R. M. Vani

Slot-loaded Rectangular Microstrip Antenna with Meandering Slots in the Ground Plane for Compact Broadband Dual-frequency Operation

In this paper, a novel compact broadband dual frequency microstrip antenna is presented. The proposed design consists of a rectangular microstrip antenna with a pair of parallel slots loaded close to the radiating edge of the patch and three meandering narrow slots embedded in the antennas groundplane. Experimental study was carried out by varying the length of the meandering slot. Using three meandering slots in the groundplane a significant lowering of the both resonant frequencies is obtained with an enhanced operational bandwidth in comparison to standard rectangular microstrip antenna without slots. An increase in the bandwidth is more significant for lower resonant frequency. With the proposed design a size reduction of 50.6% and 30% for the two resonant frequencies is obtained with the measured bandwidths of 12.2% and 4.5% respectively. The two frequencies have an operation frequency ratio of 1.40.

Wideband gap-coupled suspended rectangular microstrip antenna

In this paper, we present the bandwidth enhancement of microstrip antenna using microstripline feed, suspended and gap-coupled configuration. First, the bandwidth of suspended microstrip antenna (SRMSA) is enhanced by gap coupling the parasitic patch to the radiating edge of fed patch of the antenna. Using this technique, an optimum bandwidth of 22.24% is obtained. Later, two parasitic patches are gap-coupled to the non-radiating edges of fed patch of SRMSA. This enhances the bandwidth of antenna and a maximum bandwidth of 53.25% is obtained. The air gap is kept same in both cases. The enhancement of impedance bandwidth is achieved without affecting the nature of broadside radiation characteristics. The proposed antenna may find applications in radar communications. Design concept of the proposed antennas is described and their experimental results are discussed.

Novel design of microstrip leaky-wave antenna array for dual beam operation

This paper presents the design and development of two, three and four elements series fed microstrip leaky-wave antenna (MLWA) for dual beam operation for 60deg skewing angle between the beams. The proposed technique consists of slot used between the array elements, which eliminates active phase shifter to achieve beam skewing. If the array elements are increased from two to four in MLWA the power level of the main beam decreases from -4.40 dB to -5.57 dB without changing the skewing angle. The simulation results obtained using HFSS v9.2 simulation software is verified experimentally which are in good agreement with each other.

Design and Development of Integrated Inclined Slot Waveguide Antennas

Single and dual integrated inclined slot waveguide antenna designed on a Rogers RT/duroid 5880 [tm] microwave substrate is presented. The impedance bandwidth and radiation pattern of integrated inclined single slot waveguide antenna (IISSWGA) and integrated inclined dual slot waveguide antenna (IIDSWGA) are described. The obtained impedance bandwidth and radiation pattern are quite good. These wide band and broad side radiation patterns may find applications in various radar communication systems.

Opposite‐Phased V‐slot Array Located on the Narrowwall of the Rectangular Waveguide Antenna with Flange Technique

In this study we present the opposite‐phased V‐slot array located on the narrowwall of the rectangular waveguide antenna (V‐SANWRWGA) with flange technique. The designed antenna consists of 3‐pairs of symmetric, opposite‐phase V‐slots grooved on the narrowwall of the rectangular waveguide. Further, the metallic flanges are specially designed and machined which can be easily fixed to the V‐SANWRWGA with help of hinges. The characteristics like radiation pattern, beam width and gain are measured experimentally for the different flange angles. The experimental radiation pattern is explained on the basis of Moullin’s theory. The theoretical and experimental results are found to be in good agreement. Details of antenna design are described and experimental results are discussed.

Effect of U‐Slot Length Variations on the Performance of Stacked Microstrip Antenna

Antenna miniaturization plays an important role in the design of modern personal wireless systems. Several minimization techniques have been known for a long time. The mail minimization tools are loading the antenna with lumped elements, high permittivity dielectric materials or conducting additions; using a ground plane with short circuits and optimizing the geometry. In this paper, a compact stacked microstrip antenna with loaded U‐slot on the driven (lower) patch and probe feed structure is proposed. The purpose of this paper is to study the variations of a U‐slot length with the parameters of stacked microstrip antenna such as input impedance, bandwidth and resonant frequency etc. The paper emphasizes the significant change observed in the performance of compact stacked microstrip antenna. Earlier work has utilized a U‐slot on the planar microstrip antenna and the effect of slot width on performance of microstrip antenna is studied. The software package IE3D® version 11.5 was used to simulate the ante...

Study of longitudinal patch array antenna

The longitudinal patch array antenna (LPAA) and longitudinal complimentary array antenna (LCAA) are designed and fabricated for a resonant frequency of 9.6 GHz. The various antenna parameters are measured experimentally. The experimental study reveals that the LPAA and LCAA are almost the same as that of the conventional longitudinal slotted waveguide array antenna (LSWAA). The comparative study between LPAA and LCAA reveals that LCAA is slightly better than LPAA. The LPAA and LCAA are found to be light in weight, easy to fabricate and cheaper than the LSWAA.