EMRS DTC - Electro Magnetic Remote Sensing Defence Technology Centre > Research Programme

RF Systems

TERAHERTZ SENSING

SUMMARY

There is a broad area of the EM spectrum between the upper end of mm-wave radar and the lower end of long wave IR which is currently totally unexploited for military sensing. A major inhibitor has been the difficulty of generating and detecting radiation in this band, but recent developments have started to produce suitable devices. Knowledge of propagation phenomena in this band is sketchy. The objective of this research is to assess the current state-of-the-art and to investigate its potential utility for a range of military sensing purposes.

MILITARY BENEFITS

Sensing in this band could potentially provide some of the traditional advantages of radar sensing, including better weather penetration, together with the higher angular resolution normally associated with EO systems. It also offers the prospect of remote detection of chemical and biological agents.

RESEARCH OBJECTIVE

	To assess the state-of-the-art in THz technology, including close liaison with key researchers in Academia
	To identify capability gaps that may be addressed by THz sensing, both active and passive
	To predict expected performance levels in 5 years' time for range and sensitivity
	To establish a Test Bed facility in collaboration with Industrial and University partners, and to undertake experiments on targets of military interest.
	To identify and develop critical technologies necessary to meet military requirements
	To investigate and develop THz techniques for detecting and/or imaging concealed targets

RESEARCH OUTLINE

TeraHertz sensing is a very new field, existing knowledge being largely limited to the astronomy community. Its potential for military sensing is largely unknown, but there are possibilities that it could offer some of the traditional advantages of EO sensing with much better weather penetration, yet still be within the practical limits of a military platform. Alternatively the technology can be viewed as a very high frequency radar.

The research will review currently available technology for transmission, reception and analysis of electromagnetic radiation in the spectral region between high frequency RF (~100 GHz) and long wavelength IR (~ 12mm). It will also assess current and anticipated technology developments in other fields (e.g. astronomy) that may benefit EM sensing in this spectral region.

The research will review the literature on atmospheric propagation in this spectral region. This will consider operation in clear air in various parts of the world, and degradation in cloud, mist, rain, snow, smoke etc. The objective is to understand the potential capabilities and limitations of sensor operation in this spectral region. It may be that measurements are needed to understand some of these issues, and this will be considered.

Sensing in this spectral region may be viewed from the viewpoint of imaging sensors (similar to imaging IR) or as single element detection (similar to radar). The research will consider potential sensor system design and operation from both viewpoints. It will also consider both active and passive operation, and where active, both coherent and noncoherent operation.

The research will also consider the use of pulsed THz technology as a mechanism for the remote detection of particular molecules, the aim being to establish the feasibility of remote chemical/biohazard detection.

CO-ORDINATION WITH EXISTING / PREVIOUS RESEARCH

This research is novel in its application to military sensing, but will draw on existing academic research in the field.