There are a number of different variants available,
all are compliant to EMC Def Stan and Mil Std while military
versions can be compliant to Def Stan 59-41 NEMP survivability. As
transmissions are in the infra red range ship borne installations have
no difficulty passing TEMPEST requirements, a particular problem for
conventional radio systems used on bridges or operations rooms.
The main advantages of infra red communications are security and
safety. Short range infra red is virtually impossible to intercept or
jam and is not susceptible to electromagnetic interference.
The mobile user wears a headset with a belt mounted battery
pack containing the controls. Voice information is encoded within
a transceiver module mounted on the headset which is then
transmitted using infra red to an antenna. The user can freely
walk within an area covered by an antenna and have full duplex
voice communication with another user in the area or to a remote
location such as a control room. Large areas can be covered by
using multiple antennas daisy chained from a base station.
The area of coverage can be quite clearly defined as an antenna has
a very predictable coverage pattern.
The use of digital encoding ensures that the infra red power being
transmitted is very low with the system being given a Class 1 LED
product designation and posing no health hazard to users.