Page168 of 544 Transmissionparameters
553-3011-100 Standard14.00 January 2002
Idle Channel Noise
Idle channel noise is noise in the absence of a signal. It is the short-term
average absolute noise power, measured with either C-message weighting for
µ−Law or Psophometric weighting for a A-Law. The 3 k Hz flat measurement
uses equal weighting for all frequencies in the 20-3000 Hz range. The values
are shown in Table45.
Table 4 4
Transhybrid loss
Input Frequency (Hz) Transhybrid Return Loss (dB)
300 16
500 20
2500 20
3400 16
Table 4 5
Idle Channel Noise
Connection µ-Law C Message
Noise dBrnC0
A-Law Psophometric
dBmP0
3 kHz
dBm0
Line — Line <20 >65 <29
Line — Trun k <20 >65 <29
Trunk — Trunk <20 >65 <29