Recent Trends in Antennas for Electronic Warfare Applications

Electronic warfare (EW) is a military technology which facilitates prevention of effective exploitation of electromagnetic spectrum by an adversary, while ensuring its friendly use. It provides early warning of the threats and generates Electronic Order of Battle and thereby helps our Forces in planning appropriate response. Hence, EW is a vital component of the Nation’s security. DLRL has developed technologies and acquired technical competence and capability for configuring the EW Systems to meet the state-of-theart requirement of armed forces in Communication and Non-Communication segments. Non-com EW is electronic warfare in the context of electronic sensor systems, particularly radar while Com EW concerns with battlefield communications systems that support the command-and-control process. The heart of the system in both Com and Non-com segments of EW is the antenna which provides the necessary interface between the transmitter/receiver system and free space. EW Antenna research and development is propelled by the demand for new, high performing electronic systems for electronic support (ES) as well as electronic attack (EA) in both communication and radar frequency bands. To meet this demand, DLRL has successfully designed and developed various types of antenna systems working over frequency range of 1.5 MHz up to 40 GHz. The activity is now not only confined to only defence field. Due to band congestion and the need for frequency spectrum management, attention is focused on new technology areas like smart antenna systems, shared aperture antennas, fractal antennas, etc, and creating higher frequency systems, embracing millimeter, sub-millimeter and quasi-optical radiators. In the recent years, DLRL has designed and developed electronic warfare systems which have high probability of intercept and short reaction time for all threat signals. The lab has attained expertise in design and development of EW antennas and radomes working over 1.5 MHz to 40 GHz for signal detection and analysis, direction finding and jamming applications. These antennas have been developed, productionised and inducted into service. Directional antennas like log periodic, cavity backed spiral, ridged horn, tapered slot are used in amplitude comparison with DF accuracy ~5 rms, phase comparison and time difference of arrival direction finding system with DF accuracy of 1 to 2 rms. For effective and accurate jamming of hostile signals, high gain reflector antennas with fine bearing auto track horns have been developed and employed to handle one target at a time. To counter multi attack warfare scenario, DLRL has successfully developed state-of-the-art Rotman Lensfed multi-beam array antenna which can handle multiple threats. DLRL has developed a large variety of communication antennas covering 1.5 MHz 3 GHz. Electronic beam switching cylindrical array antenna for point-to-multipoint communication is one such example. Different types of monopole, sleeve, discone, log periodic antennas etc. are in use for communication EW applications. These antennas have been designed keeping in view the portability factor also. The present key research in antenna technology includes high performance, low-cost, compact size, lightweight, conformal mounting for low RCS, antenna / electronics integration. Micro electro mechanical systems (MEMS) are used in realization of state-of-the-art reconfigurable electromagnetic structures to perform multiple functions. Computer controlled smart antennas and advances in core technologies such as microelectronics are miniaturizing systems in weight and volume covering a wide frequency range. Present interest in the area of smart structures have led many researchers scurrying to find new and promising application of new smart film materials. In addition, some of the latest trends in the field of antennas like smart antennas, fractal, photonic, multi function shared aperture antennas, Rotman Lens fed planar array and tactical HF antennas, small size omni antennas in VHF/UHF frequency band are also discussed.