Infra Red Basestation interfaces between the analogue circuits and the simple serial bus and in addition provides the power supply unit of the Infra Red voice communications system.

Small enough to be mounted in any convenient location, the baseline unit shown measures nominally only 300 by 300 mm. Within the basestation is the interface for the analogue voice circuits and control electronics for the digital antennas, as well as the power supply for the basestation and antennas. All cables are connected by glands on the bottom of the unit which ensures the environmental integrity of the enclosure. To ensure high availability the basestation has been specifically designed so that it can be replaced in a very short period of time.

The basestation has been designed to allow the use on the wide variations of voltages which can be encountered on power supplies. The Basestation power supply provides antennas with stabilised and filtered power to ensure reliable operation, immunity to conducted noise, and long cable runs.

Indication is provided for "Power On", confirmation that the base station is functioning "Base Transmitting" and indication that a mobile operator is using the system "Mobile Transmitting". In addition on enhanced base stations indication is also provided when external communications have been selected.

Both internal and external mobile users can use the same base station with only the operators with the enhanced equipment having access to the external communications.

The owner can select various options for input and output analogue voltage levels and has a choice of different terminating impedances which are selected at the base station. All analogue interfaces are isolated from ground.

It is also possible to co-locate two systems with each systems antennas in the same area. This is achieved by connecting a simple control cable between the two base stations and nominating one base station as the "master". This allows two totally independent systems to be used within the same infra red environment.