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A low loss sectorial disk microstrip power divider is developed and employed for characterization of on-board amplifier. Standard topologies employ 4-port directional couplers attached together so as to simultaneously test various parameters such as frequency, power and modulation index for the on-board operations. In case of low power applications simple sectorial disk planar power divider can measure these parameters. The realized divider is totally planar and integrated with multiple measurement equipment for the amplifier characterization. The measured results of the developed power divider show close analogy with the simulated values. The proposed topology is further integrated with the amplifier test bench set-up at C-band for the complete characterization and results are validated with the typical measurement using the standard topology.

Satellite communication has become a crucial factor in enabling communication networks all around the globe. The utility of satellites for communication has grown manifold over the past years. The design of a satellite communication system is a complex procedure requiring trade-offs between many factors to achieve the best performance at an acceptable cost. Both, excessive and low margin are undesirable which results in a lot of constraint on the electronic system. In satellite communication, transmitter and receiver are the two systems responsible for commanding and ranging. The analog receiver block used has the potential to have lot of variations due to multiple sources and same is true for the transmitter block. Modern day terrestrial and satellite communication systems demand optimization of each sub-system to achieve the desired specification. In the present world, GEO satellites carry the vast majority of the world's satellite traffic, therefore it becomes of utmost importance to design the link budget with an optimum utilization of the space segment as well as feasibility of transmission of signals over long distances. Though a continuous and a reliable communication link is strongly recommended for all spacecraft operations such as payload data transmission, TT&C signal transmission and reception for all classes of spacecrafts, the accountability of the communication links is very critical during implementation for interplanetary missions or human space missions. This article demonstrates the simulated performance of each block and the performance of the cascaded chain of both transmitter and receiver using System simulation software. Simulated performance of each block provides an opportunity to predict and optimize the performance of each individual block. Further the link budget is calculated and the worst-case analysis is detailed in this article.

This article details the indigenous development of CFRP based carrier plates for possible replacement of standard Kovar based carrier plates employed in front-end RF circuits at microwave frequencies. The development encompasses fabrication of CFRP based carrier plates, plating of the assembly, temperature trials, attachment and assembly of the substrates along with the RF characterization. The front-end of RF circuits consists amplifier, filter which are realized on alumina substrate. The assembly is attached to the developed gold plated CFRP carrier plates. The resulting structure achieved six times weight reduction compared to standard topology without any performance degradation. The development encompasses process details, comparative analysis, various trials along with performance characterization.

The main bottleneck faced by the industry and public sector is the adoption of outdated technology and stagnant approach leading to inefficient system. In Indian scenario this gap is evident more due to self-cantered approach and easy going attitude. Moreover mushrooming colleges and lack of application oriented approach leads to situation where researchers are more concerned of their completion on paper rather than practical implementation of the same thereby creating a situation for technological adavancement taking back seat. Various models are in place to bridge the gap and are at par with the prevailing world standards but attitude and lack of application oriented approach has led to situation of not achieving desired results. Further the quick turnaround requirement of industry in cost effective manner is also hampering the effective coordination between the two important pillars of the nation. This article will dwell upon the present scenario, analysis of the causes with suggestive methodology for yielding better outcome in Indian scenario.

Gender classification and emotion detection plays an important role in the areas security. Gender classification and emotion detection aids in identification of a person by recognizing its gender (male/female) with their emotions (happy/sad) from the face image only. Individual works has been done in the Gender classification and emotion detection fields but not together. In this paper, we proposed a system to do detection of emotion and gender simultaneously for a specific face image. In this paper AIGLBP (Approximation image Gabor local binary pattern) is applied for feature extraction and SVM is used for classification. The number of experiments is initiated on a standard face image databases taken in controlled (FERET and INDIAN FACE) environment. The experimental results demonstrate that the proposed system is effective enough to give high performance in terms of speed and accuracy.

In this paper, we present the objectives and features of the payload subsystem of SNSAT, the nanosatellite which is to be launched by SathyabamaUniversity in near future. The payload comprises of the spectrometer and its interface, with the prime aim to detect the concentration of five major constitutes green house gases namely, Carbon Dioxide, Water, Carbon Monoxide, Methane and Hydrogen Fluoride whose wavelength range between 900nm and 2.5μm (near infrared band). It records infrared radiation emitted from the Earth's surface. By absorption spectrometry, absorption and the column density of these gases can be obtained. Linear Indium Gallium Arsenide (InGaAs) photodiode detector array is employed. The array is hybrid InGaAs and CMOS active-pixel readout electronics. Detector has Spectral Resolution is approximately 6 nm. Optics employs 35 mm optics to collimate radiation from a 1 km tile onto a diffraction grating and then focus it onto the detector array. Data packets are processed and transmitted to the OBC subsystem using either RS232 interface or TLL logic at a period of 100ms. The payload is designed to consume less than 1 watts of power.