This issue is a special issue consisting of seven research papers presented at the National Conference on Advances in Microelectronics, Instrumentation and Communication (MICOM-2015) held at BITS Pilani, Pilani Campus, Rajasthan during November 20-22, 2015. This conference focused on the evolving technologies and advancements made in the areas of Microelectronics, Instrumentation and Communication. Most of the selected papers are based on microwave antenna design and related fields.

Communication antenna has become an essential component of wireless telecommunication technology either through a broadcasting or via a personalized device. Usually, the theoretical understanding of antenna needs to determine the distribution of current on the surface of the used metallic structure to predict the input impedance, radiation pattern and directional properties. The successful utility of dipole antenna in wireless communication during the Second World War was based on its reliable theoretical results, and today it has diversified applications in radio navigation, satellite communication, microwave and millimeter wave communication, cellular and personal communication and many more.

The first paper, “Differentially-Fed Half-Cylindrical Dielectric Resonator Antenna for Dual-Mode Applications“, by A V Praveen Kumar, reports differentially-fed half-cylindrical dielectric resonator antenna design to excite two different modes at the proper phase difference between the two feed lines. The paper presents a minor design change to make the operation of DRA either in single mode or in a dual mode.

Dielectric Resonator Antennas (DRAs) perform better at microwave frequencies due to its well defined far-field patterns. The second paper, “Parasitic Metal Loading to Purify the Higher-Order Mode of a Cylindrical Dielectric Resonator Antenna“, by A V Praveen Kumar, reports that the placement of metallic strip at certain planes of a Cylindrical Dielectric Resonator Antenna (CDRA) improves the purity of the co-polarized fields of its Higher Order Mode (HOM). The metallic boundary also suppresses the spurious field components of the HOM, which are responsible for a distorted radiation pattern.

Electromagnetic microwave absorber is one of the major applications of metamaterials to obtain high absorption through resistive and dielectric loss. This absorber can be made ultrathin and highly absorptive to a range of frequencies from microwave to optical wave. The authors, Chandrakant R Rana, Kirti Inamdar and A H Lalluwadia in their paper, “Study, Design and Analysis of U-Shaped Metamaterial Absorber for X-Band Application“, report the development and working of a novel ultra-wide band, ultrathin metamaterial absorber. The proposed structure is based on simple U-shaped metamaterial printed on a metal-backed dielectric substrate.

The fourth paper, “Bandwidth Enhancement Using Stacked Configuration in Microstrip Antenna Array for Millimeter Wave Applications”, by Soni Goel, Ashmita Kamal and Priyanka Choudhary, presents an array of 2 x 2 microstrip antennas utilizing thin substrate of RT Duroid 5880 with a permittivity er = 2.2. The basic design of 2 x 2 array antenna utilizing RT Duroid is extended for two superstrate loaded antennae designs. The first design uses foam and the other design uses RT Duroid with air gap as superstrates. 2 x 2 array patch engraved on RT Duroid above ground plane acts as driven patch, while the patch incised upon the superstrate acts as a parasitic patch. The paper reports an optimized design to achieve the highest gain in millimeter wave region maintaining a wider bandwidth.

The fifth paper, “An Eco-Design of Dielectric Resonator Antenna for Wideband Applications“, by Jitendra Kumar and Navneet Gupta, reports a Dielectric Resonator Antenna (DRA) design taking the environment parameters into consideration. The design proposes lesser material and energy to reduce the environmental impact claiming nearly 52% consumed material as compared to conventional rectangular DRA working on the similar operating frequency.

The last paper, “Face Recognition Technology: A Review”, by Jagdish Chandra Joshi and K K Gupta, is a review paper reporting a survey on face recognition techniques related to the area of biometrics, pattern recognition and computer vision. The paper discusses various well-established algorithms used in face recognition to enhance its utilization manifold over other conventional biometric methods.

--V K Chaubey
Consulting Editor