Utilizing circular scanning in the CZMIL system

Abstract

In pursuit of increased reliability and improved signal levels, we employ a scanning approach that supports the high frequency acquisition requirements of the system while utilizing a large aperture receiver. A continuously rotating circular scanner was developed using direct inductance drives to rotate a Fresnel prism, acting as synchronized transmitter-receiver optical element with a fixed incident angle to the sea surface. Circular scanning introduces challenges in evaluating the system's coverage. By its nature, a circular scanning pattern introduces non-uniformity. Unlike galvo-based scanners roll and pitch compensation is practically impossible for a large mechanism, therefore careful planning is required to ensure continuous coverage under realistic operational conditions. Selection of optimal operation parameters is discussed as well as different ways to evaluate surface coverage in different operation modes.