Search

This study is established for designing an Equilateral Triangular Microstrip Patch Antenna (ETMPA) operating at 28GHz suitable for 5G application technologies. The design procedure is performed by considering inset fed techniques and implementing both Computer Simulation Technology (CST) and High Frequency Simulator Structure (HFSS) in order to assess their performance through the computation of antenna parameters. In order to arrive at the aforementioned objectives, different substrate materials with different heights and various conductor patch material types are utilized and their effect on the antenna radiation performance is investigated. The simulation results reveal that a minimum low-profile (ETMPA) of the order of (4.59 mm3) with reliable radiation performances is generally achieved by Taconic-TLX-9 dielectric substrates of height (h=0.2mm) and with copper patch material. Based on the specifications provided above, the results show that the S11, VSWR, efficiency, directivity, gain and bandwidth with both CST and HFSS techniques are, respectively, (-26.24, -14.60), (1.102, 1.53), (81%, 87.6%), (6.31, 6.52) dB, (5.39, 5.94) dB and (0.708 GHz, 0.503 GHz). Besides, a good agreement between the presented optimum antenna parameters is also observed as compared to the ones previously obtained experimentally or theoretically by other researchers for different patch shapes operating at 28 GHz. In addition, the computed results of the antenna parameters display generally that the CST provides better results than HFSS as compared to the ones experimentally obtained by previous researchers. Finally, the proposed antenna design has the advantage of size reduction in comparison to most of the other works and it is one of the 5G technology requirements. [ABSTRACT FROM AUTHOR]

When using Gaussian process (GP) machine learning as a surrogate model combined with the global optimization method for rapid optimization design of electromagnetic problems, a large number of covariance calculations are required, resulting in a calculation volume which is cube of the number of samples and low efficiency. In order to solve this problem, this study constructs a deep GP (DGP) model by using the structural form of convolutional neural network (CNN) and combining it with GP. In this network, GP is used to replace the fully connected layer of the CNN, the convolutional layer and the pooling layer of the CNN are used to reduce the dimension of the input parameters and GP is used to predict output, while particle swarm optimization (PSO) is used algorithm to optimize network structure parameters. The modeling method proposed in this paper can compress the dimensions of the problem to reduce the demand of training samples and effectively improve the modeling efficiency while ensuring the modeling accuracy. In our study, we used the proposed modeling method to optimize the design of a multiband microstrip antenna (MSA) for mobile terminals and obtained good optimization results. The optimized antenna can work in the frequency range of 0.69–0.96 GHz and 1.7–2.76 GHz, covering the wireless LTE 700, GSM 850, GSM 900, DCS 1800, PCS1900, UMTS 2100, LTE 2300, and LTE 2500 frequency bands. It is shown that the DGP network model proposed in this paper can replace the electromagnetic simulation software in the optimization process, so as to reduce the time required for optimization while ensuring the design accuracy. [ABSTRACT FROM AUTHOR]

In this paper, an approach for teaching basic antenna theory and propagation to senior level undergraduate students for electrical engineering related fields is proposed and described. The method combines mathematical and theoretical studies with antenna design and laboratory measurements to reinforce the subject's theoretical and practical aspects together. Topics discussed in lectures include performing antenna radiation calculations, learning how to make antenna radiation pattern measurements, and designing of antennas such as microstrip patch antenna. The education is based on teaching these principles and enabling students to make some antenna measurements. At the end of the semester, an analysis on learning outcomes of the course was performed and feedback from students was taken. The feedback from students showed that there was a huge satisfaction in terms of achieving the goals in learning outcomes. The course structure proposed can be a good example for instructors who teach antennas and propagation courses. [ABSTRACT FROM AUTHOR]

The increasing applications for nomadic computing have experienced enormous development over the preceding decade. This has eventually caused the lack of bandwidth. Therefore, to accomplish the need of consumers, compact antennas shall be designed for mmWave wireless communications. Consequently, this paper presents a novel negative meander line based microstrip antenna system being composed of inductors (L) and capacitors (C). A detailed impedance analysis of the configuration is reported. The effects of changing the radiating element's width and length on the resonant frequency have been studied. The finalized arrangement involved 243 sq. mm area and functioned at 28 GHz with a bandwidth of 2.16 GHz. At resonant frequency, the system exhibited gain and efficiency values of 8.40 dBi and 83.51%, respectively. Furthermore, the proposed design demonstrated better bandwidth and gain capabilities in comparison with the conventional microstrip patch antenna and meander line antenna. [ABSTRACT FROM AUTHOR]

A design of two microstrip antennas with improved isolation and reduction of mutual coupling between them using metamaterial structure is introduced. The technique which is used to reduce the coupling is complementary split ring resonator (CSRR) loaded between the two microstrip patches. The proposed antenna is designed to operate at frequency of 28GHz. This structure is suitable to operate in 5G and mm-wave antenna systems. A significant improvement in coupling between antennas using metamaterial structure is obtained compared to EBG structures at the same frequency. The maximum isolation achieved by etching the CSRR on the ground of the proposed antenna and on a floated ground between the two patched is 36.2 dB. The distance from edgeto- edge of the patch antennas is 0.4λ0. In addition to design and simulate the proposed antenna using CST program, it is also fabricated and measured. Good agreement is achieved between simulated and measured results. [ABSTRACT FROM AUTHOR]

In this study, a method was proposed to develop a compact antenna for a drone-borne synthetic aperture radar(SAR). The compact antenna structure was designed as a microstrip patch antenna, and a parasitic patch was stacked on the radiation patch to improve the bandwidth and gain of the antenna. The size and interval between patches were iteratively adjusted based on the simulation in order to satisfy the requirements of the antenna. Additionally, HH-, VV-, HV-, and VH-polarimetric antennas were fabricated to acquire fully polarimetric SAR data. As a result, the compact antenna could be successfully developed with a small weight of less than 100 grams. [ABSTRACT FROM AUTHOR]

The microstrip antenna is designed for the measurement of soil moisture content for agriculture applications. In this paper, the single and dual-band microstrip antennas are designed, simulated and fabricated. The simulated results are compared and analysed with measured results for both designed for different types of feeds. It is found that the simulated and measured results are similar and better. Therefore, the fabricated antennas can be used for the soil moisture content measurement for agriculture applications. The dual resonant frequency antennas results are better than the single band antenna, it covers wide band thus, and it can be applied for wide applications. [ABSTRACT FROM AUTHOR]

In this paper, a microstrip patch antenna (MPA) design was developed to verify the performance of a metamaterial cell array (MTM) Capacitive Loaded Loop (CLL) immersed in the substrate. The metamaterial was obtained from metal laminates designed inside a dielectric material, with dimensions carefully calculated to have the effective negative permittivity and permeability, consequently the negative refractive index, in a certain frequency range. In this case, the geometric control of the unit cell parameters allowed its organization in a periodic arrangement to be immersed in the MPA substrate. Simulated and experimental results were obtained and compared for some parameters of the antenna, which showed a good relationship between MTM and MPA performance. [ABSTRACT FROM AUTHOR]

Parametric study and analysis of microstrip patch antenna with multiple slit positions is presented in this research contribution. This work is aimed to design a microstrip patch antenna, which can able resonate dual-band frequencies (i.e. 3.5 GHz and 5.3 GHz) with a trade-off between the geometrical parameters. The proposed antenna designed using the multiple slits on the patch, RT Duroid 5880 as substrate material, and with a defected ground structure. Owing to the geometrical miniaturization this antenna will be capable to work at sophisticated communication systems where size of the communication system is a desired parameter. [ABSTRACT FROM AUTHOR]

Summary: In this paper, a novel multiple slot loading technique is studied in detail for the isolation enhancement of the dual‐band MIMO antenna system. The proposed MIMO antenna design consists of the microstrip patch loaded with T‐shaped slots parallel to the non‐radiating edge of the patch. The frequency tuning could be achieved by varying the length of the T‐shape slot arm. The proposed MIMO antenna system is optimised for operation in WLAN and WiMAX applications. The isolation enhancement is achieved by providing simple multiple slots loaded in the ground plane between radiating elements. The length of the slots is λ/4. The system is fabricated and tested using a vector network analyser and anechoic chamber. The reduction in mutual coupling up to −29.16 dB and −24.09 dB for the 2.4 GHz and 3.4 GHz, respectively, is achieved. The bandwidths are 62.3 MHz (3.33–3.39 GHz) and 55.5 MHz (2.37–2.42 GHz), respectively. The total gain obtained in this case is 1.8 dBi at 2.4 GHz and 1.2 dBi at 3.4 GHz, respectively. The dimensions of the proposed designed antenna are 70 mm × 60 mm × 1.6 mm. The results were also verified through mutual coupling parameters like envelope correlation coefficient (ECC) and channel capacity loss (CCL) at the desired frequencies. [ABSTRACT FROM AUTHOR]

The paper presents a review on antenna designing and fabrication techniques with Microstrip Patch (MSP) development. The requirements of MSP are remote controlling, mobile communication, space communication and all wireless communication areas. Aim of this development is to provide a new approach of the designing and simulation of circular MSP for 5.8 GHz operating frequency. CST MICROWAVE STUDIO (MWS) facilitates the quick and accurate analysis of high frequency (HF) antennas which gives the responses and results before fabrication of actual patch with complete technology for 3D EM. FR-4 glass epoxy material board is used for fabrication which is admired and adaptable high pressure thermoset plastic laminate grade with superior strength to weight ratios. Circular MSP is easy to fabricate, portable, lightweight and low cost antenna. N9923A Field Fox RF VNA (Vector Network Analyser) were used for studying and testing all the parameters of fabricated MSP. [ABSTRACT FROM AUTHOR]

The antenna simulation is generally done manually where certain antenna parameters are changed by trial and error method until the desired performance is obtained. In this study, the E-shaped microstrip antenna was designed to work in wideband frequency using the Particle Swarm Optimization (PSO) algorithm. The E-shaped patch antenna with ground follows the subtraction size. The type of substrate used in this study is FR4 Epoxy with a relative dielectric constant value (r) = 4.6 and thickness (h) = 1.6 mm. Feeding technique used in the connector is a probe feed technique to get matching impedance that matches the impedance of the connector which is 50 ohms. The working frequency of the E-shaped microstrip antenna after the use of the PSO algorithm generated bandwidth of 295 MHz with a working frequency of 340-635 MHz. From several stages of optimization performed, an ideal gain is obtained in accordance with the characteristics of the E-shaped antenna, where the resulting gain is 3.246 dBi. The characteristic obtained is omnidirectional, where the donut-shaped radiation pattern with the direction of the wave is in all directions. [ABSTRACT FROM AUTHOR]

In this study, a coplanar waveguide-fed compact microstrip antenna design for applications operating at higher 5G bands was proposed. The antenna with the compact size of 8 x 12.2 mm2 on FR4 substrate, having the dielectric constant of 4.3 and the height of 1.55 mm, was considered. The dimensions of the radiating patch and ground plane were optimized with the use of artificial cooperative search (ACS) algorithm to provide the desired return loss performance of the designed antenna. The performance analysis was done by using full-wave electromagnetic package programs based on the method of moment (MoM) and the finite integration technique (FIT). The 10 dB bandwidth for return loss results obtained with the use of the computation methods show that the proposed antenna performs well for 5G applications operating in the 24.25 - 27.50 GHz, 26.50 - 29.50 GHz, 27.50 - 28.35 GHz and 37 - 40 GHz frequency bands. [ABSTRACT FROM AUTHOR]

This paper presents a new design of the microstrip patch antenna operated at the terahertz frequencies (700-850 GHz). The conventional microstrip patch antenna dimensions shrink to a few microns when operating at such terahertz frequencies. Thus, the design of the patch and its feeding network will be miniaturized extremely, and their fabrications would be extremely difficult. In this paper, the configuration of the proposed microstrip patch antenna is suited in a way that it can be modelled using multilayers structure. This multilayer structure facilitates the modeling, and considering its fabrication. The proposed microstrip antenna has been designed using three layers. The top layer is used to model the rectangular patch; while the second layer is for the substrate, and the bottom layer is for the ground plane. The physical dimensions of the layers and the fed-line are optimised using the microwave Computer Simulation Technology (CST) simulator in order to enhance the electrical parameters of the antenna such as antenna realised gain, bandwidth, total and radiation efficiencies, and radiation patterns. In addition to that, the impact of the physical dimensions of the rectangular patch on controlling the resonant frequency of the dominant mode (TM01) have been investigated. Keeping the lower and higher propagating modes out of the frequency band of interest is another aspect which has been addressed in this paper. The antenna has been simulated, and its realised gain fluctuates from 6.4 dBi to 9.7 dBi over the operating frequency range (700-850 GHz). Also, it provides extremely large reflection coefficient bandwidth (S11) which it is below -10 dB over the entire operating frequency band. The total efficiency is more than 75 %. Due to its simplicity and providing large bandwidth, the proposed antenna could be of interest in many security and surveillance applications. [ABSTRACT FROM AUTHOR]

In this paper the effect of silver coating on the performance of microstrip antenna array is examined. The conventional four element microstrip antenna array is producing narrow bandwidth of 4.89% and high values of mutual coupling of -16.95, -14.22 and - 17.30 dB respectively. The modified microstrip antenna array is producing enhanced bandwidth of 31.43% and reduced mutual coupling of -29.45, -32.71 and -29.94 dB respectively. In addition, good amount of reduction in backward power and increase of forward power indicate improved performance of modified microstrip antenna array. The microstrip antenna arrays are designed using Mentor Graphics IE3D software. The thickness of silver deposition is equal to 30 nm. The conventional microstrip antenna array designed at 6 GHz is resonating at 5.53 GHz with a return loss of -21.12 dB. The dielectric substrate used to design and fabricate microstrip antenna arrays is FR-4 glass epoxy. The measured results of the fabricated antenna arrays are obtained using vector network analyzer. [ABSTRACT FROM AUTHOR]

This paper is presenting two different microstrip antennas (LHCP and RHCP antennas). It can explain the effects of S-shape and Z-shape slots for left-hand circular polarization and right-hand circular polarization respectively. Both types of slots are used to convert linear polarized antenna into the circularly polarized antenna. It is simulated with the help of CST-2015 and HFSS2018 design software. The antenna is designed into two steps. At first step, a simple linear microstrip antenna is designed and with second step, slots are used for circular polarization. The operating simulated frequency in both types of software's is 0.258 THz to 0.355 THz and having 11 % operating bandwidth with the axial ratio at 3 dB. All the results of both antennas are the same but only radiation patterns results are opposite in polarization. The paper also presents the parametric study of copper material thickness and substrate thickness of the antenna. [ABSTRACT FROM AUTHOR]

Proximity fed wideband and high gain designs of rectangular microstrip antennas gapcoupled with parasitic rectangular and H shape patches are proposed. In the L frequency band, optimum response with bandwidth of more than 60% and peak gain of 9.9 dBi is obtained for rectangular microstrip antenna with eight gapcoupled rectangular shape patches. Further gapcoupled configurations of H shape patches with rectangular patch is presented. This design provides bandwidth of above 950 MHz (65%) with peak gain of more than 9.5 dBi. The comparison for the proposed gap-coupled rectangular and H shape variations with reported antennas is presented. In the proposed gap-coupled designs, asymmetric placement of parasitic patches with respect to fed patch yields focused radiation in the one side of antenna which results in overall bandwidth and gain enhancement. [ABSTRACT FROM AUTHOR]

A dual‐band dual‐mode microstrip Yagi antenna with quasi‐end‐fire radiation patterns is proposed in this paper. It consists of five radiating patches driven by a single slot‐loaded patch placed in the middle. Meanwhile, two slot‐loaded parasitic patches are symmetrically located on two sides of the driven patch, respectively. In the lower band, the five patches involved resonate at TM01 mode. While in the upper band, all the patches resonate at TM02 mode. In order to ensure quasi‐end‐fire radiations in the both bands, four slots are symmetrically etched around the strongest surface currents of each patch resonating at TM02 mode. As a result, the resonant frequency of TM02 mode is decreased dramatically, while the resonant frequency of TM01 mode almost remains unchanged. With these arrangements, the separations between any two of the adjacent patches at their centers satisfy the requirements in design of the microstrip Yagi antenna in both bands, so as to realize the dual‐band dual‐mode microstrip Yagi antenna on a single‐layer substrate. Finally, an antenna prototype is fabricated and tested. The measured results reveal that the dual operating bands of 2.76~2.88 and 4.88~5.03 GHz for |S11| < −10 dB are satisfactorily achieved. Most importantly, the proposed antenna can indeed realize the quasi‐end‐fire radiation patterns in dual operating bands. [ABSTRACT FROM AUTHOR]

A compact four-element MIMO microstrip antenna is designed, analyzed and proposed for high frequency modern wireless applications. Proposed antenna is compact in size and offers a frequency band of about 6 GHz ranging from 23 to 29 GHz with a peak gain of 7.1 dBi and suppressed mutual coupling and cross-polarization level. Presented antenna possess better diversity with minimum mutual coupling among its all four elements. Diversity is verified in terms of envelope correlation coefficient, directive gain, total active reflection coefficient and ratio of mean effective gain. All the diversity parameters are found within the appropriate limit standardized for a MIMO device. Experimental results of fabricated prototypes verified the proposed results. [ABSTRACT FROM AUTHOR]

A dual‐band dual‐mode microstrip antenna design is presented, with the application of adaptive interference cancellation in global positioning system at the L1 and L2 bands. The antenna consists of two stacked TM11 rings and two stacked TM21 shorted rings all fed by coaxial probes. By properly combining the two modes and utilizing both polarization components of each mode, up to three nulls can be steered at each frequency band to cancel interferers close to horizon. The concentric structure of the radiating patches in the proposed design allows for a compact antenna, which for a substrate of dielectric constant of 10 is only 0.33 λ in diameter at its lowest frequency of operation and can be further miniaturized on a higher dielectric constant substrate. [ABSTRACT FROM AUTHOR]

This paper present transparent, all dielectric water-based metamaterial (MM) superstrates with reconfigurable characteristics is employed for gain and bandwidth enhancement of a water-based microstrip patch antenna. The water-based microstrip patch antenna is fed by an L-shape probe. All dielectric water-based MM unit-cell element consists of dielectric cubic boxes filled with water is designed and analyzed. The reconfigurable electric properties are achieved via changing the water height in the MM unit-cell element. Different arrangements of the MM array with water height tapering are optimized and designed for microstrip patch antenna gain enhancement. The MM array is used as a single layer superstrate placed normal to the microstrip patch. A water-based MM lens consists of three layers is designed to collimate the radiation from the microstrip patch antenna. The phase compensation in the MM lens is achieved via changing the water height in the MM unit-cell elements of the lens. A reconfigurable beam in different directions from −30° to +30° is steered by changing the water level distribution over the MM lens unit-cell elements. A full-wave analysis using the finite integration technique is used for the design and analysis of the water-based MM lens arrangements. [ABSTRACT FROM AUTHOR]

A conformal circularly polarized (CP) series-fed microstrip array design for broadside radiation is presented. The array aperture under design is conformal to a cylindrical surface of a given radius. The approach we present primarily addresses focusing of the CP major lobe of the conformal array by proper dimensioning of the aperture spacings. The proposed analytical models yield the values of the element spacings within the series-fed conformal array aperture and element-specific spacings of the patch radiators within each CP element. These spacings are critical to produce a broadside CP major lobe at the design frequency. Subsequently, each array element is equipped with an in-line matching quarter wave transformer. The measured characteristics of the ${X}$ -band conformal array validate the proposed design approach. [ABSTRACT FROM AUTHOR]

Microstrip array antennae are the ultimate solution for a variety of system applications, including air traffic control and collision avoidance radar. A microstrip antenna array is used since it is easy to design and fabricate. It has small size, light weight and high gain. Microstrip antenna array design is an important area of research in radar system that can meet the subject requirement. Microstrip antennae are used in a variety of wireless applications, including radars, wireless sensor networks, cellular phones and in medical applications. The paper proposes a design of different microstrip array antennae for weather radar system. Corporate feeding technique is incorporated for the design of an array. The proposed antennae resonate at 5.8 GHz. [ABSTRACT FROM AUTHOR]

Ultra-wideband (UWB) patch antenna for Ku/K band applications is presented. In this paper, a microstrip line feed has been modified to an elliptical gradient structure, and the conventional radiator patch has been developed through the use of the symmetrically circular slots. These modifications have been used to improve the performance of the antenna significantly. Upper and lower frequency ranges achieve UWB antenna performances start from 11.57 GHz to 21.45 GHz. Proposed antenna exhibits good impedance matching, which makes it convenient to work in various applications. Besides that, the reflection coefficient is reduced attained to -31.81 dB over the operating band. The antenna is developed and analyzed using the commercially available software FEKO simulator based on the method of moments (MoM). Other parameters results such as sidelobe level (SLL) and beamwidth (half power - 3 dB) are added and discussed significantly. The proposed design is fabricated and tested experimentally, and the results show that a satisfying agreement with the simulation results. [ABSTRACT FROM AUTHOR]

In this work, the impact of substrate type and design dimensions on bow-tie microstrip antenna performance and bandwidth improvement is presented both numerically and experimentally at 4-8 GHz. The finite integration technique (FIT)-based high-frequency electromagnetic solver, CST Microwave Studio, was used for the simulation analysis. For this purpose, four bow-tie microstrip antennas were designed, fabricated, and measured upon using different materials and substrate thicknesses. Precise results were achieved and the simulated and experimental results showed a good agreement. The performance of each antenna was analyzed and the impact of changing material permittivity, antenna dimensions and substrate thicknesses on antenna performance were investigated and discussed. The measured results indicated that the slot bow-tie antenna, which is one of the novel aspects of this study, is well matched and a 2-GHz bandwidth [5-7 GHz] is obtained, which is about 50% bandwidth in comparison with the wideband applications [4-8 GHz]. The proposed structure is useful in ultra-wideband (UWB) applications. This study provides guidance in selecting material types and thicknesses for microstrip antennas based on desired applications. [ABSTRACT FROM AUTHOR]

In this paper we designed microstrip patch antenna by using metamaterial to improve antenna bandwidth. We inserted Complementary Split Ring Resonator (CSRR) structure between the ground and patch in the substrate. We compared our design with the conventional microstrip patch antenna in point of bandwidth. We obtained bandwidth improvement by 800MHZ. Simulation was obtained by using High Frequency Structure Simulation (HFSS) simulator. [ABSTRACT FROM AUTHOR]

In this paper, a novel design of compact microstrip antenna (MA) using an embedded λ/4 resonator is presented. By utilizing the strong coupling between the λ/4 resonator and the radiation patch of MA, the resonant frequency of MA can be decreased. Besides, the λ/4 resonator is embedded in the patch, which does not enlarge the whole size of MA. Therefore, a compact antenna can be realized. In this paper, after the principle is stated, a sample antenna has been manufactured and measured to prove the predicted characteristics of our proposed antenna. The measurement agrees well with the simulation. Hence, the proposed method in this paper is quite suitable for the design of a compact antenna. [ABSTRACT FROM AUTHOR]

A new single-feed circularly polarized (CP) microstrip antenna with the C-shaped parasitic strip is proposed in this paper. The proposed CP antenna is designed for the transmitting terminal in the Global Navigation Satellite System (GNSS). The square patch is surrounded by a C-shaped parasitic strip. By adjusting the parasitic strip dimension, the antenna CP operation is achieved. The main advantage of this method is that those two resonant modes for achieving the CP operation are independent from each other, which is liable to design and debug the proposed CP microstrip antenna. The designed CP microstrip antenna has the good impedance matching, the good CP radiation pattern, and the stable CP gain across the 3 dB AR (axial ratio) bandwidth. [ABSTRACT FROM AUTHOR]

This paper introduces a Microstrip MIMO antenna with a ladder shape parasitic element that helps to reduce mutual coupling. In this research work a parasitic ladder shape element has been applied in between the antenna elements in which each patch size is (13x17.4) mm2. In order to control the coupling the distance between the elements has been adjusted accordingly. The proposed MIMO antenna operates at 2.28GHz and 2.72GHz resonant frequencies for wireless applications. The purpose of introducing parasitic element is to generate a cancellation field which enhances the isolation developed in proposed MIMO antenna. Above fulfillment is done by using ladder shaped parasitic element of size (43 x 6) mm2 built using FR-4 epoxy with a relative permittivity of 4.4 and with thickness of 1.6mm. The Design was simulated in CST with above mentioned parameters. Proposed MIMO antenna is found to have a low Return Loss i.e. -32dB and -22.25dB respectively at two resonant frequencies. To validate the simulation results, the antenna is experimentally tested in the laboratory. Finally a comparison of the results by changing the ground plane has been presented in the paper. [ABSTRACT FROM AUTHOR]

An efficient approach is presented in this article, to reduce radar cross section (RCS) of a microstrip patch antenna, without affecting other radiation characteristics by the application of a novel hybrid metamaterial (MM) structure. The microstrip antenna is designed to operate at 4.2 GHz. Three different configurations of MM structures (ie, CB_1, CB_2, and hybrid) with splitted square and ring shaped two nonidentical MM cells are designed and critically analyzed in the range of 2‐18 GHz. A hybrid MM configuration is chosen for the design and implementation of low RCS antenna due to its exceptional performance as compared to CB_1 and CB_2. The hybrid MM is organized in chessboard configuration, comprises of splitted square and ring shaped MM unit cell. The results show that proposed antenna gives substantially out of band RCS reduction from 6 to 18 GHz and the proposed antenna has a lower RCS than the reference antenna. Proposed antenna attains wideband bandwidth around 7.4 GHz (ranging 2.0‐4.4 GHz, 7.8‐9.1 GHz, and 14.3‐18 GHz). The maximum reduction of −30.1 dBsm at 16.4 GHz is achieved in the hybrid MM structure impinged microstrip patch antenna. Finally, the fabrication and performance evaluation of MM loaded antenna is carried out. Moreover, measured results of the fabricated samples are closely matched with simulated results, which prove the effectiveness of the adopted approach for practical applications. [ABSTRACT FROM AUTHOR]

In this paper, the main concern is the designing of microstrip structure for Hyperthermia and tissue heating. The purpose of this antenna designing is the capacity of doing an action in 2.24 GHz Frequency and the usage of Silicone tissue in spite of water bolus to decrease the burn percentage on skin to the least degree and solve the problems caused by the water bolus tissue. The function of the antenna by Moment Method and the frequency analysis method is simulated and developed through several stages and biologic tissue which includes three layers (skin, fat, muscle). The improvement in this antenna is the transformation of heating to the upper part of skin and fat layers. The results have been evaluated in four shapes, water bolus, water bolus—silicon, silicon—water bolus, and silicon alone. In first three shapes, the energy is not capable to permeate into the tissue in higher depths; and, it will stay in the fat tissue. Only when silicon has been used, the energy will permeate into the muscular tissue without any damages to the other body tissues. The size of the antenna (0.84 × 45 × 70 mm) and the coaxial 50 Ω has been used for feeding. [ABSTRACT FROM AUTHOR]

This paper presents a printed rectangular slot microstrip antenna array of two elements based on an Electromagnetic Band Gap (EBG) structure. The proposed EBG structure is invented to improve the isolation between the radiating elements for multiple-input multiple-output (MIMO) application. Single and two slotted rectangular microstrip antennas are designed on an FR-4 substrate with a dielectric constant (εr) of 4.3 and loss tangent (tand) of 0.025 with thickness of 1.6 mm. The proposed EBG structure is designed as one planar row of 24 slots. The proposed array performance is tested numerically using Computer Simulation Technology Microwave Studio (CSTMW) of Finite Integration Technique (FIT) formulations. The antenna performance in terms of reflection coefficient (S11), isolation coefficient (S21), radiation patterns, boresight gain and Envelope Correlation Coefficient (ECC) are investigated before and after introducing the EBG structure to identify the significant enhancements. The proposed EBG structure is located between the radiating antenna elements to reduce the mutual coupling of the proposed antenna array. The edge to edge separation distance of the proposed antennas is λ0/16, where the λ0 is the free space wavelength at 2.45 GHz. The simulated results show a significant isolation enhancement from -6 dB to -29 dB at the first resonant frequency 2.45 GHz and from -10 dB to -25 dB at the second resonant frequency 5.8 GHz after introducing the EBG structure to the antenna array. [ABSTRACT FROM AUTHOR]

A microstrip feeding network (MFN) that implements a Dolph–Chebyshev (D-Ch) current distribution is designed to feed a microstrip antenna array (MAA) operating in B2 LTE band. The study consists of three phases. In the first phase, the elements of MAA are directly excited by equi-phase current sources complying with a D-Ch amplitude distribution to ensure a sidelobe level (SLL) of −20 dB. Then, MAA is optimized for maximum forward gain. Finally, the input impedances of the elements of the optimized MAA and the element spacing are recorded. In the second phase, the MFN is considered to terminate at lumped loads with values equal to the input impedances of the respective elements of the optimized MAA and is then optimized to achieve low standing wave ratio, high power efficiency, and output currents equal to those applied in the first phase by the current sources. All optimizations are performed with an improved particle swarm optimization variant in conjunction with CST. In the third phase, the optimized MFN is attached to MAA and is evaluated with CST. The purpose of this study is to show that it is possible to design an MFN that satisfies multiple requirements, without the knowledge of MAA geometry. [ABSTRACT FROM AUTHOR]

A compact tricyclic nested triband microstrip antenna is designed in this paper, which is composed of three metal rectangular rings, an input feed line, and an elliptic-shaped defected ground structure (DGS). To enhance the antenna's radiation performance, a novel artificial magnetic conductor (AMC) reflector characterized with three zero-phases in the reflection coefficient at 2.4, 4.2 and 5.8 GHz is proposed, which mainly consists of complementary split ring resonators (CSRR). The measured S-parameters and radiation patterns agree well with the simulated data. The antenna's three impedance bandwidths span in the ranges of 2.22-2.49, 2.94-4.96, and 5.41-6.62 GHz, respectively, which effectively cover all the 2.4/5.2/5.8-GHz WLAN frequency bands and the 2.5/3.5/5.5-GHz WiMAX bands. Particularly, by adding the designed AMC reflector, the measured antenna gains at the frequency points of 2.4, 2.5, 3.5, 5.5 and 5.8 GHz have been improved with 4.22, 4.42, 1.99, 6.44 and 3.46 dB, respectively. [ABSTRACT FROM AUTHOR]

In order to reduce the time of designing microstrip antenna, this paper proposes a self-renewing fitness estimation of particle swarm optimization algorithm (SFEPSO) to improve the design efficiency. Firstly, a fitness predictive model of the particles is constructed according to the evolution formula of particle swarm optimization (PSO). From the third generation of the algorithm, the fitness of particles is given by the prediction model instead of the full-wave electromagnetic simulation. Aiming to keep the right direction of evolution, the prediction model will be proofed every N generation during the optimization process. If the prediction model accuracy is lower than the threshold, it will be updated and then continue iterating until the particles satisfy the demands. Compared with the traditional optimization method, this method greatly reduces the evaluation time and improves the design efficiency. The method is validated by the optimized design of E-type dual-frequency microstrip antenna and WLAN/WiMAX multiband antenna. The optimized results show that the purpose of rapid optimization can be achieved while ensuring the design accuracy. [ABSTRACT FROM AUTHOR]

Novel and miniaturized hexagonal Microstrip patch antenna design is presented in this paper. Patch is fractured using Sierpinski and Koch structures to make the antenna applicable for multiband applications. Additionally ground is defected to enhance the bandwidth and further size is reduced. Material FR-4 (εr = 4.4)has been chosen to design proposed antenna and substrate thickness as 1.59 mm. Microstrip feed technique is used as it provides better results. Gain obtained in this case is 5.57 dB, 7.49 dB and 4.02 dB with bandwidth as 606.8 MHz, 507 MHz and 2 GHz at 8.3 GHz, 12.6 GHz and 17.6 GHz resonant frequencies. The antenna is better to other designs in terms of parameters like bandwidth, directivity, polarization, gain, return loss and dimension. The antenna provides application for military appliances. A good concord is obtained in Simulated and measured results. [ABSTRACT FROM AUTHOR]

This work proposes the study of patch antennas with fractal slots. Initially, a 2.4 GHz microstrip antenna is designed. Then, the slots in the Koch fractals format are inserted with the iteration 0, 1 and 2. Similarly, it is expected that the antenna can be subjected to various functions in other applications. Simulations using CST STUDIO SUITE Student Edition software are shown, in addition to antenna measurements using the Network Analyzer. [ABSTRACT FROM AUTHOR]

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, a wideband, circularly polarized patch antenna is proposed that leverages the unidirectional resonant modes of a circular patch mounted on top of a grounded dielectric‐ferrite substrate. The proposed antenna is fed via the proximity coupling method and several parasitically coupled patches are placed on a dielectric superstrate to enhance the impedance bandwidth of the antenna. The resonant modes of the structure rotate only in the clockwise or counter clockwise directions. In the frequency range where the effective permeability of the ferrite layer is negative, the resonance frequencies of these modes differ significantly, which produces a large axial ratio (AR) bandwidth. For the proposed antenna, the numerical results show the 10 dB impedance bandwidth to be around 44% and the 3 dB axial ratio bandwidth to be higher than 64%. [ABSTRACT FROM AUTHOR]

Metamaterials (MTMs) have received considerable attention due to their novel electromagnetic properties. Their applications include enhancing gain and bandwidth in microstrip antennas. In this article, a dual band microstrip antenna design based on characteristic mode analysis (CMA) using MTM superstrate is proposed for 5G wireless communication. The CMA is used for the modelling, analysis and optimization of the proposed antenna to examine the underlying modal behaviour of the MTM unit cell and to guide mode excitation. The antenna structure consists of a microstrip feed line connected to a rectangular patch. Then triangular split ring resonator unit cell is inserted on the ground of a traditional patch antenna that resonates at 15 GHz to produce additional resonance at 10 GHz. A planar array of 2 × 3 triangle MTM unit cells is used as superstrate to improve the gain and bandwidth at both resonances simultaneously. The optimal distance between MTM superstrate and the antenna patch is determined using the Fabry-Perot cavity theory to maximize power directivity and efficiency of the proposed antenna. The CST microwave studio software is used to model and optimize the proposed antenna. A prototype of the designed antenna that was fabricated showed good agreement between measurement and simulation results. [ABSTRACT FROM AUTHOR]

A novel, simple, and inexpensive microstrip antenna is designed for vehicle to vehicle communication and specifically for blind spot detection in this work. The proposed antenna is 20.2mm×24.1mm×1.6 mm in size. Since offset feeding technique is used, manufacturing is simple and cheap. ANSYS Electromagnetics Suite 17.2 simulates the antenna. To suppress the losses, Defected Ground Structure is employed. In addition, the Genetic Algorithm is used to optimize the ground plane width to obtain high gain and omnidirectional characteristics. The simulated results conceive that the 'Dedicated Short Range Communication' (DSRC) band is covered by using the antenna. Moreover, the antenna is fabricated, and the measured results are found to be consistent with the simulated ones. [ABSTRACT FROM AUTHOR]

A new technique is presented for designing microstrip patch antennas with very good input impedance matching. The analysis is carried out for 1.78 GHz, 2.42 GHz and 3.46 GHz rectangular patch antennas printed on low-cost fiberglass substrates (FR-4), mounted on a ground plane and fed by a microstrip line. The antenna impedance matching is obtained using a slotted microstrip line feeder. The use of the proposed impedance matching technique showed considerable improvement from the reflection coefficient point of view, with reduction of about 20 dB at the resonant frequency, without modifying the original dimensions of the antenna patch elements or the width of the feeding microstrip line. Numerical characterization is carried out using Ansoft Designer software and iterative method WCIP. Prototypes are fabricated and measured, for validation purpose, showing good agreement when compared to simulated results. [ABSTRACT FROM AUTHOR]

In this paper, the development of two novel circularly polarized microstrip antennas is thoroughly explained. These antennas are fed by coaxial feeding technique. One of the primary objectives of the proposed work is to tune the antennas to work in ISM band. This frequency band refers to the internationally recognized radio frequency bandwidth which is to be used explicitly for Industrial, Scientific, and Medical applications. Therefore, these antennas would be suitable to use in the field of wireless biotelemetry. Two new antenna design techniques have been introduced to produce circular polarization, and details of these schemes are described. The proposed microstrip antennas are designed and simulated on Advanced Design System (ADS) software. The return loss of the proposed crescent-cut antenna is -19.3 dB at the operating frequency. The extended corner antenna has the return loss of -29.3 dB at the tuned frequency. The simulation results are also presented and discussed. [ABSTRACT FROM AUTHOR]

This paper introduces a design of a frequency adjustable dual-band circular patch antenna with a gapring-slot accompanied by a study of a cylindrical TLM method effectiveness and capabilities. The antenna is fabricated on Rogers 4003 substrate and measured results have been used to validate the used approach. Through comparison with corresponding rectangular TLM mesh results, the cylindrical TLM method has been found not only as more efficient requesting much smaller number of cells to be applied but also more capable to accurately describe narrow ring slots and small angular features. The designed antenna resonates at two frequencies, 2.77 GHz and 3.72 GHz, with the possibility of additional frequency tuning. A frequency adjustments study has been carried out and, accordingly, design corrections have been proposed either to independently tune the frequency or to simultaneously adjust both frequencies. [ABSTRACT FROM AUTHOR]

This paper presents a social spider optimization (SSO) design of a small-size microstrip antenna. Two antenna miniaturization techniques, based on the use of a Koch fractal contour and a shorting post (connecting the patch to the ground plane), are combined to enable a major size reduction. The antenna is inset fed by a microstrip line. The developed SSO algorithm is used to find out the best radius and position of the shorting post and the length of the inset feed, to achieve the desired resonant frequency with good impedance matching. Antenna prototypes have been fabricated and measured. The good agreement obtained between numerical simulation and experimental results has validated the design procedure. Compared with a conventional rectangular patch, the antenna resonance frequency is reduced from 2.45 GHz to 730 MHz, which corresponds to a remarkable miniaturization of about 70%. The proposed antenna is suitable for applications in the 700-800 MHz frequency range, such as 4G mobile communication systems. [ABSTRACT FROM AUTHOR]

A compact extended bandwidth UWB microstrip antenna is designed utilizing metamaterial (MTM) doubleside planar periodic structures. The proposed antenna comprises two MTM unit cells made by etching X-shaped slots on the main radiating patch, and four slots at the vertices of a square periodically repeated in two-dimensions on the ground plane. The proposed antenna fabricated on 1.6 mm low-cost FR4 substrate is compact, measuring 27.6 x 32 mm², with relative permittivity of 4.5 and loss tangent of 0.02. It has a broad bandwidth covering 3.2 to 23.9 GHz, with a peak gain of 6.2 dB at 8.7 GHz. The antenna has good radiation characteristics for UWB applications. The measured return loss (S11) of the test antenna fabricated for this study was in good agreement with the simulated results. [ABSTRACT FROM AUTHOR]

With the progress of technologies though the years, the extent of electromagnetic radiations has increased in our environment, so there are increased concerns about health for wireless device users. It has become a necessity to use devices with low Specific Absorption Rate (SAR) to reduce human exposure to the effects of Electromagnetic Fields (EM fields). In this article, the design of a circular microstrip antenna (CMSA) with and without an electromagnetic band gap (EBG) structure is proposed. It is evident from simulated results that CMSA with EBG gives low SAR as compared to CMSA without EBG for the proposed prototype. M-shaped unit cell structure of EBG is designed for 1812 MHz resonance frequency, and a bandwidth of 244 MHz is achieved using CMSA with EBG for LTE Band 3. SAR is reduced by 76.25% when CMSA is used with EBG in comparison to CMSA without EBG. [ABSTRACT FROM AUTHOR]