Determining The 1 Db Compression Point; Figure 50. Adjusting Transmit Power Using Isite And Web Isite - iDirect evolution x1 Installation Manual

15.2 Determining the 1 dB Compression Point

Perform the 1 dB Compression Point test using the same CW carrier used during the cross
polarization test. This test determines the point at which the Satellite Router's transmit
power saturates the BUC.
If using iSite, perform this procedure in the Adjust Transmit Power section of the Cross
Polarization dialog box. If using Web iSite, perform this procedure in the Transmit Power
section of the Cross Polarization page. Both options are shown in
WARNING!
To avoid over driving the satellite, the BUC and antenna must be sized
correctly for the network.
To Determine the 1 dB Compression Point:
1. With the access controller observing the transmitted CW signal, increase the Transmit
Power in iSite or Web iSite by 1 dBm.
WARNING!
Although this is unusual, it can occur. Reduce power and try again.
2. If a 1 dB increase in power is observed, increase the Transmit Power by another 1 dBm.
3. Repeat Step 2
4. Subtract the observed power increase from 1. For example, if power increased by 0.8 dB,
the difference is 0.2 dB. Record the difference as "delta."
5. Increase the Transmit Power by 1 dBm. Confirm that the observed power increase is again
less than 1 dB from the previous value. Add the difference from 1 to the delta recorded in
Step 4.
6. Repeat Step 5
7. Record the Transmit Power setting of the Satellite Router at the point at which delta
equals 1. This is the 1 dB compression point. The Network Operator will enter this value
later as the Maximum Power for the remote site in iBuilder.
iDirect Satellite Router Installation and Commissioning Guide
iDX Release 3.3

Figure 50. Adjusting Transmit Power using iSite and Web iSite

If no power increase is observed, the BUC may already be saturated.
until the observed power increase is less than 1 dB.
until the sum of all differences (delta) is equal to 1.
Determining the 1 dB Compression Point
Figure 50.
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