Delfi-C3 houses two analog sun sensors (located at opposite sides of the satellite) which are fully autonomous and wireless. With the typical internal volume of a nanosatellite already being quite limited, reducing wiring is an important challenge. The sensors will have a half-sized GaAs solar cell as an independent power supply. This autonomy is accompanied by a wireless radio frequency link. This link is an adapted commercial off-the-shelf transceiver, operating in the 915 MHz band.

Although wireless data communication on board such small satellites might seem a bit superfluous in itself, implementing this technology adds to modularity and results in a flexible “plug and play” system. The autonomous sensor unit, in this case measuring approximately 60x40x20 mm, is a predecessor of an even smaller digital version that can be mounted on e.g. a solar panel.

The in orbit experiment will concentrate on demonstrating the feasibility of the wireless link (immunity for disturbances; no interference with other equipment) and the operation of the sun sensor under variable power supply.