数据卡作为基于HSDPA技术的终端设备，可以在3G网络覆盖的任意地方接入Internet，是移动通信和互联网技术的完美结合。传统的数据卡语音功能方案存在语音质量低、制造成本高等问题，因此，对HSDPA数据卡语音功能优化的研究具有一定的现实意义。 传统的数据卡语音功能方案，在数据卡侧添加了语音采集模块，相应的在数据卡侧增加了语音专用接口和专用耳机，并相应增加了语音专用接口和专用耳机，增加了数据卡的制造成本，同时语音质量也存在一定的问题。本文分析了HSDPA标准以及USB传输协议的基本原理和技术特点，研究了数据卡语音功能的实现方法。针对语音质量下降和制造成本过高的问题，本文提出了一种优化方案。具体的工作包括以下几点： (1) 简化了传统数据卡的硬件架构方案，去掉了单板上的专用耳机接口，直接利用PC端的语音采集模块，通过USB接口与数据卡进行交互，语音的播放也直接可以利用PC侧现有的资源；(2) 在研究USB接口协议的基础上，设计了一个传输语音数据的专用端口DIAG口，承担数据卡与PC间数据的交互，通过PCUI口下发和回复AT命令。根据PCM语音格式以及传输速度，设计了语音数据传输过程中的函数；(3) 针对语音帧丢失引起的语音失真，设计了语音帧丢失补偿算法。 PEAQ测试及相应的MATLAB仿真结果表明，该方案在减少硬件添加和节约制造成本的基础上，实现了数据卡的语音通话功能，有效地提高了语音的传输质量，具有较好的应用前景。

As a kind of HSDPA technology terminal equipment, data-card can access Internet conveniently where the Third Generation network (3G) is covered, and it’s a perfect immergence of mobile communication and Internet technology. The traditional data-card has the disadvantages of high expense and awful voice quality, so the research for optimizing voice performance is much useful. The traditional design sheme of data-card adds voice sampling module and correspondingly dedicated earphone and earphone interface. In hence, data-card expence is higher, and voice quality is weaker. In this paper, the recommendations of HSDPA and USB are introduced, but the basic data-card design scheme is explained. On the basis of this, an optimization scheme is submitted. My research emphasizes on the following contents: (1) Simplify traditional data-card construction scheme, and discard dedicated earphone interface for veneer; directly use PC voice sampling module, and exchange data with data-card through USB interface; (2) Research interface agreement of USB, and a dedicated voice data transfer interface – DIAG is designed. Through this scheme, PCUI interface is used to download and upload AT order. According to PCM voice frame structure and transfer velocity, all kinds of transfer functions are designed; (3) On account of voice frame discard leading to serious voice distortion, compensation for discard frame algorithm is contrived. PEAK tests and corresponding MATLAB simulation results hold that our designed data-card can realize and improve voice transfer performance, on the basis of simplifying hardware structure and save costs.