ETSI EN 301 437-1999 终端设备(TE).对支持话音电话业务并与模拟公用交换电话网(PSTNs)连接进行泛欧认可的TE的附加要求,其中网络寻址通过双音多频(DTMF)信令(若有)实现
Terminal Equipment (TE); Attachment Requirements for Pan-European Approval for Connection to the Analogue Public Switched Telephone Networks (PSTNs) of TE Supporting the Voice Telephony Service in Which Network Addressing, if Provided, is by Means of Dual