BART Advanced Automated Train Control (AATC)

Description

• Planned to replace long-troubled BART (Bay Area Rapid Transit, San Francisco) track circuit based designs in a “standalone” manner. Several “kludges” for train separation would be replaced.
• Derived from military vehicle location and comms system by Hughes Aircraft later acquired by Raytheon.
• RFRadio Frequency comms provided location by triangulation plus high speed data comms with trains.
• Turned over to Harmon when Raytheon realized they couldn’t commercialize.
• Many technical issues with translating from surface to subway application.
• Development halted by GE after takeover of Harmon and subsequent customer issues.

• SYSTEM: Advanced Automatic Train Control (BART)
• SUPPLIER(s): Raytheon then Harmon then GE
• STRUCTURE: ISO 7 layer
• MESSAGING STD: Military EPLRS
• MAX BIT RATE: Very high - 128 KBPS
• FREQ BAND: UHFUltra High Frequency (300-3000 MHz) – military 420 MHzMegaHertz (MHz) 10^6 Hz proposed
• RADIO MFGR: Raytheon (for demonstrations)
• COMMS RANGE: Short range multiple TXTransmit/RXReceive for location and data transmission
• COMMS BETWEEN: Among multiple waysides and to trains at all times
• STATUS: Contract cancelled / project abandoned by GE after Harmon acquisition.