All modern forces depend on unimpeded access to, and use of, the EM spectrum in conducting military operations. Therefore, there is a requirement to gain and maintain an advantage in the electromagnetic spectrum by countering adversary’s systems and protecting one’s own systems. Adversary can disrupt and degrade the navigation systems on precision guided munitions (PGMs) and cause missiles to go off course, as well as suppress a country’s air defense systems through jamming.
Electronic warfare provide means to counter adversary’s systems while protecting one’s own systems through Electronic Attack (EA), Electronic Protection (EP) and Electronic Support (ES). EA is the electronic countermeasure which includes jamming and deception of enemy radars, electro-optic and communication systems. It also includes use of anti-radiation missiles (ARM), electromagnetic pulse (EMP) and directed energy weapons (DEW). Electronic protection (EP) is the ECCM including such measures as emission control (EMCON), communication security (COMSEC) and electromagnetic hardening. Electronic support (ES) includes all actions taken for the purpose of real-time threat reorganization in support of immediate decisions involving EA, EP, weapon avoidance, targeting or other tactical employment of forces e.g. Electronic Intelligence (ELINT) and Communication Intelligence (COMINT).
High frequency communications have been used since the 1930s as a means to communicate beyond line of sight. It uses the ionosphere to bounce signals from one point to another. HF communication plays a key role in military, para-military and civilian applications. Using advanced HF radios, beyond line-of-sight (BLOS) communication can be achieved without the need of expensive satellite communication or cellular communication servers.
HF Frequencies range from ~1.8 MHz – 30MHz. HF’s single greatest value is its ability to provide reliable short AND long range Beyond Line Of Sight (BLOS) communications. It can support Point-Point and P-Multipoint data rates up to ~10kbps w/o relays . HF is generally available, rapidly and readily deployable – requires very little infrastructure and can be made extremely reliable.
However HF communications is also used by terrorists, illegal immigrants, pirates and illegal fishermen, hence there is need for HF Communications intelligence (COMINT) systems that can gather information from these live signals of interest (SOI) and turn them into actionable signals intelligence. COMINT activities are intended to determine details about the communications such as: who the communicating parties are, where those parties are located, the organizational function of the transmitter, time and duration of communication, frequencies and other technical details of note in the transmission, encryption used and whether it can be decrypted.
COMINT systems should have capability to perform fine-resolution detection, location, collection, classification and archiving of SOI. In addition, Lookback Collection visualization, collection and wideband recording enable operators to view the signal detection history of the entire archive, search and filter by signal characteristics including geolocation and extract signals for playback and further analysis.
IAI launches new ELK-7065 mobile sensor for ground and naval applications
Israel Aerospace Industries (IAI) has expanded its compact HF direction-finding (HF) COMINT product line with the introduction of a new ground and naval HF COMINT direction finder (DF), ELK-7065. The new ELK-7065 has been designed to address HF communication monitoring for military, homeland and policing.
Developed by IAI’s subsidiary ELTA Systems, the small-sized mobile sensor can be used for tactical ground HF COMINT missions and naval operations, according to the company. In a company statement, IAI said that the fast-growing use of HF communication has generated increased interest in HF intelligence systems, but existing systems are not practical at the tactical level.
An Elta company source added that this was “the first system of this size that provides a performance like those of the big systems.” He said that the system decrypts digital and analog HF signals, adding that it receives direct waves from a short range and sky waves at ranges of thousands of km The frequency range in which the system operates in is 1.5-30 MHz.
ELK-7065 enables users to create a “reliable electronic order of battle picture and accurate geolocation,” the company added. The HF antenna configuration measures 1.2 m in diameter and is optimised for fixed or mobile tactical ground and naval forces applications IAI said. Furthermore, airborne versions of the system are already installed on several client aircraft and UAVs.
Commenting on the launch, IAI executive vice-president Nissim Hadas said: “This ground-breaking product line has generated keen interest, and has been successfully demonstrated for numerous customers around the world for both symmetric and asymmetric warfare applications.
In addition to the new, compact HF system, the current product line includes airborne systems already installed on several aircrafts and remotely piloted vehicles.
Wideband HF COMINT systems
Recent advances in HF radio and Digital Signal Processing (DSP) technology, along with new U.S. and international regulatory flexibility in spectrum allocation policies, have ushered in a new era for terrestrial-based, long-range communications capabilities. As a result, HF radio is now no longer limited to agonizingly slow 9,600 bps data transfer rates – slower than dial-up modems of the early 1990s. Today, modernized Wideband HF (WBHF) can deliver rates up to 240 kpbs on a 48 kHz wide channel.
ARAMIS is a scalable strategic HF DF and monitoring solution.
ARAMIS is an advanced COMINT system for interception of ground and sky wave communications in the HF frequency band. It allows to monitor, identify, locate and listen any HF transmissions within several thousand of km range.
ARAMIS is based on the latest generation of HF COMINT/DF sensors (TRC 6500), with full HF band digitalization and Super Resolution Direction Finding and monitoring to cope with multiple cochannels signals, providing 100 % probability of interception even on LPI signals.
ARAMIS offers numerous operational benefits:
- Scalable monitoring capacity thanks to the open processing architecture of each station (fixed or mobile)
- Long range coverage up to 6000 km
- Capacity to DF and listen several HF signals in the same channel thanks to Super Resolution algorithm
- Reduced workload of operator with automated monitoring processing
- Accurate bearing and location fixing
- Spatial filtering and fading cancellation
- Automatic real-time Single Site Location (SSL)
- Single or networked sensors operation
TCI Model 9091 Wideband HF COMINT System
The system rapidly acquires and describes any traditional or modern HF signal activity, and subsequently performs detailed analysis of specific signals of interest. The 9091 can carry out this analysis manually or automatically in real time or in delayed (post-facto) mode. The analysis includes detection, location, collection, classification and archiving of signal activities.
Under typical conditions the 9091 system rapidly searches the HF spectrum using extremely fine resolution. When RF energy is detected, the system automatically determines the direction of the energy source and all other important signal parameters. This information is then automatically archived for future analysis and can be simultaneously passed in real time to operator client workstations. The operator at a client workstation tasks the system to find a particular Signal of Interest (SOI) with specific parameters. The system then processes archived or real-time data to find the SOI and its geographic position or location and presents this information to the operator.
The foundation of the 9091 system is high-speed signal search, combined with detection and direction finding obtained by simultaneous, parallel processing of multiple, 2 MHz-wide channels connected to an antenna array. With automatic noise and co-channel interference suppression, the 9091 is capable of performing automatic real-time DF analysis on any type of HF signal. The DF analysis provides transmitter parameters including frequency, direction and/or location, bandwidth, and time of transmission.
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