plugged into a 2U 19" chassis. The chassis includes a redundant power supply, two backplanes
to connect to the modules, a M&C printed circuit board and at the front panel a keyboard and
display as local user interface. Each chassis can contain 10 of the optical link modules in any
combination whether they are optical transmitters or receivers.
The sat-nms LFTXRX optical link is a broadband device and transmits transparently the
complete RF spectrum from one site to the other. All modulation formats, whether they are analog
or digital, can be transmitted transparently. The RF signal is directly modulated on to a high
performance laser diode and adds no phase noise or frequency instability to the original signal.
The result is a very good signal quality.
Due to the very stable design of the optical transmitter and receiver electronics there is no need
for an Automatic Gain Control (AGC) within the circuits. So the link is compared to other vendor's
solution really transparent. Certainly a Manual Gain Control (MGC).function is included which can
be also adjusted from remote in a wide range of 31dB.
The optical L-Band transmitter module also provides LNC supply voltage including current
monitoring and RF level detection.
We tried to realize all functionality in the baseline product so that you don't have to care about
options. So LNC powering and other features are always included wherever possible. This is only
not the case in the broadband and 10MHz boards as this makes no sense here in any case and
the inductors of the LNC voltage supply would destroy low frequency performance.
For the optical interface SatService provides E2000/APC connectors from Diamond or Huber &
Suhner by default. But we are also in a position to deliver on request FC/APC or other single
mode connectors. The optical interface is located at the front panel of the 19" chassis because
the optical patch panels are most likely also at the front of a 19" rack. The connectors are slightly
shifted backwards from the normal front plane of the 19" drawer, so they neither interfere at the
front of the rack nor they can be destroyed or snapped off.
The Controller Module of the sat-nms LFTXRX is based on a separate 100x160mm printed circuit
board. It performs the following functions:
Monitor and control the optical transmitter cards LFTX
Monitor and Control the optical receiver cards LFRX
Monitor and Control the rf switch cards LFRX
Manage the redundancy switching
Control the Remote Interfaces (RS232 and LAN) The design of the monitoring & control
board is based on the same controller with integrated web server which SatService has
successfully used in all other products of the sat-nms family as well. The chip has the
following advantages:
Real Time Operation System with FTP, HTTP, SNMP over TCP/IP
Serial Interfaces
(C) 2021, SatService GmbH
www.satnms.com
LF20-UM-2107 Page 40/43
