Talk is not cheap, or simple, in combat
Military adoption of commercial Wi-Fi and 3G/4G network technology ought to be straightforward. Systems are highly capable, there is very little time lag between technology development and deployment, and the high volume of civilian sales reduces costs and risk. Throw in some encryption and a bit of ruggedization, and surely you can turn the iPhones and Android tablets of today into the battlefield communications platforms of tomorrow.
But it is more complicated than that. Greg Moore, business sector manager in the Special Military Products division at Roke Manor Research, the British sensor and communications specialist, says the key challenge is spectrum management.
Well-defined commercial standards and regulation have had the effect of pushing military systems out of civilian spectrum ranges, meaning commercial technology has to be modified to work in military frequency bands, which will often end up eliminating any benefits in terms of the time and money taken to field products. But if military systems move into commercial frequency ranges, an overloaded spectrum is subject to interference and communications become unreliable.
Perhaps counter-intuitively, the problem is, if anything, amplified when the military network is being established in a place like Afghanistan, where domestic network infrastructure is limited—and in a counter-insurgency conflict where the adversary seeks to blend in with the general population.
“The adversary is likely to use commercial systems for communications, or for applications they may wish to use for triggering devices,” suggests Moore. “So, naturally, you're going to want to prevent them from communicating on commercial frequencies. That causes you a problem if you want to deny them the use of the same commercial bands you're using to communicate as well.”
The other key issue Roke has identified is mobility. Wireless fidelity, or Wi-Fi, and cellular networks rely on base stations, which are generally fixed, because they draw power from large generators or electricity mains. Because each base station is linked to its neighbors directionally, network integrity depends on each station knowing where the others are located at all times.
“What we've looked at is whether you can deliver some of the functionality you get from a base station in a smaller form factor, that will allow you to move about the battlefield at reduced power consumption,” he says.
The result is Battlefield Connect, a demonstration system based on technologies developed for femtocell base stations. About the size of a domestic broadband router, these devices use Wi-Fi to deliver very localized cellphone network connectivity. “That has allowed the miniaturization of a lot of the technology you'd find on a typical [cellular] base station with a mast,” says Moore. “But [femtocell] ranges are typically measured in tens of meters, [as opposed to] the 10- or 20-km performance you get from the big base station.”
The hand-portable base station has provided a 3G network with a 40-km (25- mi.) range, and has been capable of maintaining network provision even when the unit is moving in a vehicle at speeds of up to 120 kph (75 mph). In theory, it could be installed on a fleet of ground vehicles, and onboard UAVs, providing network availability and communications between a series of moving platforms.
The Battlefield Connect system is intended to prove the viability of Roke's proposed technical and operational proposals. It was developed with internal company funding, but Roke has been using it as part of a number of U.K. defense ministry research programs, “to help answer questions and explore problems,” Moore says. “They have acknowledged the benefits but want to have questions answered about some of the potential pitfalls, and make sure we're developing technical solutions to overcome those.”
Another technology from the commercial world with promise of military utility is the concept of self-organizing networks. “On the battlefield everything is much more chaotic and unpredictable,” Moore says. “What a self-organizing network is able to do is to adjust power and frequency use without significant user intervention, based on what other base stations around them are doing. The network could change itself if a base station moved, or even if a base station got taken out it would be able to rebalance the other nodes in the network to ensure coverage.
“I think—and this is my personal view —that at the moment, a lot of defense departments around the world are still trying to understand the requirements and exactly how they want to use the technology.”
The barriers to fielding successful solutions may end up having more to do with politics and institutional cultures than technology.
“Is the procurement culture really set up to be able to move with the technology?” Moore ponders. “If you can't move with the technology you end up being stuck in an obsolescence issue, where you're trying to support a version of the standard that really isn't the cutting edge any more. I think this is the fundamental problem: It's just such a different way of thinking about things that, understandably, there's a degree of trepidation before people commit to the technology.”
So, rather than focusing solely on the technology and leaving the user base to fall in line, the company is examining this challenge, too.
“One of the things that Roke is exploring is, are there solutions we can provide as an applique to commercial networks?” Moore says. “In effect, to say, 'Well, you buy the core commercial technology, you add something on top, and that provides you with some of the protection against some of the concerns you have. But when you look at commercial and military technology you're trying to bring two different procurement cultures and business models together.”
Israeli companies are offering militarized commercial-off-the-shelf (COTS) solutions that could complement or (for export) partly substitute the IDF's sophisticated Digital Army Program (DAP, also known as Zayad). Developed by prime contractor, Zayad has improved operational flexibility, coordination and combat efficiency at all combat levels, while reducing the scourge of friendly fire.
Zayad was designed as an evolving system that could accommodate enhancements including information sharing, accessibility, cross-network connectivity and broadband communications. However, the fact that legacy radio systems will remain for decades necessitates the use of several levels of communications—all capable of maintaining connectivity and redundancy under battlefield conditions, such as adverse weather, natural or man-made interference, or hostile electronic attack.
Central to meeting this challenge is software-defined radio (SDR). Elbit Systems subsidiary Tadiran has responded by developing the SDR-7200 radio, a family of vehicular and man-portable digital radios that flexibly support different users with broadband, voice and data, while matching legacy waveforms when needed. These sets enable the army to enhance some networks without replacing all legacy radio systems.
Two Israeli companies, meanwhile, are developing networks based on a “militarized commercial standard” that could complement Zayad. Rafael, the broadband network subcontractor for Zayad, has developed TacMAX, employing the latest WiMax (8.2.16e) commercial standard, which is likely to support the system in future generations. The TacMAX includes a family of base stations, repeater stations and mobile stations capable of delivering high-quality video, data and voice. TacMAX uses the 700-mhz band, which allows it to work with fewer base stations, covering larger cells, compared to other Wi-Fi systems that work in the 2.1-2.5-ghz waveband.
Rafael is designing TacMAX to be rapidly deployable, supporting division and brigade level communications with broadband data networking, as well as providing broadband connectivity for coastal and border security networks. The system can also be used to enhance service for current mobile subscribers requiring ultra-high data rates.
-Elta is offering an alternative militarized COTS solution, based on the Fourth-Generation Long-Term Evolution (4G/LTE) communications standard and aimed at air, land, fire control and naval forces. The land-networking segment operates as a stand-alone system designated TAC4G, providing full broadband networking for land and low-level manned and unmanned aircraft, unmanned ground vehicles and unattended sensors. The system is designed to support users moving at up to 350 kph.
A different application, known as C3Strike, provides a unique segment supporting command, control and communications dedicated for precision attack and guided weapons. Elta Systems considered WiMax but opted for 4G/LTE for its better flexibility and support of maneuvering forces.
Elta adds advanced security layers—encryption, information protection and cyber defense—to the basic 4G/LTE standard. The company says that an important advantage of the 4G/LTE standard is that a military user could exploit commercial infrastructure to deploy its secure networks. Like commercial 4G/LTE networks, TAC4G will support smartphones, handsets and video, transferring up to 150 mbps back and forth. Elta Systems has already developed an Android-based, ruggedized user set which could use 4G/LTE modems to carry secure, protected communications.