Evaluation of Mobile Surveillance and Wireless Communication Systems Field Operational Test

From June 1994 through September 1998, the California Department of Transportation and FHWA conducted a field operational test (FOT) to evaluate the benefits a mobile surveillance and wireless communication system provides in support of freeway surveillance, ramp metering, and arterial traffic management. Six surveillance and three ramp meter trailers were designed and built for deployment in areas where permanent detectors, electrical power, and landline communications are not available. A retransmission or relay site and data reception equipment for use at traffic management centers and research facilities also were installed. The major components of the surveillance and wireless communication system are black-and-white cameras that supply imagery and data to video image processors; color pan, tilt, and zoom surveillance cameras; narrow and wideband spread spectrum radios; 170 controllers; video compressors; and a trailer-based power distribution system. An independent evaluation of the FOT was conducted in accordance with FHWA guidelines. The FOT showed that the trailers could be effective aids to traffic management when site survey and selection guidelines developed during the FOT are followed and trailer maintenance is performed. At the trailer locations used in the tests, the measured traffic flow parameters and compressed video imagery were able to provide local-responsive ramp metering onto a freeway main line during periods of heavy traffic and video imagery that facilitated control of arterial traffic signals. Data were effectively shared among state and city traffic management centers and university research facilities over spread spectrum radio links.