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Title: Channel-Prediction-Driven Rate Control for LDPC Coding in a Fading FSO Channel With Delayed Feedback
Free-space optical (FSO) links are sensitive to channel fading caused by atmospheric turbulence, varying weather conditions, and changes in the distance between the transmitter and receiver. To mitigate FSO fading, this paper applies linear and quadratic prediction to estimate fading channel conditions and dynamically select the appropriate low-density parity check (LDPC) code rate. This adaptivity achieves reliable communication while efficiently utilizing the available channel mutual information. Protograph-based Raptor-like (PBRL) LDPC codes supporting a wide range of rates are designed, facilitating convenient rate switching. When channel state information (CSI) is known without delay, dynamically selecting LDPC code rate appropriately maximizes throughput. This work explores how such prediction behaves as the feedback delay is increased from no delay to a delay of 4 ms for a channel with a coherence time of 10 ms.  more » « less
Award ID(s):
1955660
PAR ID:
10587906
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
IEEE
Date Published:
Journal Name:
IEEE Open Journal of the Communications Society
Volume:
6
ISSN:
2644-125X
Page Range / eLocation ID:
3320 to 3331
Subject(s) / Keyword(s):
Fading channels Optical feedback Predictive models Throughput Parity check codes Optical receivers Delays Coherence time Optical transmitters Optical sensors Channel state information free-space optical channel LDPC codes rate-adaptive coding
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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