Richard Martin reviews the state of paging in critical communications and compares the different paging and alerting options available to operators and end-users

How many people do you know without a phone? Pretty well anybody working in any sort of profession or a critical job will have one, even if they also have a PMR radio. We use our mobile phone for our social media, personal calls, emails, messages and entertainment; and carry it around at all times. So why would we need a pager?

The traditional paging community includes volunteers or part-time users who need to receive a message wherever they are. Let’s look at some examples. In the UK, there’s the RNLI lifeboat organisation, which is staffed by volunteer crews in coastal communities. Volunteers come from all walks of life; when an emergency happens, their pagers vibrate or ring and they know they have to get to the boat. In Germany the fire service relies on part-time officers. Both types of user share characteristics such as professionalism, training and commitment. They are serious about their role, and that reflects on their willingness to carry a pager and respond when alerted. Other types of volunteer may not wish to carry a pager but would be prepared to have an application on their mobile phone and respond if available. First-aid volunteers, volunteer social workers, and others prepared to offer assistance in their community, could be said to fall into this category. The fact that there are different methods of alerting and multiple technologies is therefore a good thing, and devices and solutions can be matched to the needs of different classes of user and situation.

Digital paging – POCSAG
Digital paging has been the norm in Europe for some time, but analogue paging is still in use in North America. In 1976, work began on developing a new method for wide-area paging, and in 1981 the forerunner of the ITU-R approved the digital standard that became POCSAG. Now widely used in Europe and Australia, it can operate at three speeds: 512bps, 1,200bps or 2,400bps.

Derek Banner of the Critical Messaging Association of Europe (CMA-E) is in a strong position to make the case for using POCSAG in public safety. “Belgium is a good example of how POCSAG is working alongside TETRA in public safety. Astrid has deployed its second generation of paging network with around 200 base stations. Critical users get excellent coverage with their pagers, including in-building and underground areas.”

He adds that many manufacturers offer pagers with an uplink using cellular and that “this enables the controller or dispatcher to allocate resources more effectively to a particular incident”.

Why use a pager if the user has a mobile phone? “Pagers are favoured by the more dedicated volunteer or part-time responder, they are committed to carry the pager and will respond more readily when it alerts. With a phone there are texts and social media alerts coming in constantly and it is easy to ignore these. A pager is different and draws the user’s attention.”

Banner adds that battery life is also a factor. “Pagers will generally last for several working days, while a smartphone needs regular charging. A user can grab their pager and rush out of their home with a high degree of confidence that it will stay working for the whole day.”

He says CMA-E’s view is that those looking to send and receive critical messages “should not be trusting one network alone, whether that network be TETRA, LTE or any other. They should have a back-up or redundant network that is totally isolated from the main carrier. Modern networks are unlikely to totally break down, but they can get congested or hacked, and users are often out of coverage. We advocate the use of radio paging as a back-up; it is simple to operate, and very reliable.”

Angelo Saccoccia, CEO of Swissphone, said: “We expect paging to become even more robust. We expect to see a growth in self-reliant alerting networks with emergency power supplies, multiple redundant components and alternative methods of accessing the system. These self-reliant networks will provide a fallback for TETRA and LTE voice and data networks in case of a blackout or if networks become congested.

“We recognize that volunteer and part-time teams are a scarce resource and there is a need to use their time in the most effective way. Hybrid POCSAG terminals with integrated cellular and GPS modules can help to alert them in a targeted way. By allowing the teams to provide status updates and feedback after an alert, these terminals make the alerting processes more efficient, saving rescue organisations time and money.”

Igor Alexeev of Oelmann Elektronik in Germany, a company that provides paging solutions using several technologies including TETRA, strongly advocates the use of POCSAG even where there is TETRA available. “Getting complete coverage is simpler and less costly with POCSAG, in the Netherlands the geography was particularly favourable and a nationwide network was very cost-effective.”

He notes some additional features on the pagers. “Using Bluetooth, we have added an emergency button for critical users, and we can link to indoor beacons for accurate indoor location. We have seen an increased emphasis on the personal security of users, who need to be monitored if there are dangerous areas where entry needs to be controlled. We have examples of this in the oil industry. Connecting to biosensors or other detectors on the user can enhance user safety; for example, automatic man-down alarms can be sent over cellular networks to the controller. In the future we see the market for POCSAG as a machine-to-machine connection developing further. We are already seeing it being used to connect and activate emergency sirens.”

TETRA pagers
The German BDBOS network is the largest TETRA network in the world and is now widely used by the emergency services, and Motorola Solutions and Airbus are promoting TETRA paging in Germany. As this TETRA network is maturing and stable, they point to the advantages of using it as a two-way secure and resilient solution and the ease of integrating it with TETRA dispatching and control systems.

Götz Kettner is the key account manager for public safety at Airbus in Germany. “The Airbus P8GR programme began with requirements in the German state of Hesse for an alerting device for professional and volunteer firemen. From the start of the project in 2013, Airbus has now rolled out 40,000 units into the field. Most users are fire personnel, but some other rescue and medical teams are using it as well,” he says.

Raul Carpio from Motorola Solutions tells a similar story regarding its PG2200 two-way TETRA pager. “The fire services in Germany operate with many volunteer firefighters, so they need a fast and reliable method of alerting their teams, and TETRA fits because of its coverage and security,” he says.

Kettner adds: “The pager has to be small and rugged. The alerting tone and vibration must be loud and easy to hear or feel. Our team worked to ensure good sensitivity so that alerts will be received wherever the person is located, including indoors. We have ensured good battery life of up to 48 hours on standby. As well as Hesse, we are expecting demands for the unit in other German states. Standard TETRA features such as security and disable are supported.”

Carpio says: “Key among their requirements was for the unit to be small and easy to use with one hand, but pack a punch in terms of the sensitivity and coverage. The vibration mode is powerful enough to be felt at any time even when running or exercising. The main design challenges were to get the most out of the internal antenna, and give extended battery life up to 48 hours.”

The pager is also fitted with a man-down sensor to alert the controller in the event of user inactivity.

Carpio adds that in Germany, “TETRA makes sense where it is widely available and under the control of the same authority as the rest of the critical communications network. The network is in no danger of being swamped by calls from the public and is resilient and secure.”

Both manufacturers offer a home unit, Kettner says. “This is more than a charger and can be connected to an external antenna for improved reception. It has a USB connector and can also be linked to speakers for louder alerts or to an LED lamp for alert indication.”

Carpio adds: “The Motorola Solutions home base station/intelligent charger has an SMA [SubMiniature version A] swivel antenna to ensure good indoor coverage. There is also an integrated LED warning light and a relay connector for additional alerting devices. The pager can receive updates such as new groups over the air; software updates can be made when the unit is attached to a PC at home or in the office.”

Kettner describes how the Airbus unit is used. “As this is a two-way system, the dispatcher can send a request and then get responses from individual users to know who is available to attend the incident. The controller can then task those available and stand the others down.” Airbus provides the protocol for this to the command and control system supplier, which then integrates it into their overall solution. The user selects one of a predetermined list of status messages. Kettner adds that “in the future we are looking at providing the capability to expand the user status information to local fire stations or even mobile controllers, as well as in the Command Centre”.

Carpio talks us through the Motorola Solutions back-office solution. “We have used our existing Call Out solution with the pager, this is something we have offered on our TETRA radios and it was a natural progression to offer it with the pager. Users show up on the dispatcher’s screens as the pagers are fitted with GPS satellite navigation location services. When the dispatcher is alerted to an incident they can see who is nearest either to the event or their home fire station; these people can then be sent the alert. When the user gets this, they have to respond.” Resource management is improved, and once a team is assigned, other officers are then available for another call. The back-office application also includes the ability to audit an incident after the event.

There are clear similarities between the Motorola Solutions and Airbus solutions, which is no surprise as they are addressing the same market and user profile.

Paging over cellular
There are many ways mobile phones can be used for alerting, and one example comes from Ciaran Mulloy of Druid Software, based in Ireland.

Mulloy says: “Our application is called Raemis, which stands for RA(dio) EMIS(sary) and provides the full functionality of a 2G, 3G or 4G private mobile network. It is typically configured as a mission-critical dedicated mobile network for a large hospital. This is important as the hospital is not reliant on a public mobile operator to deliver its communications infrastructure. We now have access to 2G and 4G private radio spectrum through the UK.”

He adds: “If voice and paging is required then a 2G system is adequate, or a 4G system to include data coverage. Paging on mobile handsets is directly replicated using Flash Messages where the handset beeps and displays a message on the screen until saved or deleted. Paging/SMS messaging is more reliable than dedicated over-the-top apps, as these can sometimes be shut down when in a ‘low power’ mode to save juice and are only reactivated on power cycling. Delivery receipts can be requested upon successful delivery.”

This is an area to watch closely, potentially offering a cost-effective alternative to dedicated pagers and as 4G and later 5G networks achieve high levels of coverage.

Into orbit: Global Data Burst satellite paging
An interesting alternative for critical paging is the use of satellites. Back in the late 1990s, Motorola launched the Iridium service, which was originally intended for public use but was quickly overwhelmed by terrestrial cellular’s smaller and cheaper phones. Motorola sold the business but it has found its place as a communication service with global coverage for specialist users. Explorers, aid agencies and military are just some examples of users for this technology, which is now being updated with new satellites.

Global Data Burst (GDB) is a new company offering a paging solution over Iridium. Trevor Drawbridge worked with the RNLI when it established its POCSAG network and he set up GDB with partners as he could see a space in the market. He says: “We are being approached by a significant number of potential users and are in production with the pager and repeater, with orders in hand. This technology is an ideal back-up service for blue-light organisations, it has unrivalled coverage and availability. It always works. I can see that the UK, for example, could use this as a complement to the Emergency Services Network.” GDB also offers a signal booster to extend indoor coverage.

Drawbridge describes how GDB’s forthcoming repeater service could work. “The repeater links to the Iridium satellites to connect a local POCSAG network into the rest of the planet. This would enable a team at a remote location such as a refugee camp or a disaster to be contactable from their home control location or headquarters.”

The answer to the question “Which pager technology should I use?” clearly depends on whom you ask. There are strong adherents for both POCSAG and TETRA as the technology of choice, and we’re watching the race between the two that is taking place in Germany with interest. In other countries the existing networks will be a major factor. POCSAG is still widely used and deployed, and suppliers are developing new devices with two-way capability and links to accessories and body sensors to offer additional functions and safety features. Geolocation adds greatly to the capability.

TETRA pagers are an option for alerting, with built-in two-way capability and high levels of security and location, as well as ease of integration in the control room. Mobile phones are also an option, now available with back-office control solutions. Specialist users can take advantage of satellite paging when working in remote situations.

The best advice is to be clear about the system and user requirements before engaging with any one supplier, and keep an open mind about which technology to choose. Engaging with the public safety agencies in nations such as Belgium and the Netherlands where pagers are used alongside TETRA could also be beneficial.

Author: Richard Martin