Indoor Radio Communication Enhancement System for Changi International Airport

In 1988, the Changi Airport Authority of Singapore (CAAS) called for a tender to design, manufacture, supply, delivery, installation, testing and commissioning of an indoor radio communication enhancement system for their new Singapore Changi Airport Terminal 2.

Omni Tronics proposed an advanced type of total in-building coverage for all the radio systems to be used at the airport. This project was successfully executed and handed over to CAAS in time for the opening of the airport in 1989

We were the first in the world to implement a system that combined a 30-channel trunking system as well as to implement an in-building system for 32-paging channels using frequencies from 148-174 MHz.

The in-building radio system consisted of:

    1. System A : 32 public VHF paging channels;
    2. System B1 : 15 UHF repeaters network;
    3. System B2 : 7 UHF high-powered repeater system for public safety; and
    4. System C 30 (800 MHz.) Trunked Repeater Network for airlines, freight forwarders etc. .

System A served to enhance the tone and alphanumeric radio paging services operating in the band 138-174 MHz. in the basement of Terminal 2.

This system receives paging call signals via the base antenna which were directed towards the paging base stations located at the Changi Exchange. The off-the-air paging signals are first filtered through specially tuned cavities filters and allowed only the 32 paging frequencies to propagate along the transmission lines. The weak signals are then amplified and re-propagated to paging receivers in the service areas at Terminal 2's basement level.

System B served to enhance the existing two-way radio repeater services in Terminal 2, which CAAS had provided for airport operators to command and control their ground movement operations.

This system functions as a continuous two-way radio transmission link between the portables operating inside Terminal 2 and the repeater base stations located outside Terminal 2.

System B1 : 420-430 MHz. band for a 20-channel repeater network.
System B2: 450-460 MHz. band for a 8-channel repeater network.

System C served to enhance the coverage of the Trunked Radio Service which operates in the 810-860 MHz. band inside Terminals 1 and 2.

The outdoor antenna system provides an omni-directional coverage of up to 4km for portables operating outside Terminal 2. The indoor cable and antenna system provided field coverage for portables operating in Terminals 1 and 2.