USSD接口设计与实现。　USSD (Unstructured Supp lementary Service Data)即

非结构化补充数据业务,是一种基于GSM网络的新型

交互式数据业务,它是在GSM的短消息系统技术基础

上推出的新业务。-USSD interface design and implementation. USSD (Unstructured Supp lementary Service Data) or unstructured supplementary data services, GSM network is based on a new interactive data services, it is in the GSM short messaging system based on the technology, launched new business.