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Wide-Band Optical Frequency Hopping Using Digital Chaos
Journal of Signal Processing Systems, 2019A wide-band optical frequency hopping (FH) scheme is proposed and analyzed using hyper digital chaos, where the chaotic sequences are applied to encrypt the original data in physical layer during transmission. The multi-fold data encryption is achieved based on the dynamic generation of the optical carrier frequency, FH rate as well as the available ...
Cong Geng, Xuelin Yang, Weisheng Hu
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Brillouin frequency shift hopping in polymer optical fiber
Applied Physics Letters, 2014We investigated the Brillouin gain spectrum dependence on large strain of up to 60% in a polymer optical fiber (POF) at 1.55 μm, and found that the Brillouin frequency shift (BFS) abruptly changes from ∼2.7 GHz to ∼3.2 GHz. We named this phenomenon “BFS hopping,” and found it to originate from the varied acoustic velocity induced by the stepwise change
Neisei Hayashi +3 more
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Demonstration of an optical frequency-hopping scheme for secure communications
2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, 2006We proposed and demonstrated the optical frequency-hopping system for long distance secure communications. 10.6-Gb/s error-free transmission through 20-km DSF and 40-km SMF was implemented in a 2-frequency-hopping system.
null Li Huo +4 more
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Frequency-hopping optical orthogonal codes with arbitrary time-blank patterns
Applied Optics, 2002We investigate a general scheme of frequency-hopping optical orthogonal codes with a specified distance between adjacent frequency symbols and propose a novel code that allows time blanks between adjacent frequency symbols in code sequences. A time blank represents the absence of frequency symbols in code sequences and makes no interference with ...
Jinsoo, Kim +3 more
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Asia Communications and Photonics Conference/International Conference on Information Photonics and Optical Communications 2020 (ACP/IPOC), 2020
In this paper, a hybrid optical frequency hopping system based on OAM multiplexing is proposed, which is mainly applied to the security of free space optical communication. In the proposed scheme, the segmented users’ data goes through two stages of hopping successively to realize data hiding. And the security performance is also analyzed in this paper.
Ya Jin +6 more
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In this paper, a hybrid optical frequency hopping system based on OAM multiplexing is proposed, which is mainly applied to the security of free space optical communication. In the proposed scheme, the segmented users’ data goes through two stages of hopping successively to realize data hiding. And the security performance is also analyzed in this paper.
Ya Jin +6 more
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Multirate optical fast frequency hopping CDMA system using power control
Globecom '00 - IEEE. Global Telecommunications Conference. Conference Record (Cat. No.00CH37137), 2002We propose a new multirate optical communication system using optical fast frequency hopping CDMA (OFFH-CDMA) for multimedia applications in which different quality of services (QoS) are required. In this system, each user needs only to transmit the minimum required power to achieve a desired signal to interference ratio (SIR).
Elie Inaty +2 more
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Evaluation of soft decoding for optical frequency-hopping channels with beat noise
GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489), 2004In this paper the performance of optical fast frequency-hopping with forward error correction is evaluated. Beat noise is the main performance limitation for a low-complexity implementation using optical filtering of incoherent light. Taking the beat noise into account, we show how to improve the performance with channel coding and soft decoding ...
Henrik Lundqvist, Gunnar Karlsson
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Passive optical fast frequency-hop CDMA communications system
Journal of Lightwave Technology, 1999This paper proposes an all-fiber fast optical frequency-hop code division multiple access (FFH-CDMA) for high-bandwidth communications. The system does not require an optical frequency synthesizer allowing high communication bit rates. Encoding and decoding are passively achieved by Bragg gratings, Multiple Bragg gratings replace a frequency ...
H. Fathallah, L.A. Rusch, S. LaRochelle
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New architecture and codes for optical frequency-hopping multiple access
SPIE Proceedings, 1998We propose a new architecture for an optical fast frequency- hop code division multiple access system using tunable Bragg gratings. Previously proposed architectures called for a series of in-fiber Bragg gratings, each independently tunable with a piezo-electric device.
Louis-Patri Boulianne, Leslie A. Rusch
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Frequency-hopped spread spectrum optical processor
Annual Meeting Optical Society of America, 1987A real-time optical processor that can detect spread spectrum signals transmitted by the frequency-hopping method is presented. The system can generate the 2-D correlation distribution between the reference data and the input data at the output plane of the optical processor.
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