L-Slots Square Antenna for Octa-band Applications

The objective of this paper is to design an Octa- Band L-slot Square Patch antenna which will operate in 3.18 GHz, 4.71 GHz, 7.04 GHz, 8.38 GHz, 8.86 GHz, 10.66 GHz, 11.76 GHz, 14.12 GHz frequencies. The same antenna would also work in UWB frequencies. An L-slots Square copper patch with a thickness 0.035mm is placed on FR4 epoxy substrate having dielectric constant 4.4 with a height of 1.6 mm with single port. This has been designed using HFSS commercial software simulator so that Return Loss, VSWR, Radiation pattern and Surface current distribution can be measured.

An electrically switchable wideband metamaterial absorber based on graphene at P band

Graphene has the capability of dynamically tuning its conductivity through gate voltage. Based on this fact, an electrically switchable wideband metamaterial absorber at low frequencies is presented and investigated in this paper. Our calculated results show that its absorption is over 90% from 400 to 1,000 MHz with the Fermi level of graphene being at 0 eV and the absorption band can be switched by adjusting the Fermi level of graphene without changing its physical structure. Moreover, the surface current distribution enables us to reveal the switchable wideband absorption characteristics of our designed metamaterial absorber. At last, we prove that its absorption property is polarization-insensitive due to the rotational symmetry of the structural unit. This work may provide a further step in the development of switchable sensors and absorbers at low frequencies.

Multiple element of miniaturized printed log-periodic second series koch dipole array antenna for wideband chipless RFID tag reader

This paper aims to produce a low profile, wideband, and high gain antenna for chipless RFID tag readers. A miniaturized and wideband printed Log-Periodic Second Series Koch Dipole Array (LPSSKDA) with eleven elements operating over 0.8 GHz-3.2 GHz is designed using the FR4 board. The single LPSSKDA antenna, which acts as the chipless RFID reader antenna having gain between 5.2 and 6.1 dBi and frequency range from 1-3 GHz. A double element of the LPSSKDA antenna is proposed for improving the antenna gain to 6.9-7.9 dBi over the frequency range. The antenna is fabricated to validate the simulation and measurement results in terms of reflection coefficient, radiation pattern, and surface current distribution.

Frequency Reconfigurable Compact Antenna for Multiband Wireless Communication Application

This pioneering work suggests a reconfigurable multiband frequency antenna for applications in wireless networking The miniaturization and multi-band function of the mounted antenna is done by inserting a rectangular hole, and the reconfiguration of the frequency is achieved by utilizing two PIN diode switches. The ON and OFF state of the PIN diode determines the surface current distribution of the radiating patch resulting in the multiband resonance and reconfiguration of the proposed device. Application and analysis dependent on parameter of the antenna such as lack of return loss, VSWR, gain, and radiation pattern. The developed antenna is used for the intended application of wireless communication. Simulation is performed using Ansys HFSS.

A Compact Wide Bandpass Filter for Satellite Communications with Improved Out-of-Band Rejection

This paper presents a compact C-band bandpass filter with improved out-of-band rejection. It consists of a symmetric three-pole parallel coupled line microstrip loaded with complementary split ring resonators (CSRRs) and slot resonators. Enhancements regarding the filter responses are obtained by etching these two parasitic shapes successively. When, CSRRs are introduced in the ground plane, exactly in the back of the transmission line of 50 -Ohms , improvements on the filter selectivity level are achieved. Whereas, the slot resonator elements are implemented on the feed line to permit the suppression of the second harmonics. To reduce the second harmonics of 11:1-13GHz, the parasitic elements are both combined, widen the filter rejection of 5:81%. The surface current distribution together with the equivalent circuit are also studied in order to demonstrate the slots and the CSRRs effect parameters on the behavior of the proposed filter. A prototype of the optimal filter is fabricated and measured.Theory and experiment results prove the validity of the new design procedure.

High Gain V-Antenna Array for 60 GHz WiGig Network

: This paper provides an efficient but simple designed V-Shaped microstrip array antenna on a RT duroid substrate of dimension 50 mm× 40 mm × 1.6 mm . By considering the ratio of the length of one leg of the V-element and wavelength of the desired frequency , the angle between two legs of V-Patch has been determined . For a more efficient outcomes , an array design of 4-elements is made and its comparison with single element is done .A simple line feed technique has been used , with feedline width of 3mm .The proposed structure is simulated by using Ansys HFSS software and S-Parameter , antenna gain , directivity, Standing wave ratio and surface current distribution have been determined .Unlike conventional patches, the array contains a separation between two consecutive V-Elements in the shape of a rectangular patch termed as element separation band (ESB ) and it plays an important role in modifying the antenna gain and directivity. This antenna produces a return loss of -39.387 dB at 60.58 GHz frequency to cater the present demand of 60 GHz Wi-Gig and WPAN.

Magneto Dielectric-Laden Miniaturized Wideband Meander Line Antenna for Mobile Devices

This research presents a miniaturized wideband meander line antenna (MLA) using a magneto dielectric (MD) material for mobile device applications. The proposed MLA attached the lower and upper ground planes of the folder-type chassis, connected electrically by grounding strip. The MD material (ECCOSORB MF-124) was subsequently loaded onto the coupling element area of the MLA. The MD-laden MLA was ultracompact (10 mm × 25 mm × 1 mm), with the electrical size of 0.015λ × 0.039λ × 0.0015λ at 470 MHz. The surface current distribution was simulated to determine the optimal parameters of the MD-laden MLA. To verify, a prototype antenna was fabricated and the experiments were performed. The measured impedance bandwidth (S11<−6 dB) covered the frequency range of 467–1012 MHz (73.6%), with an omnidirectional radiation pattern. The radiation efficiency was in excess of 90%, rendering it suitable for the DVB-H/LTE13/GSM850/900 applications.