Vivekanand Tiwari

A comparative analysis of remote sensing image classification techniques

In this paper, we have compared the accuracy of four supervised classification as Mahalanobis, Maximum Likelihood Classification (MLC), Minimum distance and Parallelepiped classification with remote sensing Landsat images of different time period and sensors. We have used Landsat Multispectral Scanner (MSS), Thematic Mapper (TM) and Enhanced Thematic Mapper+ (ETM+) images of 1972, 1998 and 2013 respectively of Jaipur district, Rajasthan, India. Accuracy has been calculated using Producer accuracy, User accuracy, Overall accuracy and Kappa statistics. We have found that remote sensing images with a different time period and sensors, when classified with supervised algorithms produced different results. Minimum distance classification produced better accuracy with Landsat MSS image than other three classifications while Maximum Likelihood Classification produced better accuracy with Landsat TM and ETM+ images than other three classifications.

Prediction of Urban Sprawl Using Remote Sensing, GIS and Multilayer Perceptron for the City Jaipur

The population of India has rapidly increased from 68.33 million to 121.01 million from 1981 to 2011, respectively. It is estimated that by the year 2028 India will hold the largest population of the world. The prompt upsurge of the Indian population will force people to migrate from the rural area to the mega cities, to avail basic amenities. The enormous migration will increase the demand for more space to live in mega cities and will lead to a situation of unauthorized, unplanned, uncoordinated, and uncontrolled growth, and this condition called as urban sprawl. The key challenge for a planner is to achieve sustainable development and to predict the future urban sprawl in the city. Unfortunately, conventional techniques that predict urban sprawl are expensive and time consuming. In this paper, we have proposed a novel technique to predict the future urban sprawl. We have used an integrated approach of Remote Sensing, GIS, and Multilayer perceptron to predict the future urban sprawl for the city Jaipur up to 2021. We have compared our results with existing techniques like Linear Regression and Gaussian Process and found that the Multilayer perceptron gives better results than other existing techniques.

A Monopole Antenna with Reconfigurable Notched Characteristics from WLAN-band Notched UWB to ITU-band Notched UWB Antenna

This paper presents a monopole ultra wideband (UWB) antenna with reconfigurable notched characteristic. The proposed antenna is capable to switch its resonance from 5.2 GHz centre frequency band-notched UWB to 8.2 GHz centre frequency band-notched UWB applications. It consists of H-shaped reconfigurable parasitic resonator in ground plane to obtain the band notched at 5.2 and 8.2 GHz centre frequency bands by the mean of two p-i-n diodes. The impedance bandwidth enhancement of the antenna is achieved by inserting a slot in the ground plane. The proposed antenna is optimized and simulated using CST—microwave studio software.

A NOVEL FREQUENCY RECONFIGURABLE MONOPOLE ANTENNA WITH SWITCHABLE CHARACTERISTICS BETWEEN BAND-NOTCHED UWB AND WLAN APPLICATIONS

This paper presents a novel frequency reconfigurable monopole antenna that has switchable notch characteristic at center frequency of 5.3 GHz. The proposed antenna consists of a defective ground structure (DGS) to enhance the impedance bandwidth from 3.17 to 13 GHz. The F-shaped parasitic element with three stubs (two vertical and one horizontal) are located on the back side of the radiating patch to achieve the band rejection characteristics from 4.9 GHz to 5.7 GHz. The metallic ground plane structure is connected or disconnected to the F-shaped parasitic element through stubs by means of p-i-n diodes. Experimental demonstration of applications of the proposed antenna structure as 5.3 GHz notched band ultra-wideband (UWB) antenna with all diodes in the OFF-state and as 5.3 GHz radiator for wireless local area network (WLAN) with all diodes in the ON-state is reported. In both the cases, good agreements between measured and simulated return losses, radiation patterns and realized gains are observed.

Compact dual band convexo-concave microstrip patch antenna having bow tie slot with Alteration of Dielectric Substrate for remote sensing applications

Microstrip antennas are one of the most widely studied antenna structures, perhaps due to their inherent properties like compact size, light weight and their capability to get integrated with other circuit components. A three dimensional rectangular slot loaded dielectric (Alteration of Dielectric Substrate) of the antenna for dual-band (S & C) operation has been proposed for remote sensing applications. In this paper, first a single layer convexo-concave patch antenna with a concave bow tie slot is designed and analyzed. Then a superstrate layer is introduced with this antenna. A comparative study between the single layer and multilayer convexo-concave patch antenna is done and it is observed that after the application of a superstrate layer with alteration of dielectric substrate the antenna resonates at two different frequencies 3.17 GHz and 5.34 GHz with a bandwidth of 7 % and 17 % respectively.

Frequency reconfigurable monopole antenna with switchable band characteristics from UWB to band-notched UWB to dual-band radiator

This paper presents a frequency reconfigurable monopole antenna with switchable band characteristics from Ultra-wideband (UWB) radiator to band-notched UWB radiator to dual-band radiator by the mean of three p-i-n diode switches. Three p-i-n diodes are employed in the slots on the circular ring and rectangular patch to make the antenna reconfigurable in three radiating modes: UWB radiator (with all diodes in the ON-state), 5.3 GHz band-notched UWB radiator (with D1 and D3 in the ON-state, and D2 in the OFF-state) and dual-band radiator (with D1 in the OFF-state and D2, D3 in the ON-state) are reported. In all modes of the diodes, good agreements between simulated and measured results are observed.

A novel approach to predict the urban sprawl

The yearly increase in the population of India was 68.33 million in 1981 and grew to 121.01 million in 2011, respectively. It is estimated that by the year 2028 India will hold the largest population of the world. The prompt upsurge of the Indian population will force people to migrate from the rural areas to the mega cities. This enormous migration will increase the demand for more space to live in mega cities and will lead to a situation of urban sprawl. The key challenges are to achieve sustainable development and to predict the future urban sprawl. In this paper, we have proposed a novel model to predict the future urban sprawl. We have used an integrated approach of remote sensing, GIS, and MLP to propose a novel model to predict the future urban sprawl for the city Jaipur up to the year 2051.

Design and development of Orthomode Transducer for X-band frequency

An orthomode transducer for 9.3GHz to 9.5GHz frequency band has been designed and presented here. The Orthomode Transducers are widely used in dual-polarized systems such as radar antennas, radiometers, and communications links. Wherever there are two polarizations of radio signals (Horizontal and Vertical), the transmitted and received radio signal to and from the antenna are said to be orthogonal. This means that the modulation planes of the two radio signal waves are at 90 degrees to each other. The OMT designed here has been able to achieve isolation better than 40 dB and VSWR<;1.42. The commercial software HFSS is used to design the whole structure.

Measuring and Monitoring Urban Sprawl of Jaipur City using Remote Sensing and GIS

The worlds population increased drastically and forced people to migrate from rural area to major cities in search of basic amenities. The majority of the Worlds population are already living in the major cities and it is continuously increasing. The increase in population forced the major cities to expand. Expansion of cities acclaimed more unplanned settlement that leads unplanned growth. This is a global phenomenon that has a direct impact on natural resources. It is the biggest challenge for urban planners to achieve sustainable development. Developing countries like India, where the population is increasing at an alarming pace, require more attention towards this problem. In this study, an attempt has been made to measure and monitor urban sprawl in Jaipur (Capital, State of Rajasthan, India). Built-up area with corresponding population has been analysed over a period of 41 years (1972-2013). Remotely sensed images of 1972-2013 (MSS, TM and ETM+) have been classified using Supervised Maximum Likelihood Classification (MLC) for digital image processing. Shannons entropy has been used to quantify the degree of urban sprawl, and eight landscape metrics have also been used to quantify urban sprawl and its pattern.