Quick Guide to Radio & Cellular Building Coverage Systems

Without proper communication, your teams are unable to stay connected with each other and your organization’s productivity and safety suffers. Even more alarming is the safety of staff or visitors in areas with weak signal coverage. This creates a lack of situational awareness for those who need it most: first responders.

Legal statutes may require stringent two-way radio coverage for public safety communications in the Mid-Atlantic states, which means that you’ll need powerful signal boosters installed throughout your building. Let Wireless Inc. help by describing what such an install might look like so you have all the information needed before making any decisions. 

What are Bi-Directional Amplifiers (BDA) and Distributed Antenna Systems (DAS)?

When struggling with poor two-way radio or cell phone reception, organizations look for cost effective and technically sound solutions. In-building signal boosters can be the answer to this problem by using three critical elements:     

  • Distributed Antenna Systems (DASs) throughout buildings which improves coverage in difficult areas like stairwells or underground hallways, by using a combination of antennas and leaky coaxial cable.
  • Bi-directional Amplifiers (BDAs) are used when two way radio communication is necessary but not always feasible due to challenging building zones such as parking garages or tunnels.
  • System Design & Installation – Working with an experienced wireless technology system integrator is key to a successful project. Your partner will take into account radio frequencies, coverage and capacity requirements, and professional installation and maintenance.   

What commercial & government organizations use BDA and DAS solutions?

Bi-Directional Amplifiers are found in many buildings, including hospitals and large office structures. They are also popular at schools, sports arenas, casinos, and more places where communication is important for facilities staff members who use two-way radio systems. Bi-directional amplifier systems improve team communication by eliminating dead zones while strengthening signals inside the building.

These devices also help meet Public Safety Radio coverage requirements, essential when operating on 700 MHz frequency ranges. Public Safety radios are a critical component of emergency response. They allow first responders to stay in contact with each other and provide vital information about the event; they help keep everyone safer, but also make it easier for emergency responders to serve building occupants better during emergencies.

Cell phone signal booster systems improve coverage inside buildings. We recommended to install both types of systems: one system for cellular devices (Cellular signal BDA) and another system specifically designed for public safety radio communications.  

Implementation Process For DAS & BDA Systems

When installing a BDA/DAS system, there are many things to consider. That’s why most facilities and construction contractors turn to an experienced wireless provider for assistance. To determine the best system design and installation, your provider may ask for floor plans or wiring schematics as well do some site walks in order to measure radio signal strength and plan out the system correctly before installation begins.

To guarantee maximum signal input, the receiving antenna should be line-of-sight to the transmitting base station, while the distribution antenna(s) should be as close to the service sections as possible. Where they are needed, BDAs should be placed as close to the receiving antenna as possible and point away from the transmitting site so they can deliver a strong signal throughout the building. 

Compliance Requirements

Public safety is one of the most important things to keep in mind when designing a network. The signal strength for first responders needs to be exceptional during an emergency, so many cities and states have building codes that specify BDA and DAS installation requirements.

The two most commonly used statutes for wireless signal coverage are the International Fire Code (IFC) and the National Fire Protection Association (NFPA). These codes regulate how strong each facility needs its public safety two-way radio communications signals need to be so that first responders have instant communications in an emergency.  

  • NFPA 72 Chapter 24 code states that 90% of in-building coverage is mandatory. However, the requirement jumps to 99% for critical areas such as elevator lobbies, exit stairs and passageways, and fire pump rooms.   

Furthermore, public safety BDAs need to work under high heat and high humidity, while being able to function on a backup battery for 12 to 24 hours (depending on code requirements).   

  • IFC-510 code requires 95% in-building wireless signal coverage with a minimum signal strength of -95 dB. 

Selecting a Wireless System Contractor for your project

One of the key steps in a successful system implementation is selecting your Wireless technology partner. Your technology system integrator will be responsible for:  

  • Engineering & Design – Working with a partner for your system design and engineering will help get your project started in the right direction. Your contractor will assist in coverage maps, site walk throughs, building plan reviews, and selecting the best places for installation of the system.  
  • Equipment Selection – Your partner will provide you with a couple of options for BDA and DAS equipment for your project. Depending on your budget your partner will be able to recommend a system to achieve your building coverage goals and make you compliant with local building requirements.
  • Installation & Maintenance – Proper installation of your system is critical for long term project success. Making sure the contractor has maximized coverage by optimizing placement of wireless components is key. Additionally after the system is installed working on a defined ongoing maintenance schedule is important. Your contractor will be able to tune your system so that maximum radio waves are transmitting in your building. Also your contractor will be able to certify your system to be compliant with local building codes.


With a powerful BDA & DAS system at your disposal & experience wireless technology partner like Wireless Inc., you can rest assured that public safety agencies in Maryland, Washington DC, Pennsylvania, Virginia, and New Jersey will have all the information they need to keep everyone safe.

Our team of experts are ready and waiting for any questions or concerns about designing these systems so contact us today! 

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