Wireless system passes the tornado test
Wireless system passes the tornado test
Texas sheriff's department remains online during unexpected disaster
By Eric Hartley
Special to GCN
If the tornadoes that struck Tarrant County, Texas, in March had come a year earlier, the results might have been strikingly different. But thanks to a digital wireless communications system installed late last year, the county's Sheriff's Department was able to help its 1.3 million residents weather the storm.
The Tarrant County, Texas, Sheriff's Department relies on ruggedized notebooks running Packet Cluster Patrol to communicate with officers in the field.
The county, which is west of Dallas in northeastern Texas, includes Arlington and Fort Worth, and is the fourth-most populous county in the state. The Sheriff's Department has 1,350 officers, about 500 of whom are sworn, said Lt. Robert Durko of the department's Communications Division.
The department began planning to replace its communications system early in 1999, partly as preparation for possible year 2000 date rollover problems, Durko said. The previous system had several shortcomings, the main one being that the terminals were hard-mounted in patrol cars and weren't portable.
Officials in the department heard about the PacketCluster Patrol system from other departments in the area that were using the system, Durko said. The department purchased 10 fixed units as well as 45 remote units for officers on beats such as criminal investigations, warrants and patrol. The complete system, from Cerulean Technology Inc. of Marlborough, Mass., cost about $385,000.Communications went dead
Durko said all Sheriff's Department personnel completed PacketCluster software training in about a week.
The system uses specially designed software on ruggedized notebook computers from Itronix Corp. of Spokane, Wash., to relay messages to and from officers in the field. The data is transmitted over an AT&T Corp. Cellular Digital Packet Data network. The department pays about $45 monthly for each unit to use the AT&T network.
Durko said the notebooks in the field use Microsoft Windows NT, while the client machines run Windows 98.
The two tornadoes that struck Tarrant County on March 28 were the first major test of the PacketCluster Patrol system. The damage from the storms was so severe that President Clinton declared the county a federal disaster area. Worse, the storms were completely unexpected.
'They said a tornado could never hit' the area, Durko said. But when the storms did, virtually all communications went dead. The storm cut power lines, and most cellular phones and pagers didn't work. By using the newly-installed Cerulean system, officials at department headquarters were able to keep in touch with officers in the field and respond to emergencies.
'We used it to send people where they needed to be,' Durko said.
If not for the PacketCluster Patrol system, the county's radio network would have been completely overloaded, because most emergency personnel in the county needed to use it at the same time, Durko said.Useful in everyday situations
Beyond its uses in disasters, the system has some everyday advantages over other technologies, Durko said. Officers can be given more complete information when they are sent on a call. Later this year, the department plans to enable officers to file reports from the field using CDPD technology, eliminating the need for a trip to headquarters to submit a report.
David Grip of Cerulean Technology said the PacketCluster technology is more secure than traditional voice systems because data encryption is built into the product.
Only users on a preset list can log on to the system, Grip said. Though it would be difficult to intercept a message due to the system's data compression and its use of a digital network, someone who did manage to intercept a communication would still have to defeat the 158-bit encryption to decode the message.
Currently the system transmits data at 19.2 Kbps, Durko said, but that speed likely will increase. Technology developments could bring transmission speeds up to 384 Kbps, which would enable functions like live video streaming from patrol cars to headquarters.
County officials plan to expand the use of similar technologies to other departments, including constables and fire marshals.