Results 141 to 150 of about 2,557 (191)
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Performance comparison of coherent time-spreading PPM-OCDMA and OOK-OCDMA systems
SPIE Proceedings, 2009We compared the bit-error-rate (BER) and throughput performance of coherent time-spreading (TS) optical code division multiple access (OCDMA) systems with PPM (pulse-position modulation) and OOK (on-off keying) signaling. The results indicate that PPM-OCDMA with an appropriate pulse position multiplicity performs better than OOK-OCDMA in the receivers'
Xiaogang Chen, Dexiu Huang
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2007 9th International Conference on Transparent Optical Networks, 2007
The optical code division multiple access (OCDMA) over wavelength division multiplexing (WDM) passive optical network (PON) system has been proposed as a potential candidate for gigabit-symmetric fiber-to-the- home (FTTH) services. Asynchronous OCDMA over WDM systems have been experimentally demonstrated using superstructured fiber Bragg gratings ...
X. WANG +5 more
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The optical code division multiple access (OCDMA) over wavelength division multiplexing (WDM) passive optical network (PON) system has been proposed as a potential candidate for gigabit-symmetric fiber-to-the- home (FTTH) services. Asynchronous OCDMA over WDM systems have been experimentally demonstrated using superstructured fiber Bragg gratings ...
X. WANG +5 more
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Improving OCDMA System via Combination of OFDM/OCDMA Techniques
Applied Mechanics and Materials, 2014This paper proposes a single sideband orthogonal frequency division multiplexing (SSB-OFDM) incorporated with spectral amplitude coding (SAC) optical code division multiple accesses (SAC-OCDMA). This scheme is a new technique designed to enhance overall OCDMA system performance.
A.O. Aldhaibani +3 more
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Optimal performance of an oversaturated OCDMA/OCDMA system based on scrambled orthogonal bases
The 13th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, 2003We consider a multiple access system with oversaturation of the channel by means of a combined OCDMA/OCDMA scheme with scrambled orthogonal bases. We investigate the performance and the associated maximum channel capacity (channel load) for uncoded BPSK modulation with binary valued chip sequences and optimum multiuser detection for spreading factor N =
Frederik Vanhaverbeke, Marc Moeneclaey
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Coherent OCDMA receivers with robust performance
2011 45th Annual Conference on Information Sciences and Systems, 2011Optical code division multiple access can achieve good spectral efficiency, a high degree of security, and soft degradation in many network applications. Robust performance in the presence of key impairments is achieved by careful selection of encoding sequences according to correlation properties and spread-time pulse shapes.
Yi Yang +3 more
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An Improved OCDMA/OCDMA Overloading Scheme for Cellular DS-CDMA
2008Overloading is a scheme to accommodate more users than the spreading factor N. This is a bandwidth efficient scheme to increase the number of users in a fixed bandwidth. One of the efficient schemes to overload a CDMA system is to use two sets of orthogonal signal waveforms (O/O).
Preetam Kumar, Saswat Chakrabarti
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2D OCDMA System for Service Differentiation
2007 15th International Conference on Digital Signal Processing, 2007The incoherent optical code division multiple access (OCDMA) is studied as a potential access technique for multimedia applications. In this paper, we propose to provide service differentiation with 2D codes based on optical orthogonal code (OOC) namely: Multi-Wavelength optical orthogonal code (MWOOC).
Mikaël Morelle +3 more
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Native Multicasting in a 2D-OCDMA PON
IEEE Communications Letters, 2008Optical CDMA is proposed to implement a PON that supports downstream native optical multicasting. Common wavelengths within provisioned 2D codes may uniquely represent a multicast group. We introduce a simple architecture enabling native 2D-OCDMA multicasting without resorting to code tunability.
Kerim Fouli +2 more
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Advanced modulation techniques in OCDMA system
2007 Asia Optical Fiber Communication and Optoelectronics Conference, 2007Advance modulation techniques such as differential phase-shift keying (DPSK), differential quaternary phase shift keying (DQPSK) and code-shift-keying (CSK) modulation with balanced detection has been proposed and demonstrated in high capacity asynchronous optical code division access (OCDMA) system using different encoding/decoding schemes to beat the
X. WANG +4 more
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2008 International Conference on Photonics in Switching, 2008
Wavelength division multiplexing/optical code division multiple access (WDM/OCDMA) systems have been demonstrated in field trials in downtown Tokyo area. Multiport and SSFBG encoder/decoders, and DPSK modulation are key enabling techniques.
X. Wang +5 more
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Wavelength division multiplexing/optical code division multiple access (WDM/OCDMA) systems have been demonstrated in field trials in downtown Tokyo area. Multiport and SSFBG encoder/decoders, and DPSK modulation are key enabling techniques.
X. Wang +5 more
openaire +1 more source