Rajesh Kumar Vishwakarma

Electromagnetically Coupled Square Microstrip Antenna for Dual-Band Operation

In this paper a stacked square microstrip antenna for dual-band operation is presented. The patch is stacked by electromagnetic coupling between the parasitic patch (Upper patch) and driven patch (Lower patch). The stacked microstrip antenna is a particular characteristic such as a high gain or a wide band width and dual band. When the size of parasitic patch is nearly equal to the fed patch and the distance between the feed patch and the parasitic patch is approximately 0.1mm wave length, the band width is increased. For obtaining dual-band the variation of dimension (2.0 mm) in the square patch has been done. This antenna works well as dual-band in the frequency range (2.69-3.41 GHz). The dual-band achieved by variation of stacked square patch dimensions between upper patch antenna and lower patch. The obtain ration of resonance frequencies are increases from 1.25 to 1.32 with increasing the dimensions of stacked square patch antenna. The input impedance and VSWR return loss have been measured with the help of Network analyzer.

Aperture Coupled Microstrip Antenna for Dual-Band

This paper presents air gap aperture coupled microstrip antenna for dual-band operation over the frequency range of (2.9 to 6.0 GHz). This antenna differs from any other microstrip antenna with their feeding structure of the radiating patch element. Input signal couples to the radiating patch trough the aperture that exists on the ground plane of microstrip feed line. The dual-band achieved by variation of air gap [2 mm to 6 mm] between single patch antenna and aper-ture coupled microstrip antenna. The main advantage of this type antenna is increased the bandwidth of the antenna as compared to a single layered patch antenna. The two resonant frequencies can vary over a wide frequency range and the input impedance is easily matched for both frequencies. The obtain ratios of resonance frequencies are variable from 2.1 GHz to 1.1 GHz with increasing the air gap between single patch and aperture coupled microstrip antenna. The measured return loss [–14 dB] exhibits an impedance bandwidth of 35%. The input impedance and VSWR return loss have been measured with the help of Network analyzer.

Microstrip antenna with swastik slot for UWB applications

In this paper first we design a swastik slot loaded rectangular microstrip antenna fed by a microstrip line (50 Ω) and then analyze its performance. It consists of a rectangular patch with swastik-shaped slot on one side of the substrate (30*30*1.6 mm3) and partial ground plane (16*8 mm2) on the other side. Here, we use FR-4 epoxy substrate. The proposed antenna is designed by using HFSS simulation tool. This antenna design gives impedance bandwidth of 10.5 GHz operating over a frequency range of 4.1 to 14.6 GHz with VSWR <; 2. These characteristics make the designed antenna suitable for various UWB applications.

L-shaped Microstrip Antenna for Wideband

In this paper, analysis of double L-slot loaded patch antenna is presented. The antenna can be designed for applicable in C-band space communication system. The proposed antenna provide much improved bandwidth (6 %). The 3dB bandwidth of the antenna is found to be 410 MHz for the central frequency of 6.9 GHz. The theoretical results obtained from the analysis are compared with IE3D simulated and experimental results which are in good agreement.

Rectangular notch microstrip antenna for dual-band operation

Microstrip antenna consists of a radiating patch on one side of dielectric substrate which has a ground plane on the other side. The antenna element it self may be square, rectangular, circular, triangular etc and may have more than one feed. An experimental study of dual band characteristics of single layer rectangular microstrip antenna is presented. For feeding of the antenna direct microstrip coupling with proper matching transformer has been used. The optimized notch dimension has been taken for two resonant frequencies. The resonance frequency changes with the variation in the length and width of the notch. The VSWR is measured with the help of network analyzer.

A Circular Disc Microstrip Antenna with Dual Notch Band for GSM/Bluetooth and Extended UWB Applications

A microstrip antenna with a circular disc design and modified ground is proposed in this paper. Circular shapes of different size have been slotted out from the radiating patch for achieving extended ultra wideband (UWB) with GSM/Bluetooth bands with maximum bandwidth of 17.7 GHz (0.88-18.6 GHz). Further, characteristic of dual notch band is achieved, when a combination of T and L-shaped slots are etched into the circular disc and ground plane respectively. Change in length of slots is controlling the notch band characteristics. The proposed antenna has rejection bandwidth of 1.3-2.2 GHz (LTE band), 3.2-3.9 GHz (WiMAX band) and 5.2-6.1 GHz (WLAN band) respectively. It covers the frequency range of 0.88-18.5 GHz with the VSWR of less than 2. Also, an equivalent parallel resonant circuit has been demonstrated for band notched frequencies of the designed antenna. The gain achieved by the proposed antenna is 6.27 dBi. This antenna has been designed, investigated and fabricated for GSM, Bluetooth, UWB, X and Ku band applications. The stable gain including H & E-plane radiation pattern with good directivity and omnidirectional behavior is achieved by the proposed antenna. Measured bandwidths are 0.5 GHz, 0.8 GHz, 1.1 GHz and 11.7 GHz respectively.

Microstrip fed highly compact Bluetooth integrated wideband antenna for wireless application

ABSTRACT In this paper, a compact microstrip fed UWB monopole antenna for dual band applications is proposed and investigated. The base of the proposed antenna is a rectangular shaped radiator. The radiator of an antenna occupies a small area of only 10.2 × 7.6 mm2 (0.081λ0 × 0.06λ0) that covers the UWB frequency range. To create a dual band antenna by etching a quarter wavelength resonator, loop strips into radiator is designed which generates the notch band characteristic. The proposed structure consists of rectangular patch shape at centre with two symmetrical loop strips. Dual band antenna is designed on FR-4 substrate whose dielectric constant is 4.4, tangent loss 0.02 and thickness 1.59 mm. The overall size of proposed antenna is 15 mm × 15 mm (0.12λ0 × 0.12λ0). The 10-dB impedance bandwidth of the antenna is 520 MHz (2.3–2.82 GHz) and 5.51 GHz (3.8–9.31 GHz). Also same configuration antenna is designed on Roger RT/Duroid substrate whose dielectric constant is 2.2, loss tangent 0.0009 and thickness 30 mil (0.762 mm). The simulated result is approximately same as FR-4. It covers the LTE, ISM, WLAN, WiMAX, X band satellite communication and ITU bands for wireless communications. To verify the proposed antenna design and response, a prototype has been fabricated on FR-4 and parameters are measured. The measured response validates the simulated response.

Microstrip Antenna with Defected Ground Structure (DGS) for Multiband Operation

In this paper, a microstrip feeding rectangular MPA using DGS structure into ground plane is presented. In the absence of a slot, a conventional rectangular MPA is also considered for confirming the validity of designed antenna. This conventional antenna design was found to resonate on 7.0611 GHz frequency at −23.70 dB return loss. When introducing the combination of two L-shaped DGS structures into the ground plane, then the frequency shift from 7.0611 GHz to 3.2012 GHz is observed. The main involvement of this antenna design is the multiband responses. Further, the end result confirms that the designed DGS antenna has return loss at −14.0170 dB on 3.2012 GHz, −16.5623 dB on 4.4505 GHz, −17.8874 dB on 5.1952 GHz, and−17.5474 dB on 8.9349 GHz.

A stacked microstrip antenna for multiband applications

A stacked microstrip antenna with H-shaped parasitic patch for multiband applications is presented in this paper. The antenna designing is done by using HFSS simulation tool and feeding by microstrip feed line (50Ω). In the absence of slot a conventional rectangular microstrip patch antenna is also considered for confirming the validity of designed antenna. This conventional antenna design found to resonant at 7.0611 GHz frequency with a return loss of -23.70 dB. When introducing rectangular patch stacked with H-shaped patch, then the frequency shift of 7.0611 GHz to 4.0563 GHz is observed. The major involvement of this design antenna is the multiband responses. Further, the end result confirms that the designed antenna has the return loss of -25.3489 dB at 4.0563 GHz and -18.7150 dB at 4.6059 GHz and -13.5745 dB at 5.9527 GHz and - 25.2464 dB at 7.7920 GHz.

Design of Dual Band Slot Loaded Rectangular Microstrip Antenna for Global Positioning Satellite

This paper presents an experimental investigation of inclined slot loaded rectangular micro strip antenna that has been carried out for dual -band operation with the help of a single probe feed for Global Positioning Satellite (GPS) applications. In this case, two resonant frequencies 1.57 GHz and 1.22 GHZ occur. It is observed that the VSWR and RETURN LOSS of two resonant frequencies can be changes by inclination angle of the slot. The design of this antenna is being simulated in IE3D software.