Abstract: A method of extracting a radial velocity characteristic of a target from coherent pulse bursts comprising the steps of applying to data a ‘best fit’ model of the echo returns from a target in the presence of clutter to obtain a residue (error) value and minimising the error value by a predetermined method to give the best fit value for the target radial velocity. The method enables more information to be retrieved from coherent bursts than conventional methods and therefore greatly enhances performance of radiation pulse echo detection.

Abstract: A light source system in which light scattered inside a chamber (2) exits from a hole (3) to provide a light output from the system. The interior wall of the chamber (2) consists of a material which is very efficient at scattering incident light. Light emitted from a light source (1) undergoes at least one scattering event within the chamber (2) before escaping from the chamber (2) through the exit hole (3). Any geometrical attributes of the light from the source (1) are removed before the light exists from the chamber (2). The exit hole (3) can have a tube inside (4) and/or outside (5) the chamber (2) for collimating the light output. A mechanical shutter (7, 8) can be used as a simple dimmer mechanism for the light output from the system. The light source (1) can be positioned inside or outside the chamber (2).