Selective Level Mapping (SLM) and some more. Here a newly suboptimal method based on artificial bee colony (ABC-PTS) algorithm is proposed to search the better combination of phase factors.