Plethora of communications options compound challenges at the tactical edge

With comprehensive situational awareness the goal, the Defense Department is constantly seeking and evaluating new combat radios and other wireless communications systems, looking for technologies that offer cost savings, wide coverage, interoperability, and maximum size, weight and power (SWaP) benefits.

Yet as the search for effective systems continues, shrinking budgets, rapid technology turnover and a bewildering array of new communication modes are challenging DOD’s effort to equip troops and their leaders with the best possible situational awareness capabilities. "Certainly times are changing, and budgets are shrinking," said Capt. Joe Matkins, C4 branch head of the Marine Corps Warfighting Lab's technology division, based in Quantico, Va.

Matkins noted that the Warfighting Lab, like its counterparts throughout DOD, is constantly working to be more efficient and effective. "Primarily, we need to meet the ever-growing information security requirements while attempting to address warfighting capability gaps that adversely impact our operations overseas."

Coping With Change

Matkins says that one of the biggest challenges he faces is evaluating a stream of different commercial off the shelf technology (COTS) communications technologies that fail to meet even minimal military standards for ruggedization and encryption. "Based upon our recent testing, we have found that most commercial off-the-shelf technology does not take into consideration Information Assurance (IA) or Certification and Accreditation (C&A) requirements," he explained. "Although they may seem technologically promising, current policy prohibits their use for official unclassified or classified information exchange on the equivalent networks."

Current acceptance requirements are both specific and demanding, Matkins said. "Industry products, to be Type I or SAB approved, are required to have a government sponsor and meet specified National Security Agency (NSA) requirements," Matkins observed. "The process can become quite lengthy, and as a result, the technology becomes obsolete before it is fielded."

Perhaps an even more pressing challenge facing both troops and military leaders is maintaining communication and situational awareness capabilities across communications systems using different operating modes, frequencies and technical standards. "There is a growing demand for interoperability," Matkins said. "Regardless of the system, we have to be able to communicate: proprietary software, hardware, and operating characteristics impede our ability to examine and experiment with emerging technology."

"Tactical radios in use by different services, coalition partners or simply using different frequencies cannot interoperate, rendering the radios groups into separate stove-piped communications groups," said Bob Dunn, CEO of PacStar, a tactical communications system vendor located in Portland, Ore. The problem is exacerbated as the services deploy new, advanced radios and waveforms.

An emerging generation of compact, highly integrated tactical radios address this problem by providing support for a variety of different communications technologies and operating modes, eliminating the need for troops to travel with several different types of radios or to use bulky multifunctional, multimode systems.

The PacStar 3700, for example, incorporates integrated IP-interoperability gateways and is designed to give soldiers the ability to carry and deploy a solution supporting the interoperability with as many as six discrete radio networks. The system aims to give even small deployments the flexibility to communicate with other U.S troops or coalition partners using different or legacy radios.

Matkins is looking forward to evaluating even more systems that address interoperability issues. He believes that a new generation of software-defined radios will solve many of today's interoperability headaches. "We see [existing] technology with specific proprietary functionality, different frequency bands using specific modulation equipment for each band or the use of proprietary wave forms," he said. "As a result, we are exploring different ways to overcome the proprietary challenge through the use of servers which will enable communication via applications."

Network in a Box

Wireless Mobile Ad Hoc Networks (MANETS) are rapidly gaining popularity as a situational awareness communications technology due to their rapidly deployable, self-configuring characteristics. MANETS also excel in the field for both voice and data communication due to their ability to function without the assistance of an existing wireless infrastructure. MANETS can be set up as standalone networks or can be connected to external networks, such as the Internet.

MANET applications and deployments present drastically different network connection topologies and, therefore, place different stresses on network designs, said Jeff Harris, vice president of wireless systems for MANET system developer TrellisWare Technologies, based in San Diego.

Conventional network operation in caves or mines, for example, typically creates a line network or “string-of-pearls” topology. Within mountains or below the earth, a single link failure will instantly silence multi-hop communications, leaving users without situational awareness. This is a problem that can be solved by using a self-healing MANET.

Meanwhile, in urban settings, network nodes are often either sparsely distributed or clustered near each other. In dense node distributions, conventional network approaches often fail because they require constant registration and tracking of the network connection topology, such as neighbor tables, routing tables and link state information. Because a MANET has no need for such data, it can provide rapid self-forming and self-healing capabilities with even large numbers or nodes clumped closely together.

"With a MANET that's scalable, I can put 10, 20, 50, 100 or 500 [users] all on that same network," Harris said. "They're all now connected automatically and transparently, no matter how they move around, and that blanket coverage creates a carrier between all those users, and on that carrier you can move a lot of different kinds of data."

Towers in the Sky

Finding a way to expand the communication range of troops on the tactical edge without resorting to bulky, power-thirsty high-wattage radios or large terrestrial or satellite antennas has long perplexed technology planners and researchers.

"Tactical handheld radios today communicate over ranges limited by radio power and antenna performance and type," Dunn said. "Power is typically in the five-watt range ... this typically limits soldiers to communications ranges of a few miles."

An emerging way of enhancing frontline coverage is using an unmanned aircraft system (UAS) as a combination antenna tower and relay station. "[Planners] are looking for ways to extend the functionality of their existing systems to create new capabilities or fulfill existing capability gaps," said Vance King, vice president of tactical unmanned aircraft systems for AAI Unmanned Aircraft Systems in Hunt Valley, Md. "Using existing, omnipresent unmanned aircraft assets to solve larger communications requirements is a perfect example of this."

AAI's FASTCOM technology supplies modular “pods” that can be quickly attached to the wings of a RQ-7 Shadow tactical UAS. King observed the multi-mission payloads can be swapped easily in the field to equip the Shadow for new mission-oriented communication capabilities as the need arises.

The FASTCOM system is designed to provide organic extensions of established battlefield network capabilities, such as Warfighter Information Network-Tactical (WIN-T) or Joint Tactical Radio System (JTRS), into the aerial layer, King said. He noted that bridging the terrestrial layer with the aerial layer can give brigade combat teams far greater situational awareness, communications and collaboration capabilities than available to date.

"FASTCOM is designed to create a secure, mobile 3G/4G communications bubble allowing users voice, data and battlefield network access via commercial smart phones," King said. He notes that AAI is working on expanding the FASTCOM concept to address other mission-critical, expeditionary communications needs, such as on-demand tactical radio connectivity and communications bridging, all focused on integrating the terrestrial layer with aerial layer networks.

Beyond basic situational awareness, FASTCOM's modular payloads can be used to create an expeditionary communications footprint that enables users to configure and provide a variety of voice and data connectivity options, King said. "As conceptualized, users can quickly deliver a variety of communications capabilities into critical locations and austere battlefield environments," he said. "The measure used to quantify improved situational awareness is the increased flexibility with which a commander can deliver the needed network, whether cellular or other, on to the battlefield in the fastest way possible."

Shrinking Satellite Terminals

Satellite communication systems are also evolving to meet the needs of highly mobile troops operating on the tactical edge with limited transportation and support resources. Typical of a new generation of more-mobile satellite earth stations is Ball Aerospace & Technologies' Mobile Multifunction Low-Cost Array (MMLCA) system, a prototype X-band SATCOM On-the-Move (SOTM) phased-array antenna.

The MMLCA terminal, which was demonstrated last August at the Army's Aberdeen Proving Ground in Aberdeen, Md., is a self-contained low-profile antenna system with no rotating parts. The system enables military platforms to reduce the number of necessary antennas, provide better antenna coverage, and lower the overall silhouette of vehicles.

The terminal offers higher reliability in rough maneuvers and a lower-profile design compared to existing dish antennas, said Ryan Jennings, advanced systems manager for phased-array antenna systems for Ball Aerospace in Boulder, Colo. Unlike current Ku-band units, the system is designed to give troops the ability to access both government and commercial satellites. "This system can assist in providing more information to the troops, as well as providing a capability to provide more information to the decision makers behind the front lines," Jennings said.

The system was created for use on a variety of different military combat vehicles and platforms. "Size, weight and prime power are big considerations for these mobile platforms," Jennings said. "They have limited footprints, the need for low profile and[BS1] often suffer from blockage due to all of the other antenna systems and force protection equipment."

Ball Aerospace developed the MMLCA for the Office of Naval Research (ONR) to demonstrate high-data-rate communications with military and commercial satellite systems. The system was developed under ONR’s FORCEnet Future Naval Capabilities program.

Jennings expects satellite terminals to continue improving—and shrinking—over the next few years. "We continually see a push for more information through higher-data-rate links while simultaneously pushing for lower cost and SWAP," he said.