Today, critical communications between first responders – such as police officers, paramedics and firefighters – is compromised by unreliable, ineffective, non-interoperable radio communications systems. To address this, in March 2017 AT&T was selected to build LTE-based FirstNet (First Responder Network Authority), a public safety network. FirstNet will be America’s first broadband network dedicated to emergency services and rolled out across the entire country; including rural and tribal territories. It is designed to provide first responders with access to an interoperable communications system, offering voice, video and data services. However, according to Kevin Persing, Head of Public Safety, North America, at Cobham Wireless, and a board member of the Safer Buildings Coalition (SBC), there is still significant progress to be made before FirstNet is widely accessible in relation to in-building communications.
Deploying LTE for FirstNet
By delivering a public safety network over LTE for the first time, AT&T will be able to offer first responders the capacity and bandwidth needed to communicate and share information during emergencies. The network will leverage standard features associated with the 3GPP LTE standard, such as air interfaces, systems, tools and policy elements. For the first time it will also be able to offer new mission critical voice and data services when they become available.
Deploying a single core network nationwide which is dedicated to public safety reduces the security risks and operational complexity associated with multi-core architectures. It offers end-to-end encryption to keep all traffic on the network protected, whilst also providing local control to support specific situational responses.
Part of AT&T’s contract with FirstNet requires it to expand coverage on the new network using dedicated LTE spectrum across Band 14, part of the 700 MHz spectrum licensed for the network. However, building a standalone public safety network using Band 14 could take years to complete. This is because AT&T will need to build a new virtual network on top of the network it currently operates, as well as new physical infrastructure, such as broadcast towers. It will also need to ensure that mobile handsets are available that are compatible with the network, a responsibility which will also befall the handset manufacturers.
Until Band 14 is developed, traffic for first response on FirstNet will be carried via AT&T’s current commercial spectrum. This traffic will be prioritised over consumer and business data and voice services. The carrier is allocating specific spectrum bands for FirstNet responders, using the carrier’s existing macro network. Although this means that FirstNet is available immediately, this is not considered to be a long-term solution.
Delivering robust in-building coverage
A further challenge for AT&T and FirstNet is deciding how the carrier will deliver in-building coverage universally across the States.
Currently, many local governments in the U.S. have opted-in for compliance with the National Fire Protection Associate (NFPA) Fire Code, and the International Fire Code (IFC) which are designed to improve safety and minimize risk in the event of a fire or other on-site emergency. It comprises a set of requirements to ensure that Fire, EMS and Law Enforcement first responders can communicate effectively, including the provision of a 12-to-24-hour power back-up, and alarming for the communication system. There are also specific requirements on non-interference from other radio services to ensure communications are reliable. To comply with the Fire Code guidelines, any indoor communication system must be designed and deployed to meet NFPA and International Fire Code compliance by the local Authority Having Jurisdiction (AHJ).
Public safety in-building communications systems may now need to comply with both Fire Code and FirstNet where required. Many will need to be re-designed to deliver LTE connectivity in Band 14, and at a considerable cost. Typically, responsibility to meet the code falls on the building owners, who are unlikely to be happy with having to further invest in new equipment to support FirstNet and Fire Code. It could be that some venues may receive support from AT&T or the government, whilst some may not even need to comply at all.
A clear in-building strategy has yet to be defined, but AT&T, FirstNet and the SBC are currently working to address the regulations and code for coverage, which includes the indoor signal strength and the level of coverage that needs to be provided in each building. Once this has been determined, FirstNet will be able to decide how the Fire Code standards apply to the new network. Importantly, public safety coverage technology vendors must be ready to update their in-building coverage solutions to support FirstNet’s specifications, with solutions potentially needing to be retrofitted to support Band 14.
Currently, the U.S. states have opted in for FirstNet, with a universal recognition of the benefits of a nationwide, interoperable broadband public safety network that can provide mutual aid between agencies. Yet, without a clear in-building strategy FirstNet and AT&T still have some significant work to do until the service can be widely utilized.
