Fluid Surface Velocity Estimation Using a 77 GHz Radar Module

This paper introduces a surface velocity measurement system for fluids based on a multiple channel radar module using a center frequency of 77 GHz. The system, which is positioned above the stream, relies on a frequency-modulated continuous-wave approach and is capable of determining the distance between the target and the radar module, the angle of arrival of the impinging radio frequency signal, and the target velocity. Thus, disturbing reflections generated by stationary or moving scatterers can be distinguished from the target of interest. The system concept is proven by means of measurements that were performed at a channelized stream.