On the Achievable Rate and Capacity for a Sample-based Practical Photon-counting Receiver

We investigate the achievable rate and capacity of a non-perfect photon-counting receiver. For case long symbol duration, under on-off keying modulation is investigated based on Kullback-Leibler (KL) divergence Chernoff $\alpha$-divergence. prove tightness derived bounds for large peak power with zero background radiation exponential convergence rate, low order two rate. fixed power, proposed bound gap small positive value respectively. Moreover, we propose an approximation in duration regime, which more accurate compared upper lower medium signal to noise ratio (SNR) regime. that can be sufficiently small, optimal duty cycle are investigated. show approaches continuous Poisson as $T_s=\tau\to0$. The asymptotic analyzed power. Compared capacity, receiver almost lossless loss attenuation given nonzero radiation, converges, while channel linearly increases. above theoretical results extensively validated by numerical results.