Dr Arshad Chowdhury - Academia.edu (original) (raw)
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Papers by Dr Arshad Chowdhury
2012 IEEE 3rd International Conference on Photonics, 2012
Abstract We propose and demonstrate a low complexity non decision directed blind carrier recovery... more Abstract We propose and demonstrate a low complexity non decision directed blind carrier recovery algorithm (NDD-CRA) for 16-QAM optical coherent receivers. Through optimization of step size parameter (μ), we obtained similar performance compared to decision-directed phase estimation algorithm, however, our propose scheme has less complexity compared to the decision directed carrier recovery algorithm (DD-CRA) as the proposed scheme does not require any decision feedback module. From simulation, it is observed that the ...
2012 7th International Conference on Electrical and Computer Engineering, 2012
ABSTRACT We propose and demonstrate a new 112 Gbps Polarization division Multiplexing digital opt... more ABSTRACT We propose and demonstrate a new 112 Gbps Polarization division Multiplexing digital optical coherent systems with hexagonal 16-QAM (HEX-16-QAM) modulation. In our proposed system we use decision directed dispersion compensation algorithm which is Least Mean Square (LMS) algorithm and single tap decision directed carrier recovery algorithm. We compare the HEX-16-QAM systems with 16-QAM system for uncompensated transmission. Our analysis result found that HEX-16-QAM can achieve bit error rate (BER) of 1.5×10-4 whereas square 16-QAM BER is 5×10-4 for uncompensated 500-km transmission at 25 dB OSNR. Propose system achieve 0.3 dB OSNR penalty with compare to square 16-QAM system.
Journal of Organometallic Chemistry, 2014
Journal of Organometallic Chemistry, 2015
Journal of Organometallic Chemistry, 2014
The Journal of the Association of Physicians of India, Apr 1, 1993
Journal of Lightwave Technology, Oct 1, 2005
We report our recent research results in the area of optical label switching (OLS) for next-gener... more We report our recent research results in the area of optical label switching (OLS) for next-generation optical packet-switched networks. These include optical label generation, label swapping, optical time-delay buffering, clock recovery (CR), and wavelength conversion for optical packets.
16Th Opto Electronics and Communications Conference, 2011
Pramana J Phys, Dec 1, 2003
Absolute measurement for He-alpha resonance (1s^{2} ^{1}S_{0}-1s2p ^{1}P_{1}, at 40.2 Å) line emi... more Absolute measurement for He-alpha resonance (1s^{2} ^{1}S_{0}-1s2p ^{1}P_{1}, at 40.2 Å) line emission from a laser-produced carbon plasma has been studied as a function of laser intensity. The optimum laser intensity is found to be approx1.3 times 10^{12} W/cm^{2} for the maximum emission of 3.2 times 10^{13} photons sr^{-1} pulse^{-1}. Since this line lies in the water window spectral region, it has potential application in x-ray microscopic imaging of biological sample in wet condition. Theoretical calculation using corona model for the emission of this line is also carried out with appropriate ionization and radiative recombination rate coefficients.
2012 IEEE 3rd International Conference on Photonics, 2012
Abstract We propose and demonstrate a low complexity non decision directed blind carrier recovery... more Abstract We propose and demonstrate a low complexity non decision directed blind carrier recovery algorithm (NDD-CRA) for 16-QAM optical coherent receivers. Through optimization of step size parameter (μ), we obtained similar performance compared to decision-directed phase estimation algorithm, however, our propose scheme has less complexity compared to the decision directed carrier recovery algorithm (DD-CRA) as the proposed scheme does not require any decision feedback module. From simulation, it is observed that the ...
2012 7th International Conference on Electrical and Computer Engineering, 2012
ABSTRACT We propose and demonstrate a new 112 Gbps Polarization division Multiplexing digital opt... more ABSTRACT We propose and demonstrate a new 112 Gbps Polarization division Multiplexing digital optical coherent systems with hexagonal 16-QAM (HEX-16-QAM) modulation. In our proposed system we use decision directed dispersion compensation algorithm which is Least Mean Square (LMS) algorithm and single tap decision directed carrier recovery algorithm. We compare the HEX-16-QAM systems with 16-QAM system for uncompensated transmission. Our analysis result found that HEX-16-QAM can achieve bit error rate (BER) of 1.5×10-4 whereas square 16-QAM BER is 5×10-4 for uncompensated 500-km transmission at 25 dB OSNR. Propose system achieve 0.3 dB OSNR penalty with compare to square 16-QAM system.
Journal of Organometallic Chemistry, 2014
Journal of Organometallic Chemistry, 2015
Journal of Organometallic Chemistry, 2014
The Journal of the Association of Physicians of India, Apr 1, 1993
Journal of Lightwave Technology, Oct 1, 2005
We report our recent research results in the area of optical label switching (OLS) for next-gener... more We report our recent research results in the area of optical label switching (OLS) for next-generation optical packet-switched networks. These include optical label generation, label swapping, optical time-delay buffering, clock recovery (CR), and wavelength conversion for optical packets.
16Th Opto Electronics and Communications Conference, 2011
Pramana J Phys, Dec 1, 2003
Absolute measurement for He-alpha resonance (1s^{2} ^{1}S_{0}-1s2p ^{1}P_{1}, at 40.2 Å) line emi... more Absolute measurement for He-alpha resonance (1s^{2} ^{1}S_{0}-1s2p ^{1}P_{1}, at 40.2 Å) line emission from a laser-produced carbon plasma has been studied as a function of laser intensity. The optimum laser intensity is found to be approx1.3 times 10^{12} W/cm^{2} for the maximum emission of 3.2 times 10^{13} photons sr^{-1} pulse^{-1}. Since this line lies in the water window spectral region, it has potential application in x-ray microscopic imaging of biological sample in wet condition. Theoretical calculation using corona model for the emission of this line is also carried out with appropriate ionization and radiative recombination rate coefficients.