Kinjiro Okabe

[3] While Hull had published on the HF magnetron years earlier, it was only after Okabe's detailed paper on generation at 17 cm that this device gained world interest.

Commonly called the Yagi–Uda antenna, this was soon used by Yagi, Okabe, and Uda in demonstrating a 40-cm microwave system with a magnetron and wave projector that achieved a transmission distance of about 1 km.

Okabe accompanied Yagi to Osaka and continued his research on magnetrons, ultimately making a split-anode device that generated oscillations at wavelengths down to about 12 cm (2.5 GHz).

Funding was provided to the Osaka Laboratory for experimental investigation of this technique; Kinjiro Okabe was assigned to lead the effort.

Okabe developed an experimental apparatus using a VHF transmitter and receiver with Yagi-Uda antennas separated some distance.

[6] The funding for Okabe's target detection project was not continued; the top levels of the Imperial Navy believed that any advantage of using radio for this purpose were greatly outweighed by enemy intercept and disclosure of the sender's presence.

The 1944 Order of Culture award for significant advancements in science and technology was presented to Okabe by the Emperor of Japan in recognition of his early efforts.