Application of group delay spectrum parameters in mandarin digit speech recognition

The high confusion between Chinese digits directly affects the performance of Chinese digit speech recognition. Traditional methods are difficult to make an effective distinction between easy-confused digits. This paper presents a multi-parameter and multi-level recognition strategy. Firstly the digits are recognized by Mel spectral parameters based on HMM, then take secondary classification for the easy-confused digits using RRCGD-CC(Reflected Roots Chirp Group Delay-Cepstral Coefficients), which is a new parameter based on group delay spectrum, and SVM. The experimental results show that the recognition rate of“2”and”8” is improved by 8%, and the recognition rate of the system is improved by 2.3%. This result is fully explained that the RRCGD-CC is valid for easily confused digits.