Transition to Hybrid Critical Communications Networks

There has been much talk amongst critical communications users about LTE networks, broadband capability and an evolution of devices, networks and functionality. A number of mines in Australia are already trialling such systems, and are seriously considering switching platforms in the medium term.

But what advantages does a broadband network offer to critical communications users above those solutions that are already in place? And how can organisations ensure that they will receive a continuous Quality of Service if they look to transition?

In this article, leading figures from the critical comms industry answer the key questions facing organisations looking to implement broadband solutions. Ronan Rafferty is Country Manager for Australia at Sepura, a long-time manufacturer of both TETRA and LTE solutions, with a strong market presence in the Australian mining market. Murray Wales is Principal Consultant and Solution Architect at DXC Technology – Connect, with many years’ experience in designing and implementing critical communications solutions. Finally, Keven Graham is CEO of The Critical Communications Association, the professional body for all critical communications users.

What is an LTE or broadband critical communications solution?

Ronan Rafferty: Mission-critical communications rely on dedicated Land Mobile Radio (LMR) networks to provide a high grade of service for availability, reliability and security. In the last twenty years or so, these have predominantly been based on the TETRA standard, providing narrowband voice and data services to frontline mobile and office users.

There is now increasing interest from these users for data services such as video which require high-speed data and broadband connectivity to complement their narrowband communications. Typically, these can be provided by Wi-Fi or 4G/5G LTE networks, although these are not yet capable of providing an equivalent service for mission-critical voice, which guarantees that communication is always available when it’s needed.

Why is the critical comms industry looking to move toward LTE solutions?

Murray Wales: In mining and Oil and Gas, LTE has already been deployed across onshore and offshore oil and fields, and open cut mines, whilst some mines have completed successful proof of concepts with LTE. These industries require both broadband data for autonomous operations video, telemetry and SCADA, as well as critical voice. The business needs broadband mobile data and mission-critical voice.

Ronan Rafferty: The increased bandwidth of LTE allows for the advancement in safety applications such as personal monitoring, video stream and secure incident feed backup. Other opportunities include vehicle automation, increased interoperability of devices and other IoT functions.

Kevin Graham: While some users have embarked on a strategy to migrate from narrowband to broadband over a managed transition period, other critical users are looking for a hybrid strategy. The motivation for both is to leverage much higher data transfer payloads than can be supported in narrowband networks.

What are the advantages of LTE over existing LMR solutions?

Kevin Graham: Primarily big data, plus 5G ultralow data latency, enabling a device to support mission-critical video and data.

Ronan Rafferty: The emergence of mission-critical broadband will ultimately improve operational tasks by bringing more data to the field user. This drives the mobilisation of existing applications such as database queries and analytics. As an example, users in the field can use smart devices such as tablets, smartphones, laptops and body worn cameras.

Murray Wales: My experience is that where there is broadband coverage over an operational site, applications come out of the woodwork. Examples include the wider IoT family, as well as worker efficiency (for example Time on Tools efficiency or Automated Dispatch), but also covering safety (location, operational awareness), video streaming for instruction or surveillance and the expanded use of Remote Operation Centres.

Can users expect to match or exceed their existing service from an LTE or hybrid solution?

Murray Wales: LTE being deployed in higher frequencies logically means more base stations with be required to provide the same coverage — and they’re not cheap. 5G tends to be available in higher frequencies allowing greater bandwidth, but this is in smaller areas.

Initial private LTE deployments included minimal or no redundancy and were not designed for voice but were specifically designed and deployed around the application data requirements of fleet management and autonomous haulage and drills — this is an altogether different application data profile requirement to mission-critical voice. The future, next-generation deployments of private LTE will be designed from the ground up with PTT voice as a critical application. [In the short term] a hybrid ruggedised device with a digital radio incorporated would be a very workable option.

Kevin Graham: All stakeholders need to understand that the passage from commercial-grade LTE to MCX grade capability will take time just as was the case with digital narrowband services.

Ronan Rafferty: Current mission-critical users want the same features from LTE broadband networks as they can currently achieve with TETRA or DMR networks, with the increased benefit of LTE data. This would include instant PTT communications, extended coverage, choice of availability, secure encryption, and so on. To achieve this, users in the foreseeable future will need to rely on hybrid solutions. Until such as LTE broadband networks are proven to be truly mission critical, TETRA, DMR and other platforms will be the only globally proven mission-critical standards available to LMR users. Only when these standards are achieved will it make economic sense to transfer services from the existing narrowband voice and data networks and these become time expired.

Murray Wales: As a consultant currently engaged by customers across open cut mining and some of Australia’s biggest ports, new TETRA deployments are still the recommended and approved critical comms voice technology.

Which industries would benefit from the additional features that LTE provides?

Ronan Rafferty: Potential users would include pretty much all users who have a thirst and desire for more data to aid in the efficiency of their industry. This could include transport organisations, underground, metro and mainline rail systems, airports, ports, utilities plants, mining organisations and oil and gas plants.

Kevin Graham: All critical industries, including government and public safety and mission-critical transport and utility organisations, would find value in the additional data capability provided by LTE.

What are the reasons to be cautious about LTE networks for mission-critical communications?

Ronan Rafferty: It is vital that the standards around mission-critical voice over LTE are hardened to include availability, robustness of devices, coverage, direct mode operation, pre-emption, priority calls, low latency, and more.

The networks are typically run commercially, and this means they are subject to the same issues as commercial networks — specifically coverage and availability. Without significant investment, particularly in rural areas, commercial networks may not be able to provide the required level of reliability and availability to support critical communications; during a significant emergency, network congestion could consider first responders’ ability to effectively co-coordinate their response.

Murray Wales: The levels of redundancy and single points of failure need to be considered in the LTE architecture. Until this is resolved, TETRA networks are still being designed and deployed over the next few years with organisations still expecting a ten-year return on investment. There is likely to be an extended parallel transition with bridged talkgroups while standards are hardened and agreed, but many organisations are designing their next LTE upgrades to support PTT over LTE.

Sepura have extensive experience of providing mission-critical solutions to users in the mining, transport, utility and public safety markets. To discuss how a hybrid solution could help your organisation, visit www.sepura.com or email sales@sepura.com.

Image credit: iStock.com/marrio31