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Shahdol, India

Felicita Vimala J.,DIET | Thomas Joseph Prakash J.,Bharathidasan University
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2013

Single crystal of 2 mol% l-Proline doped Bis Thiourea Zinc Acetate (BTZA), a semi organic nonlinear optical material has been grown using slow evaporation technique. Good quality single crystal with dimension 11 × 7 × 3 mm3 was harvested after 30 days. The influence of amino acid l-Proline was studied for 1, 2 and 3 mol% l-Proline doped BTZA using Kurtz and Perry powder second harmonic generation test. This was compared with pure BTZA which confirms the enhancement of second harmonic generation property of l-Proline doped BTZA. Better enhancement was found in 2 mol% l-Proline doping. The grown crystal was characterized using single crystal X-ray diffraction, Fourier Transform Infra Red spectroscopy (FTIR) analysis, UV-Visible absorption and thermogravimetric analysis. © 2013 Elsevier B.V. All rights reserved. Source

Bhatia K.S.,Rayat Bahra Institute of Engineering and Nano Technology | Kaler R.S.,Thapar University | Kamal T.S.,DIET | Randhawa R.,Punjabi University
Journal of Optical Communications | Year: 2012

This paper forces on the monitoring and compensation of optical telecommunication channels by using Optical add drop multiplexers (OADM) in an Optical orthogonal frequency division multiplexing (OOFDM) system. An adaptive fiber nonlinearity precompensation (AFNP) scheme is also proposed to solve the fiber nonlinearity in coherent optical orthogonal frequency division multiplexed networks (CO-OFDM). Optical performance monitoring (OPM) at end-terminals is applied to channel identification in this paper. It is considered to be high efficiency and a cost efficient technique in low-dynamic system. Copyright © 2012 De Gruyter. Source

Bhatia K.S.,Rayat Bahra Institute of Engineering and Nano Technology | Kamal T.S.,DIET
Journal of Optical Communications | Year: 2012

In this paper, we demonstrated the transmission performance through simulation for Integrated Dense Wavelength DivisionMultiplexing and Optical-OFDM system with OADM including the fiber nonlinearity effect. The effects on transmitted channels, fiber link length, operating optical signal wavelength, optical transmitted signal power, optical signal bandwidth, transmission bit rate, optical received power and bit error rate at the receiving side are observed. Copyright © 2012 De Gruyter. Source

Singh U.,GNDP College | Kumar H.,Sant Longowal Institute of Engineering And Technology | Kamal T.S.,DIET
Progress In Electromagnetics Research M | Year: 2010

This paper presents a novel optimization technique biogeography based optimization (BBO) for antenna array synthesis. BBO is a relatively new evolutionary global optimization technique based on the science of biogeography. It is capable of solving linear and non-linear problems. In this paper, BBO algorithm is used to determine an optimum set of amplitudes of antenna elements that provide a radiation pattern with maximum side lobe level reduction and/or null placement in the specified directions. The results obtained show the effectiveness of the BBO algorithm, and they are better than previous published results. Source

Singh U.,Guru Nanak Institutions | Kamal T.S.,DIET
IET Microwaves, Antennas and Propagation | Year: 2011

Biogeography-based optimisation (BBO) is employed for the optimisation of non-uniform circular antenna arrays. In BBO, the problem solutions are represented as islands and the sharing of features between solutions corresponds to immigration and emigration between the islands. The scheme of BBO is employed to find out an optimal set of weights and antenna element separations to provide a radiation pattern with maximum side lobe level (SLL) reduction with the constraint of a fixed major lobe beam width. The capability of BBO is demonstrated by taking different sizes of antennas. The results show that the design of non-uniform circular antenna arrays using the BBO algorithm offers a SLL reduction better than that obtained using genetic algorithms, particle swarm optimisation and simulated annealing.© 2011 The Institution of Engineering and Technology. Source

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