Communication and information transmission equipment of the US special forces.
International Defense Review.- 1995 .-№5.-P. 41-52.
Communication and information transmission equipment of the US special forces
The EFCS (Electronic Filmless Camera System) from Harris is used to collect and distribute tactical-level video images in the US special forces.. The company recently released a special gateway with a powerful error detection and correction system that allows data and images received from EFCS type systems to be exchanged between different local networks and remote computers using standard military radio stations of classified communication. In addition, the company offers a portable version of its digital image transmission system DViTS(Digital Video Imaging Transmission System), mounted in a hard case, which uses communication protocols designed for signal transmission over narrowband communication channels. The system uses packet transmission, adaptive forward error correction and a procedure for selective automatic request for repeat transmission, which allows maximizing the capacity of channels with degraded characteristics.
Lightweight portable satellite terminal PoST (Portable Satellite Terminal) by GTE Goverment Systemsallows data and image exchange via civil and military satellite lines at speeds of up to 256 kbps. In order to increase the security of communications and simplify the operation of the terminal, transmission with spectrum expansion by means of direct code sequence modulation is used. It allows operation at very low signal power using small antennas (35×45 cm for the field kit), which are easily oriented to the satellite. LYNXX INMARSAT-B transportable satellite communication terminals manufactured by Mobile Satellite Products(formerly ViaSat Technology) began to enter service with US Special Forces in September 1994. Following the successful use of earlier equipment during the 1990-1991 Gulf War, Motorola developed the AN/PRT-10 communications system.. The system simulates the air of two-way radio communication in a tactical radio network. Using a portable computer in dialog mode, the user can set the necessary communication parameters — subscriber load, length and time of sending messages, operating frequencies — in accordance with one or more scenarios. Then, plain text is entered into the device and the scenarios are loaded into simulators weighing approximately 10 kg (without batteries), which are placed on the ground. These simulators communicate with each other according to a given scheme on HF, VHF and LMV. The US Army Research Laboratory is studying the LOTIS-D (Laser Overlay Thermal Imaging System-Digital) systems was developed by SAIC (Science Applications International Corp) under the auspices of the OST organization(Office of Special Technology). It is a hand-held 3-5 µm infrared camera equipped with a 256×256 platinum silicide focal plane array with a frame rate of 60 fps. The system has a laser pointer (wavelength 1.06 µm), a dual-range 200 mm f/2 catadioptric lens, a Stirling engine refrigerator, a digital signal processor, and a power management circuit that reduces power consumption and thereby increases the operating period of the system before recharging. The laser spot on top of the thermal image can be seen through a 12.7 mm sight.
After the abandonment of the ambitious JASORS (Joint Advavced Special Operations Radio System) program, which was led by Harris, Hazeltine proposed the SOTIS system for special forces(Special Operations Team Information System). This system was proposed to replace various radio stations in service with US special forces. It uses multi-band radio technology designed to operate on various Speakeasy communication channels, as well as low-probability-of-detection and low-interception signal transmission technology. It was supposed to create a whole family of radio stations (including hand-held ones) capable of operating in the HF, VHF, UHF and satellite communication ranges.
Currently, a number of companies offer ready-made hand-held radio stations with a low probability of detection and interception, quite suitable for use in special operations. Here we can name the SEM 52-SL equipment by Alcatel SEL, the Cougar 2000 family by Racal Radio, Chameleon SFH-41 by Shadow Technologies and the Penumbra radio station by Magnavox. The Cougar 2000 family of radio equipment includes the PRM 5100 digital personal communication radio stations.ranges of 136-174 MHz and 440-512 MHz, compatible with the Cougar family of radio stations already in service with the British special forces. The radio station provides for the transmission of an encryption key via a radio channel, selective calling, channel scanning and digital encryption. The Shadow SFH-41 radio station weighing 680 g (with batteries) in the frequency tuning mode switches between 1024 channels at a frequency of 50 times per 1 second in the range of 148-174 MHz.
Penumbra hand-held transceiver from West Coast Division of Magnavox Electrinic Systems Companyis equipped with a GPS navigation system receiver. The pseudo-noise modulation used in it ensures a low probability of detection. According to the manufacturer, any scanner can detect a radio transmitter only if it is brought closer to the latter at a distance of no more than 5 m. For example, a regular AM radio station with a communication range of 5 km is detected by a scanner at a distance of more than 30 km, and the equivalent detection range using a broadband radiometer is 12 km relative to the radio horizon. When the push-to-talk button is pressed or when a polling signal is received from another transceiver, the transceiver automatically transmits the identification data of its user, the code and the GPS system data. At the same time, the indicator displays the range and azimuth of the other transceiver, which significantly facilitates the approach and support of friendly forces. In a set with a GPS receiver and batteries, the transceiver weighs 1.4 kg.