Abstract: In an embodiment, an antenna is disclosed. The antenna comprises: a substrate of dielectric material, the substrate being substantially planar and defining a first surface and a second surface opposed to the first surface; an electrically conductive ground plane on the first surface, the ground plane defining a slot; a first feed line configured to receive a first input signal having a frequency within an operating frequency range, the first feed line extending over the slot on the second surface in a first direction by a length of between 0.3 and 0.

Abstract: A microwave imaging device comprising a conductive enclosure defining an imaging region within it and an array of wideband resonators, each resonator located substantially in a plane defined by the conductive enclosure.

Abstract: In an embodiment, an antenna is disclosed. The antenna comprises: a substrate of dielectric material, the substrate being substantially planar and defining a first surface and a second surface opposed to the first surface; an electrically conductive ground plane on the first surface, the ground plane defining a slot; a first feed line configured to receive a first input signal having a frequency within an operating frequency range, the first feed line extending over the slot on the second surface in a first direction by a length of between 0.3 and 0.

Abstract: A system for analysing data from a microwave inverse scattering imaging apparatus, said system comprising a processor which is configured to: process data derived from radiation scattered by an object under test by performing a reconstruction process, said reconstruction process being configured to reconstruct the material properties of the object under test by constructing a numerical mode! to fit said data and updating said numerical model in an iterative manner, the processor being further configured to process data concerning information about a feature of interest within the object under test and adapt the reconstruction process by weighting data derived from the scattered radiation on the basis of said information, wherein the weighting selected for a current iteration of the reconstruction process is dependent on the outcome of an earlier iteration.

Abstract: A method of measuring the contents of a search volume.

Abstract: A system for investigating the internal structure of a human or animal body. The system comprises one or more antennas for transmitting and/or receiving electromagnetic energy into or from the body, each antenna comprising a slot formed in a conductive element, the slot having an external boundary defined by a substantially closed internal edge of the conductive element. A receiver is configured to detect the effect of the body on the passage of the electromagnetic energy by recording one or more signals. A processor is configured to process the signal(s) in order to generate an output indicative of the internal structure of the body. The antenna slot is a continuous slot with no internal boundary, the boundary of the slot being completely defined by the internal edge of the conductive element. Each antenna may further comprise two or more conductive feed lines, each feed line coupling energy to and/or from a respective part of the slot.

Abstract: A method of measuring the contents of a search volume.