Microstrip band-stop filter based on double negative metamaterial

In this work, we present a novel miniature band stop filter based on double negative metamaterial, this circuit is designed on a low-cost substrate FR-4 of relative permittivity 4.4 and low tangential losses 0.002. The proposed filter has a compact and miniature size of 15 mm in length and 12mm in width without the 50 Ω feed lines. The resonator was studied and analyzed with a view to achieving a band-stop behavior around its resonant frequency. The band-stop characteristics are obtained by implementing the metamaterial resonator on the final structure. The obtained results show that this microstrip filter achieves fractional bandwidth of 40% at 2 GHz. Furthermore, excellent transmission quality and good attenuation are achieved. This filter is an adequate solution for global system for mobile communications (GSM)

A new design of UHF tag antenna for clothing identification using SRR

In this paper, we present a new antenna for radio frequency identification (RFID) tag operating in the Moroccan ultra high frequency (UHF) band around 868 MHz, this antenna is designed on a flexible plastic substrate of relative permittivity 3 and low tangential losses which is 0.002. The proposed tag is designed to identify clothing in supermarkets. The tag antenna has a miniature size of 38 mm in length and 26 mm in width. This miniature size was obtained by using two rectangular split ring resonator (RSRR). The impedance matching of the RFID chip with the antenna was carried out by a double T-matching structure. The antenna is designed, simulated and optimized using computer simulation technology (CST) microwave studio software and good results have been obtained in terms of impedance matching, gain and read range

Band-pass filter based on complementary split ring resonator

This letter presents a new circuit of the band-pass filter designed by using microstrip technology. Based on complementary split ring resonator and various series of optimization technic and a specific design method, a miniature band-pass filter with excellent electrical performances is achieved. First of all, the metamaterial unit cell is studied to obtain a desired resonant frequency and it is implemented in the ground plan in order to increase the characteristics of the bandpass behavior and decrease its operating frequencies. This proposed circuit is designed on an FR-4 substrate having a relative permittivity of 4.4 tangential losses of 0.025 and thickness of 1.6 mm. This filter is developed by using CST Microwave. The obtained features allow this filter to be used in diverse wireless applications such as IMT-E and WiMax

Design and Fabrication of the Novel Miniaturized Microstrip Coupler 3dB Using Stepped Impedance Resonators for the ISM Applications

In this work, a novel miniaturized compact coupler using the shunt-stubs artificial transimission lines with high and low impedances is presented. Design of the proposed coupler is accomplished by modifying the length and impedance of the branch lines in the conventional structure with the planar resonators in order to achieve branch line coupler with compact size and improvement of the performances. First part of this work is focusing on the theorical study of the proposed resonators where the equations are obtained. Secondly, the proposed coupler is designed on FR4 susbtrate, and simulated by using the EM Solver (ADS from Agilent technologies and CST microwave studio) in order to operate in the ISM band. The obtained results show good agreement with the simulations and the coupler shows a good perfo6rmance in the hole bandwidth. The size of the proposed coupler is reduced around 50% compared to the conventional design. The last part conerns the fabrication and test of the proposed coupler. The measurement and simulation results are in good agreements

A Miniature Microstrip Antenna Array using Circular Shaped Dumbbell for ISM Band Applications

The aim of this work is the achievement, and the validation of a small microstrip patch antenna array using a circular shaped dumbbell defected ground structure. This work has been dividing into two stages: The first step is to miniaturize a microstrip patch antenna resonating at 5.8GHz, which operate in the Industrial Scientific Medical band (ISM) and the second is to use a circular defected ground structure to shift the resonance frequency of the antenna array from 5.8GHz to 2.45GHz. At last, a miniaturization up to 74.47%, relative to the original microstrip antenna array has accomplished. The antenna structure has designed, optimized and miniaturized using CST MW Studio. The obtained results have compared with Ansoft’s HFSS electromagnetic solver. The antenna array has fabricated on FR-4 substrate, and its reflection coefficient is measured

A New Dual Band Printed Metamaterial Antenna for RFID Reader Applications

In this paper, we present a new dual band metamaterial printed antenna for radio frequency identification applications. The proposed antenna consists of two L-shaped slot in the radiating element for dual band operation and a complementary split ring resonator etched from the ground plane for size miniaturization. This antenna is designed and optimized by CST microwave studio on FR-4 substrate with thickness of 1.6 mm, dielectric constant of 4.4 and tangent loss of 0.025. A microstrip line with characteristic impedance of 50 ohms is used to feed this antenna. A prototype of the proposed antenna is fabricated to validate the simulation results. The measured and simulated results are in good agreement.

A novel printed multiband low cost antenna for WLAN and WiMAX applications

In this paper, a star-shaped microstrip patch antenna with modified ground structure consisting of an F-shaped slot printed in the ground is presented. The purpose of this design is to achieve and validate this microstrip multiband antenna. The entire area of the proposed antenna is 50x50mm2 and is printed on an FR-4 substrate and fed by a 50 Ohm microstrip line. This antenna has been analyzed and simulated for the WLAN and WiMAX applications. Simulation results show that the antenna has a good matching input impedance bandwidths for, S11<=-10 dB, covering the WLAN at 2.4/5.2 GHz and WiMAX at 3.5 GHz. Simulation has been done by using three different electromagnetic solvers for comparison CST-MW, Ansoft’s HFSS and ADS. After the realization, we have tested and validated this antenna. The measurement results of the antenna present a good agreement with the numerical results

Reduction of Mutual Coupling between Closely Spaced Microstrip Antennas Arrays Using Electromagnetic Band-gap (2D-EBG) Structures

Reducing mutual coupling is a key research area in design of compact microstrip antennas arrays. To minimize the overall size of the antennas arrays, the distance between them must be very small, as a result a strong mutual coupling is appears. Periodic structures can help to design a low profile of antennas arrays and enable to improve their performances by the suppression of surface waves propagation in a given frequency range. This paper proposes a novel configuration of mushroom-like electromagnetic band-gap (2D-EBG) structure created by microstrip technology placed between two antennas arrays to reduce the mutual coupling more than -33.24dB. When 13×2 EBG structures are used, the mutual coupling reduces to -59.36dB at the operation frequency 5.8GHz of the antennas arrays. A 26.12dB mutual coupling reduction is achieved, which proves that the surface wave is suppressed. The proposed configuration is designed, optimized, and miniaturized by using electromagnetic software CST Microwave Studio. The measured results show that there is a good agreement with the computed results

A new design of a microstrip rectenna at 5.8 GHz for wireless power transmission applications

Due to the ever-increasing power demand, the need of electricity and eco-friendly power in every nook and corner of the world, many reaserch topics have been devoted to deal with this problematic. This paper is taking part of the proposed solutions with the presentation of a novel 5.8 GHz rectenna system for wireless power transmission applications. In one hand, a miniaturized 5.8 GHz circular polarized patch antenna has been designed and simulated by using the Advanced Design System (ADS). In the other hand, a rectifier structure has been investigated and optimized by the use of the Harmonic Balance method available in ADS. The circuit is based on 5 HSMS2820 Schottky diodes implemented in a voltage multiplier topology and a load resistance of 1 KOhm. Both of the structures have been validated by simulation and experimental results and good agreement has been concluded

A novel design of a fractal antenna for IMT and WiMAX applications

In this paper, a new planar monopole antenna is designed and fabricated for IMT and WiMAX applications. The antenna is based on the use of Sierpinski triangle with a modified ground structure consisting of T-shaped and small rectangular slots printed in the ground. The entire area of the proposed antenna is 55x50mm2 and it is printed on an FR-4 epoxy substrate and fed by a 50 Ohm microstrip line. This new design helps in enhancing both the reflection coefficient and the bandwidth. The electrical performance of the fractal antenna is investigated by the use of CST-MW and HFSS. The simulated results present good performance in terms of matching input impedance and radiation pattern. The electromagnetic results of the fractal antenna are in a good agreement with measurement results