摘要
由于多路正交频分复用信号是由多个不同频带的正交频分复用信号叠加而成的,其信号峰均比过大的问题较之单路正交频分复用信号更为严重,并且针对单路正交频分复用信号的降峰均比算法难以适用于多路正交频分复用系统,因此提出了分组部分传输序列算法和简化分组部分传输序列算法。这两种算法首先将多路正交频分复用信号进行分组并将组内信号相加,继而将相加得到的信号分别乘以一个相位旋转因子后再次相加,通过选择最优的相位旋转因子组合来降低信号的峰均比。另外,与分组部分传输序列算法相比,简化分组部分传输序列算法可以进一步降低寻找最优相位旋转因子组合的计算复杂度。仿真结果表明,简化分组部分传输序列算法能有效地抑制多路正交频分复用信号的峰均比且实现复杂度适中。因此,提出的降信号峰均比算法更适用于实际的多路正交频分复用系统。
The multi-channel orthogonal frequency division multiplexed (OFDM) signal is constructed of multiple OFDM signals from different frequency bands. The peak-to-average power ratio (PAPR) of the multi-channel OFDM signal is much larger than that of the single-channel OFDM signal. The PAPR reduction algorithms for the single-channel OFDM signal are difficult to apply to multi-channel OFDM systems directly. In this paper, a group PTS(G-PTS) algorithm and a simplified group PTS(SG-PTS) algorithm have been proposed. In the proposed methods, all the multi-channel OFDM signals are divided into different groups and in each group the signals are added directly. Then, the output signal of each group is further added with a different phase rotation factor. The PAPR of the signal can be reduced by selecting the optimal phase rotation factor combination. In addition, compared with the G-PTS algorithm, the computational complexity of finding the optimal phase rotation factor combination can be further reduced by the SG-PTS algorithm. Simulation results have shown that the SG-PTS algorithm can reduce the PAPR of multi-channel OFDM signals effectively, and that its implementation complexity is moderate. Thus, the proposed PAPR reduction algorithms are suitable for practical multi-channel OFDM systems.
作者
高洋
项炳龙
宫丰奎
GAO Yang;XIANG Binglong;GONG Fengkui(State Key Lab. of Integrated Service Network,Xidian Univ.,Xi’an 710071,China)
出处
《西安电子科技大学学报》
EI
CAS
CSCD
北大核心
2019年第5期128-133,共6页
Journal of Xidian University
基金
教育部联合基金(6141A02022338)
国家重点研发计划(2018YFE0100500)
国家自然科学基金(61671346)
陕西省科技计划(2019CGXNG-010)
关键词
正交频分复用
峰均比
部分传输序列
orthogonal frequency division multiplexing
peak-to-average power ratio
partial transmit sequences
