ETSI ES 202 737-2015 语音和多媒体传输质量(STQ);从用户感知的 QoS 角度对窄带 VoIP 终端(手机和耳机)的传输要求(V1.4.1)
Speech and multimedia Transmission Quality (STQ); Transmission requirements for narrowband VoIP terminals (handset and headset) from a QoS perspective as perceived by the user (V1.4.1)