A New Upper Bound for Free Space Optical Channel Capacity Using a Simple Mathematical in Equality
Subject Areas : Pervasive computing
Arezu
Rezazadeh
1
(Ferdowsi University of Mashhad)
Ghosheh
Abed Hodtani
2
( Ferdowsi University of Mashhad)
Keywords: Mathematical Inequality, Capacity, Upper Bound, Free Space Optical Channel, Optimal Input Distributions,
Abstract :
In this paper, by using a simple mathematical inequality, we derive a $ new upper bound fkr the capacity of$ free space optical channel in coherent case. Then, by applying general fading distribution, we obtain an upper bound for mutual information in non-coherent case. Finally, we derive the corresponding optimal input distributions for both coherent and non-coherent cases, compare the results with previous works numerically and illustrate that our results subsume some of previous results in special cases.