Noise analysis and equalization of a multi-photodiode optical wireless receiver

A technique is presented which improves the performance of an optical receiver for optical wireless communication with a moderate additional complexity. The well-known high-impedance front-end design of an optical receiver is extended by combining multiple PIN photodiode-FET circuits with optimized equalizers in order to achieve a better SNR at the output of the receiver. The receiver is optimum in a sense that it reduces the effective equivalent input referred noise current spectral density by a factor propertional to the number of PIN-FET combinations.