03.503GPPTransmission planning aspects of the speech service in the GSM Public Land Mobile Network (PLMN) systemTS
The maximum noise level produced by the apparatus at the UPCMI under silent conditions in the sending direction shall not exceed‑64 dBm0p.
NOTE 1: This level includes the eventual noise contribution of an acoustic echo canceller under the condition that no signal is received.
NOTE 2: This figure applies to the wideband noise signal. It is recommended that the level of single frequency disturbances should be 10 dB lower (ITU‑T Recommendation P.11).
Compliance shall be checked by the test described in annex C, clause C.2.1.
The maximum (acoustic) noise level at the handset and headset MS when no signal (O‑level) is received from the speech transcoder shall be as follows:
– if no user‑controlled receiving volume control is provided, or, if it is provided, at the setting of the user‑controlled receiving volume control at which the RLR is equal to the nominal value, the noise measured at the ERP contributed by the receiving equipment alone shall not exceed –57 dBPa(A) when driven by a PCM signal corresponding to the decoder output value number 1;
– where a volume control is provided, the measured noise shall also not exceed –54 dBPa(A) at the maximum setting of the volume control.
NOTE: In a connection with the PSTN, noise conditions as described in ITU‑T Recommendation G.103 can be expected at the input (POI) of the PLMN. The characteristics of this noise may be influenced by the speech transcoding process (for further study).
Compliance shall be checked by the test described in annex C, clause C.2.2.