L.A. on alert: Preparing for the worst
Vulnerability is the threat that has dogged public safety networks since the Sept. 11 attacks.
Small wonder: The World Trade Center collapse destroyed 98 radio antennas, including some belonging to the Port Authority of New York and New Jersey, the New York State Police and the U.S. federal government. Since then, police, fire and EMS agencies have all been asking themselves the same questions: Could it happen to us? If it did, how bad would it be? How would our networks cope?
Los Angeles has been considering these questions carefully. Fortunately for the 3.7 million residents who live here, the answers are reasonably reassuring. Los Angeles is a city that has constantly been bracing itself for disaster — admittedly of the natural, earthquake-style variety — and so it is also well-positioned to protect itself from terrorist attack.
LAPD’s radio networks
The Los Angeles Police Department has a big turf to cover: 460 square miles over a wide variety of terrain.
To do the job, the LAPD uses “about 10 transmit and 23 receive towers spread throughout the city,” said Sergeant Kurt Miles, the officer-in-charge of the LAPD’s master radio system.
“We have two separate and distinct systems in place. One is a Motorola Astro digital voice UHF service (450MHz-512MHz); the other is a mobile data service at 800MHz,” Miles said. Both interface with Los Angeles’ Emergency Command, Control and Communications Systems and the city’s two 9-1-1 dispatch centers: one now in downtown Los Angeles, and the other yet to be opened in the San Fernando Valley.
Still in the midst of deployment, the Motorola Astro system has been going through teething pains. In fact, complaints about reception problems have surfaced in the Los Angeles media, prompting the LAPD to issue a July 31, 2001, news release that stated, “The department is acutely aware of these concerns, and is working in a concerted, cooperative effort with representatives of Motorola to address these issues.”
This said, when performing optimally, the Astro system provides the LAPD with a 57 UHF simulcast system. Providing service to about 10,000 hand-held radios — which double as in-car mobile radios — the simulcast system was chosen for economic reasons. “Even with the $235 million bond that the public authorized in 1992, a trunked radio system would have been too expensive,” Miles said. “Still, even with simulcast, we effectively have access to some 110 voice channels — quite enough for our needs.”
The LAFD/EMS’ radio networks
In contrast to the LAPD, the Los Angeles Fire Department and EMS operate on an 800MHz Motorola analog radio system.
“We have 18 channels available for exclusive fire and EMS use,” said Battalion Chief Thomas H. Franck, section commander for the LAFD’s radio section. “We have nine primary simulcast transmitter sites throughout the city, plus one alternative backup site.” All 10 sites have battery and generator backup systems.
To date, the LAFD/EMS has about 1,600 hand-held radios in service, plus about 800 mobile units installed in trucks and ambulances. “We’re currently deploying the new Motorola XTS 3000R hand-held, which is also analog,” Franck said. “We’ve been testing it extensively for about 18 months now, and hope to roll it out by year’s end.”
L.A.’s response to risk
Let’s talk security. How vulnerable is Los Angeles’ police, fire and EMS radio networks to a terrorist attack?
Well, thanks to the city’s landscape — a mix of mountains and sea plains — the risk is minimal. To get signals everywhere, the city’s public safety networks have had to build a decentralized transmission system.
This means that no single tower or transmit site is indispensable. In fact, the LAPD and LAFD/EMS networks are designed to survive site losses due to earthquakes.
“We have microwave repeaters that shuttle signals between sites,” Miles said. “If we suddenly lose a tower, then we can bounce the signals onto another location.”
Franck added, “We also have pretty good line-of-sight coverage with our hand-helds. Even if all of our towers went down, we can still manage on a region-by-region basis.”
The LAPD and LAFD/EMS have designed their systems to fragment into small stand-alone networks, should a catastrophic failure occur.
A case in point: In this scenario, each of the city’s 18 police stations would handle radio traffic for their respective LAPD officers. “In this way, our people would be able to talk to each other and coordinate their moves, without being dispatched by 9-1-1,” Miles said.
Meanwhile, the LAFD/EMS would cope in a similar manner, with each firehall taking over responsibility for its region.
“This approach allows us to cope with the complete annihilation of our dispatch centers either by terrorists or earthquakes,” Franck said. “Granted, the system won’t work as fast or smoothly, but it will function nevertheless.”
Not interoperable, but interconnected
As noted earlier, the LAPD and LAFD/EMS aren’t on a common radio system. Hence, in times of crisis, they could have trouble talking to each other.
To minimize this problem, the LAFD/EMS has bought enough Astro radios to put one into each and every LAFD/EMS vehicle. “This works pretty well in keeping us interconnected,” Franck said.
As well, the fact that LAPD and LAFD/EMS dispatch centers are side-by-side keeps the two in close contact. Meanwhile, their physical location 60 feet below City Hall offers some degree of protection from attack.
This said, the LAFD/EMS has wisely chosen to take part in the National Institute of Justice’s Office of State and Local Disaster Preparedness Services radio interoperability project. Thanks to funds from the Department of Justice’s AGILE program (Advanced Generation of Interoperability for Law Enforcement), the LAFD/EMS has purchased four TRP-1000 transportable interconnect systems from JPS Communications, Raleigh, NC.
The TRP-1000 operates as a kind of “telephone switch” for mobile radio networks. You plug in as many as 10 kinds of radios, and the TRP-1000’s software switches calls back and forth between them.
“It was the Oklahoma City bombing that motivated the DOJ to fund the TRP-1000s,” Franck said. “During that tragedy, the various public safety agencies had a hard time communicating with each other — all while coping with rumors of a secondary device waiting to explode at the scene.”
Sept. 11 leads to some change
Taken as a whole, Los Angeles’ networks are pretty well-placed to cope with terrorist attacks.
The Sept. 11 attacks still came as a wake-up call to the city. “It introduced a new paradigm for looking at catastrophic failures,” Franck said. “For instance, how would we recall people to duty if our centrally located phone system was destroyed?”
The answer? The LAFD/EMS has duplicated all of its essential records and distributed them among various stations. In this way, even if the dispatch and back dispatch centers are lost, fire and EMS crews can keep doing their jobs.
In the wake of the Sept. 11 attacks, it would be wrong to say that any one agency is prepared for whatever happens.
However, with their distributed resources, backup plans and ability to function with the complete loss of command and control, Los Angeles’ police, fire and EMS crews seem better able to cope than most. Living in the shadow of impending natural disaster, it’s not such a stretch preparing for manmade holocausts as well.
Careless is a freelance telecommunications writer based in Ottawa, ON, Canada. His email address is firstname.lastname@example.org.