基于多相互补序列的多载波信号的峰值因子分析

Analysis of crest factor of multicarrier signals based on polyphase complementary sequences

针对具有相同幅度和等频率间隔的许多余弦函数组成的多载波信号,本文首先对它们的峰值因子上界进行了推导,得出它取决于由多载波信号初始相位组成的复序列的幅度谱.然后证明了由多相互补序列对中任一互补序列构成的多载波信号的峰值因子小于或等于6dB.最后,给出了由长度等于10的多相互补序列构成的多载波信号的两个仿真例子,结果表明它们的峰值因子在5～6dB之间,和理论分析相吻合.此外,还发现二进制Golay互补序列能够产生对称的多载波信号,该特性对于某些应用是很有用的.

For the multicarrier signals consisting of a number of cosine functions with equal amplitudes and equally spaced frequencies, their upper bound on crest factor, which depends on the amplitude spectrum of a complex series formed from the initial phases of a multicarrier signal is derived. It is also proved that the crest factor of the multicarrier signals, constructed of any one polyphase complementary sequence of a polyphase complementary sequence pair, is less or equal to 6dB. Finally, two simulation examples of the multicarrier signals constructured of the polyphase complementary sequences with length 10 are given. Simulation results indicate that their crest factors are between 5 and 6 dB, in agreement with theoretic analysis. It is also found that symmetric multicarrier signals can be produced with Golay complementary sequences. This is useful for some applications.