A. frequency translations – Comtech EF Data MIDAS Version 4.X NMS Configuration User Manual
Page 133
MIDAS 4.X NMS Configuration Rev. 6
Frequency
Translations
A-1
A
A
A
p
pp
p
pp
e
ee
n
nn
d
dd
i
ii
x
xx
A
A
A
.
..
F
FF
r
rr
e
ee
q
u
uu
e
ee
n
nn
c
cc
y
yy
T
T
T
r
rr
a
aa
n
nn
s
ss
l
ll
a
aa
t
tt
i
ii
o
oo
n
nn
s
ss
Ku-Band Frequency
Translations
The following parameters are configurable for Ku-Band:
Satellite – Uplink Factor
Equivalent to Downlink Factor Added to Translation.
Satellite - Downlink Factor
Equivalent to LNB LO (Low Noise Block Converter Local Oscillator
frequency).
Common Ku-Band LO’s include 10.0 GHz, 10.75 GHz, and 11.3 GHz.
Satellite - Translation
Frequency difference between the Transponder TX Center and the
Transponder RX Center (Ku-Band Default = 2.300 GHz).
Satellite - Hi Side Injection
Hi Side Injection is where the LNB LO frequency is higher than the
RX RF frequency and the difference is used to convert to L-Band.
Low Side Injection is where the LNB LO frequency is lower than the
RX RF frequency and the difference is used to convert to L-Band (Ku-
Band default = OFF/Low side injection).
Transponder - TX Center
TX center frequency the Ku transponder.
Transponder - RX Center
RX center frequency the Ku transponder.
This example shows a 36 MHz Ku-Band transponder with the default case of low side
injection, which results in no frequency inversion. If high side injection is specified, use
the C-Band example, substituting Ku-Band frequencies in the examples. Figure A-1
shows the relationship between the downlink RF frequencies and the corresponding
L-Band IF frequencies for the first transponder of a satellite.
Note: There is a 2 MHz guard band at the lower and upper edges of the transponder, so
the Ku- and L-Band display 40 MHz of bandwidth (FC
± 20 MHz).