Exploring mesh networks as a facilitator of cross-domain tactical communications

This article first appeared in the June 2022 edition of Global Defence Technology online magazine.

Tactical communications technology must facilitate interoperability, but legacy systems and technological limitations create challenges in the implementation of reliable cross-domain communications. Macy Summers, president of Blu Wireless, explores the potential of mesh networks as one potential solution.

The ability to share data and battlefield intelligence between a nation’s military services is vital to enabling effective tactical communications. It is also important that this data can be shared across command and control (C2) structures, from those in the field and those in fixed C2 facilities.

Yet over the years, different types of technology and systems for sharing information have developed within the forces specific to the needs and requirements of each service. These systems are often incompatible, making it difficult to share data between the different domains directly – such as between air and sea.

Data-intensive applications cause issues for legacy technology

Often the technology and networks that are used within the forces were initially developed for low levels of data use. This means the available technology and bandwidth is no longer appropriate for today’s massive data usage involving video footage, high-definition sensor data and mega-pixel imagery. These legacy systems and siloed ways of working pose a complex challenge when looking to ensure overwhelming military advantage with near-peer adversaries. The UK Ministry of Defence, through its Land Environment Tactical Communications and Information Systems (LE TacCIS) programme, aims to deliver tactical military communications via the TRINITY sub-programme. Similarly, The US Department of Defense, through its Joint All-Domain Command and Control (JADC2) initiative, is also working to overcome these challenges.JADC2 aims to enable a more resilient communications network that will ensure its military is quicker to respond to threats. JADC2 also wants to ensure a co-ordinated approach that will enable data-sharing across the military services, while ensuring parity of access to information and reliable communications across command and control structures. In a similar way, the Morpheus programme (also part of LE TacCIS) will deliver new technology so that soldiers on the frontline can more easily share large quantities of data and updates with headquarters and vice-versa. The programme also aims to ensure easy information sharing between different domains and implement autonomous formations of land, air and naval platforms.

Data-sharing across forces vital for tactical advantage

However, the reality is that the integration of data from electronic weapons, sensors, and online is incredibly complex. To ensure commanders can communicate through a fully integrated system, it is vital that data can be shared in a variety of different formats. Any new systems and technology must also be able to communicate with the current platforms already in place, but this in itself is a challenge. For tactical data to be shared across multiple platforms, the technology available needs to be capable of managing the needs of those operating in a range of complex environments. It must work for soldiers navigating difficult terrain in the Middle East, to pilots who need up-to-the-minute surveillance data and information from the ground, to those operating naval vehicles. This requires vastly increased bandwidth over today’s sub-6GHz radios and resilient wireless networks capable of interconnecting from land to sea to space. The use of satellite systems, particularly low Earth orbit (LEO) satellites, is one part of the answer to these issues. Because they are low orbit, latency is improved compared to the use of geo-stationary satellites. However, to operate with high availability and efficiency, LEO satellites require sophisticated tracking antennas as well as a low size, weight and power profile. LEO communications aren’t generally peer-to-peer, so a hop through a terrestrial earth station (or a space-based relay) is often needed. LEOs are also bandwidth limited compared to terrestrial communications. Therefore, in many ways LEO satellites do not meet all the connectivity requirements for universal complex environments.

How mesh networks provide a tactical advantage

Terrestrial mmWave mesh networks are proving to be a key element in providing resilient networking at the tactical edge. Mesh networks are made up of multiple points called ‘nodes’. These nodes are wireless radio devices that communicate with one another, creating an overlapping mesh that does not rely on a central hub. This allows for quick and efficient data routing. Nodes are self-sufficient and self-managed, finding the fastest and most reliable paths. Mesh networks are built to connect multiple systems, working in tandem with existing technologies, to create a holistic system that delivers reliable transmission of massive amounts of data. They can provide gigabit bandwidths (up to 3Gbps per link today, growing to 30+ Gigabits in the near future) while providing a very small electronic signature – a key near-peer requirement. However, mmWave networks are limited to line of sight and only a few kilometres of range. Mesh networking, also known as ‘daisy chain’ extensions, can extend that range substantially but will not solve the wide-area LAN (WLAN) interconnectivity issue that is so critical in C2.Connected to a LEO WLAN, mmWave mesh networks can connect a peer-to-peer tactical edge network to higher echelon C2 (fibre optic) networks. A wide-band, fully interoperable solution is envisioned that can provide end-to-end strategic and tactical connectivity while operating with critical low probability of intercept/low probability of detection and anti-jam features. Furthermore, peer-to-peer dynamic mesh networks will enable the tactical integration of multi spectral sensor data from multiple sources in real time, as per the vision outlined by JADC2.

Undisrupted gigabit communications links between vehicles

IEEE 5G mmWave-based systems are emerging as the secure and stealthy solution to address the needs of tactical communications. They utilise distributed, peer-to-peer mesh networks rather than a centralised core network, which means there is no single point of failure. Not only can 5G mmWave technology link crewed or uncrewed weapons platforms, command posts, ISR and C2 with the edge, it also allows for defence departments’ pass-through IT governance, cybersecurity, management and data rules. A recent trial of 5G mmWave systems saw this technology interfaced with the networking systems of land vehicles. This setup was then tested in a variety of simulated battlefield scenarios. The technology can provide 360-degree communications coverage via mesh networking to effectively deliver undisrupted gigabit communications links between vehicles. This mesh network was tested in a range of environmental conditions, from congested areas with multiple obstacles to rocky and undulating terrain and to high-speed chases. Even under these difficult conditions, tests showed that the system was able to maintain a reliable and secure communications network. Military services across the globe are looking for reliable solutions to communications and data-sharing in complex operating environments. The ability for different military forces to be able to share data with each other will ensure tactical advantage. There are solutions available that can help answer these issues, and IEEE 5G mmWave mesh networks should be a key consideration.