EW Receiver Research Articles

A Novel Method of Radar Antenna Scan Pattern Recognition Using Visibility Graph

Radar antenna scan has a great influence on reconnaissance targets, interference decision-making, and electronic support measures. In this paper, we propose a recognition methods of antenna scan pattern based on visibility graph, including circular scan, sector scan, helical scan, raster scan, conical scan, phased array scan, phased array azimuth scan and circular elevation scan. We have mapped the radar scans pattern, the azimuth and elevation curves of various scan pattern and the signal variation of the EW receiver. Moreover, the related features are extracted from the visibility graph and the seven radar scan patterns are classified by five kinds of classifiers. Simulation experiments verify the efficiency of the algorithm.

Discrete Electronic Warfare Signal Processing using Compressed Sensing Based on Random Modulator Pre-Integrator

Electronic warfare receiver works in the wide electromagnetic spectrum in dense radar signal environment. Current trends in radar systems are ultra wideband and low probability of intercept radar technology. Detection of signals from various radar stations is a concern. Performance and probability of intercept are mainly dependent on high speed ADC technology. The sampling and reconstruction functions have to be optimized to capture incoming signals at the receiver to extract characteristics of the radar signal. The compressive sampling of the input signal with orthonormal base vectors, projecting the basis in the union of subspaces and recovery through convex optimisation techniques is the current traditional approach. Modern trends in signal processing suggest the random modulator pre-integrator (RMPI), which sample the input signal at information rate non-adaptively and recovery by the processing of discrete and finite vectors. Analysis of RMPI theory, application to EW receiver, simulation and recovery of EW receiver signals are discussed.

MSW devices for EW receiver applications

Significant improvements are required in the performance of MSW dispersive delay lines and filter banks before they are ready for systems application. Typically delay lines with bandwidths of 1 GHz or greater, differential delays in the range 200 ns to 1μs, and minimum phase errors (<±1 °) are required for large (∿40 dB) dynamic range compressive receivers. However, techniques are evolving (see rest of this issue) in this relatively new area of technology which will allow systems performance requirements on phase errors to be met. Possible approaches to low phase error dispersive delay lines include reflective arrays, stepped ground planes, and multiple YIG films. The stepped ground plane technique is the most advanced and uses an optimization approach to the delay-line design, which results in a minimum phase error [20]. Ultimately the minimum achievable phase error will be limited by reflections from transducers and multiple mode effects in the delay lines. The MSW compressive receiver requires parallel advances in high-speed digital processing techniques to achieve its full potential.

Magnetostatic Wave Dispersive Delay Line

The physical limits of the interdigital transducer (IDT) implementation for surface acoustic wave (SAW) devices beyond VHF/UHF have restricted their use in microwave systems. Inherent dispersion of magnetostatic wave (MSW) devices is suitable for signal processing directly at microwave frequencies. Dispersion enhancement tests performed on MSW delay fines confirm their suitability to an S-band simultaneous pulse separator for EW receiver applications.