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The Bi-Directional Amplifier (BDA) is the newest edition to Life Safety in the state of Florida. The Florida Fire Prevention Code (NFPA 1) section 11.10.1 states that “In all new and existing buildings, minimum radio signal strength for fire department communications shall be maintained at a level determined by the authority having jurisdiction (Committee NFPA 1: Fire Code 2018). That authority having jurisdiction for our local Tampa Bay area is the Hillsborough County Fire Rescue department and they have posted their own requirements along with the Florida Senate for emergency communication standards. All existing “Hi-rise” buildings, 75 feet tall or more, must comply by Jan. 1st 2022, all existing apartment complexes must comply by 2025, and all existing buildings that do not comply with the Hillsborough County Fire Rescue department standards were supposed to have applied for permit by December of 2019 (Senate Florida Legislature) . Several building owners are unaware of the aforementioned changes and it is extremely important to efficiently identify the buildings that do not comply with the latest regulations.

To begin determining the best fix for soft spots in public safety radio transmissions I considered three separate FCC callsigns that cover the emergency radio channels around Hillsborough County. Next, I recorded the amount of Watts each tower is using to then convert to decibel gain (dB) that each tower produces. I determined that greater the power (Watts) that you push through a tower has a decreasing rate of decibels produced per watt and therefore not an option to solve the problem at hand. Then I derived an expression for “Free Space Path Loss (FSPL) in dB” that shows the dissipation of radio signal over a given distance. Using this formula, I realized I may not be able to provide an overall solution for the lack of radio signal, but I would be able to locate areas that will require the installation of a radio amplification system. Therefore, using derivative and integration techniques, I have designed a precise method for mapping areas of radio propagation around Hillsborough County, which in turn, show areas that do not receive the minimal -95dB radio strength and must have a BDA installed.

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License.




Arcadii Grinshpan, Mathematics and Statistics

Arsalan Akram Malik, Mathematics and Statistics

Sean Collins, Fort Knox Fire and Communications

Problem Suggested By:

Austin Collins