Linear APS-based sun sensor is a kind of sun sensor based on a linear array Active Pixel Sensor (APS) with low power
consumption, small size, and small mass. It is integrated with optical, mechanical and electronic technologies. The main
function of linear APS-based sun sensor is to realize two-axis measurement of solar aspect angle, determining the
attitude of spacecraft. The image of the solar is projected on the linear image sensor through an N-shape aperture in front
of it. By comparing the position shift of solar image projection on linear array APS, we can obtain the position of the sun
relative to sensor. This paper analyzes the sources of system error and some specific solutions are proposed. The error
compensation algorithm in the software designed makes the sun senor meet the accuracy requirements. The performance
characteristics are as follows: FOV is ±64°x±64°; the accuracy of α-axis is better than 0.02° (3σ) in the FOV of less
than 45°, and better than 0.03° (3σ) in other FOV; the accuracy of β-axis is better than 0.03° (3σ) in the whole FOV.
Linear APS-based sun sensor was successfully carried by satellite on orbit in October 2012. On-orbit testing showed that
it operates normally and the data curves prove the accuracy meets requirements.