System moves communications from desktop to dashboard
- By Jason Miller
- Nov 07, 2001
The Sheriff's Office in Pinellas County, Fla., uses an 11-year-old VHF dumb terminal mobile communications system that badly needs an upgrade. So when Motorola Inc. asked the office to test an experimental 700-MHz voice, video and data communications system, officials signed up quickly.
Motorola equipped three squad cars, a surveillance van, an indoor mobile unit, and fire and emergency management service vehicles with the system'called the Greenhouse Project'to operate in a six-mile radius around Sheriff's Office headquarters.
Even though the agency uses the system on a limited basis, officials said the experience is helping them decide what to buy next.
'They are providing us the hardware, and we are providing them our expertise and real-life experiences,' said Dave Byrum, communications engineer. 'We need to replace about 550 units, which will be quite an undertaking. By taking part in the Greenhouse Project, we are seeing a glimpse of the future and what our next system might include.'
The Greenhouse Project is a major improvement over Pinellas County's existing communications gear. With the old equipment, officers can execute only basic functions from their cars such as sending text messages, searching the motor vehicle database and receiving dispatches.
The Greenhouse Project, which costs the county nothing, gives officers all the functions of their desktop PCs in their cars. Users can access the Internet, the office's intranet, the FBI's National Crime Information Center as well as other state and local databases in seconds. The system allows officers to complete paperwork in the car and take part in full-duplex videoconferencing.
The system includes a camera mounted on the windshield, a flat-panel touch-screen color monitor and a hand microphone on the dashboard. The keyboard sits between the two front seats, and a 333-MHz Pentium III with 128M of RAM and a 6G hard drive is connected to the back of the driver's seat.
Motorola developed the scalable adaptive modulation protocol that transmits information at 460 kilobytes per second using car-mounted antennas and a communications tower.
The tower relays the signal to the base station by fiber-optic cable to give officers Internet and intranet access. Motorola submitted the protocol to the Telecommunications Industry Association to become the standard for 700-MHz systems.
'The speed of the system is comparable to that of a LAN,' Byrum said. 'That is what makes it a practical system because large files move quickly, and officers can do so much with it.'
The system also equips cars with the Placer 450, a Global Positioning System receiver from Trimble Navigation Limited of Sunnyvale, Calif. GPS allows mobile officers and headquarters dispatchers to see where all vehicles are in real time on a digital map.
The Greenhouse Project will continue indefinitely, Byrum said.
'We would like to see this deployed countywide when the time is right,' he added. 'We feel like we are helping steer the future.'