The experiments show combination features can effectively improve the system performance. 2).Combinations of pitch and LPCC, PLPCC, PL_MFCC or MFCC can further improve ASR system accuracy.

• 研究 PL_MFCC、PLPCC、MFCC、LPCC及其一阶差分的性能，并研究动静态组合特征参数的抗噪性能；