System design of a fast W-band line scan camera using a broadband SFCW approach

In this paper the development of a W-band line scan camera for the use in industrial quality control applications is described. In order to achieve a high line scan rate, a DDS-based baseband generation approach is employed to drive multiple pixel clusters. Each cluster comprising four channels is operated in a time-division multiplexed mode. This allows for the channel clusters to be cascaded and enables wide scan lines without causing additional timing or configuration overhead. The novel system approach is based on independent frontend modules enabling transmission and reflection measurements as well as hybrid geometries. Using flexible dielectric waveguides and 3D printed support structures, arbitrary pixel configurations can be realized in space-constrained environments. The scan time of below 2 ms for a scan line of arbitrary width qualifies the system for the use in real time measurements on conveyor belts with speeds exceeding 5 m/s.