Method and apparatus for recognizing modulation format of quadrature modulation signal

Abstract

Disclosed are a method and apparatus for recognizing the modulation format of a quadrature modulation signal, aiming to solve the problem in the prior art that there is a lower accuracy in recognizing the modulation format of signals. The normalized powers of a plurality of symbols in a symbol sequence of a received quadrature modulation signal are determined, the probabilities that the normalized powers of the symbols fall within each preset power range are determined to thereby determine a power distribution characteristic value of the quadrature modulation signal, and the modulation format of the quadrature modulation signal is determined according to the result of comparison between the determined power distribution characteristic value and a plurality of preset threshold values. The method described above can avoid the influence of frequency offset and phase noise on the result of recognition, and can effectively improve the accuracy in recognizing the modulation format of signals when applied to those systems with relatively larger frequency offset and phase noise, such as EON (Elastic Optical Network). 一种识别正交调制信号的调制格式的方法及装置，用以解决现有技术中识别信号的调制格式的准确性较低的问题。确定接收的正交调制信号的符号序列中多个符号各自的归一化功率，并确定该多个符号的归一化功率落在每个预设的功率范围内的概率，据此确定该正交调制信号的功率分布特征值，根据确定的功率分布特征值与预设的多个门限值的比较结果确定该正交调制信号的调制格式。上述方法可避免频偏和相位噪声对识别结果的影响，应用在诸如EON等具有较大频偏和相位噪声的系统中可有效提高识别信号调制格式的准确性。