Title :
Refined analysis of the Poisson channel in the high-photon-efficiency regime
Author :
Ligong Wang ; Wornell, Gregory W.
Author_Institution :
Dept. EECS, MIT, Cambridge, MA, USA
Abstract :
We study the discrete-time Poisson channel under the constraint that its average input power (in photons per channel use) must not exceed some constant ε. We consider the wideband, high-photon-efficiency extreme where ε approaches zero, and where the channel´s “dark current” approaches zero proportionally with ε. Improving over a previously obtained first-order capacity approximation, we derive a refined approximation which also includes the second-order term. We also show that pulse-position modulation is optimal on this channel up to the second-order term in capacity.
Keywords :
approximation theory; optical communication; optical modulation; pulse position modulation; stochastic processes; dark current approach; discrete-time Poisson channel; first-order capacity approximation; high-photon-efficiency regime; optical communication; pulse-position modulation; second-order term; wideband; Approximation methods; Conferences; Dark current; Information theory; Optical pulses; Photonics; Upper bound;
Conference_Titel :
Information Theory Workshop (ITW), 2012 IEEE
Conference_Location :
Lausanne
Print_ISBN :
978-1-4673-0224-1
Electronic_ISBN :
978-1-4673-0222-7
DOI :
10.1109/ITW.2012.6404742
