User guide

Appendix C - Dynamic Power Control C-3
Description
Description
Operation of the DPC algorithm is controlled by the parameters shown in
table C-1, below.
The start point for all enabled modulators is the Nominal Power Level. This
level is measured during initial system turn-up and is the power level at which
all modems will initially transmit when a call is established. Once communica-
Table C-1 Dynamic Power Control Parameters
Parameter Default Significance
Nominal Power
Level
-25 (IF)
-40 (L-Band)
dBm
Power used for scaling Maximum power after
switching
Calibrated Data
Rate
System
Specific
Data Rate which is used for scaling Maximum power
after switching
Maximum Power
Level
System
Specific
Maximum transmit power level permitted based on
link/satellite parameters
Minimum Power
Level
System
Specific
Minimum transmit power level permitted based on
link/satellite parameters
BaseLine Power
Level
-25 (IF)
-40 (L-Band)
dBm
Function of the power given to the modem by the
VMS for the last switch command based on link
budget calculations
DPC Offset 0 dB Power adjustment to account for changes in the
environment (rain fade) or other factors in order to
maintain link connectivity
SOTM Offset 0 dB Power adjustment received from ROSS based on
current location of modem within the satellite
footprint
Target Eb/No 10 dB Target E
b
/N
o
value for which DPC is aiming
Target Range 0.2 dB Target range for no power adjustment; No adjustment
occurs when power is within this range
Speed Up
Eb/No
5 dB DPC and PLDM process speeded up from default (1/
min) if E
b
/N
o
is below this amount
Target DPC
Address
0.0.0.0 Identifies the modem that is transmitting to this
device and will receive Eb/No values