Monitoring, Telemetry, and Control for Rapid Transit

The San Francisco Bay Area Rapid Transit District is building a new rapid transit system on which trains will operate automatically. Multipurpose channels and terminals will be used to monitor and control train operation, electrification, and support facilities. Incoming data and events are to be transmitted and processed digitally. System supervisory control signals, whether incoming or outgoing, will be transmitted in a binary coded form. Displays, control consoles, and voice communication sets are located in one central office where all system adjustments and decisions will normally originate. A computer in this office will operate all normal functions, initiate certain off-normal functions, perform auxiliary data and event recording, and run simulations as required. Requirements for security, reliability, flexibility, and speed are essentially alike for the different functions. This will enable use of a group of communication channels having uniform characteristics and terminations. Thus, functions may be reassigned to any channel without sacrifice of quality or security. Essential performance goals of the digital transmission system channels and terminals are specified. In addition, the specification requires tests of prototype terminals operating through noisy channels. The control computer will be used to monitor security, reliability, and margins of channels and terminal equipment, and to initiate or suggest channel reassignments. Capability of the computer programs to check data transmission effectiveness and to detect or correct errors may be expanded by further programming if experience should indicate a need.