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A novel wideband log spiral antenna with superstrate design is proposed for C-band applications. Initially spiral antenna is designed on a 20.4 mm diameter then Minkowski fractals are placed on outer boundary of spiral antenna. The bandwidth of an antenna is improved using Minkowski fractals. Further one more single layer is added as a superstrate design which making the radiation pattern unidirectional. The single layer spiral antenna with fractals has return loss bandwidth of 0.59 GHz and fractional bandwidth of 11.98% where as double layered spiral antenna has return loss bandwidth of 1.34 GHz and a fractional bandwidth of 27.50%. The proposed antennas have a gain varying in the range of 2.5 to 4.64 dBi over the operating frequency band for both the single layer spiral antenna and double layer (superstrate) spiral antenna.

In this paper, a compact log spiral antenna with slots on the spiral arm is designed to achieve wideband bandwidth and compact structure. These circular slots are also providing better impedance matching in terms of lower return loss. The introduction of slots increased the gain of the antenna. The proposed antenna has achieved a fractional bandwidth of 43.83 % over the S-band frequency range from 2.68 to 4 GHz. The radiation pattern is bidirectional along broadside direction. The gain of proposed antenna varies from 2.2 to 3.4 dBi over the S-band frequency range.

This paper proposes the design analysis and implementation of single element, two element and four linearly placed elements implanted on wearable substrate. Effect of FR4 and Jeans wearable substrates are studied with the designed models. The traditional square shaped basic patch antenna is fixed with the dimensions of 20×20 mm2, The base antenna is transformed to two element model assuming both the elements to be similar with the inter element spacing of 34mm. Finally the structure is analyzed for 4×1 linear shaped array. Illustrative comparisons of all three models with both the substrates are evaluated in this work. The overall size of the linear antenna array with inter element spacing is very small compared to the wavelength at the resonant frequency. The structures with the line feeding technique are performed in terms of return loss bandwidth (S 11 ), gain and antenna efficiency using the CST software simulator. Significance of the proposed linear antenna array with Jeans cloth (1.7) is compared with the FR4 (4.4). Novelty of this work lies in performance of wearable antenna array which resonates at frequency of 5.3GHz WLAN application with the high gain value of 13.09dBi.

In the present paper a novel technique is applied to ground plane of patch antenna to reduce the size of the radiating patch and simultaneously increase the gain of the antenna. A rectangular microstrip antenna is designed for Wi-Fi application at 2.45 GHz. Fractal structures are self symmetry structures which can be used for size miniaturization. Sierpinski carpet fractal slots are applied to the ground plane of the rectangular patch antenna working at 2.4 GHz frequency. The results are simulated for first iteration and second iterations of fractal DGS antenna. There is size reduction of the radiating patch is 30.78%, 32.9% for 1st and 2nd iterations fractal slots respectively. The performance of the antenna has also showed improvement.

A novel cross-slot printed wideband conformai antenna is proposed for GPS application. The combination of partial ground plane and cross-slot on the patch are used for bandwidth enhancement. The proposed conformal antenna exhibits a fractional bandwidth(for the definition of −10dB) of 79.28% operating from 1091 to 2524 MHz. The radiation pattern exhibits an omnidirectional pattern and gain of the proposed conformal antenna is 2.37 to 5.33dBi within operating frequency range.

Water is a key resource for life on earth. Clean Drinking water is one of essential human needs. With the increase in urbanization a threat of water scarcity is alarming. This triggers the idea of reuse and recycling of waste water. This paper presents the need for waste water treatment and also gives the brief description of various stages of waste water treatment. The waste water treatment plan works optimally only under certain parameters. Hence sensors can be used at different stages of water treatment for automation. This paper presents the importance and necessity to recycle the waste water and provides a solution for automation of the waste water treatment plant.

Smart cities mission of India gaining popularity day by day. With the introduction of Internet of Things into smart cities the goal of smart cities mission is easy to achieve. One of the key feature of smart cities is Public transport. A smart city should possess an Intelligent public transport system. Today with the lack of appropriate information system in the public transport system, passengers are facing huge problems in the crowded cities. Passengers are forced to wait for long time since they don't know the information of an upcoming Bus or Train reaching to a terminus. With the introduction of technology into the public transport system a passenger can travel with an ease in the city. Here we propose a system where the current position of the buses and the arrival and departure times of the buses can be informed to the passengers via the display boards in the bus terminus or via the app installed in smart phone by incorporating latest technology into existing bus systems. The proposed technology has GPS system that tracks the location of the bus, a sensor incorporated in the bus to know passenger count. The GPS and sensor data is processed by a Raspberry Pi3 computer and then sent to a server. At the Bus terminus this information can be accessed through WiFi/Internet by the passengers.

Nowadays the idea of Smart Cities had become very popular. With the advent of Internet of Things, the concept of smart cities can be readily achievable. An extensive research is ongoing in the field of Internet of Things to increase the quality of services offered in cities and to improve the productivity and reliability of urban infrastructure. Internet of Things is addressing the most common problems faced in cities like availability of car parking and traffic jams. This paper presents an Internet of Things based Parking system for Smart Cities. The proposed parking system contains an IoT module deployed on-site for managing the available parking spaces. A platform provided in the form of portal for booking the parking spaces.

A novel wideband conformal slot antenna is proposed for GPS application. Initially a planar antenna with dumbbell shape slot on three sides of patch is designed at a slightly higher frequency and then the planar antenna is transformed to the corresponding cylindrical conformal antenna with the desired radius of curvature. The antenna used in this study employs a dumbbell shape slot on the three sides of patch. To design the wideband antenna, combination of partial ground concept and dumbbell shape slots on patch is employed. The flexible and higher thermal stable substrate like Rogers RT/duroid 5880 with permittivity of 2.2 and thickness of 0.787 is used. Microstrip line feeding is used in the proposed antenna. The proposed conformal antenna exhibits a fractional bandwidth (for the definition of −10 dB) of 75.94% operating from 1056 to 2349 MHz, which is suitable for all GPS band, GLONASS and GALILEO application. The radiation pattern exhibits an omnidirectional pattern and gain of proposed conformal antenna is 2.09 to 4.9 dBi within operating frequency range.

A novel conformal antenna is proposed for GPS application using Koch fractal geometry. The conformal antenna is obtained by initially designing planar patch antenna at a slightly higher frequency by using Koch fractal and then the planar structure is transformed to the corresponding cylindrical conformal antenna with the required radius of curvature. The Rogers RT/duroid 5880 with permittivity of 2.2 and thickness of the material 0.787mm is used as substrate. Coaxial probe feeding is used in the proposed antenna. The proposed cylindrical conformal is having a bandwidth of 20MHz and also has a peak gain of 5.9dBi at the center frequency of 1.575GHz. The conformal antenna designed on the 60mm radius of curvature at 1.575GHz that can be used for GPS application which can accommodate L1(1.56–1.58GHz) band.

In this study, a dual band-notched ultra-wideband tapered slot antenna is introduced. Here, split ring resonator and balun are used to suppress spurious unwanted bands. The split ring resonator is etched to the certain distance from the excitation point. Hence, one resonance is excited with extended band width. According to the feeding configuration, the stepped microstrip line and slotline connected with circular slot. So, strong EM wave coupling is generated with balun. The electric-field-coupled (ELC) resonator structure is placed inside the circular balun. The size of the tapered slot antenna is 55×40 mm2. The simulation results show that the impedance bandwidth of the antenna is covered an ultra-wideband frequency range (3.1 to 11 GHz) with VSWR< 2 and the band rejection is created at WLAN and ITU band.

In this paper MIMO transmission scheme is analyzed with pre-ordered ZF-SIC, MMSE-SIC and ML detection schemes by transmitting BPSK modulated symbols over Rician-K, Nakagami-m fading channels. Rician-K fading channel is proper medium whenever there is LOS component between transmitter and receiver. Nakagami-m fading is most generalized channel model. it can generate any other channel model by changing shaping parameter m. and BER vs. SNR graphs are generated for Rician factor K = 4, 8. Nakagami m = 1, 1.4 and 1.8 and performance of three detectors is compared.

A compact single probe feed Minkowski fractal boundary patch antenna based on HIS (High Impedance Surface) is proposed for dual band dual polarization operation. Dual band operation with widened bandwidth at each resonating frequency and dual polarization can be achieved by using the combination of HIS and Minkowski fractal curves. The 10-dB return loss bandwidth of lower and upper frequency bands are 13.01% and 4.95% respectively. The 3-dB Axial Ratio bandwidth is 3.4%.

A novel planar and conformal antenna with dual U slot are proposed at 2.41GHz and 2.45GHz respectively. The antenna is designed on RT Duroid 5880 substrate of permittivity 2.2 and thickness of 0.787mm with microstrip inset feed. The proposed planar antenna also has bandwidth of 24.9MHz and has maximum gain of 4.2dB. The planar antenna is transformed to conformal cylindrical of 25mm, 45mm and 60mm radii. The gain values are decreased from 5.9dB to 2.81dB but the bandwidth values varies from 23MHz to 22.1MHz by changing the radius of curvature from 60mm to 25mm. The planar and conformal antenna on different radii has a single band at 2.41GHz and 2.45GHz respectively which is suitable for Wi-Fi application.

In the present work, an optimized approach is described in predicting the current excitations of a planar array geometry for obtaining multiple beam widths in a single aperture using Radial Basis Function Neural Network (RBFNN). The approach utilizes current distributions of uniform, binomial and triangular forms for a 5×5 planar array. The radiation pattern values are given as input to the neural network. The output of the neural network is current excitations of the planar antenna array elements. RBFNN is initially trained with the input-output data pairs and tested and explored for the estimation of current excitations. The network showed a high success rate.

A novel probe feed dual polarized pentagon slot shaped planar antenna is designed and proposed supporting wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) applications simultaneously. Structure comprises of pentagon shaped radiating element along with scaled down slot cut on center of patch, having overall compact size of 40×40mm2. The conventional pentagon patch resonates at 3.5GHz and the modified slot based structure resonates at tri bands of 2.4/3.5/5.2GHz. Effective comparison of antenna with and without pentagon slot is performed to obtain better impedance bandwidth, acceptable gain at operating frequencies and circular polarization at 2.4GHz. The simulated results exhibit the designed antenna operates over triple frequency ranges, fulfilling the standards of WiMAX and WLAN. Gain values obtained are 5.6, 3.2, 2.04dB respectively over respective tri bands. In addition, acceptable radiation characteristics are obtained over the operating bands.

This paper presents a new patch antenna array which generates single, dual and multi bands that are capable of maintaining high performance over a wide spectrum of frequencies. This antenna incorporates a simple and novel single layered pentagonal slot antenna to achieve different resonant bands. For feeding the antenna and array elements, an inset line feed network is used. Structures are realized using IE3D simulation tool and implemented using commercial substrate to meet low cost requirements. Appropriate impedance matching is achieved at different bands of single element, 2×1 linear array and 2×2 planar arrays with proper designed transformation. High impedance bandwidths, moderate gain and better efficiencies are obtained as outcomes from the analyzed configurations, compared to existing designs. Peak antenna gains for three cases are about 5dBi, 6dBi and 9 dBi have been obtained for different resonant bands, respectively.

This paper describes a corrugated antipodal Vivaldi antenna with improved performance by using negative index metamaterial (NIM) of the Archimedean spiral design. A single layer NIM piece is placed perpendicular middle of the two arm of the proposed antenna. The antenna size is 30×60×0.787 mm3 operating at 8GHz. The simulated results of NEVI corrugated antipodal Vivaldi antenna show that the gain and directivity has increased up to 1.2dB and 1dB respectively. The HPBW is increased by 90 with the reflection coefficient less than DIO dB from 4.7 GHz to 11 GHz for UWB application.

Single probe feed triangular patch antenna with asymmetric dual V-shaped slots is designed, fabricated and tested for tri-band applications. The unequal length arms of inner and outer V-slots gives provision to achieve two degenerate orthogonal modes, which lead to circular polarization (CP) at lower and middle bands respectively. The antenna resonates at frequencies of 2.4GHz, 3.5GHz with CP and 5.28GHz with linear polarization (LP). Good agreement obtained between simulated and measured results.

Compact microstrip patch antenna with L-shaped spur lines using Hilbert shaped fractal defective ground structure (DGS) is proposed and investigated for multiband applications. The objective of the paper is to obtain average size reduction of about 72% using resonant frequency shift method with the help of DGS. The impedance bandwidth, gain and efficiency are observed and compared for the proposed antenna with and without DGS. Excellent agreement is found between simulated and measured results.