MMP-4800 was a MDTMobile Data Terminal, A mobile data terminal (MDT) is a computerized device used in public transit vehicles, taxicabs, commercial trucking fleets, military logistics, and emergency vehicles, such as police cars, to communicate with a central dispatch office. (Mobile Data Terminal) protocol developed by Canadian company Mobile Data International (MDI) in 1982. Used by public safety and commercial industries. Phased out.
Transmitted at 4800 bpsBits per second (bps), had two-way functionality, and occupied 25 kHzKiloHertz (kHz) 10^3 Hz UHFUltra High Frequency (300-3000 MHz)/VHFVery High Frequency (30-300 MHz) voice channel, or 12.5 kHzKiloHertz (kHz) 10^3 Hz sideband.
Users of this included Swedish Police, Phoenix Fire Dept., and other commercial companies.
When MDI was purchased by Motorola in 1988, Motorola decided to discontinue MDI's MMP-4800 protocol in favor of it's own MDC-4800 protocol.