Public Safety DAS Distributed Antenna System is a system that ensures first responders firemen, police and emergency personnel to have access to communicate within the facility or building. Commercial DAS objective is to fulfill users on their mobile devices aiming to allocate coverage as well as the capacity to contain the growing number of mobile users. DAS amplifies cellular coverage within buildings no matter the size. This infrastructure literally distributes cell signal over a system of antennas. Cellular coverage degrades inside buildings due to metal and concrete block signal in large buildings with multiple rooms. Amplifying cellular signal through all nooks and crannies of a property is the only solution to this common problem.
Requirements and design for public safety and commercial DAS also differ greatly. Their are specific frequencies that are used when providing public safety which are different than the ones used in a commercial DAS environment. This impacts the antenna placement with commercial DAS which focuses on capacity , re-sectorization is frequently needed to accommodate traffic growth in particular areas at different times. Whereas a public safety relies on coverage at all times, everywhere through the facility. Although commercial DAS and public safety has varying goals, requirements and design they can be on the same system, fiber, coaxial cabling and antenna infrastructure. Integrating both the public safety and the commercial frequency bands in a single infrastructure is possible will an all-digital DAS.
In the circumstance where security and redundancy are of concern, both the commercial and public safety systems can be installed separately. However, its recommended that both systems should be installed in parallel if feasible. This would be beneficial as laying both cable systems at the same time would reduce ceiling and riser work, providing cost savings.
