为降低正交频分复用(OFDM)信号的峰均功率比,提出了改进的星座图扩展方法。改进的算法采用压缩扩张变换方法的部分概念,在不减小星座点间欧氏距离的约束条件下,动态地向外扩展传输数据的星座点,从而降低OFDM信号的峰均功率比。该方法在接收机端不需要任何的处理过程,而且没有边带信息。改进的星座图扩展方法能够取得的峰均功率比比原来方法的低约1 dB,而且简单实用。 In order to reduce the PAPR of Orthogonal Frequency Division Multiplexing (OFDM) signals, an improved constellation expansion method is proposed. The improved algorithm adopts the concept of compression-expansion transform, and dynamically expands the constellation points of the transmitted data without any reduction of the Euclidean distance between the constellation points, so as to reduce the peak-to-average power ratio of the OFDM signal. This method does not require any processing at the receiver and does not have sideband information. The improved constellation expansion method can achieve a peak-to-average power ratio about 1 dB lower than the original method, and is simple and practical.