Paper Info
Title
Information Theoretic Limits of Improved ACO-OFDM Receivers
Abstract
We consider performance enhancement of asymmetrically clipped optical orthogonal frequency division multiplexing (ACO-OFDM), which is a variation of OFDM in intensity modulated optical wireless communications. To improve the conventional ACO-OFDM receiver that utilizes only odd-indexed subcarriers, several specific designs have been proposed in the literature. Unlike these studies, this paper investigates information theoretic limits of all possible improved receivers. More specifically, we prove that the maximum achievable information rate of ACO-OFDM is the sum of (i) the information rate of the conventional receiver, and (ii) a single-letter conditional mutual information expression corresponding to the maximum achievable gain of improved receivers. Asymptotic analysis shows that the high-signal-to-noise-ratio (high-SNR) limit of the maximum achievable gain of arbitrary improved receivers is 3 dB in (electrical) SNR, corresponding to an information rate gain of exactly 1/4 bits per channel use. We also show that the low-SNR limit of the maximum achievable gain of improved receivers is approximately 1.35 dB in SNR. Numerical evaluation of finite-SNR gains demonstrate that improved ACO-OFDM receivers may reduce the gap to capacity significantly, especially at lowto-moderate SNR.
Year
DOI
Venue
2021
10.1109/VTC2021-FALL52928.2021.9625572
2021 IEEE 94TH VEHICULAR TECHNOLOGY CONFERENCE (VTC2021-FALL)
DocType
ISSN
Citations 
Conference
2577-2465
0
PageRank 
References 
Authors
0.34
0
4
Name
Order
Citations
PageRank
Xiaozhen Liu100.34
Jing Zhou200.34
Nuo Huang300.34
Wenyi Zhang470562.34