Iridium Repeaters – Frequently Asked Questions
Global Foxcom’s Iridium Repeater systems are used to extend signals into any space where it is not possible to operate Iridium handsets or modems.
Typical situations include, but are not limited to:
- Control rooms
- Operation centres
- Bunkers (civil & military)
- Hangars
- Universities
- Research labs
Iridium signals are within the range 1616 to 1626.5 MHz.
There are two outdoor antennas; one for transmit (uplink) and another for receive (downlink).
Antennas are passive, i.e. no built-in low noise amplifier (LNA), so signal loss through attenuation on the cables has to be limited to 1.5dB.
Max cable length is 5 meters using LMR400; this can be extended slightly by using cable with a lower attenuation factor.
Similarly, there are two indoor antennas.
As standard, the indoor antenna cables are 20m long LMR240.
This can be increased to 40m by upgrading to LMR400.
When using an optical repeater, the distance between outdoor antennas and indoor antennas can be up to 3Km.
For smaller buildings, where there is a shorter distance between indoor and outdoor antennas, there is a coaxial repeater that doesn’t have an optical link.
More details are here – the optical repeater system is illustrated in Option 1, and the coaxial repeater in Option 2.
An optical repeater system can cover a distance of 3km between outdoor and indoor antennas.
For smaller buildings, where the distance between indoor and outdoor antennas is less than ~40 meters, a coaxial repeater is a good option.
