MPM-1000A Operator Manual
1000-7075 Rev E
16-1
16
APPENDIX B – RX ATTENUATOR DESCRIPTION
The M
odem‟s transmit IF power level and receiver gain are controlled based on the
following operator-configured parameters:
L-Band Transmit IF Power Level:
IF Power Level = NC Commanded EIRP
– Operator Specified Transmit Chain Gain
Factor (i.e. terminal gain from Modem output to air-interface).
The Modem has a burst-to-burst adjustable L-band transmit power range from 0 to -40
dBm.
L-Band Receive IF Gain:
The Modem receiver gain is adjusted on a burst-by-burst basis based on the anticipated
receive carrier level, which is defined by the following formula:
Mp (dBm) = 10Log (Data rate) + 10Log (T) + L
g
- 195.10 dB
In this formula,
Terminal Receiver Gain (L
g
)
– gain in dB from antenna output to Modem IF input
(including LNA/LNB gain and cable losses).
Antenna Noise Temperature (T)
– Antenna noise temperature in degrees Kelvin
(K)
Data Rate
– Data rate of desired signal in bits per second (bps)
The parameters L
g
and T are operator-specified configuration parameters for the
Modem that are entered via the MIB/HCI on the
Configure
System
page.
