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This paper presents the numerical analysis of 2Dimensional (2-D) FCC-MDW of the Optical Code Division Multiple Access (OCDMA) based on variations of transmission bit rate. This 2-D OCDMA code is a combination of 1-D Flexible Cross Correlation (FCC) and 1-D Modified Double Weight (MDW). The performance of 2-D FCC-MDW is evaluated at different bit rate; 622Mbps, 1Gbs and 2.5Gbps and can be demonstrated...
Many FSO communication systems are using a conventional technique that is OOK technique in the system. Some enhancement of technique is explained in this paper to decrease the error rate that occurs in the system. The comparison between OOK technique and DDM technique is investigated in order to compare the error rate and power received. The result shows that the performance of DDM technique generates...
This paper develops new coding technique to generate multiplexed patterns for Duty-Cycle Division Multiplexing (DCDM) which allows users to share the single transmission medium by assigning different duty cycles for each user. This coding technique aims to reduce the amount of noise which is added due to multilevel signalling. Single channel back-to-back optical fibre system is designed based on the...
This paper organizes the performance of twodimensional (2-D) Modified Double Weight (MDW) code for Optical Code Division Multiple Access (OCDMA) system by employing Avalanche Photodiodes (APD) as a gain. To accomplish the perfection system capacity, their cardinality, bit error rates (BER) and noise interferences are analyzed. With 2-D MDW with APD able to recovered the cardinality at least 61%, which...
Free Space Optical communication system is a technology that solves the problem of network connectivity. In this system, it contains a coding and technique to control the data that transferred using a laser beam from transmitter station through the atmosphere to receiver station. This technique is to optimize the error rate and improve the signal received. In this paper, the comparison between conventional...
This paper investigates the performance of hybrid scheme of subcarrier multiplexed spectral-amplitude-coding optical code division multiple access (SCM SAC-OCDMA) system based on AND Subtraction detection. In this system, Recursive Combinatorial (RC) code is used where it is a new code structure in SAC-OCDMA. The effects of noise such as phase-induced intensity (PIIN) noise, thermal noise and intermodulation...
Research in optical communications is always determined by fundamentals for high information rates and enhanced spectral efficiency. Also, the development of highrequest modulation formats is included a higher bit rates per channel, which requirement expanded signal-to-noise ratio considerably and high power per channel. Then again, higher spectral efficiency also needs closely spaced channels to...
In this paper, an indoor optical wireless CDMA system based on zero cross correlation (ZCC) code is investigated under the influence of ambient light noise. We consider line of sight communication links between multiple emitters and receivers. We first establish an analytical expression of bit error rate and then validate its estimations with the simulated results. The finding results show a great...
This paper analyses the spectral efficiency of hybrid subcarrier multiplexed (SCM) Optical Code Division Multiple Access (OCDMA) and conventional OCDMA based on AND Subtraction technique. We compared the spectral efficiency of SCM and the conventional OCDMA with respect the number of weights and number of users. Results indicate that the SCM OCDMA is more efficient compared to conventional OCDMA.
This paper presents the carried out investigation on nonlinear effects in semiconductor optical amplifier (SOA); in particular two-photon absorption process and its induced free carriers. The simulation results show nonlinear phase shift and the spectral broadening is induced by nonlinear free-carrier effect after propagation through the SOA. The levels of injected carrier density in SOA are varied...
This research work focuses to design Hybrid OCDMA over WDM system with advance modulation techniques DPSK which will improve the performance for long distance fiber length. Hybrid system merges with different types of techniques like OCDMA and WDM. Modified double weight (MDW) code is proposed as the signature address code. Multiuser interference and increase the bit-error-rate might be condense satisfactory...
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