Development of the DLR "Smartsound" noise adaptive public address control system

The Docklands Light Railway (DLR) is a light rail rapid passenger transit system which serves the needs of residents and businesses within the London Docklands regeneration zone. DLR has a policy on noise which states the intentions of the company for the system-wide control of noise arising from train operations and sets down target maximum noise levels at adjacent buildings. In locations where the target levels are exceeded, DLR is committed to using best practicable means to minimise the levels of exterior noise at source. The "Smartsound" noise adaptive public address (PA) control system was first developed out of a need to resolve specific problems connected either with the inadequate transmission of announcements to passengers on stations during periods of intrusive background noise, or with unwanted overspill of the PA sound into neighbouring properties. The success of "Smartsound" has resulted in the development of a new control of environmental noise pollution whilst enabling the railway to maintain not only good communication with its passengers but also enhancement of customer safety and assurance through intelligible announcements when it matters most.