scholarly journals A design of wideband high-power 3-dB quadrature coupler using defected ground structure for status data transmitting system

2020 ◽  
Vol 9 (1) ◽  
pp. 198-204
Author(s):  
The Anh Nguyen Dinh ◽  
Long Hoang Duc ◽  
Duong Bach Gia ◽  
Dragos Dancila

The paper presents a wideband 3-dB quadrature coupler designed for operation at 2 GHz. The presented coupler is based on a broadside-coupled suspended structure in combination with a proposed defected ground structure (DGS) allowing for high power, wide-band and improved harmonic suppression performance. The experimental results show 0.2 dB of insertion loss, return loss of better than 18 dB and isolation of better than 25 dB in the frequency range from 1.74 to 2.67 GHz. The proposed coupler is able to be integrated in the status data transmitting system, which is suitable for vessel monitoring. The fundamental characteristics of the implemented coupler have been measured and verified.

2018 ◽  
Vol 7 (2.8) ◽  
pp. 529 ◽  
Author(s):  
Ch Ramakrishna ◽  
G A.E.Satish Kumar ◽  
P Chandra Sekhar Reddy

This paper presents a band notched WLAN self complementaryultra wide band antenna for wireless applications. The proposed antenna encounters a return loss (RL) less than -10dB for entire ultra wideband frequency range except band notched frequency. This paper proposes a hexagon shape patch, edge feeding, self complementary technique and defective ground structure. The antenna has an overall dimensionof 28.3mm × 40mm × 2mm, builton  substrate FR4 with a relative dielectric permittivity 4.4. And framework is simulated finite element method with help of high frequency structured simulator HFSSv17.2.the proposed antenna achieves a impedance bandwidth of 8.6GHz,  band rejected WLAN frequency range 5.6-6.5 GHz with  vswr is less than 2.


2013 ◽  
Vol 385-386 ◽  
pp. 1292-1295
Author(s):  
Xu Han ◽  
Jian Hua Xu

A planar power divider operating over the whole Ku-band is presented. The proposed device utilizes a T-microstrip junction combined with defected ground structure and an elliptical patch at the centre of the T-junction. An isolation resistor is connected across the slotted ground plane. The simulated results of the divider show equal power split, insertion loss is less than 0.3dB, return loss of all ports are better than 15dB, and isolation is better than 15dB over the whole Ku-band.


Electronics ◽  
2021 ◽  
Vol 10 (23) ◽  
pp. 2927
Author(s):  
Luhua Zhang ◽  
Aiting Wu ◽  
Pengquan Zhang ◽  
Zhonghai Zhang

This letter proposes a multi-passband half-mode substrate integrated waveguide (HMSIW) filter based on the theory of odd and even mode analysis. The filter adopts a triangular HMSIW cavity cut along the diagonal of the rectangle. By etching two dual-mode resonators, the resonant mode of the HMSIW resonator is coupled with the odd-even mode of the dual-mode resonator to achieve multiple passbands. The defected ground structure (DGS) of the filter can reduce the resonance frequency of the HMSIW cavity without increasing the volume of the HMSIW cavity, making it easier to couple with the odd and even mode frequencies of the resonator. The input and output ports are directly coupled through a microstrip line. In this way, it adds an additional coupling path to the filter, which increases the out-of-band suppression without changing the performance in the passband, and improves the overall performance of the filter. To prove the feasibility of the above method, a multi-passband HMSIW filter was fabricated and tested. The center frequencies of the three passbands of the filter are 2.98 GHz, 4.78 GHz, and 6.62 GHz, respectively. The return loss in the passband is better than −15 dB, and the insertion loss is better than 2 dB. The measured results have a good agreement with the simulation results.


2019 ◽  
Vol 29 (03) ◽  
pp. 2050047
Author(s):  
Asmita Rajawat ◽  
P. K. Singhal

The design proposed and fabricated in this paper is a slotted wide-band rectenna with the inclusion of Defected Ground Structure (DGS) which can harvest RF energy in the frequency range of 5.336–6.194[Formula: see text]GHz with a center frequency of 5.8[Formula: see text]GHz. For the development of antenna, FR4 substrate having a dielectric permittivity of 4.3 has been adopted. Two parallel slots on the patch are incorporated on either side of the feed line to obtain the wide-band structure. Dumbbell-shaped DGS is also incorporated exactly underneath the feed line to increase the gain of the antenna. HSMS-285C Schottky diode has been used for the implementation of the rectifier circuit and a Greinacher voltage doubler has been chosen. ADS design software has been used for rectifier simulation and CST has been used for the designing of the antenna. Current behavior on the patch can be investigated to explore the wide-band mechanism. The antenna operates in the frequency range of 5.336–6.194[Formula: see text]GHz and with VSWR less than 2, which corresponds to 16.07% impedance bandwidth. The antenna achieves a gain of 6.189[Formula: see text]dB and a directivity of 8.776[Formula: see text]dBi. The conversion efficiency of the rectifier was optimized to 75% at 5.8[Formula: see text]GHz. The proposed design gave an output of 3.2[Formula: see text]V which can be used under numerous energy harvesting and wireless power transmission applications.


Author(s):  
Yatindra Gaurav ◽  
R.K. Chauhan

This paper presents a compact design of an ultra wide band bandpass filters with a notch band using interdigital structure. The aim of the design is to reduce the size of filter, reduce the complexity of the design, and improve the performance of filter response. The proposed filter comprises of a rectangular resonator sandwiched between Interdigital structures, with rectangular slot as defected microstrip structure at the input and output ports. This design has been used for the first time to achieve the above aim. The advantage with this design is that, it does not use any via or defected ground structure. The insertion loss of proposed filter, in passband between 3.1 GHz to 10.8 GHz, is less than 0.7dB, and for the notched band it is 21.5 dB centred at 7.9 GHz. The proposed filter is fabricated, tested and compared with simulated results. The proposed design was small in size with less complexity, and shows performance better than the other designs available in the literatures at this dimension.


In this paper, a compact microstrip patch has a slot associated with the Defected Ground Structure radiator is presented. Instead of semi-infinite ground plane, the proposed antenna adopts the defected ground plane. The Radiating patch mendacity on the FR-4 substrate which is having dielectric constant of 4.4, thereby provides good bandwidth. This microstrip antenna is designed for wide bandwidth applications in range of 5.5GHz to 7.25GHz. Proposed work introduces a methodology wherein reducing of structure’s increase the bandwidth as well as return loss with defected ground structure (DGS).However since communication systems require small size, broad band and multiband antennas, monopoles have to be ensued for fabricating broad-band and wide-band antennas. In the proposed work investigations are carried out to design a new antenna with broad-band properties. Simulations are carried out via An soft HFSS electromagnetic simulator software- fabricated on FR-4 Substrate and tested with Vector network Analyzer. Measurement and Simulation results obtained prove the applicability of proposed antenna in 5.5GHz to 7.25GHz frequency range with a return loss of -31.3dB and 11.5dB etc. Microstrip feed line technique is used to feed the antenna with 50Ω impedance.


Author(s):  
Gulzar Ahmed ◽  
Muhammad Inayatullah Babar ◽  
Sadique Ali ◽  
Faheem Ali

Low BW (Bandwidth) is a major limitation of microstrip antennas. A patch antenna having a large BW for Ku band applications is demonstrated in this manuscript. The skills of Defected Ground Structure (DGS) and defected driven patch were engaged to widen its BW. Four slices have also been confiscated from the ground for upgrading various characteristics. It is established on the basis of this study that it can be employed in spectrum defining and bands. It puts forward an impedance BW of 8GHz, which is appropriate for numerous applications. The ground/substrate of the structure under consideration is 22×10-3m long and 10×103m wide and these specifications imply that the volume of this design is very small. The entire structure’s utmost thickness is 1.67×10-3m. It can be easily installed in relevant handy electronic devices. Investigations and analysis in this case are made with computer software known as Computer Simulation Technology. The simulated design exhibits a very good gain and efficiency. Deviation in the gain of the simulated design was from 4.4 7.3dBi and it guaranteed the highest efficiency of 98.6%. Some minor changes in the antenna resulted in expansion in the BW from 8GHz to 14GHz. The return loss which was recorded at frequency of 18.15GHz went to 48.97dB and the mentioned changes assured the uppermost efficiency of 83.1%. The fabricated antenna achieved a bandwidth of 28GHz which is far better than the simulated bandwidth.


2019 ◽  
Vol 14 (4) ◽  
pp. 448-455 ◽  
Author(s):  
Nanang Ismail ◽  
Teddy Surya Gunawan ◽  
Santi Kartika S ◽  
Teguh Praludi ◽  
Eki A.Z. Hamidi

Radar has been widely used in many fields, such as telecommunication, military applications, and navigation. The filter is one of the most important parts of a radar system, in which it selects the necessary frequency and blocks others. This paper presents a novel yet simple filter design for S-band radar in the frequency range of 2.9 to 3.1 GHz. The center frequency of the filter was designed at 3 GHz with a bandwidth of 200 MHz, insertion loss larger than -3 dB and return loss less than -20 dB. Fifth order microstrip hairpin bandpass filter (BPF) was designed and implemented on Rogers 4350B substrate which has a dielectric relative constant value of (εr)= 3.48 and substrate thickness of (h) =1.524 mm. One element of the square groove was added as Defected Ground Structure (DGS) which can decrease the filter size, reduce harmonization, and increase return loss. Two scenarios were used in the measurement, i.e. with and without enclosed aluminum casing. Results showed that BPF without casing obtained the insertion loss of -1.748 dB at 2.785 GHz and return loss of -21.257 dB in the frequency range between 2.785 to 2.932 GHz. On the other hand, BPF with casing shows a better performance, in which it obtained the insertion loss of -1.643 dB at 2.921 GHz and return loss of -19.529 in the frequency range between 2.820 to 3.021 GHz. Although there is small displacement of frequency and response value between the simulation and implementation, our BPF has the ability to work on S-band radar with a frequency range of 2 to 4 GHz. 


Author(s):  
Saida Elajoumi ◽  
A. Tajmouati ◽  
J. Zbitou ◽  
A. Errkik ◽  
L. El Abdellaoui ◽  
...  

<p>This paper presents the design of new compact printed antennas for Ultra Wide Band applications, fed with a microstrip-line. The proposed designs consist of a patch antenna with defected ground, which are fed by 50Ω microstrip transmission line. The frequency range is 3.1-10.6 GHz which is the Federal Communication Commission (FCC) band of UWB. The proposed antennas are easy for integration with microwave circuits. They are validated into simulation by using two electromagnetic solvers CST-MW and Ansoft HFSS. The simulated input impedance bandwidth ranging 3GHz to more than 14 GHz is obtained with return loss less -10dB, and exhibits good UWB characteristics. The measured parameters are good agreement with the simulation. Therefore these antennas offer excellent performance for UWB system.</p>


Sign in / Sign up

Export Citation Format

Share Document