Title :
Outage capacity with non-uniform signaling for free-space optical channels
Author :
Farid, Ahmed A. ; Hranilovic, Steve
Author_Institution :
Dept. of Electr. & Comput. Eng., McMaster Univ., Hamilton, ON
Abstract :
The outage capacity of slow-fading free-space optical (FSO) channels is derived with pulse amplitude modulation (PAM) signaling. Both uniform and non-uniform discrete input distributions are considered. For practical implementation, a non-uniform distribution with quantized-level probabilities is proposed. The combined effects of atmospheric turbulence, pointing errors and transmitter beamwidth are considered in the analysis. An upper and achievable lower bounds on the outage capacity are presented. For a given outage probability, a significant increase in the transmitted data rate, 5-10 times, is noticed when the non-uniform signaling scheme is employed over the widely used uniform 2-PAM signaling.
Keywords :
channel capacity; fading channels; optical communication; probability; telecommunication signalling; atmospheric turbulence; free-space optical channels; nonuniform discrete input distributions; nonuniform signaling; outage capacity; outage probability; pointing errors; quantized-level probabilities; slow-fading free-space optical channels; transmitter beamwidth; Atmospheric modeling; Capacity planning; Fading; Intensity modulation; Optical modulation; Optical receivers; Optical refraction; Optical transmitters; Optical variables control; Signal analysis;
Conference_Titel :
Communications, 2008 24th Biennial Symposium on
Conference_Location :
Kingston, ON
Print_ISBN :
978-1-4244-1945-6
Electronic_ISBN :
978-1-4244-1946-3
DOI :
10.1109/BSC.2008.4563239