This document provides an overview of defected ground structures (DGS) for microwave circuit applications. It discusses how DGS units are etched patterns in circuit ground planes that can alter transmission line properties like capacitance and inductance. Various DGS unit shapes are presented, including dumbbell, spiral, arrowhead, and interdigital designs. Periodic DGS involve cascading multiple DGS units and can further widen stopbands and reduce circuit size. The document outlines the basic concepts and transmission characteristics of DGS and surveys their applications in microwave components.
Design and analysing of compact microstrip antenna with defected ground struc...eSAT Journals
Abstract
In this paper a small size microstrip antenna with DGS (Defected ground structure) is designed and analyzed for UWB(Ultra
Wide Band) application. This antenna cover the complete frequency range of 3.1 to 10.6 GHz with a very small geometry as
compared to a conventional antenna Dielectric substrate use in this antenna is Fr-4. This antenna is designed with a dimension is
36mm × 34 mm on a dielectric substrate Fr-4 whose permittivity εr =4.4 and height h = 1.6 mm. The result for return losses and
radiation patterns is simulated by using HFSS (High Frequency structure simulation) software. The High frequency structure
simulator is employed to analyze the planned antenna and simulated results on return loss, The ground element of the proposed
antenna is taken in the form of defected ground structure (DGS).
Keywords: Microstrip Antenna, UWB, DGS, Wide band, HFSS
Artificial intelligence in the design of microstrip antennaRaj Kumar Thenua
This work presents a Neural Network model for the design of Microstrip Antenna for a desired frequency between 3.5 GHz to 5.5 GHz. The results obtained from the proposed method are compared with the results of IE3D and are found to be in good agreement. The advantage of the proposed method lies with the fact that the various parameters required for the design of specific Microstrip antenna at a particular frequency of interest can be easily extracted without going into the rigorous time consuming, iterative design procedures using a costly software package. In this work, a general design procedure is suggested for the Microstrip antennas using artificial neural networks and this is demonstrated using the rectangular patch geometry.
Miniaturized Microstrip Patch Antenna Array at 3.8 GHz for WiMax Applicationiosrjce
The aim of this work is to miniaturize microstrip patch antenna array resonating at 3.8 GHz
suitable for WiMax application using defected ground structure (DGS).The DGS has been employed to shift the
resonance frequency of an initial microstrip antenna array from 5.2 GHz to 3.8 GHz by disturbing the
antenna’s current distribution. The proposed DGS is integrated in the ground plane under the patch antenna
array for size reduction. Finally, the miniaturization up to 45% with respect to the conventional microstrip
antenna is successfully accomplished. A prototype of the antenna was fabricated with the RT-Duriod substrate.
This technique has been validated experimentally and measured results were found to be in good agreement
with simulated results.
Design and Analysis of Microstrip Patch Antenna with Optimization for Wireles...ijsrd.com
In this paper, design of conventional Rectangular patch Microstrip antenna has been proposed and its performance is analyzed. The design parameters of antenna are selected to achieve compact dimensions as well as best possible characteristics such as high gain, increased bandwidth with minimum return loss. Hence improved design has been demonstrated over elementary one. These antennas have been designed at 2.4GHz which enables its usage in wireless communication domain such as Wireless Local Area Network (WLAN). The antenna design and performance are analyzed using Ansoft HFSS software. These antennas can be used for many wireless communication systems.
Design and analysing of compact microstrip antenna with defected ground struc...eSAT Journals
Abstract
In this paper a small size microstrip antenna with DGS (Defected ground structure) is designed and analyzed for UWB(Ultra
Wide Band) application. This antenna cover the complete frequency range of 3.1 to 10.6 GHz with a very small geometry as
compared to a conventional antenna Dielectric substrate use in this antenna is Fr-4. This antenna is designed with a dimension is
36mm × 34 mm on a dielectric substrate Fr-4 whose permittivity εr =4.4 and height h = 1.6 mm. The result for return losses and
radiation patterns is simulated by using HFSS (High Frequency structure simulation) software. The High frequency structure
simulator is employed to analyze the planned antenna and simulated results on return loss, The ground element of the proposed
antenna is taken in the form of defected ground structure (DGS).
Keywords: Microstrip Antenna, UWB, DGS, Wide band, HFSS
Artificial intelligence in the design of microstrip antennaRaj Kumar Thenua
This work presents a Neural Network model for the design of Microstrip Antenna for a desired frequency between 3.5 GHz to 5.5 GHz. The results obtained from the proposed method are compared with the results of IE3D and are found to be in good agreement. The advantage of the proposed method lies with the fact that the various parameters required for the design of specific Microstrip antenna at a particular frequency of interest can be easily extracted without going into the rigorous time consuming, iterative design procedures using a costly software package. In this work, a general design procedure is suggested for the Microstrip antennas using artificial neural networks and this is demonstrated using the rectangular patch geometry.
Miniaturized Microstrip Patch Antenna Array at 3.8 GHz for WiMax Applicationiosrjce
The aim of this work is to miniaturize microstrip patch antenna array resonating at 3.8 GHz
suitable for WiMax application using defected ground structure (DGS).The DGS has been employed to shift the
resonance frequency of an initial microstrip antenna array from 5.2 GHz to 3.8 GHz by disturbing the
antenna’s current distribution. The proposed DGS is integrated in the ground plane under the patch antenna
array for size reduction. Finally, the miniaturization up to 45% with respect to the conventional microstrip
antenna is successfully accomplished. A prototype of the antenna was fabricated with the RT-Duriod substrate.
This technique has been validated experimentally and measured results were found to be in good agreement
with simulated results.
Design and Analysis of Microstrip Patch Antenna with Optimization for Wireles...ijsrd.com
In this paper, design of conventional Rectangular patch Microstrip antenna has been proposed and its performance is analyzed. The design parameters of antenna are selected to achieve compact dimensions as well as best possible characteristics such as high gain, increased bandwidth with minimum return loss. Hence improved design has been demonstrated over elementary one. These antennas have been designed at 2.4GHz which enables its usage in wireless communication domain such as Wireless Local Area Network (WLAN). The antenna design and performance are analyzed using Ansoft HFSS software. These antennas can be used for many wireless communication systems.
Design of a Rectangular Microstrip Patch Antenna Using Inset Feed TechniqueIOSR Journals
Abstract : Today in the world of communication systems the most widely researched area is of wireless technology and a study of communication systems is incomplete without an understanding of the operation of the antennas. In the recent years of development in communication systems a need for the development of lightweight, compact and cost-effective antennas that are capable of maintaining high performance over a wide spectrum of frequencies. This technological trend has focused much effort into the design of a Micro strip patch antenna. In this work, the simulation tool of IE3D is used to study the performance and gain of the rectangular Microstrip patch antenna. The design and simulation of patch antennas is widely used in mobile cellular phones today, and our emphasis in this work is on optimization of a 2.4 GHz rectangular Microstrip patch antenna. The return loss and the various gain plots have been studied along with the radiation patterns. Keywords: Gain, Inset feed, Patch antenna, Radiation pattern, Return Loss.
Designing of Rectangular Microstrip Patch Antenna for C-Band ApplicationIJMER
Microstrip patch antenna becoming very popular day by day because of its ease of analysis, fabrication, low cast, light weight easy to feed and their attractive radiation characteristics. In this paper we proposed the designed of rectangular microstrip patch antenna to operate at frequency range 5-6 GHz. The simulation is carried out using high frequency simulation structure (HFSS) program.
The antenna is based on the modified epoxy substrate with dielectric constant of approximate 4.4. After simulation rectangular microstrip antenna performs characteristics such as VSWR & return loss smith chart
A small H-shaped microstrip patch antenna (MPA) with enhanced bandwidth is presented. The H-shaped antenna is first studied and then fully simulated by HFSS. A dual U slot H patch configuration is proposed to increase the narrow bandwidth, radiation efficiency and directivity. A novel H-shaped patch antenna suitable for wireless and satellite communications is presented. This paper presents the dual U slot H-shaped microstrip patch antenna feed by transmission line. The decrease in the prices of handheld devices and services has made available on the move internet and web services facility to the customers, small antennas requirement are increasing. In this paper H-shaped patch antenna is designed using FR4 substrate. The proposed modified H shaped antenna is designed and simulated using HFSS and caters to various wireless applications such as WiMAX, Wi-Fi, UMTS and Digital Multimedia Broadcasting (DMB) e.g. T V, etc.
E shape microstrip patch antenna design for wimax applications, international...Sk Sohag
This paper presents the design & simulation of E-shape microstrip patch antenna exhibiting wideband operating frequencies for various wireless applications. This antenna will provide the wide bandwidth which is required in various applications like remote sensing, biomedical application, mobile radio satellite, wireless communication etc. The coaxial feed or probe feed technique is used in the experiment. The performance of the designed antenna was analyzed in terms of bandwidth, gain, return loss, VSWR, and radiation pattern. The design is optimized to meet the best possible result. The proposed antenna is designed by air substrate which has a dielectric constant of 1.0006. The results show the wideband antenna is able to operate from 8.80 to 13.49 GHz frequency band with optimum frequency at 8.73 GHz.
Design of Reconfigurable Microstrip Patch Antenna for WLAN ApplicationEditor IJMTER
In this paper we propose a rectangular microstrip patch antenna with inset fed which can
operate at 2.4 GHz (IEEE 802.11b) & 5.8 GHz (IEEE 802.11a) WLAN applications. Various slot is
cut into the antenna structure which changes the surface current path resulting in dual resonant
frequency. Further by embedding any switch into a slot, reconfiguration can be achieved i.e. the
antenna can only be used in unlicensed 2.4 GHz band. The achieved directivity is greater than 5db and
the bandwidth obtained is much greater than the required bandwidth. The proposed antenna is
simulated using High Frequency Structure Simulator.
Design of octagon shape microstrip patch antenna for multiband applicationvishant choudhary
In this Research paper .Three antenna is shows which is In a zero slot Microstrip patch antenna three resonant frequency bands occur, In single slot Microstrip patch antenna five resonant bands occurs and In five slots Microstrip antenna six resonant frequency bands occurs. These antennas can be used at various application such as GSM and WLAN-IEEE-802.11(a, b, g and n). Therefore the proposed antennas have satisfactory performance for use as a multiband communication antenna.
Metamaterial loaded microstrip patch antenna for quad band operationeSAT Journals
Abstract In this paper, a novel design for miniaturization of microstrip patch antenna with multiband operation of microstrip antenna is proposed. The technique is based on etching out of Complimentary Split-Ring Resonator (CSRR) on the radiating edge of the patch antenna. Numerical simulations are presented for a patch antenna with and without CSRRs by using IE3D simulation software and measured practically. The measured results shows that antenna with CSRRs on the radiating edge of the patch antenna is resonating at four different frequency points i.e., 4.96GHz, 6.05GHz, 8.62GHz and 11.25GHz., whereas, antenna without CSRR i.e., conventional microstrip antenna is resonating at 5.98GHz. The size reduction of 16.92% is achieved and the antenna gives the overall bandwidth of 17.88%. These antennas find application in Wireless Communications. Keywords: microstrip antenna, CSRR, return loss, miniaturization, bandwidth.
Coupled Line Band Pass Filter with Defected Ground Structure for Wide Band Ap...IJERA Editor
In this paper a novel wideband microstrip band pass filter is proposed. The band pass filter is designed with coupling between two L-shaped microstriplines and is terminated with a high impedance line. The three circle shapes are etched out at the ground plane and is called defected ground structure (DGS), which provides better return loss as well as it reduces harmonics. Simulated and measured results both are in true agreement with each other. Results show that the defected microstrip filter has a good performance, including a wide pass band of 3.0 GHz to 5.6 GHz at 3dB cut off frequencies with bandwidth of 2.6 GHz, and a small insertion loss. The return loss is found to be higher than 15 dB.
A novel compact CPW tunable stop band filter using a new Z-DGS-resonator for ...TELKOMNIKA JOURNAL
The paper presents a novel very compact CPW bandstop filter. The designed structure consists of one unit of new Z-DGS resonator, placed on top layer of ground plane between the input and output this structure, which is excited by 50-ohm coplanar line. The designed filter can be used in X-Band applications as the band stop can be shifted to any other desired frequency by tuning the length of the Z-DGS. The proposed filter topology has as benefits good performances in terms of wide stop-band rejection, low insertion loss, high return loss, simple design and more small size (17.908×10 mm2) compared to other previous works those reported in literature. The stop-band width is from 3.96 GHz to 6.21 GHz, exhibits a 22.25-dB rejection bandwidth of 45% with high selectivity characteristic at the center frequency of 5.05 GHz.
Design of a Rectangular Microstrip Patch Antenna Using Inset Feed TechniqueIOSR Journals
Abstract : Today in the world of communication systems the most widely researched area is of wireless technology and a study of communication systems is incomplete without an understanding of the operation of the antennas. In the recent years of development in communication systems a need for the development of lightweight, compact and cost-effective antennas that are capable of maintaining high performance over a wide spectrum of frequencies. This technological trend has focused much effort into the design of a Micro strip patch antenna. In this work, the simulation tool of IE3D is used to study the performance and gain of the rectangular Microstrip patch antenna. The design and simulation of patch antennas is widely used in mobile cellular phones today, and our emphasis in this work is on optimization of a 2.4 GHz rectangular Microstrip patch antenna. The return loss and the various gain plots have been studied along with the radiation patterns. Keywords: Gain, Inset feed, Patch antenna, Radiation pattern, Return Loss.
Designing of Rectangular Microstrip Patch Antenna for C-Band ApplicationIJMER
Microstrip patch antenna becoming very popular day by day because of its ease of analysis, fabrication, low cast, light weight easy to feed and their attractive radiation characteristics. In this paper we proposed the designed of rectangular microstrip patch antenna to operate at frequency range 5-6 GHz. The simulation is carried out using high frequency simulation structure (HFSS) program.
The antenna is based on the modified epoxy substrate with dielectric constant of approximate 4.4. After simulation rectangular microstrip antenna performs characteristics such as VSWR & return loss smith chart
A small H-shaped microstrip patch antenna (MPA) with enhanced bandwidth is presented. The H-shaped antenna is first studied and then fully simulated by HFSS. A dual U slot H patch configuration is proposed to increase the narrow bandwidth, radiation efficiency and directivity. A novel H-shaped patch antenna suitable for wireless and satellite communications is presented. This paper presents the dual U slot H-shaped microstrip patch antenna feed by transmission line. The decrease in the prices of handheld devices and services has made available on the move internet and web services facility to the customers, small antennas requirement are increasing. In this paper H-shaped patch antenna is designed using FR4 substrate. The proposed modified H shaped antenna is designed and simulated using HFSS and caters to various wireless applications such as WiMAX, Wi-Fi, UMTS and Digital Multimedia Broadcasting (DMB) e.g. T V, etc.
E shape microstrip patch antenna design for wimax applications, international...Sk Sohag
This paper presents the design & simulation of E-shape microstrip patch antenna exhibiting wideband operating frequencies for various wireless applications. This antenna will provide the wide bandwidth which is required in various applications like remote sensing, biomedical application, mobile radio satellite, wireless communication etc. The coaxial feed or probe feed technique is used in the experiment. The performance of the designed antenna was analyzed in terms of bandwidth, gain, return loss, VSWR, and radiation pattern. The design is optimized to meet the best possible result. The proposed antenna is designed by air substrate which has a dielectric constant of 1.0006. The results show the wideband antenna is able to operate from 8.80 to 13.49 GHz frequency band with optimum frequency at 8.73 GHz.
Design of Reconfigurable Microstrip Patch Antenna for WLAN ApplicationEditor IJMTER
In this paper we propose a rectangular microstrip patch antenna with inset fed which can
operate at 2.4 GHz (IEEE 802.11b) & 5.8 GHz (IEEE 802.11a) WLAN applications. Various slot is
cut into the antenna structure which changes the surface current path resulting in dual resonant
frequency. Further by embedding any switch into a slot, reconfiguration can be achieved i.e. the
antenna can only be used in unlicensed 2.4 GHz band. The achieved directivity is greater than 5db and
the bandwidth obtained is much greater than the required bandwidth. The proposed antenna is
simulated using High Frequency Structure Simulator.
Design of octagon shape microstrip patch antenna for multiband applicationvishant choudhary
In this Research paper .Three antenna is shows which is In a zero slot Microstrip patch antenna three resonant frequency bands occur, In single slot Microstrip patch antenna five resonant bands occurs and In five slots Microstrip antenna six resonant frequency bands occurs. These antennas can be used at various application such as GSM and WLAN-IEEE-802.11(a, b, g and n). Therefore the proposed antennas have satisfactory performance for use as a multiband communication antenna.
Metamaterial loaded microstrip patch antenna for quad band operationeSAT Journals
Abstract In this paper, a novel design for miniaturization of microstrip patch antenna with multiband operation of microstrip antenna is proposed. The technique is based on etching out of Complimentary Split-Ring Resonator (CSRR) on the radiating edge of the patch antenna. Numerical simulations are presented for a patch antenna with and without CSRRs by using IE3D simulation software and measured practically. The measured results shows that antenna with CSRRs on the radiating edge of the patch antenna is resonating at four different frequency points i.e., 4.96GHz, 6.05GHz, 8.62GHz and 11.25GHz., whereas, antenna without CSRR i.e., conventional microstrip antenna is resonating at 5.98GHz. The size reduction of 16.92% is achieved and the antenna gives the overall bandwidth of 17.88%. These antennas find application in Wireless Communications. Keywords: microstrip antenna, CSRR, return loss, miniaturization, bandwidth.
Coupled Line Band Pass Filter with Defected Ground Structure for Wide Band Ap...IJERA Editor
In this paper a novel wideband microstrip band pass filter is proposed. The band pass filter is designed with coupling between two L-shaped microstriplines and is terminated with a high impedance line. The three circle shapes are etched out at the ground plane and is called defected ground structure (DGS), which provides better return loss as well as it reduces harmonics. Simulated and measured results both are in true agreement with each other. Results show that the defected microstrip filter has a good performance, including a wide pass band of 3.0 GHz to 5.6 GHz at 3dB cut off frequencies with bandwidth of 2.6 GHz, and a small insertion loss. The return loss is found to be higher than 15 dB.
A novel compact CPW tunable stop band filter using a new Z-DGS-resonator for ...TELKOMNIKA JOURNAL
The paper presents a novel very compact CPW bandstop filter. The designed structure consists of one unit of new Z-DGS resonator, placed on top layer of ground plane between the input and output this structure, which is excited by 50-ohm coplanar line. The designed filter can be used in X-Band applications as the band stop can be shifted to any other desired frequency by tuning the length of the Z-DGS. The proposed filter topology has as benefits good performances in terms of wide stop-band rejection, low insertion loss, high return loss, simple design and more small size (17.908×10 mm2) compared to other previous works those reported in literature. The stop-band width is from 3.96 GHz to 6.21 GHz, exhibits a 22.25-dB rejection bandwidth of 45% with high selectivity characteristic at the center frequency of 5.05 GHz.
Bandwidth enhancement and miniaturization of circular-shaped microstrip anten...IJECEIAES
In this paper, circular-shaped microstrip antenna was simulated, fabricated, and measured accordingly. As the novelty, to enhance bandwidth and reduce antenna size, beleved half-cut microstrip structure is proposed. Further, this proposed antenna structure will be applied to multiple input multiple output (MIMO) antenna 2´2. Therefore, this research was investigated conventional circular shape antenna (CCSA), circular shaped beleved antenna (CSBA), and MIMO circular shaped beleved antenna (MIMO-CBSA) as Model 1, Model 2, and Model 3, respectively. An FR4 substrate with er= 4.4, thickness h=1.6 mm, and tan d=0.0265 was used. The simulation has been conducted using Advanced Design System (ADS). The antenna CCSA/CSBA/ MIMO-CBSA achieve 1.831GHz/2.265 GHz/2.256 GHz, -15.13dB/-17.37dB/-17.25 dB, 1.42/1.31/1.33, and 1.474/2.332/2.322 for center frequency, reflection coefficient, VSWR, and bandwidth, respectively. This antenna has a size 63x90 mm and 51.5x90 mm for CCSA (Model 1) and CSBA (Model 2), respectively. After the structure of MIMO 2´2 was applied, the size of antenna MIMO-CBSA (Model 3) became 180 mm x 180 mm with a mutual coupling (S21)=-26.18 dB and mutual coupling (S31)=-26.41 dB. The result showed that proposed antenna CSBA (Model 2) has wider-bandwidth of 58,2% and smaller-size of 18.2%. Furthermore, after CSBA (Model 2) structure was applied to MIMO 2´2 (Model 3) and the MIMO antenna obtain good mutual coupling (<-15dB). Moreover, the measured results are good agreement with the simulated results. In conclusion, all of these advantages make it particularly valuable in multistandard antenna applications design such as GSM950, WCDMA1800, LTE2300, and WLAN2400.
Antenna is the most important part of wireless communication. The recent growth in this industry makes the antenna more advanced and reliable. In various fields we need the use of highly characteristics antennas and these characteristics are based upon some parameters like bandwidth, gain, directivity etc. As compared to other antennas microstrip antenna can make possible to achieve the required characteristics for efficient communication because they are easily to fabricate and reduces the cost also. To make the microstrip antenna more advanced it use defected ground structure (DGS). The DGS structures are introduce to improve the performance of planar array antenna in terms of return loss, gain, directivity and voltage standing wave ratio. The goal of this paper is to understand the mathematical terms of antenna and feeding techniques so that it possible to know how to make the Microstrip antenna with DGS as more highly characterized antenna.
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Regression model for analyzing the dgs structures propagation characterisitcseSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Microstrip to Parallel-Strip Nonlinear Transition Balun with Stubs and DGS fo...TELKOMNIKA JOURNAL
Three tapered baluns with nonlinear transition are developed for harmonic suppression in dipole antenna. The first balun consists of an exponential profile with the size of a quarter–wavelength for both the height and width with a wideband characteristic. However, for some applications such as narrowband harmonic suppression antennas and wideband-to-narrowband reconfigurable antennas, the suppression of higher operating band is desired. By employing stubs-filter and a defected ground structure (DGS), two narrowband tapered baluns are produced. They are named as an exponential balun-stub and an exponential balun-DGS, respectively, that operate from 1 to 2 GHz. A simulated and measured results that based on the reflection coefficient is found to be better than -10 dB from 1 to 2 GHz. The employment of the stubs and DGS have enabled these baluns to have the capability to reject the unwanted higher frequency band from 2.0 to 10 GHz. Finally, the proposed baluns are employed as a feeding circuit for an ultra wideband (UWB) circular dipole antenna that produces a reasonable outcome.
A Novel Wideband Bandpass Filter using H-shaped DGSIJECEIAES
This paper presents a novel compact wide-band bandpass filter (BPF) having good selectivity. It is designed using a dual-plane structure which consists of a parallelcoupled microstrip line on the upper surface and three H-shape defected ground structure (DGS) on the ground plane. By adding three H-shape DGS units on the ground plane, then properly adjusting their dimensions and position, the bandwidth and selectivity of the designed filter can be significantly improved. A compact prototype of wide-band microstrip bandpass filter has been designed, fabricated and measured to apply for the wireless systems. The filter shows a center frequency at 4.8 GHz, passband from 2.8 GHz to 6.8 GHz with maximum insertion loss and return loss of 0.8 dB and 40 dB, respectively. The measured results agrees well with the theoretical expectations validating the proposed design.
Size Reduction and Gain Enhancement of a Microstrip Antenna using Partially D...IJECEIAES
Microwave engineers have been known to designedly created defects in the shape of carved out patterns on the ground plane of microstrip circuits and transmission lines for a long time, although their implementations to the antennas are comparatively new. The term Defected Ground Structure (DGS), precisely means a single or finite number of defects. At the beginning, DGS was employed underneath printed feed lines to suppress higher harmonics. Then DGS was directly integrated with antennas to improve the radiation characteristics, gain and to suppress mutual coupling between adjacent elements. Since then, the DGS techniques have been explored extensively and have led to many possible applications in the communication industry. The objective of this paper is to design and investigate microstrip patch antenna that operates at 2.4 GHz for Wireless Local Area Network WLAN IEEE 802.11b/g/n, ,Zigbee, Wireless HART, Bluetooth and several proprietary technologies that operate in the 2.4 GHz band. The design of the proposed antenna involves using partially Defected Ground Structure and circular/cross slots and compare it to the traditional microstrip patch antenna. The results show improvement in both the gain of 3.45 dB and the S11 response of -22.3 dB along with reduction in the overall dimensions of the antenna. As a conclusion, the performance of the antenna has been improved through the incorporation with the DGS and slots structures regarding the S11 response and the gain. The proposed antenna become more compact. Finally, the radiation pattern of proposed antenna has remained directional in spite of adding slots on the ground plane.
Design of miniaturized patch crossover based on superformula slot shapesIJECEIAES
In this paper, miniaturized microstrip crossover circuits are proposed using slots shapes obtained using the superformula. The design starts by using a conventional half-wavelength square patch crossover. For miniaturization purposes, different superformula slot shapes are introduced on the square patch. The proposed crossovers are designed to operate at 2.4 GHz using a 0.8 mm thick FR-4 substrate with a relative permittivity of 4.4. The designs are simulated using the high frequency structure simulator (HFSS). One of the miniaturized designs is fabricated and its scattering parameters are measured using a vector network analyzer. Simulated and measured results agree very well. At the design frequency, the measured input port matching is better than ˗19 dB, while 𝑆12, 𝑆13 and 𝑆14 have the values of ˗12 dB, ˗2.2 dB and ˗10 dB, respectively. Furthermore, a 71% size reduction is achieved as compared to the conventional crossover area.
The Approach on Influence of Biasing Circuit in Wideband Low Noise Amplifier ...IJEACS
This proposed work investigates the effects of biasing
circuit in the ultra-wideband microwave low noise amplifier
which operates between 3GHz to 10GHz. The complete circuit is
visualized the importance of every component in the design with
respect to linear measurements like Gain, Noise Figure, Return
loss under unconditionally stable condition. The design and
realization are made by using Hybrid Microwave integrated
circuit in AWR microwave office. The thing that is absolutely
necessary and frequently the difficult step in the design of an
LNA is 'biasing circuit design'. The difficulty situation arises
because traditional methods LNA by using S-parameters data
files in EDA tools provides almost all linear measurements.
Hence a number of time consuming iterations of different biasing
circuits with optimization methods may be required to reach
targeted specifications with the fixed operating point at the
desired points in the load line. Considering this behavior, various
alternate biasing circuit schemes are prepared and founded the
results associated with it. Furthermore, this paper unmistakably
clarifies the impacts of the biasing circuit by utilizing
intermodulation and harmonics distortion technique for
portrayal characterization. Different cases and sorts of the
biasing circuits with various biasing focuses have been tested and given clear perspective of the biasing ideas.
A novel cross-coupled microstrip bandpass filter with hairpin-DGS resonators ...TELKOMNIKA JOURNAL
This paper introduces a new design of a cross-coupled microstrip bandpass filter (MBPF) based on hairpin defected ground structure (DGS) resonators using accurate coupling matrix (CM) technique for microwave communication systems. The article presents the equivalent circuit of the suggested MBPF based on the DGS equivalent circuit model derived from the equivalent inductance and capacitance that occurs despite the presence of the slots disrupting the current in the ground layer. The paper investigates also the different external coupling mechanisms that the feed configuration affects significantly the filter response. In this paper, a four order Chebyshev topology has been adopted for designing the filter to suppress harmonics and achieve a very compact size and a wide stopband with two transmission zeros.
In this paper, a novel multi-frequency microstrip antenna with complementary ring slot resonator (CRSR) structure that satisfies Bluetooth, worldwide interoperability for microwave access (WiMAX), and wireless local area network (WLAN) applications is proposed. The conventional antenna consists of a circular microstrip patch at a resonance frequency band of 2.5 GHz. By loading two CRSR at the radiating element, three operating frequency bands 2.5 GHz, 3.6 GHz, and 5.2 GHz are achieved. The operational bands covered by the antenna are Bluetooth 2.5 GHz, WiMAX 3.6 GHz, and WLAN 5.2 GHz. The insertion of CRSR to patch antenna has made it possible to compact and simple design, and miniaturized antenna for cognitive radio. Moreover, the directivity of the proposed antenna is adequate with acceptable radiation properties and perfectly matches with the simulated and measured results.
Design and Analysis of Broadband Elliptical Microstrip Patch Antenna for Wire...TELKOMNIKA JOURNAL
In this paper presents the design and manufacture of a new broadband elliptical patch antenna
with a microstrip feed line and optimum antenna parameters. The antenna dimension of
(30 × 21 × 1.6) 푚푚3 and fabricated on an FR-4 epoxy substrate having relative dielectric constant 휀푟=4.3,
loss tangent tan (δ)=0.002 and the feed line used has characteristic impedance of 50Ω.The designed
antenna has the capability of operating in the bandwidth (6.95-30.94) GHz and the gain (6.8) dBi. The
antenna performance was modified by inserting a slots in the ground plane to achieve impedance
bandwidth (when S11≤-10dB) and slots to patch to improve the gain. The modified antenna was designed
to be used for fifth generation (5G) mobile communication. The simulation results are obtained using CST
software.
Substrate integrate waveguide and microstrip antennas at 28 GHzjournalBEEI
In this paper, two antennas are designed using substrate integrated waveguide (SIW) and microstrip technology at 28 GHz. Parametric study for both antennas is presented to demonstrate the performance at millimeter wave frequency for wireless communication network (5G application). Roger RT5880 substrates with permittivity 2.2 and loss tangent 0.0009 are used to implement the antennas with two thicknesses of 0.508 mm and 0.127 mm respectively. Both antennas have the same size of substrate 12x12 mm with a full ground plane was used. Structures designs have been done by using computer simulation technology (CST). The simulation results showed that the antenna with SIW and roger RT 5880 substrate thickness 0.508 has better performance in term of return loss and radiation pattern than the microstrip patch antenna at 28 GHz. A return loss more than -10 dB and the gain are 6.4 dB obtained with wide bandwidth range of (27.4-28.7) GHz. This proving to increase the realized gain by implementing SIW at millimeter wave band for 5G application network.
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Can AI do good? at 'offtheCanvas' India HCI preludeAlan Dix
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1. Progress In Electromagnetics Research B, Vol. 7, 173–189, 2008
AN OVERVIEW ON DEFECTED GROUND
STRUCTURE
L. H. Weng, Y. C. Guo, X. W. Shi, and X. Q. Chen
National Key Laboratory of Antenna and Microwave Technology
Xidian University
NO. 2 South Taibai Road, Xi’an, Shaanxi, P. R. China
Abstract—This paper focuses on a tutorial overview of defected
ground structure (DGS). The basic conceptions and transmission
characteristics of DGS are introduced and the equivalent circuit models
of varieties of DGS units are also presented. Finally, the main
applications of DGS in microwave technology field are summarized
and the evolution trend of DGS is given.
1. INTRODUCTION
High performance, compact size and low cost often meet the stringent
requirements of modern microwave communication systems. There
have been some new technologies such as Low-temperature co-fire
ceramic technology (LTCC), Low-temperature co-fire ferrite (LTCF)
and some new structures such as Photonic band gap (PBG), DGS,
Substrate integrate wave-guide (SIW) and so on to enhance the whole
quality of system. In 1987, Yablonovitch and John proposed PBG [1, 2]
which implodes and utilizes metallic ground plane, and breaks
traditional microwave circuit confined design to surface components
and distributions of the medium circuit plane. Consequently, there
has been an increasing interest in microwave and millimeter-wave
applications of PBG [3–7]. Similarly, there is another new ground plane
aperture (GPA) technique which simply incorporates the microstrip
line with a centered slot at the ground plane, and the use of GPA
has attractive applications in 3 dB edge coupler for tight coupling
and band pass filters for spurious band suppression and enhanced
coupling [8, 9, 10].
PBG is a periodic structure which has been known as providing
rejection of certain frequency band. However, it is difficult to use
a PBG structure for the design of the microwave or millimeter-wave
2. 174 Weng et al.
components due to the difficulties of modeling. There are so many
design parameters that effect on the band gap property, such as the
number of lattice, lattice shapes, lattice spacing and relative volume
fraction. Another problem is caused by the radiation from the periodic
etched defects. Furthermore, with the introduction of a GPA below
the strip, the line properties could be changed significantly as the
characteristic impedance varies with the width of the GPA. Usually
the GPA is considered as the basis of equivalent J-inverter circuit
theory and its filtering behavior has been characterized by a closed-form
equation. As a technique to improve circuit performance, there
is more investigations on the applications than the essence of GPA. In
order to alleviate these problems Park et al. [11] proposed DGS which
is designed by connecting two square PBG cells with a thin slot. DGS
which bases on GPA focuses not only on its application but also on its
own characteristics. DGS adds an extra degree of freedom in microwave
circuit design and opens the door to a wide range of application. In
the following years, a great lot of novel DGSs were proposed and they
had become one of the most interesting areas of research owing to
their extensive applicability in microwave circuits. The parameters of
equivalent circuits models of DGSs were also researched and utilized
to design planar circuit easily. Many passive and active microwave and
millimeter devices have been developed to suppress the harmonics and
realize the compact physical dimensions of circuits for the design flow
of circuits with DGS comparatively simple.
In this paper, a tutorial overview of DGS is present.The
basic conception and transmission characteristics of DGS units are
introduced and the equivalent circuit models of varieties of DGS units
are also presented. Finally, the main applications of DGS in microwave
technology field are summarized and the evolution trend of DGS is
given.
2. DEFECTED GROUND STRUCTURE
DGS is an etched periodic or non-periodic cascaded configuration
defect in ground of a planar transmission line (e.g., microstrip, coplanar
and conductor backed coplanar wave guide) which disturbs the shield
current distribution in the ground plane cause of the defect in the
ground. This disturbance will change characteristics of a transmission
line such as line capacitance and inductance. In a word, any defect
etched in the ground plane of the microstrip can give rise to increasing
effective capacitance and inductance.
3. Progress In Electromagnetics Research B, Vol. 7, 2008 175
Figure 1. The first DGS unit: (a) Dumbbell DGS unit, (b) Simulated
S-parameters for dumbbell DGS unit.
2.1. Basic Structure and Transmission Characteristics
The dumbbell DGS are composed of two a × b rectangular defected
areas, g × w gaps and a narrow connecting slot wide etched areas in
backside metallic ground plane as shown in Fig. 1(a). This is the first
DGS [11]. Fig. 1(b) shows the S-parameters from an EM simulation
of a dumbbell DGS. DGSs have the characteristics of stopband,
slow-wave effect and high impedance. DGS has more advantages
than PBG as follows: (1) The circuit area becomes relatively small
without periodic structures because only a few DGS elements have the
similar typical properties as the periodic structure like the stop-band
characteristic. (2) The simulated S-parameters for dumbbell DGS unit
can be matched to the one-pole Butterworth-type low-pass response.
For the DGS unit, DGS pattern is simply fabricated and its equivalent
circuit is easily extracted. (3) DGS needs less circuit sizes for only a
unit or a few periodic structures showing slow-wave effect. Compared
with PBG, DGS is more easily to be designed and implemented and
has higher precision with regular defect structures. Therefore, it is
very extensive to extend its practical application to microwave circuits.
DGS has more competition than PBG in the microwave circuit with
high requirement of dimension under certain craftwork conditions.
2.2. DGS Unit
There have been two research aspects for adequately utilizing the
unique performance of DGS: DGS unit and periodic DGS. A variety of
4. 176 Weng et al.
slot geometries etched in the microstrip line ground plane have been
reported in the literature [12–16]. In Fig. 2, it is shown that a variety
of attached area shapes including spiral head, arrowhead-slot and “H”
shape slots and so on. There also have been more complex DGSs
so as to improve the circuit performance shown in Fig. 2, such as: a
square open-loop with a slot in middle section, open-loop dumbbell and
interdigital DGS. The new DGS unit could control the two transmission
zeros near the passband edges and easily control the frequency of the
slot by changing the length of the metal fingers [17, 18].
Figure 2. Various DGSs: (a) spiral head, (b) arrowhead-slot, (c) “H”
shape slots, (d) a square open-loop with a slot in middle section , (e)
open-loop dumbbell and (f) interdigital DGS.
The use of a bent microstrip line does not significantly change the
frequency behavior that remains as for the straight DGS microstrip
line. The bending technique leads to a 2D configuration, in which the
microstrip line presents multiple bends, following a similar structure
as that of a meander line. This configuration has a broad stopband
and allows a large number of periods in a reasonable circuit area. New
proposed DGS unit has some advantages than dumbbell DGS:
(1) A higher slow wave factor and more compact circuit. The circuit
area of filter using “H” shape slots is much smaller about 26.3%
than using dumbbell DGS [19].
(2) A narrow width stopband and deeper rejection.
(3) A slightly larger external Q. To compare the transfer character-istics
of the U-slot DGS with that of the conventional DGS, the
spiral-shaped DGS and U-slot DGS are designed to provide the
same resonance frequency. Q factor of the spiral DGS is 7.478
(3 dB bandwidth of 0.39 GHz), while the U-slot DGS provides a
high-Q factor of 36.05 (3 dB bandwidth is 0.081 GHz) [20].
In a word, more and more new DGSs are proposed which bring a
great convenience to the design of microwave circuit to realize various
passive and active device compact structures and to suppress the
harmonics.
5. Progress In Electromagnetics Research B, Vol. 7, 2008 177
2.3. Periodic DGS
Periodic structures such as PBG and DGS for planar transmission
lines have drawn a wide interest for their extensive applicabilities in
antennas and microwave circuits. Transmission lines with a periodic
structure have a finite pass and rejection band as low-pass filters. The
increased slow-wave effect and the additional equivalent components
are important properties of periodic structure that can be realized
and the circuit sizes can be reduced using these properties. Periodic
means repetition of the physics structure. By cascading DGS resonant
cells in the ground plane the depth and bandwidth of the stopband
for the proposed DGS circuit are inclined to depend on the number
of period. Period DGSs care about parameters including the shape
of unit DGS, distance between two DGS units and the distribution of
the different DGSs. As shown in Fig. 3, by now there are two types
of periodic DGS: one is (a) horizontally periodic DGS(HPDGS), the
other is (b)vertically periodic DGS(VPDGS) [21–23].
(a) (b)
Figure 3. Periodic DGS: (a) HPDGS, (b) VPDGS.
The prominent feature of the proposed structure is possible to
organize the periodicity along the vertical direction as well as the
horizontal direction. It is named as VPDGS. On the other hand, the
conventional DGS for planar transmission lines have the only HPDGS
with serially cascading structure along the transmission direction.
HPDGS initially is produced for enlarging the stopband of frequency
response curve. Few uniform square-patterned defects form a periodic
DGS for planar circuit, which provides excellent stopband and slow-wave
characteristics. They have been reported and used in oscillators
and amplifiers [23–26]. Nonuniform circular-patterned DGSs using
the function distribution compared with the previous periodic DGSs
are proposed. They have a compensated microstrip line and the
6. 178 Weng et al.
dimensions of the square defects are varied proportionally to relative
amplitudes distribution of the exponential function e1/n distribution (n
denotes the positive integer), or Chebyshev, [ln (10)]1/n distribution,
C1/n distribution and so on. VPDGS produces much higher slow-wave
factor than HPDGS. The increased slow-wave factor means the
longer electrical length for the same physical length. As an application
example, a size-reduced amplifier was designed by inserting VPDGS
into the matching network. Two series microstrip lines in input and
output matching networks of the amplifier were reduced to 38.5% and
44.4% of the original lengths, respectively [22].
3. EQUIVALENT CIRCUITS OF DGS
Design and analysis are two challenges for DGS. The commercially
available EM solvers is the main resource to design and analyze DGS.
To apply the proposed DGS section to a practical circuit design
example, it is necessary to extract the equivalent circuit parameters.
In order to derive the equivalent circuit parameters of DGS unit at the
reference plane, the S-parameters vs.frequency should be calculated
by full-wave electromagnetic (EM)-simulation to explain the cutoff
and attenuation pole characterstics of the DGS section. The circuit
parameters for the derived equivalent circuit can be extracted from the
simulation result which can be fit for the one-pole Butterworth-type
low-pass response. The full-wave analysis does not give any physical
insight of the operating principle of DGS. The follow flow chart in
Fig. 4 shows the conventional design and analysis methods of DGSs.
The full-wave solver is used to find the S-parameters vs. frequency
behavior of the DGS. The disadvantage of this method is that there is
no direct correlation between the physical dimensions of DGS and the
equivalent LC parameters. The derived performance of DGS is not
fully predictable until the optimized solutions are achieved through
trial and error iterative process. Hence the conventional methods as
reported in the open literature [11, 27–31, 36] are time consuming and
may not lead to optimum design.
At present, DGS can be equivalent by three types of equivalent
circuits: (1) LC and RLC equivalent circuits, (2) π shaped equivalent
circuit, (3) quasi-static equivalent circuit.
3.1. LC and RLC Equivalent Circuits
The equivalent circuit of the DGS and one-pole Butterworth prototype
of the LPF are given in Fig. 5. The rectangular parts of dumbbell
DGS increase route length of current and the effective inductance.
7. Progress In Electromagnetics Research B, Vol. 7, 2008 179
Figure 4. Conventional design and analysis method of dumbbell DGS.
The slot part accumulates charge and increases the effective capacitor
of the microstrip line. Two rectangular defected areas and one
connecting slot correspond to the equivalently added inductance (L)
and capacitance (C), respectively. Accordingly, a resonance occurs at
a certain frequency because of the parallel L-C circuit. Inversely, it is
intuitively known that the equivalent circuit includes a pair of parallel
inductor-capacitor form the resonant phenomenon in the S-parameter.
As the etched area of the unit lattice increases, the effective series
inductance increase and increasing the series inductance gives rise to
a lower cutoff frequency. When the etched gap distance increases, the
effective capacitance decreases so that the attenuation pole location
moves up to higher frequency.
(a) (b)
Figure 5. LC equivalent circuit: (a) equivalent circuit of the dumbbell
DGS circuit, (b) Butterworth-type one-pole prototype low-pass filter
circuit.
8. 180 Weng et al.
In order to match DGS to Butterworth low-pass filter reactance
values of both circuits are equal at the cutoff frequency. So L and C
are derived as follows:
XLC =
1
ω0C
ω0
ω
− ω
ω0
(1)
where, ω0 is the resonance angular frequency of the parallel LC
resonator.
C = ωc
Z0g1
· 1
ω2
0
− ω2
c
L = 1/4π2f2
0C
(2)
where f0 and fc are resonance (attenuation pole) and cutoff frequency
which can be obtained from EM simulation results. The characteristics
of most of DGS are similar to dumbbell DGS, so they could be discussed
by one-pole Butterworth low-pass filter too. Furthermore, radiation
effects are more or less neglected. DGS unit can be modeled most
efficiently by a parallel R, L, and C resonant circuit connected to
transmission liens at its both sides as shown in Fig. 6. This resistance
corresponds to the radiation, conductor and dielectric losses in the
defect. From EM simulations or measurements for a given DGS, the
equivalent R, L, and C values are obtained from the expression in [27].
Figure 6. RLC equivalent circuit for unit DGS.
C = ωc
2Z0
ω2
0
− ω2
c
L = 1/
4π2f2
0C
R(ω) = 2Z0
1
|S11(ω)|2
−
2Z0
ωC − 1
ωL
2
− 1
(3)
9. Progress In Electromagnetics Research B, Vol. 7, 2008 181
The size of DGS is determined by accurate curve-fitting results
for equivalent-circuit elements to correspond exactly to the required
inductance.
3.2. π Shaped Equivalent Circuits
However, it is very difficult to implement the DGS circuits for the
purposed of the harmonic termination to satisfy simultaneously the
excellent pass band and stop band characteristics. More accurate
equivalent circuit models than the LC and RLC equivalent circuit
were proposed, such as π shaped equivalent circuit shown in Fig. 7.
(a) (b)
Figure 7. π shaped equivalent circuit for unit DGS: (a) equivalent
circuit, (b) π shaped circuit.
Considered the phase influence of DGS, Park proposed π shaped
equivalent which simulates both amplitude vs. frequency and phase vs.
frequency characteristics. The S-parameters vs. frequency curve of π
shaped equivalent is more anatomized than LC and RLC equivalents,
but its circuit is more complex and the parameters is so many that
the equivalent is difficult to extract. π shaped equivalent circuit is
much suitable to the exigent precision of circuit design. The ABCD
parameters for the unit cell will be obtained using the expression as
follows:
11. 1 + Yb/Ya 1/Ya
2Yb + Y 2
b /Ya 1 + Yb/Ya
(4)
Ya = 1/Rg + jBr
Yb = 1/Rp + jBp
Cg = Br
ω2
ω1
ω2
− ω2
ω1
, Lg =
1
ω2
2Cg
, Cp = Bp
ω1
(5)
The full-wave analysis is very involving and does not give any physical
insight of the operating principle of the DGS.
12. 182 Weng et al.
3.3. Quasi-static Equivalent Circuit
Different from the two types of equivalent circuits mentioned above, a
quasi-static equivalent circuit model of a dumbbell DGS is developed
which is directly derived from the physical dimensions of dumbbell
DGS is depicted in Fig. 8.
(a) (b)
Figure 8. New design and analysis method of DGS: (a) analysis
method of DGS, (b) equivalent-circuit model of unit cell DGS.
This overcomes the limitation of report full-wave analysis by
developing the equivalent circuit model. This approach gives
a comprehensive understanding of the physical principle of DGS
including how the DGS creates bandstop and bandpass responses
and which dimensions play the most vital role to create the distinct
performance. At present, the equivalent circuits are mostly concerned
about influences of the addition of DGS such as radiation, or an
equivalent circuit corresponded to a new DGS. Because different DGS
has different characteristic, different equivalent circuits are not formed
uniform circuit model and mathematics theory for the moment. Thus,
the optimization based on an equivalent circuit network is highly
desirable to design and evolve this kind of circuit configuration.
13. Progress In Electromagnetics Research B, Vol. 7, 2008 183
4. APPLICATION IN MICROWAVE CIRCUIT
There are widely applications in active and passive devices useful
for compact design. Since each DGS provides its own distinctive
characteristics depending on the geometries, such circuit functionalities
as filtering unwanted signals and tuning high-order harmonics can
easily be accomplished by means of placing required DGS patterns,
which correspond to the desired circuit operations without increasing
circuit complexity.
4.1. Stopband Effects
DGS, which is realized by etching off a defected pattern or periodic
sturctures from the backside metallic ground plane, has been known
as providing rejection of certain frequency band, namely, bandgap
effects. The stopband is useful to suppress the unwanted surface waves,
spurious and leakage transmission. Therefore, a direct application of
such frequency selective characteristics in microwave filters is becoming
a hotspot research recently. As Fig. 9 shown, the Hilbert curve ring
(HCR) DGS lowpass filter achieves a quite steep rejection property,
a low in-band insertion less of below 0.5 dB and a high outband
suppression of more than 33 dB in a wide frequency rang [33].
(a) (b)
Figure 9. HCR DGS lowpass filter (a) layout of the HCR DGS lowpass
filter (3-cell), (b) simulation and measurement results.
DGS provides excellent performances in terms of ripples in the
passband, sharp-selectivity at the cut-off frequency and spurious free
wide stopband. There have two types of filter design using DGS: one is
directly using the frequency-selectivity chrematistic of DGS to design
filters [31–34], the other is using DGS on the conventional microstrip
14. 184 Weng et al.
filters so as to improve performance [35–39]. The second search
concerns exploitation both on the conductor plane of the microstrip
and the ground plane which is the most investigation hotspot in recent
years. Several improvements are obtained using DGS in the metallic
ground plane for the response of filter. These improvements summarize
as follows: (1) More transition sharpness, (2) Suppressing higher
harmonic, (3) Achieving broader stopband responses, (4) Improving
the stopband and passband characteristics. Some DGS also tries
to combine new material and new technology to design filters. For
example, a filter is designed based on DGS and LTCC [40]. There also
adopts SIW combined with the concept of DGS [41].
4.2. Slow-Wave Effect
One of the most important advantages of DGS is the slow-wave effect
which is caused by the equivalent LC components. The transmission
lines with DGS have much higher impedance and increased slow-wave
factor than conventional lines. So the circuit size can be reduced
with these properties, such as microwave amplifiers and Rat-race
hybrid couplers [42]. Furthermore, DGS could be used in broadband
couplers. In Fig. 10, DGS Doherty power amplifier (DDA) could
reduce the circuit size effectively by the negligible insertion loss,
excellent harmonic termination characteristic and slow-wave effect [43].
Compared with the conventional Doherty power amplifier (CDA), the
radios of the reduced lengths to CDA are 71% at the carrier amplifier
output and 62% at the peaking amplifier output. Another attractive
application of the DGSs is in the beam steering of a phased array
antenna. DGS also can improve the performance of the antenna,
restrain harmonious and reduce the mutual coupling of antenna array
by suppressing the surface waves [44, 45].
Figure 10. Comparison of the whole circuit size of CDA and DDA.
4.3. High Characteristic Impedance
It is a serious problem for conventional microstrip line case that the
generally accepted impedance is limited to realize is around 100 ∼
15. Progress In Electromagnetics Research B, Vol. 7, 2008 185
Figure 11. Photo of the fabricated 1:6 Wikinson divider with DGS.
130 Ω. By adopting DGS on the ground plane is possible to increase
the equivalent inductance L highly, and to decrease the equivalent C at
the same time, and finally to raise the impedance of the microstrip line
more than 200 Ω. For example, Fig. 11 shows layout of the proposed
1:6 unequal Wilkinson power divider that has been designed adopting
DGS and a microstrip line with 208Ω of characteristic impedance has
been realized using a simple rectangular-shaped DGS [46]. The high
characteristic impedance of DGS may also be used in digital systems
(interconnects).
5. CONCLUSIONS
In this paper, the evolutions of DGS from conventional PBGs are
reported. The basic conceptions and transmission characteristics of
DGS are introduced and the equivalent circuit models of varieties of
DGS units are also presented. DGS has simple structure, equivalent
LC circuit model, and potentially great applicability to design RF
circuit. Various designs in HMIC and MMIC have been investigated
to yield better performance in terms of passband width, ripple free
transmission and wider stopband.
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