Comtech X-Band Low-Noise Block Down Converter (LNB) Series
Comtech's X-Band Low-Noise Block Down Converter Series (LNB) meets or exceeds system requirements for commercial and military
geosynchronous satellites worldwide. Their compact design and rugged construction make them ideal for transportable applications and
severe environments. They have a comprehensive set of options to accommodate systems ranging from Very Small Amplifier Terminal
(VSATs) to major earth stations. The X-Band LNB allows for interfacing, at the antenna, with our LPOD family of X-Band outdoor BUCs
for sourcing of the LNB bias voltage and high stability reference in either single or redundant configurations.
The amplifiers incorporate both HEMT devices for low-noise temperature performance and GaAs FET devices for low intermodulation.
The units use surface mounted components for robotic manufacturing techniques, thereby ensuring maximum product consistency and
enhanced reliability. The X-Band LNB includes integrated filtering to address adjacent power issues peculiar to demanding X-Band
The amplifier series utilizes proprietary circuitry and high-quality components to achieve an MTBF in excess of 160,000 hours. Each unit
is subjected to a 72-hour burn-in and temperature cycled from -40 to 140°F (-40 to +60°C).
The LNBs are housed in waterproof enclosures with small profiles to better accommodate redundancy configurations. The enclosures
also provide a pressurizable, integral waveguide flange.
Transmit reject filters, cables and other integration materials are offered as required.
1+1 (one backup for one primary) and 1+2 (one backup for two primary) redundant LNB systems are available, complete with mounting
plate, brackets and indoor redundancy controller/power supply. Transmit reject filters, cables and other integration materials are offered
1:1 Redundant LNB System Block Diagram
Input Frequency Range
7.25 to 7.75 GHz
Output Frequency Range
950 to 1450 MHz
40, 45 K
50, 60 dB
Stability (Over Temp. & Frequency)
± 1.5 dB over Full Band typical
0.50 dB p-p over 40 MHz typical
Level @ 1 dB Comp.
+10 dBm, (15 dBm opt.)
Third Order Intercept
+20 dBm (+25 dBm opt.)
0.1°/dB @ 0dBm
De-sense level (transmit reject)
-25 dBm min.
-65 dBc @ 0 dBm
Linear Group Delay
± .05 ns/MHz
Parabolic Group Delay
± .005 ns/MHz²
± 1 ns p-p
Output Return Loss
15 dB minimum
External Reference Input
10 MHz 0 ± 5 dBm at input
Phase Noise (offset)
+12 to +24 VDC @ 500 mA
Environmental and Physical
-40 to 140°F, (-40 to +60°C)
-50° to +71°C (58° to 160°F)
100% with condensation
10,000 ft above sea level
Dimensions (H x W x D)
1.9” x 3.2” x 6.9”
< 2 lbs
Coaxial, ITT KPT02A8-4P Male or
ITT MS3112E10-6P Male