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A study of three-dimensional optical code-division multiple-access for optical fiber sensor networks

COMPUTERS & ELECTRICAL ENGINEERING 2016年 49卷 136-145页

作者： Yen, Chih-Ta Chen, Chih-Ming Natl Formosa Univ Dept Elect Engn Multiuser Opt Commun Wireless Commun Syst Image P Yunlin Taiwan Natl Cheng Kung Univ Inst Comp & Commun Engn Tainan 701 Taiwan

This study proposes a novel optical fiber sensor (OFS) network using three-dimensional (3-D) wavelength/time/spatial optical code-division multiple-access (OCDMA) scheme. The proposed 3-D modified quadratic congruence/M-matrix (MQC/M-matrix) coding scheme overcome the restriction of single pulse per row inherent in traditional three-dimensional codes and maintain a high signal-to-noise ratio even when source power is low. The 3-D system is implemented using optical switches (OSW), fiber-Bragg gratings (FBGs), optical splitter and optical combiner. The noises of phase-induced intensity noise (PUN) and multiple access interference (MAI) in the decoding mechanism can be suppressed by using a spectral spreading scheme and balance-detection in the receivers. By constructing 3-D codes using bipolar pseudorandom (PN) codes rather than unipolar codes provides a significant increase in the maximum permissible number of active sensor nodes. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： optical fiber sensors (OFSs) Three-dimensional (3-D) optical code-division multiple-access (OCDMA) Fiber-Bragg grating (FBG) Phase-induced intensity noise (PIIN) multiple access interference (MAI)

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Tailoring chirped Moire fiber Bragg gratings for wavelength-division-multiplexing and optical code-division multiple-access applications

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FIBER AND INTEGRATED OPTICS 2000年第4期19卷 423-437页

作者： Chen, LR Smith, PWE Univ Toronto Dept Elect & Comp Engn Toronto ON Canada Photon Res Ontario Toronto ON Canada

The design and fabrication of chirped Moire fiber Bragg gratings (CMGs) are presented, which can be used in either (1) transmission as passband filters for providing wavelength selectivity in wavelength-division-multiplexed (WDM) systems or (2) reflection as encoding/decoding elements to decompose short broadband pulses in both wavelength and time in order to implement an optical code-division multiple-access (OCDMA) system. In transmission, the fabricated CMGs have single or multiple flattened passbands (<0.5 dB ripple) and exhibit >12 dB isolation and near constant in-band group delay. It is shown that these filters do not produce any measurable dispersion-induced power penalties when used to provide wavelength selectivity in 2.5 Gbit/s systems. It is also demonstrated how CMGs can be used in reflection to encode/decode short pulses from a wavelength-tunable mode-locked Er-doped fiber laser.

关键词： fiber Bragg gratings optical bandpass filters wavelength-division-multiplexing optical code-division multiple-access optical communications

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Multi-channel optical code-division multiple-access scheme based on super-structure fiber Bragg gratings

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OPTIK 2013年第15期124卷 2045-2049页

作者： Wen, Kun-Hua Yan, Lian-Shan Pan, Wei Luo, Bin Zou, Xi-Hua Zhu, Hong-Na Southwest Jiaotong Univ Sch Informat Sci & Technol Ctr Informat Photon & Commun Chengdu 610031 Sichuan Peoples R China

We propose a novel simultaneous multi-user en/decoder using super-structure fiber Bragg gratings (SFBGs) for multi-channel optical code-division multiple-access (OCDMA) applications. Each channel can generate and recognize codes for users individually. Therefore, the SFBG can make full use of the wavelength resource to enlarge the system capacity. In this paper, a 2-channel, 4-channel and 8-channel en/decoders are designed in a single SFBG with optimized performance for their auto-correlation peak over the maximum wing level ratios and peak over the maximum cross-correlation level ratios being larger than 17 and 10.2 dB, respectively. (C) 2012 Elsevier GmbH. All rights reserved.

关键词： Fiber Bragg grating optical code-division multiple-access Wavelength-division multiplexing

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Frequency-shift keying optical code-division multiple-access system with novel interference cancellation

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MICROWAVE AND optical TECHNOLOGY LETTERS 2008年第4期50卷 883-885页

作者： Karbassian, M. M. Ghafouri-Shiraz, H. Univ Birmingham Dept Elect Elect & Comp Engn Birmingham B15 2TT W Midlands England

A novel multiple user interference (MUI) cancellation technique is introduced with a reference signal which is data-free from the intended signal. It also simplifies the receiver architecture in synchronous M-ary wavelength or frequency shift keying (FSK) OCDMA. In the analysis, the system upper-bounded bit-error rate (BER) is derived taking into account the Poisson effect on the I/O characteristics of the photo-detectors (PD). It is found that the capacity of this system also increases by employing the proposed MUI canceller. In contrast to wavelength-division multiplexing (WDM), fewer wavelengths are needed as a result of M-ary source coding. (c) 2008 Wiley Periodicals, Inc.

关键词： M-ary frequency-shift keying multi-user interference optical code-division multiple-access prime code families

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2(n) coding architecture for optical code-division multiple-access

2(n) coding architecture for optical code-division multiple-...

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Conference on All-optical Communication Systems - Architecture, Control, and Network Issues II

作者： Kwong, WC Yang, GC Prucnal, PR HOFSTRA UNIV DEPT ENGNHEMPSTEADNY 11550

ISBN: (纸本)0819423211

Recent study shows that optical code-division multiple-access (CDMA) networks cannot be evaluated or designed by only considering the performance (i.e., correlation properties) of the optical pseudo-orthogonal codes selected. The structures of optical encoders and decoders are another important factors to consider and are needed to coordinate with the selected optical codes as much as possible. As a result, a "serial" coding architecture for optical CDMA has been introduced. This new architecture is found particularly attractive for ultrafast optical processing and waveguide implementation for the future high-capacity, low-loss, all-optical CDMA networks. Since the optical encoder is made of a serial combination of 2×2 optical switches with n of them being biased to a "mix-split" state, the generated OOC's, so-called 2ⁿ codes, pose with a symmetric delay-distribution property. In this paper, we first experimentally demonstrate the serial coding architecture. Afterwards, some techniques for algebraically constructing 2ⁿ codes of weight 4 are presented.

关键词： serial coding architecture optical code-division multiple-access optical orthogonal codes

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Measurements of stimulated-Raman-scattering-induced tilt in spectral-amplitude-coding optical code-division multiple-access systems

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optical ENGINEERING 2009年第1期48卷 015001-1-015001-6页

作者： Al-Qazwini, Zaineb A. T. Abdullah, Mohamad K. Mokhtar, Makhfudzah B. Natl Univ Singapore Dept Elect & Comp Engn Singapore 117576 Singapore Significant Technol Sdn Bhd Sri Kembangan 43300 Selangor Malaysia Univ Putra Malaysia Dept Comp & Commun Syst Engn Fac Engn Upm Serdang 43400 Selangor Malaysia

We measure the stimulated Raman scattering (SRS)-induced tilt in spectral-amplitude-coding optical code-division multiple-access (SAC-OCDMA) systems as a function of system main parameters (transmission distance, power per chip, and number of users) via computer simulations. The results show that SRS-induced tilt significantly increases as transmission distance, power per chip, or number of users grows. (C) 2009 Society of Photo-optical Instrumentation Engineers. [DOI: 10.1117/1.3063113]

关键词： stimulated Raman scattering stimulated Raman scattering tilt optical code-division multiple-access optical nonlinearities

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Performance analysis of new optical matrices for constructing two-dimensional temporal/spatial optical code-division multiple-access networks

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optical ENGINEERING 2017年第4期56卷 040501-040501页

作者： Lee, Chia-Yen Chang, Yao-Tang Tseng, Shin-Pin Lu, Yi-Xuan Natl United Univ Dept Elect Engn Miaoli Taiwan Kao Yuan Univ Dept Informat Technol Kaohsiung Taiwan

This study presents designs for developing two-dimensional optical matrices exhibiting low cross correlation and excellent orthogonality. The key scheme is to use original one-dimensional temporal codes and a particular mapping technique. A two-dimensional temporal/ spatial optical code-division multiple-access network using the proposed optical matrices was also constructed. This study subsequently analyzed the effect of multiuser interference on code performance. The analysis result reveals that some families of optical codes applied to the network theoretically provided a favorable code performance level. (C) 2017 Society of Photo-optical Instrumentation Engineers (SPIE)

关键词： low cross correlation optical code-division multiple-access optical orthogonal code optical orthogonal matrix

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Polarization diversity scheme on spectral polarization coding optical code-division multiple-access network

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optical ENGINEERING 2010年第12期49卷 125005-125005页

作者： Yen, Chih-Ta Huang, Jen-Fa Chang, Yao-Tang Chen, Bo-Hau Natl Formosa Univ Dept Elect Engn Yunlin Taiwan Natl Cheng Kung Univ Dept Elect Engn Tianan City 701 Taiwan Kao Yuan Univ Dept Electroopt Sci & Engn Lujhu Township 821 Kaohsiung Cty Taiwan

We present an experiment demonstrating the spectral-polarization coding optical code-division multiple-access system introduced with a nonideal state of polarization (SOP) matching conditions. In the proposed system, the encoding and double balanced-detection processes are implemented using a polarization-diversity scheme. Because of the quasiorthogonality of Hadamard codes combining with array waveguide grating routers and a polarization beam splitter, the proposed codec pair can encode-decode multiple code words of Hadamard code while retaining the ability for multiple-access interference cancellation. The experimental results demonstrate that when the system is maintained with an orthogonal SOP for each user, an effective reduction in the phase-induced intensity noise is obtained. The analytical SNR values are found to overstate the experimental results by around 2 dB when the received effective power is large. This is mainly limited by insertion losses of components and a nonflattened optical light source. Furthermore, the matching conditions can be improved by decreasing nonideal influences. (c) 2010 Society of Photo-optical Instrumentation Engineers. [DOI: 10.1117/1.3526335]

关键词： spectral-polarization coding optical code-division multiple-access state of polarization multiple-access interference phase-induced intensity noise

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Reducing BER of spectral-amplitude coding optical code-division multiple-access systems by single photodiode detection technique

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JOURNAL OF THE EUROPEAN optical SOCIETY-RAPID PUBLICATIONS 2013年 8卷

作者： Al-Khafaji, H. M. R. Aljunid, S. A. Amphawan, A. Fadhil, H. A. Safar, A. M. Univ Malaysia Perlis Sch Comp & Commun Engn Perlis Malaysia Univ Utara Malaysia Sch Comp Internetworks Res Grp Kedah Malaysia

In this paper, we present a single photodiode detection (SPD) technique for spectral-amplitude coding optical code-division multiple-access (SAC-OCDMA) systems. The proposed technique eliminates both phase-induced intensity noise (PIIN) and multiple-access interference (MAI) in the optical domain. Analytical results show that for 35 simultaneous users transmitting at data rate of 622 Mbps, the bit-error rate (BER) = 1.4 x 10(-28) for SPD technique is much better compared to 9.3 x 10(-6) and 9.6 x 10(-3) for the modified-AND(n) as well as the AND(a) detection techniques, respectively. Moreover, we verified the improved performance afforded by the proposed technique using data transmission simulations. [DOI: http://***/10.2971/jeos.2013.13022]

关键词： optical code-division multiple-access spectral-amplitude coding single photodiode detection technique multiple-access interference phase-induced intensity noise

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Investigation of in-band transmission of both spectral amplitude coding/optical code division multiple-access and wavelength division multiplexing signals

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optical ENGINEERING 2011年第6期50卷 065001-065001页

作者： Ashour, Isaac A. M. Shaari, Sahbudin Shalaby, Hossam M. H. Menon, P. Susthitha Univ Kebangsaan Malaysia Inst Microengn & Nanoelect Ukm Bangi 43600 Selangor Malaysia Egypt Japan Univ Sci & Technol Dept Elect & Commun Engn Sch Elect Commun & Comp Engn Alexandria 21934 Egypt

The transmission of both optical code division multiple-access (OCDMA) and wavelength division multiplexing (WDM) users on the same band is investigated. code pulses of spectral amplitude coding (SAC)/optical code division multiple-access (CDMA) are overlaid onto a multichannel WDM system. Notch filters are utilized in order to suppress the WDM interference signals for detection of optical broadband CDMA signals. Modified quadratic congruence (MQC) codes are used as the signature codes for the SAC/OCDMA system. The proposed system is simulated and its performance in terms of both the bit-error rate and Q-factor are determined. In addition, eavesdropper probability of error-free code detection is evaluated. Our results are compared to traditional nonhybrid systems. It is concluded that the proposed hybrid scheme still achieves acceptable performance. In addition, it provides enhanced data confidentiality as compared to the scheme with SAC/OCDMA only. It is also shown that the performance of the proposed system is limited by the interference of the WDM signals. Furthermore, the simulation illustrates the tradeoff between the performance and confidentiality for authorized users. (C) 2011 Society of Photo-optical Instrumentation Engineers (SPIE). [DOI:10.1117/1.3589296]

关键词： optical network security spectral amplitude coding optical code-division multiple-access wavelength division multiplexing modified quadratic congruence

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