Ganga Prasad Pandey

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.

Reconfigurable circularly polarized capacitive coupled microstrip antenna

The design and measurement of reconfigurable circularly polarized capacitive fed microstrip antenna are presented. Small isosceles right angle triangular sections are removed from diagonally opposite corners for the generation of circular polarization (CP) of axial ratio bandwidth of 11.1%. Horizontal slits of different lengths are inserted at the edges of the truncated patch to provide the dual-band CP and by switching PIN diodes across the slits ON and OFF, reconfigurable circularly polarized antenna is realized. The antenna shows dual-band behavior with reconfigurable CP. In order to enhance the operation bandwidth of the antenna, an inclined slot was embedded on the patch along with PIN diodes across the horizontal slits. This proposed antenna gave an impedance bandwidth of 66.61% (ON state) ranging from 4.42 to 8.80 GHz and 68.42% (OFF state) ranging from 4.12 to 8.91 GHz and exhibits dual-frequency CP with PIN diode in OFF state and single-frequency CP with PIN diode in ON state with good axial ratio bandwidth. The axial ratio bandwidth of 4.42, 2.35, and 2.72% is obtained from the antenna. The antenna has a similar radiation pattern in all the three different CP bands and almost constant gain within the bands of CP operation.

Multiband Circularly Polarized Stacked Microstrip Antenna

In this paper, a multiband circularly polarized capacitive coupled stacked microstrip antenna is proposed. The multiband circular polarization (CP) is achieved by corner truncation, embedding slits and inclined slots on a three layered antenna structure. The proposed antenna also shows wideband behavior with an impedance bandwidth of 52.13% in the frequency range of 4.85 GHz to 8.27 GHz, while 3 dB axial ratio bandwidths in five CP bands are 0.51%, 4.54%, 0.33%, 0.83% and 1.29% in the frequency range of 5.12 GHz to 5.15 GHz, 5.45 GHz to 5.70 GHz, 5.90 GHz to 5.92 GHz, 6.25 GHz to 6.31 GHz and 7.68 GHz to 7.78 GHz, respectively. The antenna prototype is fabricated, and simulated results as axial ratio, radiation pattern and the reflection coefficient are validated with measured result.

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.

A Novel Ultra-Wide Band Magneto-Electric Dipole Antenna with Cavity Reflector

A magneto-electric dipole antenna with novel feed design with rectangular cavity is proposed, fabricated and analyzed. Due to this new feeding structure, the antenna has been able to achieve wide impedance bandwidth of 68.8% to accommodate various wireless communication applications. The stable peak gain of 10.45 dBi with unidirectional radiation pattern has also been reported for the entire range of operation. The antenna has also been able to achieve low cross polarization levels lower than −30 dB. The antenna exhibits low side lobe radiations and almost identical E plane and H plane radiation patterns in the operating frequency range of 2.0 GHz–4.1 GHz. Due to its good electrical characteristics, the antenna is suitable for various S-band wireless communication applications.

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.

Fractal Based Triple Band High Gain Monopole Antenna

Abstract A novel triple-band microstrip fed planar monopole antenna is proposed and investigated. A fractal antenna is created by iterating a narrow pulse (NP) generator model at upper side of modified ground plane, which has a rhombic patch, for enhancing the bandwidth and gain. Three iterations are carried out to study the effects of fractal geometry on the antenna performance. The proposed antenna can operate over three frequency ranges viz, 3.34–4.8 GHz, 5.5–10.6 GHz and 13–14.96 GHz suitable for WLAN 5.2/5.8 GHz, WiMAX 3.5/5.5 GHz and X band applications respectively. Simulated and measured results are in good agreements with each others. Results show that antenna provides wide/ultra wide bandwidths, monopole like radiation patterns and very high antenna gains over the operating frequency bands.

A new wideband end-fire Magneto-Electric dipole antenna

In this paper, an end-fire antenna has been designed for forward and rear vision in airborne radar applications. The purpose of this work is to demonstrate the feasibility of end-fire Magneto-Electric dipole antenna with good bandwidth, stable gain and low cross polarization. A new kind of end-fire Magneto-Electric dipole antenna, composed of a planar electric dipole and a shorted patch has been designed and fabricated. Being different from conventional broadside Magneto-Electric dipole antenna, this antenna has been excited by Z shaped feed line to impart end-fire radiation pattern. A wide impedance bandwidth of 23.9%, with 8.5dBi peak gain and 8.7dBi peak directivity has been achieved for the frequency range 12.2GHz–15.5GHz. Antenna efficiency of 90% and low cross polarization level for entire range of operation has also been observed. The antenna also exhibits low side lobe radiations and almost identical E plane and H plane radiation patterns in the given frequency range. The antenna has a wide potential for various airborne applications in Ku band.

A Novel Magneto-Electric Monopole Antenna for C Band Wireless Applications

A new design of non-planar magneto-electric monopole antenna is proposed and presented. This antenna consists of a novel design of electric monopole with dual shaped feed line design and possesses 61.5% impedance bandwidth, from 4.5 GHz–8.5 GHz. The antenna exhibits stable omnidirectional radiation pattern with almost identical E-plane and H-plane radiation patterns and also provides a peak gain of 7.4 dBi. Due to its good electrical characteristics and radiation parameters, the antenna has great capability to operate in C band, to overcome the challenges of multi-frequency applications.

Design of Circularly Polarized Planar Magneto-Electric Dipole Antenna

A new design of a circularly polarized planar magneto-electric dipole antenna is proposed and presented. This antenna consists of dual horizontal T-shaped electric dipole and an inverted U- shaped feed line. The antenna possesses 21.1% impedance bandwidth, from 8.9 GHz-11.0 GHz, provides 3-dB axial ratio bandwidth of 9.52% ranging 10.0 GHz-11.0 GHz, exhibits stable omnidirectional radiation pattern with almost equal E-plane and H-plane radiation patterns and provides a peak gain of 6.2 dBi. Due to its good electrical characteristics and radiation parameters, the antenna is suitable for satellite and RADAR communication in X-band.