Author
Dabiri, M. T., Khankalantary, S., Safi, H., Piran, Md.J., Ansari, I. S., Suh, D.Y., Uysal, Murat
Publication Date
2021-11-01
Publication Place
-
IEEE
Subject
Atmospheric turbulence, Blind data detection, Differential signaling, Free-space optics, Synchronization
Type
Periodical
Language
English
Digital
Yes
Manuscript
No
Library
Özyeğin University
Library Asset ID
0018-9545
Record ID
d9132bb3-6d14-4b8b-a4d0-fd69399669da
Library Location
Electrical & Electronics Engineering
Date
2021-11-01
Sample Text
In this paper, the problem of timing error for freespace optical links with high mobility is investigated. In particular, we consider a real scenario in which the sampling clock offset is randomly changing and, in addition, the receiver has no information about the instantaneous channel coefficient as well as instantaneous timing error. Moreover, we consider a general case with signal dependent noise. For the considered scenario, for a conventional receiverwith one sampler, we propose an iterative detectionmethod based on the expectation-maximization (EM) algorithm. In the presence of large values of sampling clock offset, shifted error is the dominant error. Hence, in order to reduce the impact of shifted error probability, we propose an iterative data detection method for a receiver which utilizes two shifted samplers. The proposed iterative detection method only requires a series of simple addition and multiplication operation and does not require to solve any integral equations. A set of simulation results are provided to study the system performance for the proposed detectionmethods. Simulation results demonstrate that for a receiver with two samplers, by using the proposedEM-based detector,we can achieve bit error rate performance very close to the ideal receiver that perfectly knows the instantaneous channel coefficient and sampling clock offset.
DOI
10.1109/TVT.2021.3113603
Cilt
70
