Microwaves could bring concealed weapons to light

Microwaves could provide a safe new way of finding hidden weapons and buried mines, thanks to UK research.

Scientists are developing a microwave-based technique that can generate high-quality images of hidden objects. The research may lead to the use of microwaves as a safer alternative to X-rays in airport security checks, building searches, landmine detection and other applications.

This leading-edge work is being carried out by a team of engineers and physicists at Northumbria University, with funding from the Engineering and Physical Sciences Research Council (EPSRC).

Detection systems used in the fight against terrorism and other crimes rely on X-ray radiation to penetrate materials and build up an image of what is underneath. However, because X-rays can damage living tissue, considerable precautions need to be taken when using these systems. Microwave radiation, on the other hand, is harmless to humans and has the potential to produce 3-dimensional holographic images of objects concealed from view.

Although technically viable, microwave imaging systems will only see widespread deployment if they can produce results quickly and cheaply. To tackle this key barrier, the innovative technique being developed by the new EPSRC-funded project will comprise a two-stage process. The first involves the use of conventional detectors to measure the 2-dimensional pattern made by the scattering of microwaves when they come into contact with a hidden object. The second stage takes this data and uses computer software to construct a 3-dimensional image from it. The technique aims to avoid the need to use complex “one-stage” equipment that produces images slowly and at considerable expense.

Dr David Smith, from the University’s School of Engineering and Technology, is leading the project. He says: “The technology could be very versatile and suited to use in security, medical and industrial applications. Although we are just at the beginning of this research, our ultimate aim is to offer an alternative, fast 3D microwave imaging technique which can be used across a wide range of disciplines”.