TY - JOUR
T1 - Adaptive Acquisition Schemes for Photon-Limited Free-Space Optical Communications
AU - Bashir, Muhammad Salman
AU - Alouini, Mohamed Slim
N1 - Funding Information:
Manuscript received January 14, 2020; revised May 25, 2020 and July 29, 2020; accepted September 2, 2020. Date of publication September 30, 2020; date of current version January 15, 2021. This work is supported by the Office of Sponsored Research (OSR) at King Abdullah University of Science and Technology (KAUST). The associate editor coordinating the review of this article and approving it for publication was W. Xu. (Corresponding author: Muhammad Salman Bashir.) The authors are with the Computer, Electrical and Mathematical Science and Engineering (CEMSE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia (e-mail: [email protected]; [email protected]).
Publisher Copyright:
© 1972-2012 IEEE.
PY - 2021/1/1
Y1 - 2021/1/1
N2 - Acquisition and tracking systems form an important component of free-space optical communications due to directional nature of the optical signal. Acquisition subsystems are needed in order to search and locate the receiver terminal in an uncertainty/search region with very narrow laser beams. In this paper, we have proposed and analyzed two adaptive search schemes for acquisition systems that perform better-for the low probability of detection-than the spiral scanning approach. The first of these schemes, the adaptive spiral search, provides a better acquisition time performance by dividing the search region into a number of smaller subregions, and prioritizing search in regions of higher probability mass. The second technique-The shotgun approach-searches the region in a random manner by sampling the search region according to a Gaussian distribution. The adaptive spiral scheme outperforms the shotgun approach in terms of acquisition time, especially if the number of search subregions is large enough. However, a higher pointing accuracy is required by the adaptive spiral search in order to search the region precisely. On the other hand, the shotgun scanning approach does not require such stringent pointing accuracy.
AB - Acquisition and tracking systems form an important component of free-space optical communications due to directional nature of the optical signal. Acquisition subsystems are needed in order to search and locate the receiver terminal in an uncertainty/search region with very narrow laser beams. In this paper, we have proposed and analyzed two adaptive search schemes for acquisition systems that perform better-for the low probability of detection-than the spiral scanning approach. The first of these schemes, the adaptive spiral search, provides a better acquisition time performance by dividing the search region into a number of smaller subregions, and prioritizing search in regions of higher probability mass. The second technique-The shotgun approach-searches the region in a random manner by sampling the search region according to a Gaussian distribution. The adaptive spiral scheme outperforms the shotgun approach in terms of acquisition time, especially if the number of search subregions is large enough. However, a higher pointing accuracy is required by the adaptive spiral search in order to search the region precisely. On the other hand, the shotgun scanning approach does not require such stringent pointing accuracy.
KW - acquisition
KW - acquisition time
KW - adaptive spiral search
KW - Free-space optical communications
KW - photon-counting detector
KW - photon-limited system
KW - probability of detection
KW - probability of false alarm
KW - shotgun approach
UR - http://www.scopus.com/inward/record.url?scp=85099763904&partnerID=8YFLogxK
U2 - 10.1109/TCOMM.2020.3027886
DO - 10.1109/TCOMM.2020.3027886
M3 - Article
AN - SCOPUS:85099763904
VL - 69
SP - 416
EP - 428
JO - IEEE Transactions on Communications
JF - IEEE Transactions on Communications
SN - 1558-0857
IS - 1
M1 - 9210018
ER -