Photodiode Placement: Position the photodiode module so it collects reflected or transmitted light from the scanning spot. Depending on whether reflection-mode or transmission-mode imaging is desired, ...

He put it all together on proto-board, although soldering the FM radio module was a bit tricky. The Arduino code is quite simple, and available for download (zip file).

Abstract: We demonstrate a high-power and high-linearity photodiode module based on a 1×4 MMI-Splitter and a 4×PD-Array. The module achieved 10 dBm output power at 10 GHz and an OIP3 of >20 dBm at 20 ...