The ATC version of the Azdec Infra-Com cordless ultra lightweight headset provides complete mobility while maintaining two way multi-channel voice communications. The headset while retaining the infra-red transceiver is exceptionally light and comfortable to use for long periods of time.Employing digitally encoded infra-red the headset provides exceptional quality speech and allows split headset operation where the controller can communicate selectively with aircraft, telephone calls or other controllers. The system supports multiple users in either a control centre or control tower. In the control centre environment the system can be configured to provide a communications cell associated with each desk, while in a control tower multiple channels allow the free movement of many controllers throughout the .The infra-red system is not effected by radio transmissions and infra-red systems can be used in the most sensitive locations with confidence that the signals will not cause interference nor will the signal be detected outside of the area of coverage. There are no licence requirements.

The low level infra-red digital encoding eliminates ocular hazards while providing exceptional coverage with multi-channel capability. The ability to employ virtually unlimited infra-red antennas, from one base station, ensures coverage over large areas. The use of encoding similar to the international standard CCITT G.711 guarantees outstanding quality of low noise voice communications which is full duplex on each channel. Side tone is generated in the base station giving complete confidence that communication is being achieved.

Mobile operators can communicate between each other or with external communication systems. The enhanced option allows for selective communications between a mobile user and either internal or external radio communications while receiving independent communications in each ear. This enhanced option also allows for broadcast communication to be received and local two way communications to be used independently, with the two communications channels in different ears.

Interference from electrical equipment is eliminated by the use of digitally encoded infra-red, allowing two way full duplex voice communications to continue in the most arduous electrical environments. Furthermore the use of low level infra-red ensures that sensitive electronic equipment is not effected by the use of the system even when in close proximity.

The mobile operator has the options of noise attenuating, single side or ultra lightweight headset. All options are provided with a noise cancelling microphone. The mobile equipment can be fitted to most headsets allowing the utilisation of existing equipment.

Small fixed infra-red antennas receive and transmit data between mobile users and the Base Station. These antennas are connected on simple "daisy chain" wiring throughout the area of coverage. This allows for a simple low cost installation which can be readily extended to cover additional areas as required, which can be undertaken by unskilled personnel. Using the maximum number of antennas areas up to 7500 square metres (75,000 square feet) can be covered by a single system.

A belt mounted battery pack carries the operator interface controls, which are designed to be used while wearing protective clothing. These controls include the on/off switch, channel selection, volume control and press to talk button.

Although providing extensive life the battery pack can be rapidly removed and replaced with a recharged unit. A six channel conditioning battery charger is provided which can fully recharge a spent battery pack in under 2 hours.

Because of the low level of background noise of the digital electronics a regular confidence tone is provided to the mobile operator whenever in an area covered by infra-red communications. In addition, a warning tone is generated when switched to external communications.

The whole system has been designed for high reliability and availability with all MTBF calculated to the MIL-HDBK-217F Handbook.

The system has been designed to meet and has been extensively tested for both the lack of sensitivity to and the emission of electro-magnetic radiation and is capable of withstanding severe energy pulses associated with radar and similar equipment. The equipment has been independently tested for environmental conditions, shock and vibration.

Digital infra-red systems offer secure communications with a well defined area of reception, while offering the highest level of immunity to electromagnetic radiation. The system’s infra-red radiation is sufficiently low that it is classified as Class 1 to the International Standard EN 60825-1 and, therefore, exhibits no hazard.