Radiocommunications are playing a pivotal role as London’s bus fleet grows by 40% to 8,000 vehicles.
London Buses’ existing voice radio communications system had been in place since the early 1970s providing communications with depots and central control. Enhancing the old network to meet new challenges was nearly impossible.
ATDI were contracted by Tait Communications to help bring the system into the 21st century. In the new system, less time critical data will use GPRS technology with backup data capability from a voice system. The voice system will also support emergency working.
The new voice network, like its predecessor, is based on the MPT 1327 standard. This uses modern switching technology to reduce call loss. To ensure that the new system provides coverage of all the London bus routes and support all anticipated traffic levels, ATDI undertook extensive network simulation and modelling.
As ATDI Principal Engineer, Nick Kirkman comments, “The decision as to whether a mobile should hunt for a new base station or stick on that to which it is currently registered materially affects the ability of each base station to support its intended traffic. Parameters like this needed to be explored to ensure that the network design would comply with London Buses’ detailed coverage and traffic requirements.”
One of the key difficulties with such a large fleet in such a confined space was the sheer amount of simulation data. Several ATDI modelling activities generated millions of discrete pieces of data as buses moved across the capital, each piece forming part of the overall story. ATDI employed ICS Telecom modelling software to complete the work.
Phil Manley, Project Manager at Tait, says: “The new network meets all of London Buses’ requirements and forms an ideal platform for future expansion. The ATDI activity was key to getting the system dimensioning just right.”