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Tactical Radio Extension

Antenna Radio Range Extension

FORAX (Fibre Optic Remote Antenna eXtension) radio communications equipment provides RF over fibre connectivity between radio equipment and its antennas. The products incorporate advanced RF over fibre systems and innovative RF technologies for military, civil, and industrial markets.

These antenna remoting and range extension products can be used to protect Forward Operating Bases (FOB) and personnel. View  full-size image.

Read about improving command centers with antenna remoting using FORAX (PDF). This case study explains why a tactical communicator would install FORAX in their HQ.

A comprehensive range of FORAX products are available as follows.


FORAX-LSFORAX tactical solutions are packaged for rugged field environments.

FORAX-LS provides a long fiber optic connection between almost any communications radio and its antenna. FORAX-LS supports all current VHF, UHF, and L-Band waveforms from 30 to 512MHz, including UHF DAMA MILSATCOM. FORAX-LS’s fiber optic connection affords tremendous flexibility in antenna location plus electrical isolation for the user’s radios. The antenna can be located up to 10 km away while the radio remains conveniently nearby, enhancing the physical security of both the radio and its user.

A FORAX-LS system consists of a Radio Interface Unit (RIU) connected by a single User-supplied optical fiber to a distant Antenna Interface Unit (AIU). Each AIU link provides 2W transmit power across the full 30-512 MHz band to drive a user-supplied RF power amplifier, if necessary. FORAX-LS operates with both 24 Vdc, for convenience in the field, and “universal” AC power.


FORAX-LS Datasheet
FORAX-HARC (High Antennas for Radio Comms) - Overview

FORAX-HARC systems link tactical radios to their antennas high overhead on a tethered aerostat.

FORAX-HARC communication systems put your antennas high overhead on a tethered aerostat or tower top, implementing the aerial layer while the radios remain securely and conveniently on the ground, in the Tactical Operations Center or Command Post. Aerostat-mounted and tower-top FORAX-HARC systems enhance the aerial layer because they:

  • Increase data rates by avoiding an extra network hop
  • Overcome line-of-sight obstacles
  • Extend the range of radio communications
  • Cover “the last tactical mile”

Waveforms currently supported include P2S, Tetra, ANW2, SRW, WNW, cellular systems including UMTS 3G/4G, SINCGARS, and EPLRS.


HARC White Paper
FORAX-HARC-TD (Tethered Drone)

Comms range extension from the HARC-TDHARC-TD provides dramatically improved network and comms range extension for tactical communicators. A lightweight expeditionary system, HARC-TD flies an antenna for your UHF radio as high as 75 m (250 ft) above ground level (AGL) in all weathers, winds of 30 mph, and with a service ceiling of 5500-m (18,000-ft). The HARC-TD drone is small, minimising visual profile when flying, quiet, and safe to handle. The airborne drone is electrically powered via its tether and can fly indefinitely. It has been flown continually during testing for 400 hours (16.5 days) in all weathers.

With HARC-TD’s antenna at 250 feet AGL, comms range increases from ~3 miles to ~18 miles (30 km) over flat ground, increasing the coverage area by a factor of 80!

HARC-TD is optimised for network/data/voice comms with military and civilian radios, both handheld and manpack. HARC-TD currently supports UHF waveforms including SRW, ANW2, P25, TETRA, EPLRS, and FM voice.




HARC-TD White Paper

  • Physically secure, jam-proof UHF connectivity
  • Physically secure, jam-proof Ethernet connectivity
  • Essentially unlimited bandwidth with optional additional wavelengths
  • Low size, weight, power, and cost (SWaP-C)

Optimized for tethered aerial platforms where size and weight are critical, HARC-Tactical connects all communications from the platform to the ground over one single-mode optical fiber in the tether.

HARC-Tactical transports the payload’s data, UHF radio communications, and the platform’s command-and- control signals over an optical link. The link is physically secure, immune to interference, and essentially unlimited in bandwidth. Unsecure, interference-prone, bandwidth-limited, wireless links to your aerial platform are now a thing of the past.

Your aerial payloads can now deliver torrents of data to the ground.

Your aerial platform now has secure command-and-control.

And your high antenna for radio communications (HARC) connects UHF radio networks out to the visible horizon, while your radio stays safely and securely on the ground.

Enable your aerial platform to operate securely while networking out to the horizon.


FORAX-HARC Tactical Datasheet

HTA-Aerostat (Tactical Aerostat Antennas)

HTA-Aerostat VULOS antennaLightweight and rugged, the range of HTA-Aerostat antennas have been optimised for airborne use on weight-constrained aerostat platforms. The antennas are also broadband dipole which means that – unlike heavy monopole antennas designed for trucks and aeroplanes – no ground plane is necessary to deliver near-theoretical all-azimuth gain and low VSWR across the band.

These HTA-Aerostat antennas have been deployed in the U.S. Army’s Persistent Threat Detection System (PTDS) and Persistent Ground Surveillance System (PGSS) aerostat platforms.


Product page


HTA-Aerostat Antenna Range Datasheet


FORAX HARC-MiniIt’s an emergency and you are in the field. Even when you bring along a 100-ft transportable antenna tower, you always want more range for your radios. And now there is a solution for extending that distance: fly an antenna high overhead using HARC-Mini.

HARC-Mini answers the need for a field expedient solution to lofting a radio antenna as high as 500 ft (150 m). With configurations weighing as little as 2.8 lb. (1.25 kg) plus antenna, just add a small balloon — or even a lifting kite — and you are communicating. Communications have good margin out to 25 miles (40 km) from 500 feet over level ground.

Lightweight, modular HARC-Mini antennas are easily changed in the field. The specific antenna you need is snapped on in seconds. Antennas are already available for several frequency bands in the 30-512 MHz range, and antennas up to 2 GHz are imminent.

HARC-Mini is optimized for Half-Duplex (Push-To-Talk) radios operating with any land mobile radio including P25, TETRA, heritage trunking systems, VHF voice, UHF voice, and AM. Various battery sizes and external power options are available, making HARC-Mini universally configurable.

FORAX-HARC Mini Datasheet

FORAX-RM (Rack-Mount)

Modular FORAX-RM systems link radios to their antenna at link distances up to 75km.

Modules exist for almost any communications or data radio in military or industrial use today, plus GPS and specialty receivers used in signal intelligence (SIGINT) applications. Links with high spurious free dynamic range (SFDR) are available for SIGINT applications.

FORAX-RM (rack-mount) modular systems let users mix-and-match any number and type of FORAX™ RF-over-Fiber links, providing the ability to move the antennas up to 75-km away from the radio location.

A FORAX-RM link consists of a radio interface module (RIM) and an Antenna Interface module (AIM). At the radio site, RIMs are mounted in a 19-inch rack-mount chassis and connected by short coaxial cables to each radio’s antenna port. At the antenna site, AIMs are mounted in a 19-inch rack-mount chassis and connected to each antenna with coaxial cables. Each chassis is equipped with redundant hot-swappable AC power supplies. Optionally, an AIU can be housed in a weather-tight, lightning-hardened, pole-mount enclosure or a system can be provided in transit cases equipped for outdoor operation.


FORAX-RM Datasheet

FORAX-DAS (Distributed Antenna System)

FORAX-DAS equipment connects base stations or repeaters to antennas in distant RF “dead zones.”

FORAX-DAS equipment connects base stations or repeaters used in wireless intercom, public safety, and land mobile radio (LMR) systems to antennas in distant RF “dead zones”. It connects VHF/UHF base stations or repeaters used in public safety or industrial radio systems to distant RF “dead zones,” such as building basements, secure facilities, or tunnels, using fiber optic cables to transport the RF signals. Both conventional and trunked radios systems are supported.

FORAX-DAS offers a secure connection that takes advantage of your facility’s existing single mode optical fiber infrastructure. FORAX-DAS eliminates roof penetrations and awkward, lossy coaxial cable runs to outdoor antennas. Coverage in RF dead zones is possible up to 10-km from the base station (longer by special order). Transmit power levels are tailored for your specific installation and band filtering is tailored to your channel assignments.


FORAX-DAS Datasheet

More Information?

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