Wireless Networks to Link Base Systems

The U.S. Marine Corps soon will make all of its training facilities and weapons ranges network centric. One of the service’s current programs is linking sensors and monitoring equipment into wireless networks that transmit data back to a facility’s backbone network. The capability allows exercises to be managed remotely and saves the expense of installing fixed infrastructure.

The goal of the Wireless Reach-Back (WRB) program is to link existing communications infrastructure to fixed and mobile sensors and ground forces. Managed by the Marine Corps Program Manager for Training Systems in Orlando, Florida, the WRB will be initially installed at the U.S. Marine Corps Air and Ground Combat Center at Twentynine Palms, California.

Currently undergoing full operational testing at Twentynine Palms, the WRB originated from a Marine Corps requirement issued in 2006. The service turned to the U.S. Navy’s Naval Sea Systems Command (NAVSEA) division at Corona, California, to design and develop the equipment. According to Don Gunnell, lead projects engineer at NAVSEA, the WRB was developed in 18 months and underwent initial field-testing and spectrum certification in December 2007.

The Wireless Reach-Back system is a wireless network developed to link sensors and range equipment at the U.S. Marine Corps’ Air and Ground Combat Center at Twentynine Palms, California.

After the WRB is deployed at Twentynine Palms, NAVSEA will work with the Navy and Marine Corps Spectrum Center to provide it to other U.S. Defense Department training and test facilities across the United States and its territories. However, this effort will not begin until operational testing is complete, Gunnell explains. “We’re still probably four months out before expanding use of this technology beyond Twentynine Palms. Once that’s complete, all Defense Department programs will be able to take advantage of the technology,” he says.

NAVSEA developed a low-cost point-to-multipoint system operating in the fixed mobile government-protected frequency band. The WRB provides last-mile access for fixed sensors and range instrumentation transmitting video, voice and data. This information is tied back to the core infrastructure to be distributed across the network.

Core WRB components are a frequency transmitting amplifier (FTA) manufactured by Luxul Wireless and a secure wireless bridge produced by Fortress Technologies. Ruggedized for outdoor operation, the Luxul Shock-WAV FTA transmits standard IEEE 802.11A lower uniband channels, 36 through 64, in the 5-gigahertz band and converts them to 4.4- to 4.6-gigahertz government-fixed/mobile-protected frequency band. Although the government band is much wider, Gunnell explains that the system was optimized to manage this 200-megahertz slot in the spectrum. Once the signal is converted, it is then amplified at 2 watts. “The idea is to give long-distance reach-back to users, range instrumentation and sensors,” he says.

Fortress’ ES520 secure wireless bridge provides network security. The ES520 combines the capabilities of a wireless access point, bridge, Ethernet switch and Federal Information Processing Standards 140-2-validated AES encryption in a small, rugged, weatherized form factor. Gunnell claims that WRB is radio agnostic. As long as the device adheres to the FTA input, he says that it will properly down-convert a frequency, amplify it and send it out over an antenna.

A power injector powers the FTA via a coaxial cable. The WRB system has an outbound port with a short feed to an antenna. The antenna type will vary depending on the link’s location. The system can be deployed in a fixed tower, transportable tripod or on a ground vehicle.

The WRB is designed to be highly scalable. With eight non-overlapping channels, it is capable of covering an entire base or range, such as Twentynine Palms. But Gunnell adds that it can be used wherever point-to-multipoint communications are needed.