Bandwidth reduction worries emergency dispatchers

Kitsap County’s emergency crews have started bracing an FCC-mandated switch to narrowbanding, a communications system that’s less clear but demands less of the radio spectrum than what’s currently used.

Kitsap County’s emergency crews have started bracing an FCC-mandated switch to narrowbanding, a communications system that’s less clear but demands less of the radio spectrum than what’s currently used.

The FCC pushed for the switch to free up radio space, a resource with increasingly limited supply and high demand.

“The use of radio spectrum … has skyrocketed in recent years,” noted Richard Kirton, the director of CenCom, which oversees communications for local emergency workers, during a presentation to South Kitsap Fire and Rescue.

A lot of newer communication technology, like cell phones, use it.

“Since you can’t create more spectrum, the FCC decided to make the portions allocated to each licensee smaller,” and “reduced the maximum allowable power settings on transmission equipment,” Kirton said.

Right now, one radio channel uses 25 kHz of bandwidth, and after the switch, each station will use 12.5 Hz of bandwidth. Another reduction has been slated to cut CenCom’s use of the bandwidth nearly in half again, to 6.5 Hz.

Technology has advanced to the point that it’s not an impossible switch. But many of the stations that have already started narrowbanding tell “horror stories” about it, Kirton said.

Poor communication equipment can have a serious negative impact on first responders, Lieutenant John Sprague, with the patrol division at the sheriff’s office, said.

It nearly cost several deputies their lives, in the spring of 2006, for example.

A property-owner at Menzies Rd SE had requested that deputies investigate an unwanted trailer.

When the deputies arrived at the scene, a man came out of the trailer and shot at them.

The deputies dropped to the ground for cover, and tried to radio for backup. But it wasn’t clear what they were saying, or where they were located.

“That was a dead-spot in the county,” Sprague said. “We couldn’t understand a whole lot of what the deputies were saying, and we couldn’t coordinate a safe way to get in and get them out.”

That’s the sort of thing that could happen, if the new communications system doesn’t work well, Sprague said.

“Say you were sent to a building, looking for a suspect or burglar in the middle of the night,” he said. “A deputy goes in and is trying to communicate to somebody outside that the suspect is going to the north door.

It could be a significant situation, if you can’t understand the words.”

In preliminary local field tests, that Sprague helped conduct, the narrowbanding system hasn’t worked as badly as predicted.

“Outdoors, it was fine,” he said. “When the signal was strong, it sounded better than what we use today, maybe a little, but when we used it indoors, the signal got weak.

It was usable either way,” he said.

If CenCom had more money, Kirton said, it could provide better equipment.

It could, for example, switch to a digital system in 1 to 2 years for $4 to $6 million, or it could build new towers in 1 to 5 years, for $1 million for a full tower to $150,000 for a small pole.

Small tweaks to the narrowbanding system to the tune of $100,000 seems like a more reasonable approach, Kirton said.

“I think that CenCom’s technical staff and engineers are taking all the reasonable steps they can to give us what they can within budgetary constraints,” said Sprague.

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