Sujit Mandal | National Institute of Technology, Durgapur (original) (raw)
Uploads
Papers by Sujit Mandal
In this paper, a new technique is proposed to optimize the conflicting parameters like low value ... more In this paper, a new technique is proposed to optimize the conflicting parameters like low value of maximum side lobe level (SLL), narrow beam-width of the main beam and low value of maximum sideband radiation level (SRL) of time-modulated linear antenna arrays (TMLAAs). The method is based on minimizing a multi-objective fitness function by using single-objective differential evolution algorithm (DEA) technique. The method is applied to both uniformly excited TMLAA (UE-TMLAA) and non-uniformly excited TMLAA (NUE –TMLAA) to synthesize low side lobe optimum pattern at operating frequency by suppressing the sideband radiation level to a sufficiently low value. For UE-TMLAA only the switch-on time durations of the array elements and for NUE-TMLAA the switch-on time durations and the static amplitudes with predetermined dynamic range ratio (DRR) of static amplitudes are taken as the optimization parameters for the DEA. To show effectiveness of the proposed approach, the single-objective DEA optimized results are compared with those obtained by other single objective and multi-objective techniques that has been reported previously. Also, first null beam width (FNBW) and half power beam width (HPBW) of the DEA optimized patterns at fundamental radiation are compared with those of the Dolph-Chebyshev (D-C) pattern of same SLL.
Progress In Electromagnetics Research M, 2014
Engineering, 2012
Maximum charge per delay in a blasting round is universally accepted as the influencing parameter... more Maximum charge per delay in a blasting round is universally accepted as the influencing parameter to quantify magnitude of vibration for any distance of concern. However, for any blasting round experimental data reveals that for same charge per delay magnitude of vibration varies with total charge. Considering linear transmission of blast waves, the paper firstly investigates into the influence of explosive weight, blast design parameters and geology of strata on magnitude and characteristics of vibration parameters and thereafter communicates that possibly interference of blast waves generated from same and different holes of a blasting round result into variation in vibration magnitude. The paper lastly developed a mathematical model to evaluate points of interference of blast waves generated from single-and multi-hole blasting round.
2014 Fourth International Conference on Advances in Computing and Communications, 2014
In this paper, a novel optimization method based on single objective, that is, minimization of si... more In this paper, a novel optimization method based on single objective, that is, minimization of sideband radiation (SBR) of ultra-low side lobe, narrow beam patterns in time modulated antenna arrays (TMAAs) is proposed. The proposed method utilizes the weighting vectors of the low side lobe Dolph-Chebyshev/Taylor series patterns as the dynamic excitation coefficients of the desired pattern at fundamental radiation. Differential evolution algorithm is employed to distribute the static amplitudes and switch-on time durations in such a way that in the optimization process, dynamic excitation distribution remains the same. Static amplitudes are perturbed in a predefined search range of (0.25, 1), whereas the weighted values of switch-on time durations are obtained by dividing dynamic excitation coefficients by static amplitudes. The technique greatly simplifies the difficulties of multi-objective TMAA synthesizing problem by reducing it to a single-objective optimization problem. Numerical examples for a 32-element linear array are presented to produce ultra low side lobe Taylor n and Dolph-Chebyshev pattern with low value of maximum sideband radiation (SBR max ). The optimization results of the proposed method are also compared with those obtained by other optimization techniques, which have been reported previously.
In this paper, a new technique is proposed to optimize the conflicting parameters like low value ... more In this paper, a new technique is proposed to optimize the conflicting parameters like low value of maximum side lobe level (SLL), narrow beam-width of the main beam and low value of maximum sideband radiation level (SRL) of time-modulated linear antenna arrays (TMLAAs). The method is based on minimizing a multi-objective fitness function by using single-objective differential evolution algorithm (DEA) technique. The method is applied to both uniformly excited TMLAA (UE-TMLAA) and non-uniformly excited TMLAA (NUE –TMLAA) to synthesize low side lobe optimum pattern at operating frequency by suppressing the sideband radiation level to a sufficiently low value. For UE-TMLAA only the switch-on time durations of the array elements and for NUE-TMLAA the switch-on time durations and the static amplitudes with predetermined dynamic range ratio (DRR) of static amplitudes are taken as the optimization parameters for the DEA. To show effectiveness of the proposed approach, the single-objective DEA optimized results are compared with those obtained by other single objective and multi-objective techniques that has been reported previously. Also, first null beam width (FNBW) and half power beam width (HPBW) of the DEA optimized patterns at fundamental radiation are compared with those of the Dolph-Chebyshev (D-C) pattern of same SLL.
Progress In Electromagnetics Research M, 2014
Engineering, 2012
Maximum charge per delay in a blasting round is universally accepted as the influencing parameter... more Maximum charge per delay in a blasting round is universally accepted as the influencing parameter to quantify magnitude of vibration for any distance of concern. However, for any blasting round experimental data reveals that for same charge per delay magnitude of vibration varies with total charge. Considering linear transmission of blast waves, the paper firstly investigates into the influence of explosive weight, blast design parameters and geology of strata on magnitude and characteristics of vibration parameters and thereafter communicates that possibly interference of blast waves generated from same and different holes of a blasting round result into variation in vibration magnitude. The paper lastly developed a mathematical model to evaluate points of interference of blast waves generated from single-and multi-hole blasting round.
2014 Fourth International Conference on Advances in Computing and Communications, 2014
In this paper, a novel optimization method based on single objective, that is, minimization of si... more In this paper, a novel optimization method based on single objective, that is, minimization of sideband radiation (SBR) of ultra-low side lobe, narrow beam patterns in time modulated antenna arrays (TMAAs) is proposed. The proposed method utilizes the weighting vectors of the low side lobe Dolph-Chebyshev/Taylor series patterns as the dynamic excitation coefficients of the desired pattern at fundamental radiation. Differential evolution algorithm is employed to distribute the static amplitudes and switch-on time durations in such a way that in the optimization process, dynamic excitation distribution remains the same. Static amplitudes are perturbed in a predefined search range of (0.25, 1), whereas the weighted values of switch-on time durations are obtained by dividing dynamic excitation coefficients by static amplitudes. The technique greatly simplifies the difficulties of multi-objective TMAA synthesizing problem by reducing it to a single-objective optimization problem. Numerical examples for a 32-element linear array are presented to produce ultra low side lobe Taylor n and Dolph-Chebyshev pattern with low value of maximum sideband radiation (SBR max ). The optimization results of the proposed method are also compared with those obtained by other optimization techniques, which have been reported previously.