The invention relates to a
speech enhancement method of a
microphone array under a non-
stationary noise environment. The probability of an effective
signal is accurately judged by means of phase information between passageways in order to improve non-
stationary noise environment interference resistant performance. The method which estimates the probability of the effective
signal specifically comprises the following steps: (51) according to a required beam width, calculating a threshold T1=NL sin (theta) / Fs, wherein N represents frame length, L represents
microphone unit distance, theta represents beam width, and Fs represents sample frequency, (52) calculating the valve of the sum of phase differences
omega of input signals of all passageways on all frequency points pd (n,
omega); and (53) when the pd (n,
omega)>omega (M-1) T1, the effective
signal probability exists on the frequency point p1 (n, omega)=1, otherwise, p1 (n, omega)=0, wherein M represents the number of microphones. Due to the fact that the phase information between the passageways is used, judgment to the probability of the effective signal is enabled to be more accurate, the
signal to noise ratio of picked up voice is improved, whole performance is improved, and particularly non-
stationary noise environment interference resistant performance is improved.