It is known that the surface of Mars is covered with regolith. There have been a few missions operating on Martian surface to study the various physical quantities of interest. The Martian regolith has large amount of iron content. Though some measurements of iron content in the regolith exist in literature, it would be interesting to carry out in-situ measurement of the same by future lander or rover mission. Hematite is an iron oxide and is very important to study the climatic evolution of Mars. In order to carry out investigation like measurement of hematite mixed with regolith, a compact wireless sensor is designed, capable of measuring the electrical properties of the soil. In this paper, we have presented its design aspects, results of terrestrial soil and Martian soil simulant. We have selected Mojave Mars Simulant (MMS) as the analogue material for testing. The results are validated using distilled water, whose properties are known. The sensor works in the frequency domain with capability to sweep the frequency in a given measurement range and measures the soil impedance. From the given algorithm, the electrical and magnetic properties of the soil are derived. The results are useful to understand the hygroscopic characteristics of Marian soil or to obtain the iron content mixed with the regolith by the sensor after upgrading in space-worthy version.

In silicon diaphragm fabrication, smooth walls and bottom formation has been a difficult task during micromachining of (100) silicon due to its orientation-dependent chemical etching. The intended method has been developed in order to realize the perfect diaphragm together with the tunnel using anisotropic etching technique for the fabrication of MEMS-based silicon bulk micromachined acoustic sensor. Due to the restriction of the undercutting process, the wet anisotropic approach offers only limited patterns of silicon diaphragm. Smooth walls and bottom of about 470 �m deep silicon microstructures have been obtained after controlling the etchant composition, temperature and orientation of the masking pattern. LOCOS technique is used to obtain the desired structure. The paper reports the successful method of fabrication of the structure and different complex shapes that may develop during the wet anisotropic etching of the silicon bulk.

The paper presents the outage probability and the Average Bit Error Rate (ABER) for a Multiple-Input Multiple-Output (MIMO) system over generalized-fading channel. Transmit antenna selection at the base station is performed and Maximal Ratio Combining (MRC) at the receiver is considered for the downlink transmission. The antenna at the transmit end that maximizes the instantaneous output Signal-to-Noise Ratio (SNR) is selected for transmission. The effect of fading parameters on the performance of the system has been observed analytically. The effect of the number of transmit and receive antennas on the system has been studied. Computer simulations are performed to assess the accuracy of the proposed mathematical analysis.

Recent developments in materials technology are driving the field of photovoltaic (PV) devices, especially, graphene that exhibits outstanding electronic and photonic properties. The focus here is on the incorporation of graphene layer in silicon solar cells. The optimization of the proposed structure is carried out by studying different technological and geometrical parameters such as thickness of graphene layer and its positioning in the silicon solar cells using RSoftCAD software and fullwave simulator. Graphene as hole transportation layer offers maximum power conversion efficiency of ~26%.