Array-based digital sun-sensor design for CubeSat application

Abstract

A Custom-designed, digital sun sensor based on the orthogonal photodiode array is proposed. A well-known application of geometrical aperture mask on light detectors is utilized in a non-conventional design for CubeSat application. The main characteristic of this design is the inclusion of a chirped pattern of slits, while using a digital readout of the photodiode arrays. This pattern is expected to allow greater angle detection accuracy while digital photodiode readout decreases complexity and power consumption. The array-based design approach features low power requirements and simpler readout interface and signal processing when compared to matrix-based approach. The proposed sun sensor design will be demonstrated on DESCENT CubeSat as a part of the technology demonstration payload. The characterization of the prototype sensor shows that the current 5-slit design achieves 0.3-degree accuracy with ±51.5-degree field-of-view (FOV).