ABSTRACT. This paper proposes a modified Yagi-Uda antenna with multiple bands and increased gain for wearable applications. The proposed design consists of a coplanar fed microstrip Yagi antenna backed by an AMC substrate and a ground plane which shows an effective triple operational bandwidth. The AMC is designed to operate at triple bands of 3.4 GHz, 7.1 GHz and 9.5 GHz and the performance comparisons are carried out with and without using AMC substrate. The AMC layer comprises 2 ×3 unit cells to form the back plane reflector for Yagi antenna. The proposed antenna exhibits 2.6%, 2.5% and 5.42% low impedance bandwidths at 3.84 GHz, 4.31 GHz and 6.02 GHz frequency regions, respectively. The overall gain enhancement of about 5 dBi is achieved and shows endfire characteristics. The proposed antenna with high gain is a potential candidate for RFID, defence and several medical applications.

ABSTRACT. GaAs based Photoconductive antennas (PCAs) have widespread industrial uses as terahertz (THz) emitters. It is now well known that a periodic metallic structure at the edges of the antenna electrodes, similar to plasmonic PCAs, can extraordinarily increase the antenna performance. Here, we have described that Interdigitated-Slot Photoconductive Antennas (IPCAs) can be a better THz generator than no-slot IPCAs because of its higher screening electric field. IPCAs have been simulated using CST MWS software. Having a teeth length of 20 µm, the width of 8 µm and a slot of 2 µm in the center, the reflection coefficient of -33 dB at 4.65 THz with 0.515 THz has been achieved, whereas, with two slots around the center, the reflection coefficient is -17 dB at 2.84 THz. The result shows how frequency tunability and dual-band radiation can be achieved by optimization of antenna parameters. These micro antennas may be the future of several applications.

ABSTRACT. With an increasing number of subscribers to the terrestrial cellular and/or satellite based services, and a resultant rise in the demand for the data rate, there is an urgent need of advanced signal processing schemes that improve the power and the spectral efficiencies. Digital beamforming using an array of antenna elements is one such technique. When multiple co-channel signals arrive at an antenna array, the digital beamforming techniques, based on advanced signal processing algorithms, improve the array's Directivity in the direction of the Signal of Interest (SoI) while minimizing the array gain in the direction of the Signals Not of Interest (SNoI). The beamforming weights are estimated either using supervised (non-blind) learning methods or unsupervised (blind) methods. The main focus of this paper is on a survey of the digital techniques of beamforming and identifying/summarizing the merits and the drawbacks of each technique. The objective is to summarize the current state of the art for a judicious selection of a suitable technique for the application of interest.

ABSTRACT. In this paper, we investigate the effects of placing multiple parasitic patches symmetrically in the feed-section, on the port-to-port mutual coupling in UWB MIMO antenna elements with very close edge-to-edge spacing (0.02\Lambda at highest operating wavelength \Lambda)). Ansys HFSS based simulations confirm that by strategically tuning these patch dimensions, one can achieve average 6-8 dB mutual coupling reduction in desired high frequency bands around 6.8 GHz and 9.4 GHz, without adversely affecting the impedance-matching/VSWR performance. Furthermore, for the first time in such UWB monopole systems, we determine the envelope correlation coefficient (ECC) in realistic Gaussian/Uniform propagation scenario for a wide range of elevation angles and angular spread of incoming signals, thereby demonstrating the intrinsic connection between port-to-port coupling and far-field spatial correlation performance.

ABSTRACT. The performance analysis of conical Dielectric Resonator Antenna (DRA) with various feeding techniques is presented in this paper. To study the performance of the proposed conical DRA various parameters like, DR height, size of ground plane, upper and lower radius of conical structure are varied and the consequent results are tabulated. For all the feeding techniques, the proposed DRA resonates in the X-band (8-12 GHz) range and the peak gain obtained is above 6dBi.

ABSTRACT. This paper reported a compact Cognitive Radio (CR) antenna system that contains an ultra-wideband (UWB) sensing antenna and a narrowband (NB) communication antenna. The UWB sensing antenna is designed using a tapered fed monopole. It senses over a frequency band 2.2- 11 GHz. The NB reconfigurable antenna operates at 3.854, 4.619, 5.2, and 6.095 GHz. Two ports of the module exhibits less than -15 dB isolation over the entire operating band. The proposed antenna can be used for satellite communication in the C-band (both downlink and uplink), ISM/WLAN, 5G and public safety wireless communications.

ABSTRACT. In this paper, the design of a Conformal antenna for X-band is presented. The effect of curvature on the antenna parameters due to conformability of patch over the different nonplanar shapes is studied. The frequency response and gain are studied as a function of the radius of curvature.

ABSTRACT. The design and development of a triple-band dual-polarized substrate integrated waveguide (SIW) antenna is proposed in this paper. A T-shaped SIW cavity is conceived. The two mutually perpendicular slots etched on the top metallic surface generate two orthogonal linear polarizations (LP). One of these slots is etched on the longitudinal arm which resonates at 14.75 GHz. The other slot on the transverse arm results resonances at 13.14 GHz and 14.35 GHz. The antenna exhibits a gain of about 4.7dBi, 5.3dBi and 6.1dBi at 13.14 GHz, 14.35 GHz and 14.75 GHz respectively. The 3dB beamwidths are about 74 x 85.

ABSTRACT. In this report, we present a graphene-based patch antenna. The proposed antenna comprises of a single layer graphene patch placed on the top of metal-backed dielectric (SiO2). The proposed antenna is excited with impedance-matched proximity feed technique. The antenna provides a wideband in mid-infrared frequency regime from 3.25 THz to 6.20 THz with a minimum reflection coefficient of -38 dB. Here, we obtain a wideband of frequency of operation with a maximum gain of 8.66 dBi at the resonating frequency of 5.26 THz. Application of the proposed design is found in spectroscopy, indoor communication, etc.

ABSTRACT. In the proposed work, a novel compact Microstrip Bandpass filter is designed using metamaterial structure. Symmetrical Split Ring Resonators (SSRRs) are periodically loaded on the transmission line which are located closely to the conductor strip and vias are conducted from strip to ground plane. Band Pass Filters (BPFs) are often used in wireless systems to eliminate and suppress counterfeit signals from undesired frequencies. By proper design, pass-band response with wide bandwidth and compactness is obtained through the implementation of dual square symmetric split ring resonators along the microstrip transmission line. The proposed filter operates in the X-band between 9.2-11.7 GHz, with Fractional Band Width (FBW) of 23.8%, with a rejection which can reach up to 39 dB at the center frequency and with an insertion loss of 0.5dB to 1dB.

ABSTRACT. In this paper, wide scanning beam antenna is designed with substrate integrated waveguide (SIW) Technology. This wide beam SIW antenna works as dielectric filled rectangular waveguide slot antenna and has an operating mode at transverse electric (〖TE〗_10) . The rectangular slots on the top layer are designed according to rectangular waveguide slot theory, the distribution of electric field in slots are analyzed by equating to magnetic current. The entire design is carried out in XZ-plane and it resonates at frequency of 20.3GHz, with gain of 11.64dBi over a bandwidth of 0.5GHz. The scanning range in elevations plane at φ=0 and φ =90 are -500 to 510, -150 to 130 respectively. To observe beam in different direction of 1x4 array SIW antenna is designed and shifting of beam is observed over the wide scanning range by providing input phase-controlled mechanism.

ABSTRACT. In this paper, authors have investigated a simple, low profile, probe fed, shorted rectangular microstrip patch antenna with air gap inserted between substrate (with relative permittivity of εr = 4.4) and ground plane for improved impedance matching , and CP-XP isolation in both H and E planes. In each corner of the patch, a hanging post or pin has been put. It has been observed that both the shorting post and the hanging posts have a strong influence on improving impedance matching and reducing cross-polar radiations from the antenna. Around 21 dB peak CP-XP isolation is achieved in H plane. The H-plane and E-plane beam-widths of the proposed antenna are 72° and 83°.

ABSTRACT. In this research paper, a circularly polarized IRNSS (Indian Regional Navigation Satellite System) receiver antenna is presented using characteristic mode analysis. The proposed antenna has been designed for S-band (2483.50- 2500.00 MHz) with 16.5 MHz bandwidth for IRNSS receiver application. CMA has been used to determine the optimum feed location on antenna to obtain circular polarization for excitation of two orthogonal modes (TM10 and TM01) with equal amplitude and 90º out of phase. The proposed antenna uses probe feed configuration and design using dielectric laminates FR4 (dielectric constant is 4.3 and loss tangent is 0.025). The axial ratio bandwidth (< 3 dB) of the proposed antenna is obtained from (2431.4 to 2562 MHz). The aim of this antenna to improve the designing of antenna technology so as small in size, less complex, better-improved parameters and easy to designing and integration with circuits.

ABSTRACT. In this article, a new scheme for Bandwidth and gain enhancement of Rectangular Microstrip Patch Antenna (RMPA) array, and Rectangular Dielectric Resonator antenna (RDRA) array is proposed for X-Band communication. A 1×4 element RMPA array resonates at 9.697 GHz with impedance bandwidth of 12.16 % (10.47 – 9.29) GHz. Whereas the similar size of RDRA array resonates at 9.69 GHz with impedance-bandwidth of 14.03 % (8.66 – 10.02) GHz. The RMPA and the RDRA array have the gain of 8.9122 dB and 8.7969 dB at the corresponding resonating frequencies, respectively. Circular slots are in each element of the array introduced to achieve better impedance - bandwidth. The ARMPA array with circular slot resonates at 9.39 GHz with impedance bandwidth of 13 % (10.29 - 9.07) GHz, having a gain of 9.7752 dB. Similarly, the ARDRA array resonates at 9.899 GHz with impedance-bandwidth of 15.35 % (10.20 – 8.68) GHz, having a gain of 9.5541 dB. All the antenna parameters such as VSWR, Impedance, Gain, Directivity, Efficiency, etc. are investigated in this paper. The simulations for various antenna designs have been carried out using Ansys HFSS 2015 software.

ABSTRACT. Abstract— In modern wireless communication the need of smart antenna arises to address the challenges like limited capacity in allocated spectrum and signal fading due to propagation environment. To achieve the maximum signal quality towards the desired direction is the greatest deal. Therefore, antennas play a vital role in receiving the signal with desired quality and also transmit the signal energy with desired directivity. To achieve high gain in any given direction, antenna arrays are used and it is possible only with the electronically steerable arrays, which are crucial for modern wireless communication. The smart antenna uses signal processing techniques in such a way that desired signal can be spatially filtered out from the wireless channel with improved gain. Therefore, the quality of the signal reception may be enhanced by changing the directionality of radiation pattern in response to the signal environment. Our focus is to design a smart antenna system that generates desired radiation characteristics with higher directivity towards user direction and nulls in certain interference directions by reducing the side lobe levels by using the adaptive beam forming techniques. It is also proposed to develop the new energy model with the proper selection of inter element spacing between the antenna elements varies from 0.5 λ to 1 λ with the calculation of SNIR.

ABSTRACT. A triple-band metamaterial-based microstrip antenna for WLAN and WiMAX applications is proposed in this letter. The antenna consists of a rectangular microstrip patch on the foreground and two metamaterial unit cells etched on the bottom ground plane. Antenna and ground plane are printed on FR4 substrate (with the ϵr value of 4.4). The proposed antenna operates at three frequency bands, which are 2.65GHz-2.9GHz, 3.17GHz-3.75GHz, and 5.55GHz-6.1GHz. The radiation pattern is omnidirectional for two of the three bands and close to omnidirectional for the third band, which makes the proposed antenna a good choice for WLAN/WiMax.

ABSTRACT. A novel design of CPW fed fractal antenna for wideband applications is proposed. It contains two iterations of modified inner tapered radiator and partial rectangular coplanar waveguide ground plane. It has an operating impedance bandwidth ranging from 5.6-20.5 GHz (114%) and peak gain 4.5dB. The overall substrate volume is 18.5×8.5×1.524 mm3. It has advantages of wider bandwidth, compact size, and desirable radiation characteristics.

ABSTRACT. This paper presents on the design and working analysis of a modified compact patch antenna with enhanced bandwidth for X/Ku/K/Ka-band applications. Four square cuts at the four corner of the patch and slits at three faces have been incorporated in this configuration to enhance the bandwidth as well as gain of the antenna. The antenna modelling is carried out according to arrangements and procedure so that it operates over the multiple frequency bands viz., 10.05-11.85 GHz, 15.37-16.17 GHz and 17.10-34 GHz. The maximum return loss of 40 dB has been obtained at 25.36 GHz while the maximum gain of 7.12 dBi has been realized at the same operating frequency and also it exhibits endfire radiation characteristics. This antenna can be employed for X/Ku/K/Ka band applications like radar, molecular rotational spectroscopy and satellite communication.

ABSTRACT. Being having many advantages of microstrip patch antennas, nowadays these also have applications in biomedical field (for detection of cancer). As EM radiations are hazardous so direct experiments on human body and electromagnetic radiation is impossible. So this paper focused on a breast model to detect the presence of tumor inside it along with antenna structure as radiating source. HFSS simulation software is used for designing and simulation part. Antenna is resonating at 2.46GHz in frequency range (2.41-2.5 GHz) of ISM band suitable for medical purpose. Two models one having microstrip patch antennas along with breast model without tumor and other with tumor are designed simulated and their radiation properties are compared. For cancer detection near E-field results are important so near E-field plot for the two models are shown in this paper. The differences in these results of two models can be used to diagnose tumor.

ABSTRACT. This paper demonstrates the scan blindness removal in C-band multilayer microstrip phased array antenna using uniplanar compact electromagnetic bandgap (UC-EBG) structure. Unit cell approach has been adopted to compute electromagnetic band-stop range of UC-EBG structure. The proposed design of UC-EBG structure shows electromagnetic bandgap of 4.6 GHz to 5.3 GHz. 16 elements linear aperture coupled microstrip array antenna embedded with UC-EBG structure has been designed, developed and tested. The active reflection coefficient (ARC) of linear array antenna has been measured to detect scan blindness and its removal. Scan blindness removal has also been demonstrated by far field characterization of linear array antenna in scanning mode. It has been established that, scan blindness appearing at 20deg-22deg scan angles, in absence of UC-EBG structure, can be removed by embedding UC-EBG structure between array elements. The full wave simulations of UC-EBG structure and antenna structures have been carried out using Ansys HFSS 17.2 respectively.

ABSTRACT. A W-band reflector antenna mounted in a 6-unit CubeSat is analysed. The analyses show that the effects of the CubeSat structure on the performance of the antenna are significant, both on the peak gain and side-lobe levels while the impact on XPD performance is less significant.

ABSTRACT. This paper reports design and development of Monopulse Tracking Feed installed in Ground Station for Satellite pointing and Tracking. Tracking feed is optimized at 19.7 GHz. Null depth w.r.t Sum Peak measured in Azimuth and Elevation planes is > 45 dB. The Azimuth and Elevation error channels are combined using a Riblet Short Slot coupler. Combining error channels will reduce one full channel in tracking receiver saving real estate and power. Phase matching of error channels before combining is done using tapered waveguide sections. This feed is successfully integrated with a Cassegrain Reflector and is used to track Satellites with very narrow beams.

ABSTRACT. In this paper, a light weight high gain left hand circularly polarized microstrip patch antenna for satellite telemetry application is presented. This antenna is suitable on Anti-Earth Viewing (AEV) side of GEO satellite to fill the void created by Earth Viewing (EV) antenna maintaining same polarization, thus ensuring a near omni directional coverage. Moreover, signal ambiguity due to interference in the overlap region of EV and AEV antennas can be avoided by means of high gain antenna. Hence, a circularly polarized high gain antenna in stacked configuration with three truncated patches has been designed and fabricated. It has return loss better than 15dB at resonant frequency and a peak gain of 10.5dBi with 0dBi coverage of ±45degrees.

ABSTRACT. A novel circular polarized broad beam antenna is proposed at Ka-band for the Low-Earth Orbit (LEO) satellite data transmission. This antenna is designed to support an operational bandwidth of 3.5 GHz at a central frequency of 24.25GHz with an axial ratio of 1dB, wherein it can be used for both data upload and download applications. This antenna comprises of choked horn, waveguide septum polarizer and waveguide transitions. The antenna model is having a gain of -4dbi for ±85⁰ coverage with return loss better than 15dB. The modes at input and radiated ports are simulated, their transformation is analyzed and explained with mode configuration plots.

ABSTRACT. Abstract: This paper presents, design and development of dual polarized edge fed and aperture coupled stacked microstrip patch antenna array. Stacked elements are designed on RT Duroid 6002, upper patch is suspended on bottom side of top most layer and lower patch on top side of middle layer. The 4×8 antenna array is designed using four 2×2 sub arrays with two independent power divider network. The edge fed power divider network is connected to lower patch and aperture coupled power divider network is below ground layer. The analyzed return loss is better than 23dB in the frequency band of interest (3.60-3.64GHz). Measured return loss of the array is better than 17 dB in both polarizations over the band. Bandwidth for 20 dB return loss for both port is 7.5 %. Measured Gain of antenna at 3.62GHz is 22.5dBi for V-polarization and 22.6dBi for H-polarization, radiation patterns matches well with simulated.

ABSTRACT. This work presents the design and analysis of a compact composite right/left-handed transmission line (CRLH-TL) loaded antenna useful for small satellite applications at 4.2 GHz. The antenna is comprised of two pairs of CRLH-TL radiators orthogonally placed in a rotating fashion for obtaining circular polarization (CP). The novelty behind the intended CP antenna design is the generation of improved 3-dB AR beamwidth. Using the above concept a miniaturized antenna of size 30 × 30 × 1.27 mm3 is designed and fabricated. The intended antenna provides an improved CP beamwidth (ARBW< 3dB) and gain greater than 1.42 dBi for theta = ±600 and for all phi values (phi = 00 to 3600) at 4.2 GHz. The antenna provides S11 bandwidth of 2.44% (4.13–4.232 GHz) and axial ratio bandwidth of 1.19% (4.17–4.22 GHz). Also, the antenna provides a maximum gain of 5.46 dBic and efficiency >93% by maintaining the antenna compactness and low profile (0.017λ0). Hence the proposed CRLH-TL loaded antenna is suitable for work in modern small satellite applications.

ABSTRACT. This paper demonstrates the effect on equivalent circuit modeling of a square loop artificial magnetic conductor (AMC) when strip width of one of the edge of the loop is varied. The unit cell dimensions, the inter-element spacing, the substrate properties and wave incident angles are considered for circuit model simulations and variations are explored. The square loop with different strip widths is chosen, in order to analyze the effect on TE and TM incident wave. Different correction factors for permittivity are required to validate modeling with measurements in TE and TM wave propagation through AMC. Rejection bands obtained for TE and TM wave are different and do not overlap with each other. The results obtained from the circuit simulations are compared and validated with the electromagnetic full wave simulations results and measurements done with compact UWB antenna in an anechoic environment.

ABSTRACT. This paper presents a design approach to achieve the operational frequency ranging from 40MHz to 160 MHz with VSWR <3 and 5 dBi realized gain in prefixed antenna size of 30 cm width and 100 cm height. A body of revaluation (BoR) monopole antenna was optimized with respect to lowest frequency (flow) for the specified parameters resulting in lowest achievable frequency of flow 50.21 MHz. To improve flow, capacitive hat and parasitic ring are used without changing surface profile of the BoR monopole, resulting in flow=40 MHz.

ABSTRACT. In this paper, finite-difference time-domain (FDTD) method is used to analyze the reflection characteristics of three wideband slot antennas – the basic designs for S and C-bands and a directive design for the C-band. The input impedance and corresponding return loss responses are computed. Near-field plots of the slot antenna are generated to identify the operating mode. All results are compared with that of ANSYS HFSS simulation and are in good agreement.

ABSTRACT. This paper presents the analysis details of monopole antenna for Emergency Position Indicating Radio Beacon (EPIRB) for Cospas Sarsat search and Rescue System. Change in antenna radiation pattern with respect to variations in antenna length, the height of antenna from the antenna ground, ground plane dimensions and beacon floating levels are simulated and analyzed in detail. Test results of an optimum configuration that can meet Cospas Sarsat specifications for 406MHz EPIRB are also presented.

ABSTRACT. Key aspects of optimization algorithms when applied to challenging antenna design problems are reviewed. As an example of such an algorithm, the Multi-level Coordinate Search (MCS) global optimization algorithm is highlighted as a good candidate algorithm. We present two comparisons which illustrate that MCS can be beneficial compared local-search algorithms as well as other popular global algorithms.

ABSTRACT. This paper presents the design of 3 m Cassegrain antenna fed by a dual-band beam waveguide. Antenna has been designed to achieve 60 % aperture efficiency and 90% beam efficiency at 0.225 THz and 0.338 THz bands. Gaussian beam parameters like, beam waist and radius of curvature are computed for fundamental Gaussian beam mode at input and output of mirror equivalent lenses for initial design of multireflector antenna. The simulation results of the beam waveguide antenna are presented for various electrical parameters such as beam-width, cross-polar level, side lobe level and efficiency. The realization, assembly and alignment challenges at terahertz frequencies are also discussed. This antenna has been designed for ground telescope to reveal the properties of molecular clouds in the Milky Way Galaxy for astronomical observations.

ABSTRACT. An innovative multi-directional beam-steering shaping technique for offset Gregorian reflector antenna is described in this paper for getting enhanced peak-gain. This technique is applied at relatively shorter-focal length reflector antenna, which could accommodate easily on shorter height spacecraft bus. Shaping technique reduces steering gain-loss over larger steering angle. In Gregorian antenna, feed horn and sub-reflector are fixed and only main reflector antenna is moving. The results of Gregorian antenna obtained with physical optics method (PO) is compared with those obtained using method of moments (MoM) method with good matching.

ABSTRACT. In this paper, the design of X-Band dual circularly polarized data transmission feed for a 3.6m Radial Rib Antenna (RRA) is presented. The RRA as a common reflector in cassegrain configuration can be used for both payload and data transmission application. The configuration comprises of a nine antenna feed system where the eight linear polarized elements provides payload data and the extreme 9th element is used to download the payload date to ground stations. The data transmission is in dual circular polarization for frequency reuse. The designed central feed has good circularly symmetric co-pol patterns with a taper of -1.7dB at ±17.5⁰ and isolation better than 20dB over 10% bandwidth. This element provides cross–pol isolation by better than 25db at the required frequency (8-8.4 GHz) to support dual circular polarization for frequency reuse application. The criticalities involved in the design associated with the feed location are thoroughly discussed in this paper.

ABSTRACT. This Paper deals with design and development of Symmetrical Cassegrain Unshaped reflector in Q/V band for high speed communication. This paper shows the design of compact high performance Transmit and Receive dual feed dual beam antenna with high XPI with low losses. This paper presents the first Q/V band antenna on board ISRO’s Spacecraft. This paper also shows the measured results of EOC gain of 43dBi and XPI of -28dB over the allotted frequencies in Q/V band.

ABSTRACT. This work proposes a reflecting meta-surface with reduced Radar Cross Section (RCS). Hexagonal supercells pack the surface. Each supercell contains non-resonating remodeled Jerusalem Cross meta-cell arranged appropriately to give linear reflection phase. This arrangement of phased elements reflects diffused scattering of incident waves at 9.5GHz, 10GHz, and 10.5GHz. Numerical and measured monostatic RCS results of meta-surface compared to equivalent metallic plane plate shows approximately 15dBsM reduction. This has application potential for X-band stealth technology.

ABSTRACT. ISRO has launched GSAT-29 payload which hosts several technological payloads including Q/V band transponder in 38-43 GHz band with two interconnected spot beams. For communication between these two beams, Q/V Band Earth stations are established. This paper presents implementation and testing of Q/V band Earth station for SATCOM applications. The major challenge of the Earth station establishment is the stringent requirements of pointing and tracking accuracy and non-availability of Q/V band beacon from the satellite. We have successfully designed, implemented and tested a novel approach for pointing and tracking of Q/V Band earth station in the absence of Q/V Band beacon.

ABSTRACT. This paper presents two cavity backed slot antenna arrays with continuous side walls implemented using planar PCB fabrication technology. A square waveguide resonator is excited in the TE220 mode. In the first antenna, a microstrip line feed in the same plane excites the array, while a vertical microstrip-to-waveguide transition excites the second array antenna. In both of the antennas, four radiating slots are etched on the top wall of the waveguide cavity to obtain radiation in broadside direction. Chosen configuration of the antennas enable easy fabrication using the standard PCB fabrication technology. Measured 10 dB impedance bandwidths of the antennas are 175 MHz and 335 MHz, respectively, at 24 GHz. The broadside gain for both the antennas is more than 9.5 dBi.

ABSTRACT. Steering the main beam of a time modulated antenna array (TMAA) with reduced side lobe level (SLL) is proposed in this paper. Linear antenna array of 16 and 18 isotropic elements are considered here with time modulation. Predefined switching scheme has been used to generate the desired radiation pattern at fundamental and multiple harmonic frequencies to achieve beam steering. A modified version of particle swarm optimization (PSO) with wavelet mutation is used to lower the overall side lobe level. Switching time sequences and inter element spacing between radiating elements are optimized to get the desired radiation pattern with minimal changes in first null beam width (FNBW).

ABSTRACT. In this paper, a bow-tie shaped slot antenna is proposed to enhance the bandwidth of the narrow band antenna while maintaining the same antenna gain. The proposed antenna utilizes the substrate integrated waveguide (SIW) technology. It covers the 10 dB impedance bandwidth of 620 MHz (8.76-9.38 GHz). A prototype is proposed for X Band and has been compared with the existing structures.

ABSTRACT. This paper presents the configuration study for different Thinned array configurations like X, Y and T. Based upon the thinned array performances, Y type thinned array has been selected to design and develop planar array antenna at L- band. This antenna has been used for Synthetic Aperture radiometer. A new type of strip probe fed patch has been used as single antenna element. These radiating elements have been used to form a Y type thinned array having 8 elements in one arm. The simulated and measured performance on return loss & radiation parameters have been presented.

ABSTRACT. The proposed paper presents the design and development of a 16X8 Phased array antenna along with a Wilkinson based feeding network (A 128-way equal Power divider) for RADAR application based on a cavity backed patch antenna element. This has been implemented for an operation over the X-band, 8.6 GHz – 9.5 GHz with a scan range of ± 45⁰ in the H-Plane and ±30⁰ in the E-Plane. The simulated results show a return loss > 10 dB, 3 dB beamwidth of 12.1⁰X6.2⁰ in H-/E-planes with a gain of 26.4 dB over a bandwidth of ~10% in X-band.

ABSTRACT. This paper presents the design of broadband planar slotted waveguide array (SWA) antenna, excited with novel waveguide feeder network which also functions as broadband impedance matching network. A 4 x 12 narrowband longitudinal shunt slotted waveguide array working at X-band, is designed and integrated with 1:4 waveguide feeder network which offers the broadband impedance matching. Design of such broadband SWA antenna requires computation and matching of active parameters at SWA antenna ports and waveguide output ports. Active reflection coefficients and active normalized admittances have been computed using simulated S-parameters of SWA antenna and waveguide feeder network. Simulation of proposed antenna has been executed using 3D electromagnetic simulator. Prototype of 4 x 12 broadband SWA antenna is also developed and characterized to validate its performance. 6.3% bandwidth of S11 < -17 dB and 24.2 dBi boresight gain at 9.6 GHz have been achieved in measurement. Comparison of simulated and measured results is presented and found in good agreement.

ABSTRACT. A slot array design for a gain more than 44dBi RLSA is shown in this manuscript. A conventional slot array design procedure based on the Method of Moments was adopted, however needed to modify to adapt with a large number of radiating elements and a multilayer structure of the substrate. A fast analysis method based on a simplified however reliable equivalent model of the multilayer waveguide is developed to estimate the performance. Several RLSAs with a diameter of 900mm are fabricated and measured. In the optimum case, a directivity of 48.3dBi correspond to 73% aperture efficiency is obtained at 31.9GHz, where the measured gain is 44.6dBi.

ABSTRACT. Broadband communication using satellites requires the use of Ka-band. Services of this type are now emerging all over the world, some with capacities in excess of 100 Gbps. However, as the radio bandwidth resources become exhausted, high-speed optical communication is required as well. The National Institute of Information and Communications Technology in Japan researches and develops the next generation of space communication technology. A hybrid satellite communication system using RF and light-wave communications is being studied. There are three kinds of RF antennae and one optical antenna systems for the hybrid high-throughput satellite communication system, which will be embarked in space. Here, the research and development activities of the National Institute of Information and Communications Technology are introduced.

ABSTRACT. New antenna technologies have unlocked a new class of missions using CubeSats for Earth Science or Deep Space operations. This class of small satellites have historically been mostly used as teaching tools allowing students to design and test small satellites and develop space experiments. With the rise of new game-changing antenna technologies, overcoming their small size and need for high gain, they can now be used beyond Low Earth Orbit (LEO). Over the past 5 years, technologists at the Jet Propulsion Laboratory have designed, tested and successfully flown these innovative Smallsat antennas, enabling new telecommunication and science achievements.

ABSTRACT. A new all-metal dual-frequency RHCP high gain antenna is under development at NASA’s Jet Propulsion Laboratory for a potential Europa Lander. The antenna is mainly made of metal so it could survive the harsh environment conditions (i.e. very low temperature and high radiation and ESD levels). The antenna is also flat to meet drastic volume constraints and has efficiencies higher than 80% at both the uplink and downlink X-band Deep Space frequency bands. This antenna is a key component for the potential mission enabling Direct Link to Earth (DTE) from and Direct-from-Earth (DFE) to the lander without any relay.

ABSTRACT. This paper will first explain the concept of a space solar power system （SSPS) , which includes a transmitting antenna called a spacetenna and a receiving antenna called a rectenna. Both antennas are extraordinary in size. Then, the current study status of various kinds of SSPSs and relevant antennas. The paper possibly gives some hints of new research topics to readers.

ABSTRACT. Result oriented techno-business leader with over two decades of global experience in strategy formulation, pioneering and managing large and complex business and IT transformation programs, setup and deliver large IT application portfolios, Infrastructure and Operations, organisational and operations setup, budget implementation, relationship management, team leadership, strong acumen in product roadmap and customer management for sustainable growth. Professional highlights are: • Expertise in institutionalising policies, processes and standards. • Build and lead high performance teams in Technology and Programme management areas. • Digital Technology and business solution evangelisation and setup Centres of Excellence (CoE). • Experienced on Digital Technologies - Big data, Blockchain, IoT and AI. • Created of EA blueprints and enterprise Transformation, experience in TOGAF • Large-scale and complex portfolio governance. • Strong experience in Life and General Insurance, BFS and Government sectors • Successfully managed Digital transformation programmes with large Insurers • Driving innovation, building new products and creating new ventures. • Enterprise Architecture – Set policies to set strategic direction, successful execution experience. • Setting up large-scale global operations. • Executive customer engagement. • Leadership and organisational skills developed to lead and manage large global team. • Spearheaded project delivery with tight timelines in a complex environment with latest technologies. Expertise: • IT and business strategy & execution • Digital Enterprise • Enterprise IT

ABSTRACT. Ravikiran Annaswamy is Founder and CEO of Numocity Technologies. He is incubating various innovative products using analytics and deep learning. His current business focus is on bringing Electric Mobility to Indian market and has launched various technology products like Fulcharge.com in this space. He works closely with global programs like Founders Institute (Fi.Co) and Unreasonable Institute as Mentor and Coach for early stage startups. He is on the global team of IEEE 5G and is responsible for vision & strategy for future applications and services like Tactile/Haptic Internet, IOT, AR, VR Applications. He has over 24 years of business experience as Entrepreneur and as Business Leader at Nokia Siemens Networks and Siemens AG. He was Business Head for Indian market, led Global Product Management and was General Manager for BSS Solutions. He championed Intrapreneurship by working as Innovation head for Bangalore site of Nokia Siemens Networks. He has vast experience of launching successful technology solutions for global markets, mainly in the area of Analytics and Marketing automation, Online Billing and Charging, Innovative 3G/4G applications, Multimedia and Security Solutions. He is an engaged Professional volunteer, was the Chairman for IEEE Bangalore section (2014-2015), Industry Relations for IEEE - Asia Pacific (2014-15) and Secretary for IEEE Asia Pacific (2015-16). He is currently a board member and Vice President - Memberships and Marketing for IEEE TEMS. He is a thought leader and speaker at various prestigious international business conferences. 

He has done his MBA from Indian Institute of Management, Bangalore and has graduated from UVCE Bangalore. He has been recognised for his work by several awards: Siemens Director’s award for Innovation, IEEE Bangalore - Best volunteer award, Runner up at AIMA’s National Contest for Young Managers and Asia finalist at Global Social Venture Competition conducted by Berkley Haas school of business.

ABSTRACT. Shantanu Bhatawdekar is Programme Director, DMS & Associate Director, EDPO at ISRO Headquarters, Bangalore. He is primary responsible for steering ISRO’s programmatic activities and inter-ministerial interactions related to space enabled support for Disaster Management in India. He also coordinates activities of earth observation applications and promoting its utilization for governance and development. He has been contributing to various EO missions of ISRO from the point of view of user requirements, payload definition and applications supporting EO community. He has more than 30 years of experience in the areas of Remote Sensing, Image Processing, GIS and Decision Support Systems (DSS). He has worked in various capacities as Project Director, Deputy Project Director, Project Coordinator in conceptualizing and designing software packages, information systems and Decision Support tools, which include Crop acerage& production estimation, Information System for Natural Resources Management, DSS for Fertilizer Demand Estimation & Management, Web based DSS for Radiological emergencies, DSS for Locust impact minimization for Government of Kazaksthan, Disaster Management Support shell. He has represented ISRO in number of international forums and technical meets.

ABSTRACT. SELCO sees the pressing need to develop a fertile environment to enhance sustainable energy access solutions for the poor. This energy access increases incomes, improves quality of life, and alleviates poverty, turning energy consumers into asset owners. Last mile energy solutions have clear commercial viability, and SELCO works to combine technical and non technical aspects focused on alleviating poverty in a sustainable manner. Today, SELCO is an umbrella of organizations, each tasked to address gaps in the energy access ecosystem. SELCO India established in 1995 runs grassroots operations which sell, install, and service decentralized energy solutions like solar lights systems for households, institutions, digital education, livelihood appliances etc. financed by local financial institutions. SELCO Foundation established in 2010 is an open-source innovation research lab for replicable social innovations across areas: livelihoods, education, and health. SELCO’s incubation program created in 2012 nurtures and catalyzes aspiring clean energy enterprises that deploy and maintain sustainable solutions for underserved communities. Finally SELCO Fund registered in 2016 is an impact fund that seeks to deploy patient capital such as equity or debt to last mile energy access enterprises. SELCO operates at every level of the system and at every point in the supply chain, to build an ecosystem that increases accessibility, affordability, and appropriate renewable energy solutions for the poor. Collectively SELCO has so far impacted over 2 million people. Harish, a graduate from the Indian Institute of Technology, Kharagpur and a Masters and PhD from University of Massachusetts, US. In recognition of his vision and the efforts of SELCO, they have been awarded national and international awards including