RFX144V24-S23 and RFX96V24-S23 Modem Designer’s Guide
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1070
No. 57
Voice/Audio VOX A0 Filter Coefficient
The VOX energy averaging filter coefficient A0 is a function of the filter time constant.
Format:
16 bits, signed, twos complement
Equation:
A0 = 917.5/x
Where:
x = VOX turn-off time constant in seconds.
Default Value:
03A8h (0.98 sec.)
No. 58
Voice/Audio VOX A1 Filter Coefficient
The VOX energy averaging filter coefficient A1 is a function of the filter coefficient A0.
Format:
16 bits, signed, twos complement
Equation:
A1 = 7FFFh - A0
Where:
A0 = VOX energy averaging filter coefficient.
Default Value:
7C57h
No. 59
Voice/Audio Energy AGC Reference Level
Energy reference level for the Energy AGC. The default value is loaded each time the modem is configured to Voice Codec
Mode (CONF = 90h or 98h), or Audio Codec Mode (CONF = 92h or 94h).
Format:
16 bits, signed, twos complement
Equation:
Level = (10[x/20])(23315)
Where:
x = AGC energy reference level in dBm.
Default Value:
0380h (-28.31 dBm)
No. 60
Voice/Audio Energy AGC Slew Rate
Slew rate for the Energy AGC. The slew rate controls how rapidly the AGC will adapt the average message energy to the
AGC reference level. Larger/smaller slew rate values correspond to faster/slower average energy convergence to AGC
reference level. The default value is loaded each time the modem is configured to Voice Codec Mode (CONF = 90h or 98h)
or Audio Codec Mode (CONF = 92h or 94h).
Format:
16 bits, signed, twos complement
Default Value:
3C00h
No. 61
Voice/Audio Energy AGC Gain Adaptation Threshold
If the energy of the message being encoded exceeds the AGC gain adaptation threshold then the encoder AGC gain will be
increased/decreased when the average energy is less/greater than the AGC reference level. The AGC gain adaptation
threshold should be greater than the Voice Mode VOX turn-on threshold whenever the Energy AGC is not disabled and bit
DCVOX is zero. The default value is loaded each time the modem is configured to Voice Codec Mode (CONF = 90h or 98h)
or Audio Codec Mode (CONF = 92h or 94h).
Format:
16 bits, signed, twos complement
Equation:
Threshold = (10[x/20])(23315)
Where:
x = AGC gain adaptation threshold in dBm.
Default Value:
00A3h (-43.11 dBm)
Summary of Contents for RFX144V24-S23
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