RAD Multiplexers Transmit Critical Radar Traffic Between Two Major UK Airports

Megaplex-2100 incorporates cross-site PBX traffic without leasing additional expensive E1 lines

When Peel Airports Group, the owners of England’s Liverpool John Lennon Airport and Yorkshire's Robin Hood Airport Doncaster Sheffield decided to upgrade the radar and communication services due to a programmed airspace change, they turned to Cyrrus Ltd., a leading British independent consultancy that focuses on bringing creative, imaginative solutions to the challenges facing the airport and air traffic industries.

The main en-route air traffic control service provider in the United Kingdom, NATS, based at Swanwick or Manchester, hands over control of aircraft inbound into Robin Hood Doncaster to the approach control unit of the destination airport when it is about 40 nautical miles away. In this case, Liverpool John Lennon Airport – despite being located nowhere near the aircraft’s destination – supplies the approach control service to Robin Hood Airport using critical radar and related time-sensitive data transmitted over a dedicated Wide Area Network (WAN) that runs some 80 miles between the two locations over two E1 leased lines. This process realizes significant savings in infrastructure and manning overheads without any detriment to safety.

Having determined the technical requirement and created the system design, Cyrrus approached Cambridgeshire-based Magdalene Ltd., an authorized RAD Data Communications partner, for a solution to meet the operational requirement. Magdalene recommended that RAD’s Megaplex-2100 multiservice access multiplexers be deployed at each end of each E1 line. In addition, at John Lennon Airport, RAD’s ASMi-52 G.SHDSL modems are used to transport traffic over a copper line between old and new control tower buildings. Magdalene utilized its marshalling, integration and test-bed facilities to build and configure the products prior to site deployment, and were also on hand to assist Cyrrus in commissioning the solution.

Complex Applications Accommodated by Network Architecture
Apart from radar hardware changes, the project also entailed frequency allocation alterations together with new air traffic control operational procedures. Among the many complex applications that have to be accommodated by the architecture are full redundant path switchover, G.703 co-directional 64 kbps channels, PCM voice, radar data, and Ethernet status monitoring, all of which have to be transported across a fault tolerant WAN network.