Surendra K. Gupta

Double MOS loaded circular microstrip antenna for frequency agile

A new MOS integrated frequency agile circular microstrip antenna is analyzed and designed using modal expansion cavity model and circuit theoretic approach. The various parameters are electronically controlled by changing the bias voltage of MOS. The maximum frequency agility for double MOS loaded antenna was 3.4888GHz (66.29%). The antenna gain range is found to be 1 to 3.14 for bias voltage from 0–5 V. The simulated and calculated results for VSWR of double MOS integrated antenna show close resemblance.

Analysis of tunnel diode loaded H-shaped microstrip antenna

In this paper, a compact H-shaped microstrip antenna loaded with tunnel diode is proposed and investigated theoretically. The H-shaped patch is investigated, and it has been concluded that a notch dimension of 8 mm by 6 mm gives best results. Then, the tunnel diode is loaded, which provides tunability to the microstrip antenna. The numerical results for input impedance, return loss, resonant frequency and radiation pattern are presented and compared with simulated results. The radiation pattern is varied from 63.8° to 60.6° with bias voltage, and a frequency agility of 25.28% has been achieved.

Compact Multiband Slit Cut Circular Patch Antenna over SRR Based Metamaterial Substrate with Shorting Posts

This paper presents a novel, highly compact, and multiband circular patch antenna. The paper includes the analytical study on the meandered circular patch antenna and single unit cell of a Split Ring Resonator based metamaterial substrate for the multiband operations and further lowering of resonant frequencies obtained with shorting posts observed from the return loss curve. Circuit model of SRR configuration is also presented. Effects of complementary SRR slot on the ground plane are parametrically studied. Proposed configuration with huge amount of compactness of around 48% covers two bands of microwave regime around 4-12 GHz i.e. in C and X-bands and thus applications pertaining to this regime are also discussed.

Analysis of Superstrate Loaded Slit Cut Circular Patch Antenna for Triple Band Operations

This paper presents a novel slit cut circular patch antenna (SC-CPA) with supers rate. An analysis of triple band slit cut circular patch antenna with supers rate is presented and results are verified by simulation. Various parameters of antenna such as input impedance, return loss and gain are investigated. The parametric study of frequency response of antenna is carried out for different heights of dielectric supers rate or cover causing the lowering of the resonant frequencies. The proposed antenna possessing triple band characteristics and resonates at 7.2 GHz, 8.5 GHz, and 10 GHz. Antenna possess a peak gain of 2.15 dB with a compactness level of around 20%. Antenna is investigated to provide protection from environmental hazards and it is worth for triple band operations.

Analysis and design of L-strip proximity coupled circular microstrip antenna

An L-strip proximity coupled circular microstrip antenna is proposed. The structure is investigated using circuit theoretic approach and simulated using IE3D simulation software. The patch is designed on a thick substrate of thickness of 11 mm for a design frequency of 3.74 GHz and provides ultra wide band operation. The numerical results for input impedance, VSWR, radiation pattern, efficiency and gain are presented. Bandwidth is found to be dependent on length of horizontal part of L-strip. A bandwidth of 69.52% is achieved (for VSWR<2) for y0=0.112λ0 and h2=0.097λ0. The beam of antenna rotates with operating frequency.