Verify Tx/Rx Path Gain Budgets
Pre-Installation Requirements
3-20
Ocean TRx™ 4500 Installation and Operations Manual
Example of Dual-Band L-Band Tx Levels calculations:
In the example, the calculation of Tx attenuation separated to two paths for two systems:
On the first path’s system (Yellow marked on the Excel) the OTRx4 system is
connected to the CCU via LMR-600 cable length of 50m. The BUX power is 16W. BUC
gain is 70 dB and the internal attenuation is 0 dB.
The Derived powers for BUC P1dB are: Input power to BUC is -28 dBm, Input power
to Pedestal is -20.2 dBm. Tx L-Band is 1200 MHz, CCU "BDMx" attenuation is "0"dB
and the “DSS” attenuation is set to -5 dB. The LMR cable Loss is -11.4 dB. As a result
of this example, the derived modem Tx L-Band Level for P1dB of BUC is:
-18.7 dBm
.
On the second path’s system (Green marked on the Excel) the OTRx4 system is
connected to the DSS via LMR-600 cable length of 100m. The BUX power is 20W. BUC
gain is 70 dB and the internal attenuation is 0 dB.
The Derived powers for BUC P1dB are: Input power to BUC is -27 dBm, Input power
to Pedestal is -19.2 dBm. Tx L-Band is 1200 MHz, CCU "BDMx" attenuation is "0"dB
and the “DSS” attenuation is set to -5 dB. The LMR cable Loss is -21.7 dB. As a result
of this example, the derived modem Tx L-Band Level for P1dB of BUC is:
-7.5 dBm.
