Hybrid DAS Solution
We have all seen fire department water standpipes outside buildings and probably not paid too much attention to them. When a fire pumper arrives, they supply their water into the standpipe which distributes water into pre-installed pipes in the interior of the building, providing much needed fire protection.
Just like water, providing fireground radio communications inside a building is critical to firefighter safety. There are several ways to address in-building coverage for firefighters, and a number of fire departments have taken a unique approach to solving in-building coverage by using what is known as the “hybrid DAS ” or the “RF Standpipe” method.
A hybrid DAS is made up of two coverage solutions offered from Motorola Solutions, each with a slight variation. The first solution is a distributed antenna system (DAS) consisting of coaxial cable antennas which are strategically placed throughout the building. The Bi-Directional Amplifier (BDA) which would normally amplify the signal is replaced with a Motorola Solutions suitcase vehicle repeater that the fire department brings with them on the call.
When the fire department arrives at the building, they unload their suitcase vehicle repeater and connect it to a main RF connection which might be located on the outside of the building or in a fire pump room. The vehicle repeater feeds radio signals into the pre-installed DAS, which allows RF signals to travel throughout the building, just like a standpipe delivers water throughout the building. When the incident is over, the firefighters simply disconnect the suitcase vehicle repeater and leave.
Fire departments have used the “hybrid DAS solution” in a number of unique applications to address radio coverage challenges.
- One fire department had coverage issues on a subway platform: they wanted a solution that allowed for quick deployment and was economical at the same time. They pre-installed coaxial cable down a riser which led to the platform. The cable was terminated with a low-profile antenna on the subway platform ceiling. When responding to a call, the suitcase vehicle repeater is brought to the outside of the station and connected to the coaxial cable, providing much needed radio coverage.
- A fire department at a U.S. Navy yard installed a Hybrid DAS using a pre-installed “leaky feeder”/radiating cable which was installed through the center of a ship. A suitcase vehicle repeater was then connected to the radiating cable and to a P25 antenna topside. The suitcase vehicle repeater repeated locally (extending coverage between users in the ship) and also relayed the communications back to the P25 radio system. The ship’s onboard maintenance team was impressed by this solution and took it upon themselves to procure a suitcase vehicle repeater of their own and to use when work was needed to be done on the vessel.
- A recently built building had a DAS system installed, and the planned BDA was going to arrive a few days late. In order to provide much needed radio communications into the building, the fire department put into use their spare suitcase vehicle repeater until the BDA arrived.
Bring Your Own Repeater (B.Y.O.R.) provides instant radio communications and can be used in a variety of applications. Firefighters trust their own equipment; that’s why you’ll see them bring their own fire hoses to a scene. Communications is equally critical, so why not bring their own suitcase vehicle repeater?
