Rectified Gaussian noise estimation and its use in position sensitive detection systems

Abstract

Noise estimation of an amplified sensor output is essential for not only operating the position sensitive detection (PSD) system efficiently but also for improving accuracy. The noise can vary from device to device and depends on the operating environment; thus, its estimation should be conducted in real time. However, the rectified noise owing to the limited dynamic range of the analogue-to-digital converter makes this estimation challenging. This Letter presents the use of noise parameter estimation, such as non-uniform offset compensation, detection threshold calculation, and variance estimation of a beam's estimated angular position in PSD systems. Moreover, the estimation of rectified Gaussian noise parameters is proposed. Experiments with the implemented PSD system verify the performance of the proposed estimation method for the rectified Gaussian noise characteristics and the offset compensation method for the estimated beam position.