https://www.cse.wustl.edu/~jain/cse567-11/ftp/imgsens/index.html

https://en.wikipedia.org/wiki/Shot_noise

http://www.analog.com/en/analog-dialogue/articles/understanding-how-amplifier-noise-contributes.html

https://en.wikipedia.org/wiki/Signal-to-noise_ratio

https://en.wikipedia.org/wiki/Noise_figure