期刊名称：International Journal of Multimedia and Ubiquitous Engineering
印刷版ISSN：1975-0080
出版年度：2016
卷号：11
期号：8
页码：397-410
出版社：SERSC
摘要：In this paper, to reduce PAPR (Peak-to-Average Power Ratio) in AF (Amplify and Forward) cooperative multicarrier system, an SLM-TR (Selective Mapping-Tone Reservation) joint optimization algorithm based on CAZAC (Constant Amplitude Zero Auto-Correlation) sequence is proposed. In our proposed method, several carriers are reserved for tone candidates, and then SLM (Selective Mapping) algorithm is utilized for the remaining data carriers. In SLM procedure, CAZAC sequences are utilized as the initial phase vector candidates and phase vector optimization is further processed by using feedback phase rotation algorithm for data carriers. After that, in continued TR (Tone Reservation) operation, random sequence is considered as the initial tone sequence and further optimized and subtracted from the modified data signal for peak cancelling using cyclic transposition searching algorithm to further reduce PAPR. Finally, the signal with the lowest PAPR is transmitted. By doing so, not only exhausting searching for optimal phase vectors is avoided efficiently, but also additional PAPR reduction is achieved by tone sequence modification. Simulation results show that the proposed method can reduce PAPR considerably and improve BER (Bit Error Rate) performance effectively, with insurance of high spectrum efficiency, low complexity and low loss in power efficiency. The influences of several conditions such as HPA (High power Amplifier) type, initial phase vector number, tone carrier number and sequence type are discussed to improve system QoS(Quality of Service).
