Fine-Time Resolution Passive RF Source Imaging

Lead Research Organisation: University of Strathclyde
Department Name: Electronic and Electrical Engineering

Abstract

Radio Frequency (RF) sensing and communicating is now ubiquitous. Moreover, with RF emissions being generated using generic semiconductor technologies and with the available spectrum becoming ever more crowded, there is an inexorable convergence of civilian and military systems. Thus all systems are now characterised by frequency, beam-pattern and pulse-pattern agility; because the technology allows it. A radar system will exploit agility to avoid detection and to avoid interference or ambiguity while interleaving multiple service functions whereas communication systems again exploit agility in the search for bandwidth matching varying data rate needs.

Thus the problem of gaining situation awareness, by passively monitoring RF transmissions, is becoming ever more fraught with difficulty. Radar and communications systems are no longer characterised by steady repetitive signal structures and as a result it is difficult to collect enough energy from individual sources to detect them, let alone to characterise or locate them. Thus there is a need to exploit not just the direct line-of-sight signals but also to multi-path reflections of the primary source. Of particular interest is the analysis of finer details in the signals relating to a specific source in order to reconstruct more detailed understanding of the source itself, via what might be described as a source image. Reflected signals will tend to have lower power than the direct interception and it is likely that acceptable performance will require the use of multiple-sensors able to share information and synthetic aperture techniques to gain resolution.

Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/N509760/1 01/10/2016 30/09/2021
1811676 Studentship EP/N509760/1 01/10/2016 31/03/2020 William Thomas Coventry
 
Description Low probability of intercept radar and commutations is a rapidly emerging technology. As the name would suggest, the detection, localisation and characterisation of such an emitter is a difficult task using conventional passive sensing architectures, methods and algorithms, prompting the need for new approaches. One of the key properties of such an emitter is a broad-bandwidth modulation scheme. This award has provided significant advances in the area of direction of arrival (or bearing) estimation of broad-band, low probability of intercept signals via improving computational cost of state of art methods, reducing the number of required antenna elements through the use of sparse (non uniform) linear arrays and the ability to detect correlated signals.
Exploitation Route This advancement of this award will only prompt further open research questions in this field. As such, this work may be further advanced within academia by reducing the overall computational cost, and improved accuracy on polynomial matrix operations, such as the eigenvalue decomposition. In industry, this work may be taken forward for further innovations and extended to a wider range of applications, such as acoustic/audio, sonar and communications applications which broadband array signal processing is an important aspect.
Sectors Aerospace, Defence and Marine,Electronics

 
Description Participation at the EMSIG workshops 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact Attendance of the Electromagnetic Systems Interest Groups workshops. Presentation of the research.
Year(s) Of Engagement Activity 2017,2018,2019
URL https://www.emsig.org.uk