While the fibre optical links where designed by SatService GmbH mainly for the transmission of the satellite L-Band frequency band (950 to 2150MHz) also a broadband version from 50MHz to 2150MHz is available. So this link type can also be used to transmit the traditional 70 or 140MHz IF bands of satellite ground stations and a microwave link. But also other terrestrial applications are feasible like the transmission of GSM signals in the 800 and 1800MHz frequency bands.
As a unique feature the sat-nms LFTX/RX modules can transmit L-Band and 10MHz signals together on one single fibre connection. This is a growing application for VSAT and satellite ground station transmit chains which make use of Block Up-Converter (BUC). These BUCs very often need a 10MHz reference frequency signal for their internal local oscillators. This is generated within the satellite modem and also transmitted via the coaxial L-Band output.
By using the LFRX-10/LFTX-10 link, it is not possible to monitor or to adjust the level of the 10Mhz signal with the internal adjustable attenuator. If you have to do so, or if you want to set up a 10MHz only link, sat-nms LFRXO10/LFTXO10 Version is the right choice. It provides internal attenuation function as well as signal level measurement for your 10MHz signal.
The sat-nms LFTX/RX fibre optical link can transmit this combined/multiplexed frequency signals. Each fibre optical link (FOL) consists of two destinations which are interconnected via a fibre optical cable. On one side of the link is the optical transmitter and on the other side is the optical receiver. Both modules are Euro card sized (100x160mm) printed circuit boards which are 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 LFTX/RX 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 30dB.
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.