December 2007

Technology Overview

Use Communication Technologies to:

Perform dispatching instructions and transmit schedule adjustments.
Provide emergency and incident response.
Enable route deviation and dynamic rerouting.
Facilitate communication between the bus operators and dispatchers, supervisors, or other transit staff necessary for fixed route bus operations.

Two buses, side-by-side, in street traffic.

Communications technologies facilitate interaction between drivers, dispatchers, emergency response and other personnel involved in transit and transportation operations. A comprehensive system that combines various communication technologies, including those that transmit voice, text, data, and video, will allow seamless communication among all personnel, vehicles, facilities, and data systems, and often across modes. Digital radio, cellular and other wireless networks may be utilized to transmit data in addition to voice. Pre-programmed text messages, that minimize voice traffic over the radio network, can be sent between drivers and dispatchers using a range of devices. Mobile data terminals (MDTs) provide two-way text based communication and the ability to upload data collected during a bus run.

Large fixed route bus transit agencies (those operating 100 or more buses) often install both voice and text communication devices. The use of MDTs for standard communication purposes minimizes reliance on voice-based communication in large, urban areas where bandwidth is often scarce. Voice communication is still used in cases when pre-programmed MDTs messages are insufficient. However, a voice-only network is usually sufficient for the communication needs of most small fixed route bus transit agencies (those operating fewer than 100 buses).