The Emergency Services Network (ESN) is built to robust mission-critical standards to guarantee high levels of availability and connectivity for the emergency services, but attention also needs to be given to indoor coverage.
The UK was the first country to pioneer the transition of its nationwide emergency services communications system from a traditional narrowband two-way radio network to a 3GPP industry standards-based 4G LTE broadband solution. This was a bold move at the time, but it is now widely agreed to be the way forward for mission-critical public-safety communications networks. Other countries have since followed our lead, which demonstrates that the UK Home Office’s decision was a sound strategy.
The emergency services play a vital role in responding to critical incidents and keeping us safe. But to operate effectively they need ultra-reliable mission-critical communications. To meet that need, Great Britain’s Emergency Services Network (ESN) is being built to 3GPP-compliant mission-critical 4G specifications.
The most immediate benefit for the emergency services is a huge uplift in data capabilities, including real-time video. They also gain enhanced digital voice quality and increased natural resilience through extensive overlapping 4G base station coverage.
The switch from narrowband to broadband allows emergency services personnel to take advantage of the far larger global broadband ecosystem with all the considerable benefits that economies of scale bring. ESN devices also provide an easy transition, as operating systems and smartphone form factors are familiar to users.
ESN can significantly enhance everyday operations by delivering job information, incident messaging, in-vehicle mobile data terminals and on-the-move access to databases and applications. Emergency services personnel will be able to utilise a wide range of applications in the field without having to go through control rooms or return to base. This could considerably enhance the speed and effectiveness of their response to tasks and incidents.
4G broadband networks offer increased capacity and faster data transfer speeds compared with narrowband networks. However, even standard commercial 4G network customers can experience variable performance depending on user numbers and location. But ESN users benefit from guaranteed bandwidth and access, which provides a consistent broadband experience.
Data transfer speeds can be up to hundreds of times faster than the current mission-critical narrowband data solution provided by TETRA technology. For example, the speed of transferring a 10MB file reduces from around 12 minutes on TETRA to just a few seconds on 4G.
ESN users, who will eventually number in the hundreds of thousands, will be sharing a commercial network with EE’s commercial customers, which means they benefit from our continued investment in our 4G network. However, there is no need for concern over their ability to access the network in daily operation, and particularly in emergency situations. This is because ESN users can be granted the highest priority across the entire commercial network. The emergency services will always get the connections they need for those critical moments even at crowded locations such as large sporting and social events or during major public incidents.
A mission critical emergency services communications network must meet far more stringent criteria than a consumer network when it comes to reliability, availability, robustness, security and service levels. ESN meets these requirements in a number of ways.
The network must be available wherever the emergency services need to operate. EE has upgraded over 19,500 existing masts to be ESN-capable across its commercial mobile network. Coverage has been augmented by the addition of more than 650 new 4G sites, an additional 292 Extended Area Service (EAS) sites built by the Home Office in some of the most rural and remote parts of Britain, and in 71 special locations like road and rail tunnels. ESN coverage is also being implemented in high-speed vehicles and to support airborne and coastal operations.

To guarantee high levels of availability the network needs to be resilient enough to cope with extreme weather conditions and power outages. 4G network design means that ESN benefits from overlapping base station coverage in many areas, so if a base station goes off the air, transmissions will automatically switch to another nearby site.
More isolated rural sites have enhanced power back-up to maintain coverage. Others may have dual backhaul solutions for added resilience. A range of temporary mobile coverage and satellite solutions are also available for emergency situations or to provide additional capacity at major events.
Enhanced security is another key requirement and while ESN shares the same radio access network (RAN) with consumers, it has its own dedicated, secure core network. This provides secure integration with the IT systems and control rooms of user organisations. Only ESN-approved users operating via ESN-approved equipment with an ESN-SIM can access the network.
ESN users receive a premium service. Wherever and whenever required, they have priority access over all other network traffic to ensure their critical voice and data communications get through. They also benefit from enhanced service level agreements (SLAs) for service availability on the ESN network. This includes services delivered via additional ESN coverage extension solutions provided via EE as the authorised coverage services supplier.
When the ESN programme began, the Home Office and the three emergency services identified their critical operating locations where the mission-critical communications they rely on are deemed essential. New network deployments prioritised those locations including, along road and rail tunnels, headquarters buildings and main service locations.
Particular attention now needs to be given to indoor location coverage. The emergency services are currently checking ESN coverage provision in their own buildings and other common working locations by using ESN Assure devices to confirm whether adequate signal coverage is available or not. However, Fire & Rescue Services also need to consider ESN coverage availability within other critical operating locations. This includes high-risk multiple-occupancy buildings or venues that attract large numbers of the public such as stadiums, shopping centres and stations.
It is vitally important that premises owners and managers start thinking about how ESN coverage is provided across their estates if the emergency services are required to operate regularly within them. A full suite of ESN-certified Coverage-as-a-Service solutions are now available to expand and enhance coverage in any type or size of location. So, if ESN network service is required for mission-critical public-safety communications in these kinds of locations, they should review their ESN coverage with ESN Programme representatives for further guidance.
For more information, go to www.gov.uk/government/publications/the-emergency-services-mobile-communications-programme/emergency-services-network