【摘要】 数字移动通信近几年来得到长足的发展,而语音低码率编码是其中一项关键技术.本文提出一种脉冲自适应码本激励编码方案.该方案将规则脉冲激励算法和码本激励算法有机地相结合,采用新的有效码本结构,降低码字的维数,提高码字的效率,另外,在最佳激励搜索上采用了脉冲自适应搜索方式,避免了全寻的工作方式,使得码本搜索的计算量大大降低。通过计算机模拟结果表明,该编码方案和美国EIA公布的编码算法相比具有计算量小,所占储存空间少而合成音质几乎不下降等优点.在8Kb/s PACELP能够合成出令人满意的语音质量。而这一切又保证了PACELP算法可以在一块TMS320 C25上实现。更多还原

【Abstract】 Digital mobile is developing rapidly in recent years , while low-bit-rate speech coding is one ofkey technologies . A new pulse adaptive code-excited linear predictive coding algorithm is proposed in the pa-per . This scheme is a hybride of regular-pulse excitation and codebook excitation . And a veryeffective codebook structure is adopted in the scheme which reduces the codebook dimensions and also raises thecodebook efficiency . At the same time , pulse adaptive search procedure is used in matching the optimumexcitation sequence instead of full search procedure . All these measures make the complexity of the scheme simpleand easy to be implemented on one TMS320C25. This scheme is compared with the algorithm proposed byAmerican EIA and the results are : computational load and storage capacity were less without noticeable speechquality degradation. Computer simulation results show that at 8kb/s , PACELP can synthesize a satisfactoryspeech.更多还原