Jitha, B; Bybi, P C; Aanandan,C K; Mohanan, P(John Wiley & Sons, June , 2008)
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Abstract:
Design of a compact microstrip band reject filter is proposed. The device consists of an Open Loop Rectangular Resonator (OLRR) coupled to a microstrip line. The transmission line has a U-bend which enhances the coupling with the OLRR element and reduces the size of the filter. The filter can be made tunable by mounting variable capacitance to the system. Simulated and experimental results are presented.
Bindu, G; Vinu, Thomas; Anil, Lonappan; Aanandan,C K; Mathew, K T(John Wiley & Sons, January , 2006)
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Abstract:
A phantom that exhibits complex dielectric properties similar to low-water-content biological tissues over the electromagnetic spectrum of 2000–3000 MHz has been synthesized from carbon black, graphite powder, and poly vinyl acetate (PVA)-based adhesive. The material overcomes various problems that are inherent in conventional phantoms such as decomposition and deterioration due to the invasion of bacteria or mold. The absorption coefficients of the material for various concentrations of carbon and graphite are studied. A combination of 50% poly-vinyl-acetate-based adhesive, 20% carbon, and 30% graphite exhibits a high absorption coefficient, which suggests another application of the material as a good microwave absorber for the interior lining of tomographic chamber in microwave imaging. The cavity-perturbation technique is adopted to study the dielectric properties of the material.
Aanandan,C K; Mohanan, P; Supriyo,Dey; K G Nair(Department of Electronics, 1994)
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Abstract:
A simple technique to improve the impedance bandwidth of a circular
microstrip patch antenna using two sectorial slots is proposed. Using this
design more than 5% impedance bandwidth is obtained. The added
advantage of this new antenna is that it can be fed by a 50 microstrip
line.
Bindu, G; Santhosh John, Abraham; Anil, Lonappan; Vinu, Thomas; Aanandan,C K; Mathew, K T(International Journal of Cancer Research, 2006)
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Abstract:
Despite its recognized value in detecting and characterizing breast disease, X-ray
mammography has important limitations that motivate the quest for alternatives to augment
the diagnostic tools that are currently available to the radiologist. The rationale for pursuing
electromagnetic methods are based on the significant dielectric contrast between normal
and cancerous breast tissues, when exposed to microwaves. The present study analyzes
two-dimensional microwave tomographic imaging on normal and malignant breast tissue
samples extracted by mastectomy, to assess the suitability of the technique for early
detection ofbreast cancer. The tissue samples are immersed in matching coupling medium
and are illuminated by 3 GHz signal. 2-D tomographic images ofthe breast tissue samples
are reconstructed from the collected scattered data using distorted Born iterative method.
Variations of dielectric permittivity in breast samples are distinguishable from the obtained
permittivity profiles, which is a clear indication of the presence of malignancy. Hence
microwave tomographic imaging is proposed as an alternate imaging modality for early
detection ofbreast cancer.