Quantum key distribution is a new method in key distribution system in cryptography used to transmit secret key between two legitimate parties. This method is an invention in quantum cryptography as part of quantum me...
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Quantum key distribution is a new method in key distribution system in cryptography used to transmit secret key between two legitimate parties. This method is an invention in quantum cryptography as part of quantum mechanics which solves the key distribution's problem in cryptosystem by providing a secure communication channel between two parties with absolute security guaranteed by the laws of physics. communication not only occurred in wired medium but also in wireless medium. WLAN as a wireless medium are much noisier and less reliable in general than wired mediums. This type of noise will generate different numbers of key length and also different level of error rate estimation. Thus, how much secure of the data could be protected on wireless communication? In this study, we implement BB84 protocol on 802.11i wireless local area network (WLAN) to show the affect of noise and eavesdropper could make the data transmission is much secure in wireless medium. In our study shows that implementation of BB84 in 802.11i is able to secure the key distribution from being stealing by the third party.
By employing 2D plane wave expansion (PWE) and finite difference time domain (FDTD) methods,a photonic crystal waveguide (PCW) based on the compound square lattice structure is presented. Band-gap can be observed for ...
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By employing 2D plane wave expansion (PWE) and finite difference time domain (FDTD) methods,a photonic crystal waveguide (PCW) based on the compound square lattice structure is presented. Band-gap can be observed for TM polarization and compared with the simple lattice structure based on the same material,the band-gap is increased by 62.7%. Byoptimizing the parameters we get the PCW with the propagation only near the wavelength of 1.55 μm and a flat group indexcurve in a wide wavelength range of 40 nm. And the group velocity dispersion compensation can be realized by thestructure optimization. The results provide a reference for the study and application of photonic crystal waveguide based on the compound lattice structure.
A new generation algorithm of two-dimensional triple-codeweight asymmetric optical orthogonal codes for optical code division multiple access （OCDMA） networks is proposed. The code cardinality is obtained and the er...
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A new generation algorithm of two-dimensional triple-codeweight asymmetric optical orthogonal codes for optical code division multiple access （OCDMA） networks is proposed. The code cardinality is obtained and the error-probability performance for corresponding OCDMA system is analyzed. The codes with two constraints （i.e., auto- and cross-correlation properties） being unequal are taken into account. On the premise of fixed system resources, the code of the error-probability performance, it is shown cardinality can be significantly improved. By analysis that the codes with different parameters have different performances. Therefore, this type of codes can be applied to support diverse quality of service （QoS） and satisfy the quality requirement of different multimedia or distinct users, and simultaneously make the better use of bandwidth resources in oDtical networks.
We numerically investigate four-wave-mixing （FWM） based multichannel wavelength conversion for amplitude-modulated signals, phase-modulated signals, together with mixed amplitude and phase modulated signals. This pa...
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We numerically investigate four-wave-mixing （FWM） based multichannel wavelength conversion for amplitude-modulated signals, phase-modulated signals, together with mixed amplitude and phase modulated signals. This paper also discusses the influence of stimulated Brillouin scattering （SBS） effects on high-efficiency FWM-based wavelength conversion applications. Our simulation results show that DPSK signals are more suitable for FWM-based multichannel wavelength conversion because the OOK signals will suffer from the inevitable data- pattern-dependent pump depletion. In future applications, when the modulation format is partially upgraded from OOK to DPSK, the influence of OOK signals on the updated DPSK signals must be considered when using multi-channel wavelength conversion. This influence becomes severe with the increase of OOK channel number. It can be concluded that DPSK signals are more appropriate for both transmission and multichannel wavelength conversion, especially in long haul and high bit-rate system.
We numerically investigate the main constrains for high efficiency wavelength conversion of differential phase-shift keying （DPSK） signals based on four-wave mixing （FWM） in highly nonlinear fiber （HNLF）. Using ...
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We numerically investigate the main constrains for high efficiency wavelength conversion of differential phase-shift keying （DPSK） signals based on four-wave mixing （FWM） in highly nonlinear fiber （HNLF）. Using multi-tone pump phase modulation techniques, high efficiency wavelength conversion of DPSK signals is achieved with the stimulated BriIlouin scattering （SBS） effects effectively suppressed. Our analysis shows that there is a compromise between conversion efficiency and converted idler degradation. By optimizing the pump phase modulation configuration, the converted DPSK idler＇s degradation can be dramatically decreased through balancing SBS suppression and pump phase modulation degradation. Our simulation results also show that these multi-tone pump phase modulation techniques are more appropriate for the future high bit rate systems.
A slotted single-mode photonic crystal waveguide with a linear tapered slot is presented to realize slow light,whose dispersion curve is shifted by changing the slot *** the slot width is reduced,the band curve shifts...
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A slotted single-mode photonic crystal waveguide with a linear tapered slot is presented to realize slow light,whose dispersion curve is shifted by changing the slot *** the slot width is reduced,the band curve shifts in the tapered structure,and the group velocity of light approach zero at the cut-off ***,different frequency components of the guided light are slowed down even localized along the propagation direction inside a tapered slot photonic crystal ***,this structure can confine slow light-wave in a narrow slot waveguide,which may effectively enhance the interaction between slow light and the low-index wave-guiding materials filled in the *** addition,this tapered slot structure can be used to compensate group velocity dispersion of slow light by modifying the structure,thus opening the opportunity for ultra-wide bandwidth slow light.
The wide field-of-view(FOV) optical receiver has many advantages in optical wireless communication,sensing and ***,the FOV is limited by some tradeoffs of the receiver's components employing conventional optical *...
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The wide field-of-view(FOV) optical receiver has many advantages in optical wireless communication,sensing and ***,the FOV is limited by some tradeoffs of the receiver's components employing conventional optical ***,present mechanisms to extend the FOV are not *** realize the wide FOV receiver effectively,we propose surface plasmon polaritons(SPPs) as the potential *** examples are presented to lively illustrate SPPs' striking power to offer unexpected solutions to conventional *** is shown that unusual conditions should be explored to make use of SPPs under some *** of localized SPPs,which are independent of the incidence angle,are suggested as the mechanism for the wide FOV *** progress in the optimization of SPPs' excitation at oblique incidence is also reported.
A two-dimensional （2D） optimized nanotaper mode converter is presented and analyzed using the finite- difference time-domain （FDTD） method. It can convert the mode size in a silicon pillar waveguide （PWG） from 4...
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A two-dimensional （2D） optimized nanotaper mode converter is presented and analyzed using the finite- difference time-domain （FDTD） method. It can convert the mode size in a silicon pillar waveguide （PWG） from 4 μm to 1 μm over a length of 7 μm and achieve a transmission efficiency of 83.6% at a wavelength of 1.55 μm. The dual directional mode conversion of the nanotaper and its ability to perform mode compression and expansion are also demonstrated. The broadband with high transmittance is satisfied in this structure. Using this silicon-based nanotaper, mode conversion between integrated photonic devices can be more compact and efficient.
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