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This study evaluates the performance of an inset feed-microstrip antenna for various substrate materials (FR4, Rogers 5880, Rogers 6002, Polystyrene, and Ceramic) with different thicknesses (1.6 mm, 3.2 mm, and 4.8 mm) for 5G applications, focusing on key parameters such as return loss, efficiency, directivity, and realized gain. The goal is to determine the optimal substrate material and thickness that offers the best combination of these performance metrics across a frequency range of 3 to 4 GHz. The proposed method uses a new hybrid GA-PSO algorithm with Dynamic Adaptive Mutation and Inertia Control (DAMIC). The study optimized the MSPA design for each material and thickness, followed by detailed simulations using the Advanced System Design (ADS) tool. The approach included parametric analysis and systematic comparisons across the chosen substrate materials, quantifying their performance using specified metrics. Results indicate that Rogers 5880 consistently outperforms other substrates in terms of efficiency, directivity, and gain across all thicknesses. Polystyrene and Rogers 6002 also exhibited commendable performance, especially in the thicker substrates (3.2 mm and 4.8 mm), with Polystyrene achieving the highest directivity at 4.8 mm thickness. Rogers 5880 again led the performance in terms of efficiency, with efficiency values consistently above 70 % across all thicknesses, peaking at 86.38 % at 1.6 mm and 86.39 % at 3.2 mm. Ceramic and FR4 substrates demonstrated relatively lower performance, with Ceramic showing a moderate peak efficiency of 75.98 % at 1.6 mm and 50.79 % at 3.2 mm, while FR4 consistently had the lowest efficiency and directivity values, highlighting its limitations for high-performance antenna applications. Considering the return loss, the Rogers 5880 displayed the most favorable return loss characteristics, maintaining values well below -10 dB across the frequency range, which signifies excellent impedance matching. Rogers 6002 and Polystyrene also showed acceptable return loss characteristics although slightly higher than Rogers 5880, and they remained below 10 dB for most frequencies. Ceramic and FR4 exhibited higher return loss values, suggesting poorer impedance matching and higher signal reflection. In conclusion, The GA-PSO DAMIC optimization technique is a highly effective approach for designing antennas for 5G systems, enabling customized solutions for various substrates. Unlike traditional methods, the GA-PSO DAMIC approach enables precise tuning of key antenna parameters—return loss, gain, directivity, and efficiency—across various substrate configurations and thicknesses. The results demonstrate that the Rogers 5880 substrate, particularly at a thickness of 1.6 mm, consistently offers superior performance metrics, including high efficiency and low return loss, confirming its suitability for 3-4 GHz 5G applications. The results also reveal that Rogers 5880 is the superior substrate for high-frequency applications requiring high efficiency, directivity, and gain, followed by Polystyrene and Rogers 6002, particularly for thick substrates. Ceramic and FR4, although adequate in certain scenarios, are generally less optimal for high-performance requirements because of their lower efficiency and higher return loss. These findings provide critical insights into antenna design and material selection, emphasizing the significance of substrate choice in achieving desired performance metrics in modern RF 5G applications.

ABSTRACT A novel superstrate‐based Vivaldi antenna design characterized by high‐gain and wideband performance is presented. The proposed design configuration features a Vivaldi antenna positioned between high dielectric superstrate (Rogers 6010, εr = 10.2) with copper etched off on both sides and an FR4 substrate that has copper etched on one side only. The introduction of a high permittivity dielectric material above and a reflector below the Vivaldi antenna enables favorable resonance conditions for achieving high‐gain operation. The measured antenna exhibits a peak gain of 17 dBi at 10 GHz, covering an operating frequency range of 6–20 GHz. It also features a narrow half‐power beamwidth and low side lobe level radiation patterns. Unlike existing studies, which rely on metamaterials, electromagnetic bandgap structures, and frequency selective surfaces for gain enhancement, our design employs high‐dielectric constant superstrates. This approach increased the antenna's peak gain by 10 dB. Also, the proposed configuration act as a radome protecting the antenna from Environment. [ABSTRACT FROM AUTHOR]

This study evaluates the performance of an inset feed-microstrip antenna for various substrate materials (FR4, Rogers 5880, Rogers 6002, Polystyrene, and Ceramic) with different thicknesses (1.6 mm, 3.2 mm, and 4.8 mm) for 5G applications, focusing on key parameters such as return loss, efficiency, directivity, and realized gain. The goal is to determine the optimal substrate material and thickness that offers the best combination of these performance metrics across a frequency range of 3 to 4 GHz. The proposed method uses a new hybrid GA-PSO algorithm with Dynamic Adaptive Mutation and Inertia Control (DAMIC). The study optimized the MSPA design for each material and thickness, followed by detailed simulations using the Advanced System Design (ADS) tool. The approach included parametric analysis and systematic comparisons across the chosen substrate materials, quantifying their performance using specified metrics. Results indicate that Rogers 5880 consistently outperforms other substrates in terms of efficiency, directivity, and gain across all thicknesses. Polystyrene and Rogers 6002 also exhibited commendable performance, especially in the thicker substrates (3.2 mm and 4.8 mm), with Polystyrene achieving the highest directivity at 4.8 mm thickness. Rogers 5880 again led the p erformance in terms of efficiency, with efficiency values consistently above 70 % across all thicknesses, peaking at 86.38 % at 1.6 mm and 86.39 % at 3.2 mm. Ceramic and FR4 substrates demonstrated relatively lower performance, with Ceramic showing a moderate peak efficiency of 75.98 % at 1.6 mm and 50.79 % at 3.2 mm, while FR4 consistently had the lowest efficiency and directivity values, highlighting its limitations for high -performance antenna applications. Considering the return loss, the Rogers 5880 di splayed the most favorable return loss characteristics, maintaining values well below -10 dB across the frequency range, which signifies excellent impedance matching. Rogers 6002 and Polystyrene also showed acceptable return loss characteristics although s lightly higher than Rogers 5880, and they remained below 10 dB for most frequencies. Ceramic and FR4 exhibited higher return loss values, suggesting poorer impedance matching and higher signal reflection. In conclusion, The GA-PSO DAMIC optimization technique is a highly effective approach for designing antennas for 5G systems, enabling customized solutions for various substrates. Unlike traditional methods, the GA-PSO DAMIC approach enables precise tuning of key antenna parameters--return loss, gain, directivity, and efficiency-- across various substrate configurations and thicknesses. The results demonstrate that the Rogers 5880 substrate, particularly at a thickness of 1.6 mm, consistently offers superior performance metrics, including high efficiency and low return loss, confirming its suitability for 3-4 GHz 5G applications. The results also reveal that Rogers 5880 is the superior substrate for high-frequency applications requiring high efficiency, directivity, and gain, followed by Polystyrene and Rogers 6002, particularly for thick substrates. Ceramic and FR4, although adequate in certain scenarios, are generally less optimal for high-performance requirements because of their lower efficiency and higher return loss. These findings provide critical insights into antenna design and material selection, emphasizing the significance of substrate choice in achieving desired performance metrics in modern RF 5G applications. [ABSTRACT FROM AUTHOR]

A miniature circularly polarised filtering antenna device is presented here. The device has an impeccably circular radiating patch coupled with pins to stripline circuits with open-loop ring resonators. In the proposed design, the filter's last stage acts as a radiating patch and has a low profile of 0.57λ0 x 0.57λ0 x 0.07λ0 at a centre frequency of 4.26 GHz. The codesigned filtering circuit improves the wide impedance bandwidth and axial ratio of 3 dB bandwidth. The filtenna was designed, fabricated and measured, gaining more than 2.5 dB and S11< -14 dB for an impedance bandwidth of 700 MHz from 4.1 to 4.8 GHz. Impedance bandwidth, which is needed for wireless applications, is 13.33%. The developed circularly polarised codesign filtering antenna was verified using full wave models and testing. The filtering antenna is useful for biomedical applications such as wearable and 5G applications

In the field of electronics, technological advancements bring about alterations in electronic devices. With the fast-paced advancements in the era of communication, the frequency bands are becoming congested. One of the frequencies utilized by Wi-Fi-6, 6 GHz, has garnered its share of attention in these changes. This study proposes the design of a Butterworth Bandpass Filter that can be utilized in the IEEE C Band, employing both lumped elements and microstrip transmission lines. The methodology for determining the length and width of the transmission lines, as well as the considerations taken into account during their modification, is provided. A composite filter comprising of both elements and lines is also presented. The combined filter design is aimed at resolving issues arising from the increasing frequency. During the design process, an 8th-order lowpass filter is generated using the Butterworth normalized table, and a bandpass filter with a 200 MHz bandwidth and a 6 GHz center frequency is obtained through the use of a resonant circuit. The dimensions of the transmission lines are determined using theoretical formulas and verified through Matlab files and the MWO-AWR optimization tool. The voltage gain graphs generated demonstrate that the designs created on an FR4 substrate are suitable for use in the IEEE C Band for Wi-Fi-6. [ABSTRACT FROM AUTHOR]

The study of arbitrary patch antenna design represents a critical endeavor in the advancement of wireless communications technologies. This study delves into the construction of a random patch antenna using 3D electromagnetic software, namely the HFSS simulation program. By altering the antenna's physical structure, particularly its ground plane and patch section, we hope to enhance the antenna's performance. Antenna efficiency as measured by gain, S11 parameter, and bandwidth is compared between two different materials, FR4 and Rogers, with varying relative permittivity. Advancements in communications systems and technologies have been made possible by optimizing efficiency, reducing antenna size, and improving performance through modifications to the patch antenna's material composition and design. [ABSTRACT FROM AUTHOR]

The manuscript represents a metamaterial-inspired superstrate patch antenna with a multiband response. The design consists of three superstrate layers over the patch antennaand SRRloaded over parasitic patches. The performance observation is carried out for 2–10 GHz. The simulation and fabrication are taken into consideration, and comparisonsbetween both of them are included. FR4 is used as a substrate material which helps reduce the structure's cost. The metamaterial approach is incorporated over superstrate regions for the improvement of results. The superstrate approach helps for enhancing the strength and Bandwidth of the design. Impedance response is analyzed for different resonating frequencies to check the metamaterial response. Two types of Parametric Analysis are considered to achieve the targeted goal, like changing feed position and the gap among superstrate layers. The presented work shows eight bands of reflectance response with a minimum value of − 44.83 dB with a Bandwidth of 3.139 GHz, peak directivity of 3.16 dB, a gain of 8.02 dB at 9.04 GHz, maximum E-field distribution of 1.160 × 105 v/m at 6.52 GHz. Presented work compared with other design structures to identify the improvement. Many wireless communication-related applications like military, WiMAX, and Maritime mobile services. [ABSTRACT FROM AUTHOR]

This article proposes an empirical methodology for accurately estimating the relative permittivity ${\varepsilon _r}$εr of FR4 boards, which is essential for designing microstrip antennas at S and C frequency bands. As the relative permittivity of dielectric materials changes with frequency, the proposed method involves selecting a known starting value of ${\varepsilon _r}$εr for an FR4 board and then simulating the reflection coefficient S11 parameters of an antenna design. These simulated parameters are then compared to the measured S11 parameters of a fabricated antenna. A value of ${\varepsilon _r}$εr = 4.55 is accurately determined when the two S11 parameters converge close to the desired design frequency. With the FR4 ${\varepsilon _r}$εr value obtained from this methodology, a slot patch antenna is designed for a frequency of 4 GHz, obtaining a reflection coefficient of |Γ| = 0.035, a bandwidth BW = 117 MHz, and a standing wave ratio (SWR) of 1.0746. The proposed methodology can be used as a tool to estimate the ${\varepsilon _r}$εr of various substrates that are not characterized at high frequencies. [ABSTRACT FROM AUTHOR]

The present study explores the processability and properties of poly(furfuryl alcohol) (PFA)-based composites and draws comparisons with the industry-standard epoxy resin matrices used in printed circuit board applications. A poly(furfuryl alcohol)-based fiberglass prepreg was used to manufacture composite cores laminated with copper foil, which were then integrated in situ into printed circuit board prototypes through industry-typical manufacturing and assembly processes. Both copper cores and printed boards were tested to characterize the electrical properties and overall quality of the prototypes. The fabrication of the copper cores and manufacturing methods of the printed boards are described, alongside the results from the characterization of the cores and the testing of the printed boards. The inherent advantages and disadvantages of the material are highlighted, and areas of improvement for the processability of the material and reliability of the technology are discussed. [ABSTRACT FROM AUTHOR]

This work investigates the influence of Friction Riveting processing conditions on FR4-PCB substrate/AA2024 rivet joints in terms of process temperature evolution, joint formation, and joint physical-chemical and mechanical properties. The joints were manufactured using 4 mm diameter AA-2024-T3 rivets and FR4 laminates of 1.5 mm thickness with single or double copper-clad layers. The evolution of process temperature evolution was recorded on the FR4 substrate surface and correlated with the resulting joint formation. Most joints obtained with double copper clad layers developed process temperatures above 300 °C, whereas joints produced with a single copper clad presented slightly lower temperatures, but still above 250 °C. Rivet anchoring was achieved for both FR4 material combinations in the configuration of a single-base laminate, as well as two and even three overlapped laminates. Thermogravimetric analyses revealed that above 300 °C intensive thermal degradation occurs on FR4 materials (with 30% mass change), followed by decomposition, resulting in non-uniform heat distribution throughout the thickness. The joint ultimate tensile force was higher for double copper-clad layers and the joints achieved within more than one laminate, showing higher anchoring efficiency.

This article presents a compact ultra-wideband (UWB) circular monopole antenna with a frequency-selective surface (FSS) for gain enhancement. The proposed antenna has a circular patch with circular cuts at the edges and is excited by a microstrip feed. The bottom plane is truncated and further modified by two triangular cuts at the sides and one rectangular cut in the middle to improve the radiation characteristics of the UWB antenna. The antenna is designed on an FR-4 substrate with a thickness of 1.6 mm, a relative permittivity of 4.3, and planner dimensions of 30 mm × 30 mm. To improve the proposed antenna’s gain, an FSS is designed that consists of periodic unit cells of metal printed on the upper layer of an FR-4 substrate with dimensions of 0.11λ × 0.11λ at the lowest operating frequency of 3.3 GHz. The FSS shows a very low transmission coefficient and linearly reducing reflection phase with increasing frequency over a frequency range of 3.3–10.8 GHz. The gain of the proposed antenna is increased from 3 dB to 8.1 dB at 9 GHz by placing the antenna on the FSS. Moreover, the prototype of the proposed antenna is fabricated, and the experimental results are measured, which show close agreements with simulated results. The FSS-based antenna has directional radiation patterns, making it a potential candidate for ground-penetrating radar and UWB applications.

Filtering is the process of separating the frequencies we want from a variety of frequencies in various bands, and this type of filtering can be carried out using a tool called a bandpass filter. Wireless transmitters and receivers, military applications (Radar, Electronic Warfare, Identification Friend or Foe (IFF), Submarine Communications, and a variety of other devices use bandpass filters to achieve frequency filtering. The existence of the filter in the most extreme military situations is crucial since these Bandpass filters are utilized for numerous military applications. In this paper, we presented an analysis and simulation of the Hairpin Bandpass filter using HFSS Design Software. The bandpass filter is designed to operate at a frequency of 9GHz. The FR4 substrate with a dielectric constant of 4.4 and 1.6mm thickness was used in this design. The filter that is designed is used in many 5g Applications. [ABSTRACT FROM AUTHOR]

A comparative analysis of a compact planar Square patch Microstrip Multiband antenna on three different substrates is proposed. The proposed design has a C-shaped slot etched on the square radiating part and the antenna is energized using microstrip feed line. RT Duroid (ε r= 2.2), Taconic (ε r= 3.2) and FR4 (ε r= 4.4) substrates are used for simulation analysis. The flow of current is modified by the C-shaped slot making the antenna to resonate at 3/4 and 6 bands for RT Duroid/Taconic and FR4 substrates respectively suitable for 5G sub GHz applications. The antenna has a compact dimension of 32 × 32 × 1.6 mm 3 and exhibits a return loss, S11 of less than -10dB for all the resonating frequencies for all three substrates. The analysis has been done by considering the S11 (Return loss

Design and performance enhancement of an S-shaped antenna with two additional slits and slots is presented. Initially, a parametric study was performed with two commonly used dielectric materials. First, FR4 with ɛr = 4.3 and thickness of 1.55 mm was used, followed by RO4003C with ɛr = 3.55 and thickness of 0.8 mm. Suitable for high frequencies, the RO4003C outperforms the affordable but lossy FR4. Thus, the antenna is fabricated with RO4003C. The simulated and measured results are in good agreement. Since the proposed antenna operates at two resonant frequencies, 10 GHz and 17.65 GHz, it is suitable for both X and Ku bands. The better gain was obtained at 10 GHz, with a measured gain of 6.3 dB. Finally, a comparative table is given, which reveals the superiority of the proposed antenna in terms of gain and compactness over some X-band antennas recently presented. [ABSTRACT FROM AUTHOR]

The paper depicts a microstrip hairpin bandpass filter design, simulation, fabrication and test. The proposed microstrip filter's design is comprised of five hairpin structures separated by a tenth of a mm distance for which various parametric studies have been conducted. The simplicity of design provides inexpensive and undemanding filter. The filter is fabricated with suitable parametric results. The design is based on Chebyshev's values for the prototype, with N (the order of filter) number being equivalent to five. The final fabricated version of the project is based upon FR4 dielectric substrate with the input return loss being below -10 dB and insertion loss above – 2 dB. Approximate values of the input reflection coefficient and insertion loss are -33.34 dB and - 1.72 dB respectively. Furthermore, the frequency range for the proposed geometry is between approximately 2.6 GHz and 3.6 GHz. The proposed filter is fabricated and the results measured in real life are highly correlated to the results simulated in the software. The proposed microstrip hairpin bandpass filter can be utilized in wireless internet access and communication. [ABSTRACT FROM AUTHOR]

This article presents a compact ultra-wideband (UWB) circular monopole antenna with a frequency-selective surface (FSS) for gain enhancement. The proposed antenna has a circular patch with circular cuts at the edges and is excited by a microstrip feed. The bottom plane is truncated and further modified by two triangular cuts at the sides and one rectangular cut in the middle to improve the radiation characteristics of the UWB antenna. The antenna is designed on an FR-4 substrate with a thickness of 1.6 mm, a relative permittivity of 4.3, and planner dimensions of 30 mm × 30 mm. To improve the proposed antenna's gain, an FSS is designed that consists of periodic unit cells of metal printed on the upper layer of an FR-4 substrate with dimensions of 0.11λ × 0.11λ at the lowest operating frequency of 3.3 GHz. The FSS shows a very low transmission coefficient and linearly reducing reflection phase with increasing frequency over a frequency range of 3.3-10.8 GHz. The gain of the proposed antenna is increased from 3 dB to 8.1 dB at 9 GHz by placing the antenna on the FSS. Moreover, the prototype of the proposed antenna is fabricated, and the experimental results are measured, which show close agreements with simulated results. The FSS-based antenna has directional radiation patterns, making it a potential candidate for groundpenetrating radar and UWB applications. [ABSTRACT FROM AUTHOR]

An optimized Koch based fractal patch antenna with twin lower leafs has been designed for appropriate wireless communication applications and capable of exhibiting penta-band behavior. The proposed structure has been created by introducing modified Koch curve on a rhombus shaped fractal patch having compact dimensions of 60 mm×50 mm×1.6 mm with defected ground structure. The reflection coefficient (S11) values of the proposed antenna are -11.97 dB, -20.29 dB, - 25.38 dB, -13.91 dB and -23.48 dB at resonating frequencies of 2.8649 GHz, 6.3514 GHz, 7.1622 GHz, 8.2973 GHz, and 8.9459 GHz, respectively. It has values of VSWR at all resonating frequencies within acceptable range of 1 to 2. The prototype of the proposed structure has been designed on easily available and low cost FR4 epoxy substrate material. The bandwidths of 1.39 GHz, 3.30 GHz, 10.19 GHz, 1.93 GHz and 2.23 GHz has been obtained at all resonating frequencies. The measured results has been analyzed and compared with simulated results and bears a close approximation. The developed prototype can be utilized for applications in S, C, and X frequency band which can further be used for various communication applications like radar, satellite communication and wireless computer networks. [ABSTRACT FROM AUTHOR]

In this study, a compact U-slot patch antenna design based on dielectric measurement approach of Flame Retardant 4 (FR4) material is presented for X band space applications. In accordance with the design method, the measured frequency dependent dielectric constant and tangent loss values of the FR4 material at X-band using the waveguide method is applied to the HFSS design tool to be used in antenna designs. Then, the functional performance of the design method on antennas is verified by comparing the simulation and measurement results of a conventional antenna design in the literature. In the light of the verified results, a new U-slot patch antenna design with lateral side slots for X-band space applications is presented with a feed line by using the proposed design method. The presented compact antenna design provides 1.77 dB gain at the center frequency (9.5 GHz) and the frequency bandwidth from 8.53 GHz to 10.63 GHz. [ABSTRACT FROM AUTHOR]

A comparative analysis of a compact planar Square patch Microstrip Multiband antenna on three different substrates is proposed. The proposed design has a C-shaped slot etched on the square radiating part and the antenna is energized using microstrip feed line. RT Duroid (𝜺r = 2. 2), Taconic (𝜺r = 3. 2) and FR4 (𝜺r = 4. 4) substrates are used for simulation analysis. The flow of current is modified by the C-shaped slot making the antenna to resonate at 3/4 and 6 bands for RT Duroid/Taconic and FR4 substrates respectively suitable for 5G sub GHz applications. The antenna has a compact dimension of 32 × 32 × 1. 6mm3 and exhibits a return loss, S11 of less than -10dB for all the resonating frequencies for all three substrates. The analysis has been done by considering the S11 (Return loss <-10 dB), Directivity, Antenna Gain, VSWR and surface current distribution. Table II provides the comparison of parameters for different substrate material. [ABSTRACT FROM AUTHOR]

In this manuscript, a compact wideband antenna using a partial ground plane has been designed by the hybridization of Minkowski fractal curves on the hexagonal radiating patch. Further, the corners of this partial ground plane have been truncated and the Minkowski curves superimposed on each truncated corner. The L shaped stub has been employed to enhance the performance parameters of the antenna in terms of the number of frequency bands and impedance bandwidth. Different prototypes of an antenna have been compared and found that prototype with L-shaped stub and ground plane with truncated corners using Minkowski curve (proposed prototype) exhibits better antenna performance parameters. The proposed prototype of the antenna reveals the maximum bandwidth of 10.86 GHz (140.10%) with four distinct frequency bands 4.4, 7.1, 10.8, 16.3 GHz. Designed antenna has also been fabricated and tested for authentication of simulated results with measured results and found in reasonable agreement with each other. The proposed antenna uses a low-cost FR4 substrate with a compact size of 24 × 30 × 1.6 mm3. Due to the wider bandwidth, stable radiation pattern, and desired gain at the desired frequency points, the proposed antenna can be used for different wireless applications. [ABSTRACT FROM AUTHOR]

Summary The paper reports an experimental investigation of an 8 × 8 MIMO antenna fabricated on a commercially available FR4 substrate. A fractal printed monopole radiator is introduced as a good prospect for super‐wideband (2.85–20.0 GHz) multiple‐input‐multiple‐output (SWB‐MIMO) configuration. The MIMO antenna is printed on both the planes (Plane A and Plane B) where four antennas are printed on Plane A and remaining on Plane B which are fed asymmetric to achieve wider impedance bandwidth. An inverted‐L type strip is embedded in a rectangular elliptical slotted ground to match the impedance. Also, a circular ring is embedded on both planes with a novel stub connected to each antenna ground providing isolation of more than 30 dB. The diversity performance of the antenna is also investigated with measured envelope correlation coefficient (ECC) < 0.025, directive gain (DG) > 9.995 dB, total active reflection coefficient (TARC) < −40 dB, and channel capacity loss (CCL) < 0.30b/s/Hz in the entire operating band. [ABSTRACT FROM AUTHOR]

A novel double-layer multiband, low-profile frequency selective surface (FSS) for IMT-Advanced (4G) mobile communication system is presented in this article. On aspired to a minimum transmission coefficient of -10 dB for surface materials when the frequency bands targeted for blocking are stopped. For this project, we chose the dielectric substrate FR4 (loss-tangent = 0.02; dielectric constant = 4.54) and a thickness of 1 mm. Dodecagonal rings, upright bars, and square frame make up the FSS unit cell. The desired frequency responses of the FSS were intended to avoid being changed according to the angle of incidence of the electromagnetic waves. The FSS design is proposed as a symmetrical structure to make it polarization-independent and is aimed to stop 800, 900, 1800, 2100, and 2600 MHz frequencies to prevent harmful effects to human health and interference effects at these frequencies. With a cell size of 0.17λ, the planned FSS is quite small and, thus, has a low sensitivity at the angle of the incident wave. In addition, FSS geometry was manufactured by a printed circuit board (PCB) and measured in a non-reflective environment after being studied in Ansys high-frequency structure simulator (HFSS) software. By comparing the analysis and measurement results of the design, the success of the FSS to the frequencies to be stopped has been verified. The effect of each patch on different frequencies has been examined by drawing the surface current density graphs of the design. [ABSTRACT FROM AUTHOR]

The variation geometry of either the patch or substrate or both can help to design the antenna with specific resonant frequency. In this work, a 1X4 array is designed. The novelty of this proposed work is use of thin FR-4substrate of 0.604mm. Four circular metallic patches are placed with 0.62 apart. Also, the metallic patches are considered with small radius of 11.74mm producing wider bandwidth. Sectoral slots are formed in the circular patch for relative gain enhancement and maintaining the resonant frequency. With this novelty, further the defective ground plane is considered for far-field and nearfield effects along with reduction of mutual coupling effect. This satisfies the desired multiband operation along with the gain. The proposed prototype utilized for weather forecasting and broadcasting application that is monitored at the meteorology department. It provides the multiple bands at 7.5GHz, 11.7GHZ &16GHz respectively. Simultaneously, it satisfies the data transmission and reception in the range of 7 to 8 GHz, 11to 12 GHz and 15.5 to 16.5 GHz works for broadcasting. The proposed structure is exhibiting a good amount of bandwidth as well as gain at this application. The gain and bandwidth of this antenna is found excellent that satisfies the simulated result in case of fabricated one. [ABSTRACT FROM AUTHOR]

A Rotman lens antenna array with advantages of self‐packaging, low cost, and broadband is proposed by using substrate integrated suspended line technology at K band. The proposed lens‐fed antenna is designed to be low cost by using only FR4 material on all substrates. Meanwhile, patterned substrate and double metal layers with metalized via hole connecting are utilized to reduce its loss. To evaluate the proposed method, two Rotman lenses with different port numbers are designed, fabricated, and measured. For verification of switch beam property, the quasi‐Yagi antenna array is designed for broadband operation and low profile to integrate with the Rotman lens. The experimental results show that the scanning range is ±24° and ±30° of the two lenses, respectively. [ABSTRACT FROM AUTHOR]

In this paper, a low profile 4 × 4 multiple input and multiple output (MIMO) antenna is proposed and designed for wireless local area network (WLAN) application using a square split-ring resonator. Initially, a single square-patch antenna is designed with square-shaped split-ring slot. Subsequently, the two-element MIMO antenna is designed and it is extended to four-element MIMO antenna. Finally, the defected ground structure (DGS) is implemented in order to enhance antenna performance. The antenna elements are placed opposite to each other. The mutual coupling between the antennas elements is reduced by DGS. The proposed single, two and four-element antennas operate at 5.8 GHz for WLAN. The overall performance is measured in terms of S parameter, radiation pattern, and envelope correlation coefficient. The simulated results are verified through measurements. The simulated and measured results demonstrate that the proposed 4 × 4 MIMO antenna is the most suitable for WLAN applications. [ABSTRACT FROM AUTHOR]

In this paper, a novel integrated microstrip filter technology useful for wideband and narrow band applications is presented. This design integrates both Low Pass Filter (LPF) and High Pass Filter (HPF) design techniques to achieve the desired band pass characteristics. The optimized results achieved for the given structure by proper tuning of the attached stubs. The designed filters are working in the Ultra-Wide Band ranging from 3 GHz to 11 GHz and it is observed that the combinational filter can even work from 2 GHz to 17 GHz. The proposed structure is simulated using MATLAB-Tool Box and the corresponding results are discussed. These filters are more useful for the modern wireless devices for UWB applications. [ABSTRACT FROM AUTHOR]

This work presents a novel method for fast characterization of broadband and continuous dielectric properties of microwave substrates based on an ungrounded coplanar waveguide (UGCPW) structure containing two simple straight lines. The proposed method could, to some extent, alleviate the derivation error due to connector soldering and device fabrication. To verify this point, theoretical analysis and result comparisons are carried out. By considering both the conductor loss and radiation loss, the dielectric loss tangent can be retrieved with a high precision. The deviation of the measured dielectric constant and dielectric loss tangent are found to be within 0.03 (0.68%, 4.37 vs 4.40) and 0.0013 (6.5%, 0.0213 vs 0.02), respectively, in the range from 12 to 20 GHz, which is more accurate than the results reported in the literature, all while the proposed extraction approach is simpler than other methods such as the wave cascading matrix (WCM) algorithm. Due to the UGCPW configuration, this method is suitable for property evaluation of emerging synthesized dielectric materials, as a single round of electroplating process is required for device design, which can eliminate possible consistency error in conductor thickness and roughness caused by multiple electroplating process.

The internal charging effect may lead to electrostatic discharges (ESDs) for Geostationary Earth Orbit (GEO) and Middle Earth Orbit (MEO) satellites. This is due to the high-energy electrons that deposit in the dielectrics of satellites. The properties of the dielectrics such as permittivity and dark conductivity dominate this effect. This may contribute to the ESD risk of long-lifetime satellites if these properties change with the increase of electron dose. Two general materials, Polyimide (PI) and FR4 Epoxy Glass Cloth (FR4), were chosen as samples to study by experiments with different doses. The results show that the permittivity of PI and FR4 decreased as the dose increased while the dark conductivity increased. Numerical simulation evaluates the electron dose and the ESD risk of dielectrics under the electron environment of a specific MEO electron spectrum. The results show that the decrease of permittivity and the increase of dark conductivity will shorten the time constant of internal charging. The quicker build-up of electric field will increase the ESD risk if it exceeds the breakdown threshold. [ABSTRACT FROM AUTHOR]

In this paper, a compact circularly polarized quadrifilar antenna with planar inverted-F antenna (PIFA) elements is presented. The proposed antenna consists of four PIFA elements and a Wilkinson divider-based feed network fabricated on FR-4 substrate (ɛr = 4.4, loss tangent = 0.02, thickness = 1.6 mm). The total size of the antenna is 120 × 120 × 13.2 mm3. Impedance matching with a reflection coefficient <−15 dB and an axial ratio (AR) <3 dB are achieved over the global ultra-high frequency (UHF) radio frequency identification (RFID) frequency band and beyond. The realized gain ranges from 2.25 to 3.75 dBic within the frequency band of interest from 860 to 960 MHz with a directional radiation pattern. The proposed antenna is compact, low-cost and extremely wideband in terms of matching and AR compared to state-of-the-art UHF RFID reader antennas. [ABSTRACT FROM AUTHOR]

In the paper, the model of micron-level crosstalk interconnections was constructed based on FR4 substrate. By changing the input variables of the length and the spacing, this prediction model could provide useful information for Crosstalk intensity. With the increase of the length of the interconnect, the crosstalk intensity of the proximal end and the distal end increased. When the interconnect spacing increased, the trend of crosstalk was not changed, but the intensity decreased gradually. Which provided an experimental reference for future methods of reducing crosstalk from the perspective of physical structure. [ABSTRACT FROM AUTHOR]

In this article, a new approach is proposed for the measurement of the uniaxial anisotropic dielectric constant of different planar samples by means of a single sensor. The sensor is based on a couple of straight-line coupled resonators in microstrip technology that can be excited in odd and even propagation modes. This sensor is designed on an isotropic substrate at the design frequency. Due to the electric field configuration specific for each mode, it is possible to relate these modes to the dielectric constant in two different directions (parallel and perpendicular) of a dielectric material placed on top of the sensor. This technique is used for the successful characterization of the dielectric constant anisotropic of anisotropic dielectrics (FR4, Rogers 4350B, and Arlon Diclad 880), and the isotropic material PTFE. [ABSTRACT FROM AUTHOR]

A new technique for designing compact, notched filter is presented in this paper. The proposed approach is based on the design and optimization of micro strip patch band stop filter, which acts as the unit cell of a higher order filter. This unit cell is composed of half wavelength transmission line method. The proposed filter is designed for military band applications (4–8 GHz) by using low cost substrate material FR4. The proposed filter is designed and simulated through the HFSS software. The filter is fabricated and tested. Finally the measured result is compared with the simulation result. [ABSTRACT FROM AUTHOR]