Q-Flex Satellite Modem Installation and Operating Handbook
12-3
12.2 Tx Modulator Specifications
Parameter
Modem
IF Output Power Level
0 to –25dBm continuously variable in 0.1dB steps
L-band Output Power
Level
0 to –40dBm continuously variable in 0.1dB steps
Output Level Stability
±0.375dB, 0ºC to 50ºC
Transmit Filtering
Spectral roll-off factors of 5%, 10%, 15%, 20%, 25%
and 35%. See the document ‘Saving Satellite
Bandwidth by Optimising Spectral Roll-off’ (document
number AN_035) from the White Papers section of
http://www.paradisedata.com
) for more details,
including occupied bandwith calculations
Occupied Bandwidth
See referenced document AN_035 above
Recommended Channel
Spacing
See referenced document AN_035 above
Phase Accuracy
±2º maximum
Amplitude Accuracy
±0.2dB maximum
Carrier Suppression
-30dBc minimum
Output Phase Noise
As IESS-308, nominally 3dB better. Also complies with
IESS-316
IF Output Frequency
Stability
±0.05 ppm per year
L-band Output
Frequency Stability
±0.05 ppm per year
IF Harmonics
Better than –55dBc/ 4kHz in band
L-band Harmonics
Better than –55dBc/ 4kHz in band
IF Spurious
Better than –55dBc/ 4kHz in band
L-band Spurious
Better than –55dBc/ 4kHz in band
Transmit On/Off Ratio
55dB minimum
External Transmit Inhibit
By external contact closure or by TTL signal applied to
rear panel Alarms & AGC connector