LTE infrastructure for today's military networks

COTS-based LTE products are cutting costs and increasing connectivity to improve decision cycles on the battlefield.

7Modern Battlespace tactics, techniques, and procedures are changing. Today, more than ever before, one of the most critical factors for military success is a robust, high-throughput mobile communications network. The exchange of information, including voice, video, and data communications among and between units, soldiers, and commanders in the field is key. The speed at which this critical information is passed is of the utmost importance; it can mean the difference between mission success and failure, and life or death. The focus is on today's increasingly digital battlefields - mission success and warfighter safety are dependent upon the robust transmission and timely, tailored sharing of information. Enter LTE.

The critical need for reliable communication in a variety of Aerospace and Defense (A&D) missions, applications, and environments is driving high-level military officials to upgrade outdated and ineffective communications infrastructures with modern Commercial Off-the-Shelf (COTS) technologies, such as Long Term Evolution (LTE) networks. LTE is a must-have technology for effective communications to increase mission effectiveness and save lives.


The United States Department of Defense (DoD) and military organizations worldwide are increasingly moving away from proprietary, one-off, government-unique systems that are expensive to build and maintain in favor of similar, and often more advanced, systems readily available in the commercial marketplace at reduced costs from a variety of vendors. A&D prime contractors can leverage COTS technologies to meet the needs of their military organization customers, while reaping the benefits of COTS. Readily available COTS solutions help speed time to market, are easier to maintain, and offer extended system longevity when compared to proprietary, government-unique systems. In addition, COTS communications technologies, particularly the LTE standards-based architecture, are mature, proven reliable and robust, easily deployable, and scalable.

Why LTE?

LTE, commonly called 4G LTE, is the enabling technology behind high-speed data and communications networks and handheld communications devices such as smartphones, tablets, and laptop computers, and other mobile devices. LTE is a mature, industry-proven technology with years of investment and advancement in the commercial market, and it provides numerous advantages for Battlespace communications. LTE delivers higher speeds and lower latency than competing technologies, such as the recently terminated Joint Tactical Radio System (JTRS). The all-IP network is standards based, allowing the military to take advantage of a large ecosystem of vendors for the radio and core networks.

Figure 1: Commercial LTE technology is quickly outpacing its proprietary counterparts.

COTS solutions and systems based on LTE have proven themselves to be robust, durable, and reliable – reinforcing the A&D community’s desire to harness LTE in industry-standard form factors such as AdvancedTCA (ATCA) and COM Express. This translates to greater part availability, competitive pricing, and interoperability. In addition, A&D contractors can leverage the broad availability of LTE smartphones in the market, replacing the clunky and expensive handsets associated with legacy military networks.

LTE is also fault tolerant, enabling the network to continue operating properly in the event of a failure. With LTE deployed in the field, the loss of a node on the network-centric battlefield will not shut down the entire network. LTE technologies support failover, automatically switching to a redundant or standby hardware component upon the failure of one or more components. Users can swap out failed system components with readily available and inexpensive COTS hardware in the field. Similarly, militaries can quickly and easily scale the LTE communications infrastructure, adding COTS building blocks and expanding capacity on demand and as needed.

Building a Battlespace-ready LTE network: Three main components

Building an LTE network suitable for Battlespace communications is relatively easy given the broad spectrum of capabilities currently available in today’s marketplace. At its core, a Battlespace-ready LTE network boasts three main components: the Radio Access Network (RAN), Evolved Packet Core (EPC), and IP Media Subsystem (IMS).

Figure 2: Overview of LTE network components.

The RAN is the radio access technology that connects devices such as mobile phones, computers, and remotely controlled machines to the Core Network (CN). The LTE RAN, called eNodeB, handles the air/wireless interface and conversion from the User Equipment (UE) to a wired network via an uplink, such as satellite or backhaul. The eNodeB can be deployed in myriad configurations from base to vehicle to soldier.

The EPC is responsible for call routing and switching. It typically resides on a centralized platform, either at a command center or on a mobile platform such as an Unmanned Aerial Vehicle (UAV) collocated with the eNodeB. The deployment location of these LTE functional blocks depends on the military application requirements and communication priorities.

The third component of the LTE network is the IP Media Subsystem (IMS), which is the telecommunications industry standard for delivering and manipulating multimedia applications on the network. The IMS consists of two parts: the Applications Server (AS) responsible for hosting and executing services for the LTE network, and the Media Resource Function (MRF) that provides capabilities such as media mixing. The MRF also provides the computing power for driving continuous-presence 720p HD multi-pane conferencing technology enabled by LTE networks.

Mobile phones and other wireless connected devices are varyingly known as User Equipment (UE), Terminal Equipment (TE), or Mobile Station (MS). RAN functionality is typically provided by a silicon chip residing in both the eNodeB and the UE.

All these components fit together to make a cohesive, end-to-end LTE network that vastly outperforms currently fielded military communications systems, hosting numerous end-user devices. The network-centric Battlespace, in which personnel and equipment are connected on a common, digital network, is the ideal scenario to leverage LTE communications.

LTE: By air, sea, and land

The military can deploy LTE networks in the air, at sea, and on the ground, delivering accurate, timely, and reliable mission-critical information when and where it’s needed most.

In the air, the military can choose between two deployment scenarios to best meet military application requirements and communication priorities. In one scenario, the eNodeB can reside on a UAV flying overhead while the EPC core resides on a centralized platform at the ground-based command center to deliver an ad-hoc communications network. A single EPC can manage several nodes, each on a different UAV, providing near-instant scalability to accommodate larger military units and geographical areas.

In the second scenario, both the eNodeB and EPC can be hosted inside a UAV or larger airborne military platform, delivering a complete LTE communications network on a single aircraft. This combination delivers impressive low-latency, high-bandwidth communications between soldiers as it eliminates latency associated with the satellite link. However, fewer soldiers or video surveillance endpoints can be accommodated.

Figure 3: LTE deployment models.

Soldiers at sea can communicate on a single communications platform ship-wide using smartphones and similar consumer-grade devices they rely on when off-duty. Ship-wide and submarine-wide LTE communications networks based on high-capacity ATCA can support thousands of users as well as Push-To-Talk (PTT) interactivity.

On the battlefield, an LTE network can leverage a small ATCA chassis or Rackmount Server (RMS) to serve as a battlefield communications hub (LTE-in-a-Box) in a Humvee shelter or Tactical Operations Center (TOC) Ground Control Station (GCS). LTE network-enabled TOCs and Humvee shelters increase the flow of information between commanders and personnel on the battlefield, bringing mission-critical communications – including texts, images, and video – to the tactical edge.

Deployed soldiers can also carry compact, lightweight LTE communications nodes on the COM Express form factor in their backpacks, enabling a single soldier to provide all allies in range access to vital network Command, Control, Communications, and Computers Intelligence, Surveillance, and Reconnaissance (C4ISR) resources. As soldiers move in the Battlespace armed with backpack LTE nodes, they are actively expanding the far-reaching, fault-tolerant, mesh network. Soldiers and unmanned vehicles (robots) in the field can also be equipped with the latest in high-tech wearable video equipment coupled with an LTE network to enable real-time, HD and Full-Motion Video (FMV) information dissemination on-the-fly.

LTE in future military missions

Existing military networks are being quickly outpaced by their commercial counterparts. Today’s military personnel are accustomed to using smartphones connected to commercial LTE networks in their personal lives, and they expect the same, if not better, functionality in the field. The general consumer population has greater power, information, and communications capabilities in their hands, via smartphones and tablets, than do deployed soldiers. Deploying LTE technologies can change that equation for the good of current and future military missions.

The time for the military to transition to LTE is now. Capable COTS communications technologies are available from companies such as Radisys and ready to be adapted for rapid insertion into the modern Battlespace and deliver capable communications to warfighters. The battlefield is evolving, and the military can evolve with it by adopting a robust and cost-effective COTS LTE solution. LTE delivers many benefits, including fast speeds, rapid deployment, scalability, technology maturity, low cost, and high reliability. Perhaps most importantly, the LTE standards-based architecture can prove a powerful military tool, enabling rapid response to threats and leading to mission successes and lives saved.

Harry Jensen is Director of Aerospace and Defense at Radisys Corporation.

Jeff Sharpe is Senior Product Marketing Manager, Aerospace and Defense at Radisys Corporation.

Radisys Corporation