本欧洲电信标准（ETS）给出了在增强全速率语音业务信道上不连续传输（DTX）期间，移动台（MSs）和基站系统（BSS）中背景噪声评估、噪声参数编码/解码和舒适性噪声产生的详细要求。本ETS中描述的要求对于所有能够支持增强全速率语音通信信道的GSM移动台的实施是强制性的。在所有能够支持增强全速率语音业务信道的GSM BSS中，接收机要求是强制性的，发射机要求仅适用于将使用下行链路DTX的情况。

This European Telecommunication Standard (ETS) gives the detailed requirements for the correct operation of the background acoustic noise evaluation, noise parameter encoding/decoding and comfort noise generation in Mobile Stations (MSs) and Base Station Systems (BSSs) during Discontinuous Transmission (DTX) on enhanced full rate speech traffic channels. The requirements described in this ETS are mandatory for implementation in all GSM MSs capable of supporting the enhanced full rate speech traffic channel. The receiver requirements are mandatory for implementation in all GSM BSSs capable of supporting the enhanced full rate speech traffic channel, the transmitter requirements only for those where downlink DTX will be used.