UMTS标准演进的情况介绍. (2003-07-10 16:36:22). UMTS系统的标准经过多年发展，已 趋于成熟，其标准化工作由3GPP组织完成，到目前主要有四个版本，即R99、R4、R5和R6。 R99网络. 从系统角度来看，R99系统仍然采用分组域和电路域分别承载与处理的方式， -evolution of the UMTS standard briefing. (2003-07-10 16:36:22). UMTS system standards after years of de

09年发布，v9.0.0已出，但3gpp网页出现错误，无法下载-Digital cellular telecommunications system (Phase 2+) Universal Mobile Telecommunications System (UMTS) LTE Global text telephony (GTT) Stage 1: Service descr iption (3GPP TS 22.226 version 8.0.0 Release

This class provides methods to play DTMF tones (ITU-T Recommendation Q.23), call supervisory tones (3GPP TS 22.001, CEPT) and proprietary tones (3GPP TS 31.111). Depending on call state and routing options, tones are mixed to the downlink audio or ou