Turning the page

Emergency services are beginning to use both paging and broadband technology to contact staff, albeit with the use of the latter proving problematic. Swissphone has developed a hybrid solution which it believes can bridge the gap using commercial and mission-critical LTE
Turning the page

The number of pagers in use may be far fewer than the 60 million operating in their 1990s heyday, but despite the advent of broadband technologies and personal smartphones, pagers continue to thrive in niche areas.

The reasons for this are not hard to identify. One-way pagers are small, simple to use and have a battery life of up to three months. Pagers use VHF spectrum, so the signal propagates much further and is better at penetrating buildings than mobile phone or Wi-Fi signals.

Pagers operate over independent, self-reliant infrastructure, so they are highly available and highly reliable. Unlike mobile phone or fixed telephony networks, they can still operate in the event of regional or national power outages.

Pagers remain popular in the before the event. Then when they call, they need confirmation that staff are coming, so if they can’t make it, the next person can be called.”

Technologies in tandem

Naturally, this means that retained firefighters have to carry a pager. But the ubiquity of mobile phones has led some organisations to switch to using mobile apps as an alerting mechanism, which does have the obvious benefit of enabling the firefighter to respond to the alert via the same device. However, the advantage of investing in a regional or nationwide pager network is that it is fully independent and self-reliant.

Zimmermann points out that during the 2016 terrorist bombings in Brussels, both the emergency services’ TETRA network and mobile networks were down, whereas the pager network still worked. healthcare sector, particularly in the UK, and are still widely used by emergency services, especially those organisations that rely on volunteer or retained staff.

These personnel are not equipped with specialist radios at home, and getting hold of them quickly via mobile or home phones is highly impracticable. This makes personnel hard to find. But a fire chief, for example, needs to have a highly reliable and efficient way of alerting retained firefighters.

Speaking of this, Philipp Zimmermann, head of marketing at alerting solutions provider Swissphone, says: “You cannot allow yourself to call double the amount of firefighters. You need just to be sure you have enough.

“So, there is a need to call only the people you really need with the right specialist skills, when you need them. For that kind of targeted alerting, the fire chief needs to know who is available. More recently, mobile networks were out during the storm Arwen in December 2021.

“If you have a mobile app and there is a crisis where the mobile networks do not work, then you cannot call your first-responders,” says Zimmermann. The trade-off here is that the high reliability of pagers is sacrificed for the convenience of mobile phones. Emergency service organisations are therefore having to think about how they can reliably alert people, while giving them the convenience of a mobile phone app.

“If you have a mobile app and there is a crisis where the mobile networks do not work, then you cannot call your first-responders”

Pagers generally provide one-way messaging alerts based on the POCSAG protocol. Of course, one-way pagers have their limitations, but two-way pagers also exist and have done since the mid-1990s, based on the FLEX protocol.

Swissphone introduced POCSAG two-way pagers 10 years ago by integrating relevant mobile standards from GSM over 3G and LTE-M, nowadays.

“This allows the first-responder to reply and say, ‘Yes, I am available’,” says Zimmermann. Two-way paging saves time as it enables more targeted alerting. Rather than having to wait vital tens of minutes for first-responders to turn up at the station, dispatchers using two-way paging systems will be updated much more quickly as to who is available. They can then send out rapid second and third dispatch messages if not enough first-responders say they are on their way after the first message has gone out.

Two-way paging also saves money, as retained firefighters have to be paid if they turn up, even if they are then not required. Two-way paging ensures this does not happen. Discussing this, Zimmermann says: “You save money as you only call as many first-responders as you need, rather than having to call more than you require to provide a safety margin in case not enough people show up.”

The drawback of two-way pagers, however, is that battery consumption increases considerably with the mobile connectivity. A POCSAG one-way pager battery charge can last for up to three months, but a two-way pager is out of charge in two or three days.

According to Zimmermann, Swissphone has overcome this issue by introducing what it calls its s.QUAD pager, which works in conjunction with a mobile phone, integrated with Swissphone’s own s.ONE mobile app. The s.QUAD becomes a two-way pager via the mobile app with the two devices connected by Bluetooth Low Energy (BLE). The pager is thus able to retain its long battery charge, as the mobile handles the energy-consuming radio transmission side. A number of configurations can then be deployed, making the best use of both POCSAG and the smartphone’s connectivity.

“You can configure the app so that it only works fully if it is connected to the pager. But you can also configure it so that it works fully independently on the smartphone too. At the same time, the app can be integrated with the organisation’s message encryption without having to import the keys in first-responders’ private smartphones. This is quite a unique concept from Swissphone,” Zimmermann points out.

Towards mission-critical broadband

According to Zimmermann, Swissphone has been refining these concepts over the past five years. However, it now believes there is an opportunity to adapt its solutions to meet the alerting needs of first-responders planning to migrate to the UK’s Emergency Service Network (ESN) and France’s Réseau Radio du Futur (RRF) nationwide public safety LTE networks.

Conversations with stakeholders of the UK Home Office and France’s Ministry of the Interior reveal that fire brigades in particular are concerned that there is a gap between their legacy alerting systems and what ESN and RRF will deliver, and when it will be delivered.

Graeme Hull, head of international sales and managing director, Swissphone North America, says: “We have this idea of a hybrid network to fill that gap and maybe show them a sensible migration route to whatever ESN develops into.”

Taking the UK as an example, Hull explains that there are 14-15,000 retained firefighters in England and Wales. Currently, the station alerting systems are local and independent of each other. There is no synchronised region-wide or countrywide alerting system. Swissphone specialises in paging networks that cover wide areas where the base stations send out alerts in a synchronised way.

“This is important,” explains Zimmermann, “because if you do not synchronise the transmissions in separate locations, they can erase each other.”

The company has proposed an evolution of fire station alerting in conjunction with ESN to ensure retained firefighters can be alerted simultaneously across multiple brigades in the event of a major incident. As a precursor to this, the company has developed a public emergency alert button in response to a number of power outages that hit mobile and fixed telephony networks in Switzerland two years ago, leaving the public unable to call the emergency services. In those cases, Swissphone deployed buttons on the outside of fire stations in Switzerland for public use.

“If nothing else works, you can go to the fire station and push this button and alert the fire services. The fire brigades have TETRA or Tetrapol radios, so they can call the ambulance service or police. They act like a triage service,” says Zimmermann. “Our networks have the ability to communicate over the air,” he continues.

“At one base station anywhere in the network you can send a message that will hop over the air to the control room. So, all our customers with our region-wide networks can add buttons at the base station and it will link back to the control room even if everything else is out.”

Swissphone customers with existing networks already have the core regional, fully synchronised and self-reliant infrastructure in place. The button is designed to be a simple addition, providing the public with an emergency calling fallback solution in the event of a power blackout.

True hybrid network

Swissphone’s proposals to ESN and RRF involved putting these two concepts together so that POCSAG paging is added as a complement to the mission-critical LTE network. This provides fire chiefs with a highly reliable way to alert volunteer and retained firefighters who do not have an ESN device at home. And they can also integrate the concept of the emergency call button for the general population as well. This arrangement would retain a similar architecture to that which is currently in use with the vast majority of UK fire brigades.

“The key points here are: the input from the control room from the dispatch centre; a transport layer; the station alerting layer; and then another transport layer out to the devices,” says Hull. “It is a true hybrid network. The main differences here being that we are proposing using the ESN network as the transport layer. But there are a whole range of ways you can get the message from the control room to the individual station. In most instances, we’d use the ESN network as a back-up to the fire brigade’s own IP network,” he observes.

Standard one-way POCSAG pagers could also be used, so volunteers would just receive a message and go into the station. Or POCSAG base stations can be combined with the s.ONE server, which would be used in conjunction with a standard POCSAG pager and the s.ONE app on a mobile phone to provide the feedback channel.

“The other hybrid option is to bring in our new mioty low-power wide-area network (LPWAN) IoT technology,” says Hull. “It is a different type of hybrid whereby we are effectively using an IoT technology to give them the option for feedback. That could even be presented as an emergency button that the public could access in the event the complete network was down.”

Swissphone tested a number of LPWAN IoT technologies including LoRa, but decided mioty was the best for a number of reasons. For a start, it is an ETSI standard, unlike the proprietary LoRa approach. A key reservation with most LPWAN protocols is that data is transmitted in one go, so if there is any interference, the data can be lost. Mioty, on the other hand, splits the information into several packages.

“You can lose up to 50 per cent of the packages and still reassemble the information afterwards. That is the reason why mioty is extremely robust,” says Zimmermann. “The power and range of mioty is comparable to LoRa due to regulations within the 868MHz band, but scalability and robustness is special, as you can connect a lot of sensors to one base station with a lot of messages sent per day and it will all come through. The quality of service is excellent. LoRa is not always as reliable.”

Zimmermann says another advantage of mioty in mobile use-cases is that it will successfully transmit to vehicles speeding at 120km/h and even above, while LoRa with high spreading factors shows increased losses, starting at 40km/h.

Hull adds: “We are really trying to present fire brigades with a number of options that are robust but still costeffective. We are dealing with public money here and the budget issue is a real one. By using technologies which are typically cheaper to deploy, like mioty and POCSAG, and blending that with the public layer, like the ESN network, there is a lot of inbuilt resilience and robustness. It also provides options in terms of the types of devices that are used to receive, acknowledge and make sure firefighters are fully in the picture as to what is happening.”

According to Swissphone, it is nearing completion on the development of a mioty base station with an LTE option inside. This unit can be slotted on to its existing POCSAG base stations, so they double up as an regional or national IoT network as well. What this also means is that wireless mioty-enabled public emergency buttons can be deployed anywhere, along with other missioncritical IoT applications. They just need to be within range of a combined POCSAG/mioty base station.

It may ultimately prove that mission-critical LTE networks will develop a network-based way to get in touch with the likes of retained firefighters who may not have an ESN or RRF radio device at home. But Swissphone’s proposed concept offers an economic way of getting round the problem, which ensures reliability and additional resilience.

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