Independence blazes trail into 700 MHz band
Independence, Mo., could soon become the first municipality to operate a 700 MHz mobile radio system. The city is negotiating with Motorola on a proposal to unite its police, fire, public works, public utilities and other departments on a new digital trunking network in that band.
“We have a good [chance] of being one of the first ones actually up and running in the nation,” said John Main, deputy chief of the field operations bureau at the Independence Police Department.
“We expect to have it operating in early 2006,” said Gordon Abraham, a major with the police department who, with Main, led the team that obtained a $5.5 million Department of Homeland Security grant to help fund the system. The total price tag for the system is $7.3 million.
Many communities are developing plans to build 700 MHz networks, using spectrum that Congress has earmarked for public-safety communications. But most of them must wait until TV stations in their areas vacate that band as they make the mandated transition from analog to digital broadcasts.
Independence doesn’t need to wait. The only TV station currently broadcasting in the band is KSMO-TV, Kansas City, and its operations don’t pose a problem. “We’ve talked to the frequency coordinator for the state of Missouri, and they’ve assured us that we’ll get frequencies that cause no interference,” Main said.
Independence is building the new system to improve radio coverage and provide interoperable communications among different city agencies. Today, those agencies operate on a patchwork of frequencies — the police, for example, on 450 MHz and the fire department on 150 MHz. They can’t talk to one another, nor can Independence police and fire officers talk to their counterparts in nearby jurisdictions such as Kansas City, Mo., where public-safety agencies operate on an 800 MHz system, Main said.
Motorola has proposed a six-site Project 25-compliant system that is expected to cover 94% of the city, compared with 68% coverage on the police department’s existing analog system. All of the tower sites would be new. Each city agency would have its own talk groups, but they also could create talk groups for inter-agency communications, said Peter Albara, Motorola’s state account manager for Missouri.
| Current system | Proposed system | |
|---|---|---|
| Agencies supported | Police department. (Other city departments have separate radio systems) | Police, fire, power and light, water, health, animal control, public works, water pollution control and parks and recreation departments |
| Type of system | 400 MHz analog | 700 MHz trunked digital, P25 compliant |
| Area covered | 78 square miles | 78 square miles |
| Minimum coverage in medium density buildings | 68% | 94% |
| Number of antenna sites | 1 | 6, expandable to 15 |
| Interoperability | none | Dual-mode radios provide communications on 800 MHz NPSPAC mutual aid channels |
If it signs the contract, Independence would purchase between 600 and 700 mobile and portable radios and might increase the number to 1000, Main said. These units can be tuned to frequencies in the 700 MHz and 800 MHz band, allowing personnel in Independence to talk with colleagues in other jurisdictions on the 800 MHz National Public Safety Planning Advisor Committee (NPSPAC) channels earmarked for mutual aid interoperability.
Radio systems operating at 700 MHz and 800 MHz offer similar benefits, Albara said, but the UHF band provides one further advantage: clear spectrum. Because no one will be transmitting on neighboring channels once the TV stations move off, public-safety agencies on 700 MHz won’t have to worry about interference. “And as people come on, [the spectrum] will be controlled by the FCC and APCO and those organizations, so that interference situations are avoided,” he said.
Neighboring public-safety agencies might eventually join the Independence network, “thereby enhancing the interoperability among all of us,” Main said. Some will be able to use the antenna sites Independence is building; others might add their own.
Along with individual cities, Independence is working with the Mid America Regional Council, a consortium of public-safety agencies in the Kansas City area. “Hopefully, we’ll expand this to make it a regional project,” Abraham said. State agencies could eventually come onto the system as well.
Independence also received a proposal from M/A-COM. “We felt both of them had outstanding systems,” but Motorola offered lower costs, Main said.
If Independence is the first pioneer to enter the 700 MHz band, it probably won’t be alone for long. California also is developing a system, and New York is eyeing the spectrum as part of its plan to build a statewide radio system, said Ron Haraseth, director of automated frequency coordination at the Association of Public-Safety Communications Officials.
Before moving onto 700 MHz in droves, public agencies will have to wait until enough equipment for that band becomes available, TV stations clear the spectrum and their regional planning bodies gain approval for their 700 MHz plans from the FCC, Haraseth said.
“Right now, the only region that has completed the planning process is Southern California,” he said. “Missouri is right behind them. And there’s a whole bunch that are ready to start filing for their final approvals.”
