Comtech EF Data SNM-1001L - Manual (Page 323)

SNM-1001L Satellite Modem Revision 1
Burst Mode Modulator Operation MN/SNM1001L.OM
C–9
C.4.4 Differential Decoder
The differential decoder is not needed as the data inversion ambiguity is resolved during
acquisition.
C.4.5 Demodulator Spectrum Rotation
The operator can select normal or inverted spectrum for the Demodulator Input.
C.4.6 Receive Frequency (IF)
The range of the input IF spectrum can be selected by the operator from 950 to 1750 MHz, in 1
Hz steps.
The actual value of offset from the programmed frequency is available to the operator on the
front panel as well as the remote port. The resolution of this value is 1 Hz. Monitor accuracy is
± 10 PPM.
C.4.7 Receive Input Power (Desired Carrier)
The modem can meet the specified BER and automatically adjust to a receive IF input power of
–30 to –55 dBm. Monitor accuracy is
± 2.5 dB.
C.4.8 Receive Input Power (Composite)
The modem can operate to its specified performance under all the following conditions:
• The sum of all carriers is ≤ -5 dBm.
• The sum of all carriers within 10 MHz from the desired is ≤ +30 dBc.
• The sum of all carriers is ≤ +40 dBc.
C.4.9 IF Input Overload
The modem will not be damaged by a continuous receive IF input of +20 dBm.
C.4.10 Demodulator IF Input Shape
The modem can be set to match any of the following spectral mask specifications.
• INTELSAT/EUTELSAT
• Closed net (Comtech EF Data)