QUADRATIC METHOD IN DETECTING 4-TONES OF PUTONGHUA

分析了普通话四种声调的元音基音周期随时间变化的规律。根据对应四种声调的不同的变化曲线，利用二次分析方法建立了一个实时的四声检测差别规则，并在实践中证明了这种判别规则的实用性。

In this article,the property of Chinese 4_tones is studied.We find that the pitch_alternation in the voiced section of a Chinese word is different according to different tones.Through studying the changing curves of pitch,we build a 4_tones detecting rule which is dependent on the sex of the speaker.Quadratic analysis is used during the procedure of deducting the new rules.Experiments show that this rule can achieve an accuracy rate of 98%.