A miniature microstrip patch antenna array with defected ground structure

The aim of this work is to miniaturize a microstrip patch antenna array resonating at 10 GHz. It presents an improved method of size reduction of a microstrip antenna array with circular polarisation using Defected Ground Structure (DGS) which is used to perform serious LC resonance property in certain frequency. By integrating Defected Ground Structure elements, the resonance frequency was shifted from 10 GHz to 7.5 GHz. The proposed structure of DGS is incorporated in the ground plane of our array antenna. Prototype of the antenna was fabricated with FR4 substrate and tested. The simulation and measurement results were in good agreement

A New Design of a Wideband Miniature Antenna Array

In this work, we present a new configuration of a new miniature microstrip antenna array having a wide frequency band and with a circular polarization. The bandwidth is about 2GHz for a reflection coefficient under -10dB and centered on the ISM ‘Industrial Scientific Medical’ band at 5.8 GHz. To design such array, we have started the design by validating one antenna element at 10 GHz and after that by using the technique of defected ground, we have validated the antenna array in the frequency band [4 GHz -6 GHz] which will permit to miniature the dimensions. The final fabricated antenna array is mounted on an FR4 substrate, the whole area is 102.48 X 31.39 mm2  with a gain of 5dBi at 4GHz

The effect of tuning screws of the S-parameters of a 5G bandpass Filter

In this paper, the design and simulation of a symmetrical waveguide filter are presented based on the insertion loss method. The designed WR-34 waveguide filter is operating at 28 GHz, where its dimensions are a=4.32mm and b=8.64mm, a fractional bandwidth of 2.15% a return loss level better than 16 dB, a frequency range from 22Ghz to 33 GHz. The structure is a 5th-order bandpass filter with five resonators and six symmetrical circular inductive irises. In order to optimize the frequency response, five tuning screws were added to the center of each resonator, while two other screws were positioned before the first iris and the last iris from the wave ports. The simulation model of the filter is developed in two different simulators ANSYS high-frequency Structure Simulator (HFSS) and CST Studio Suite so as to validate the obtained results and to depict the effects of tuning screws on the S-parameters of the filter while generating scenarios depending on the depth of penetration of each screw

Design of a waveguide bandpass filter with inductive irises for a satellite application

This paper presents a synthesis, design, and simulation of a bandpass rectangular waveguide filter with symmetrical transverse discontinuities operating in the X-band (WR90) with a central frequency of 11GHz, a fractional bandwidth of 3.1%, an undulation ripple of 0.014 dB inside the bandwidth, and a return loss level around 15 dB. The simulation is effectuated under the HFSS environment, where the results of the S-parameters in dB and degree were verified using a CST environment. The obtained results had proven the validity of the conception of our structure since it has shown a symmetrical aspect around the central frequency in both 3D simulators after optimizing the overall dimensions of the irises, also our study has proved that irises are a reliable way to design bandpass filters especially, where their dimensions mainly affect the filter response in terms of the return loss quantity, the insertion loss, and the filter’s bandwidth

Design of a Circular Patch Antenna with a reflector for GPR applications

In this paper, a structure of a patch antenna operating at 0.5 GHz is proposed for ground-penetrating radar (GPR) applications, with an optimized performance at low frequencies. The structure was designed using FR4 substrate, with a 4.4 permittivity value, and a tangent loss equivalent to 0.021. The prototype design is backed by an optimized rectangular reflector, which has improved the antenna gain and directivity. The performance of the antenna is evaluated in terms of the return loss, gain, and the radiation pattern for two cases, with and without a reflector. When using the reflector, a good radiation pattern is obtained, a wide operational bandwidth ranging from 0.4GHz and 1.25 GHz is achieved, and an increased gain from 4.3 to 7.43dB was realized