Sumirad - A High-Speed Imaging Millimetre-Wave Radiometer System

The paper describes the recently developed high-speed millimetre-wave imaging radiometer system called SUMIRAD. It is part of an EDA project using a multi-sensor system for ground-based military surveillance purposes. For this application it was necessary to develop a low-cost scanner system providing a frame rate of about 1 Hz at a very large field of view of at least 60°x30°. These challenges are solved by an innovative fully-mechanical scanner principle using two different types of motion to generate a cylindrical raster scan of the designated scenario. Two radiometer receivers operate over a large bandwidth at W band providing sufficient radiometric sensitivity. In addition, compact designed Cassegrain antennas offer a moderate spatial resolution. Based on a compromise at this frequency domain between the penetration depth and the achievable spatial resolution, the radiometer system offers the advantage to detect and localise objects and persons at different ranges and also extents the surveillance capabilities behind non-metallic materials like thin dielectric walls or clothing. In a similar application the system can be considered for enhanced vision on aerial platforms in order to support blind flying, landing, and the detection of dangerous obstacles (e.g. high poles, buildings or trees, power lines, etc.)