KITSUNE (Kyutech standardized bus Imaging Technology System Utilizing Networking and Electron content measurements) was a JAXA nanosatellite developed by the HAK consortium, which consists of Haradaseiki Kogyo, Addnics Corporation, and Kyushu Institute of Technology (Kyutech).

[2][4] KITSUNE conducted several missions while in orbit, including observing Earth with a resolution of 5 m, and communicating in C band.

[8] In the SPATIUM-II (SPATIUM : Space Precision Atomic-clock TIming Utility Mission) mission, a UHF signal would be sent from ground stations, and KITSUNE's on board software-defined radio and Raspberry Pi computer would calculate the signal delay time.

From the signal delay time, the integral value of the charge density between the satellite and ground station (total electron content) could be calculated.

The SPATIUM-II mission aimed to demonstrate detecting signal delay time by an accuracy of 100 nanoseconds.