Two-way radio systems are the mainstay of airport communications, but push-to-talk (PTT) over cellular solutions now provide a highly flexible add-on allowing radios and cellular smartphones to interconnect, while unified platforms enable operators to combine disparate voice and data systems into a single converged solution

Airports contain many discrete organisations and job roles operating within a very complex environment. These different organisations have to work together efficiently to ensure that the airport’s main job of enabling aircraft to arrive and depart on time is properly organised and runs to schedule.

This can only be achieved if the communications between them are reliable, always available and of a sufficiently high quality. The communications solution must provide adequate radio frequency (RF) coverage across the whole site with no ‘dead’ areas. It must also support roaming voice and data transmissions without losing the signal.

The choice of radio solution depends on how critical the communications are to the business operations. In the case of airports, they are mission critical. Land Mobile Radio (LMR) systems are truly mission critical as they are dedicated networks specifically designed to provide a constant service in any emergency. As they are private networks, the end user has full control over this vital asset.

LMR solutions
An LMR system allows an airport operator to tailor RF coverage and capacity to the exact needs of the airport footprint and the numbers of radio subscribers. Modern digital two-way radio systems, such as Digital Mobile Radio (DMR) or TETRA, also enable multiple redundancy measures to be built in to ensure high levels of network robustness, reliability, availability and security. They are also easily scalable.

DMR provides a range of PTT options including group, individual, broadcast and emergency calling. Group calling means large numbers of people can transmit and receive communications at the same time, thereby improving efficiency and ensuring a fast response to any call to action.

DMR networks also support a range of narrowband data services including short text messages, GPS positioning and tracking, along with worker safety applications such as Man Down and Lone Worker alarms. They can also support a range of business productivity applications such as job tasking and workflow management systems.

Indoor location can be enabled by deploying Bluetooth Low Energy (BLE) beacons, which will connect with BLE units integrated into DMR or TETRA radios. This is particularly useful for monitoring security guard patrols.

Value added applications
It is also possible to integrate alarms into the radio system. If a fire, intruder detection or smart building component alarm is triggered, an alert can be sent directly to the appropriate responders, be it firemen, security guards or facilities management staff, to provide a faster response.

Most major LMR manufacturers offer a range of rugged devices from entry-level to high-end radios supporting a wide range of applications, including specialised noise cancelling technology to aid audio quality in noisy environments and long battery life (16 hours or more). Models include slim, lightweight radios for those who prefer a more discreet, less bulky radio.

Bodycams are another tool that can be used in either standalone mode or paired with DMR or TETRA radios. Some models double as remote speaker microphones and include an emergency call button. The most recent high-end models support not just DMR/TETRA, Wi-Fi and Bluetooth, but also 3G/4G cellular.

This means they can be used to stream live video feeds, which can be useful for security guards among others. Some LMR manufacturers also offer dual mode radios supporting DMR or TETRA and 3G/4G, so users can talk to both LMR and cellular smartphone users with one device.

PoC alternatives
Push-to-Talk over Cellular (PoC) solutions have recently come into their own with the roll-out of nationwide 4G cellular networks, which deliver the speeds and low latency connection times to rival LMR devices. PoC delivers PTT over cellular devices using public mobile phone networks.

PoC should be seen as an amazingly flexible add-on to LMR systems with a smartphone interface that users have been waiting for a long time. The great advantage of PoC is that the user does not have to invest in or maintain any infrastructure. They just need to buy (or hire) the devices, SIM cards and agree a service contract with the PoC platform provider.

The downside of using PoC is that the end user has no control over the network coverage, signal strength or capacity. This is entirely in the hands of the mobile network operators. If the network goes down, there is nothing the end user can do.

PoC supports the same range of call types as LMR and has the advantage of allowing the end user to set up as many call groups as they like, as they are not restricted to a limited number of channels like LMR. The other major benefit of PoC devices is that they also support broadband data services and Internet connectivity. PoC platform providers can deliver enhanced levels of service, including faster connection times, higher priority access to the mobile network and stronger security measures. Some PoC providers offer the addition of LMR-style dispatch services and gateways to interconnect with LMR networks.

A number of LMR vendors have expanded into the PoC space drawing on their expertise in developing rugged devices and understanding of PTT technology to provide software platforms and devices in both traditional two-way radio and smartphone style form factors.

Unified communications
Another more recent trend is the development of unified, or converged communications platforms able to support DMR/TETRA, cellular 3G/4G, PoC, fixed telephony systems, Wi-Fi and both narrowband and broadband data feeds on the same software. Data includes IoT sensor information/alarms, social media feeds, CCTV and other video sources such as drones, vehicle-mounted cameras and bodycams.

This is a huge benefit for somewhere as complex as an airport where several types of communication networks are deployed. When combined with a sophisticated command and control capability, computer-based dispatchers can manage multiple radio modes and data streams as a single user-friendly system. They can co-ordinate everything from a central point be it operational, custodial, ground handling and security alerts, as well as see the whereabouts of personnel and assets visually displayed on maps on a single screen in real time.

Hytera is a leading global provider of professional mobile radio communications, dedicated to bringing the most valued and user-centric solutions to clients across the world. From major events such as the Beijing Olympic Games to oil rigs in the North Sea, Hytera’s professional wireless communications systems are meeting the demands of the modern workforce.