FR4 Substrate Material Research Articles

A compact diplexer using meander-line resonators and a new coupled junction for 5G and WiMAX application

In this paper, a miniaturized microstrip diplexer designed on an FR4 substrate material is presented. The diplexer operates at 2.4 and 3.5 GHz, responding to the demands of 5G and WiMAX applications, respectively. It consists of two distinct bandpass filters (BPFs) formed using the meandrous line, which are combined using a coupled-junction. An electromagnetic (EM) simulator was used to characterize the frequency responses of the designed diplexer. The results show that the proposed diplexer exhibits excellent isolation, exceeding 28.5 dB throughout the operating frequency range. Additionally, the passband insertion losses are approximately 1 dB, while the return losses measure around 39 and 57 dB for the both channels, respectively. Furthermore, the manufactured diplexer is compact with final dimensions of 28.5 × 20 mm2. These results confirm the suitability of the proposed diplexer for the intended applications.

Dielectric resonator antenna with square slot dgs and amc support for gain enhancement

A miniatured Dielectric Resonator Antenna (DRA) designed on Defected ground structure (DGS) with backing of Artificial Magnetic Conductor (AMC) is presented in this work. The designed antenna showing wide bandwidth to cover WLAN, Wi-Fi and 5G communication applications under sub 6 GHz range and X-band for satellite communication device applications. Antenna occupying the dimension of 35 × 30 × 1.6 mm on Rogers RT-duroid 5880 substrate material, DRA on alumina material of permittivity 9.8 with dimension of 25 × 20 × 10 mm and the AMC surface of dimension 60 × 58 × 1.6 mm on FR4 substrate material. The constructed antenna resonating in the wide band from 3.4–11.5 GHz by holding overall bandwidth of 8.11GHz and an impedance bandwidth of 139%. The DRA placed over the antenna providing the axial ratio at two bands of 4.2–6 GHz and 9.2 to 11.4 GHz with axial bandwidth of 36% and 28% respectively. The placement of AMC structure beneath the antenna exhibiting an improvement in gain of 9% and an average gain attained in the operating band is around 7.2 dBi. The unique combination of monopole antenna with DRA and AMC providing excellent bandwidth, axial ratio and gain.

Dual-band dual-truncated R-slot loaded monopole patch antenna using a single-layer bandstop FSS reflector for gain enhancement

New reflector structure (RS) based on ultra-wide stopband single-layer frequency selective structure (FSS) for mid-band sub-6 GHz 5G applications is designed. The proposed RS is arranged into array of 7 × 7-unit cell of FSS elements for antenna gain and front-to-back ratio enhancement. The single antenna element of volume 30 × 20 × 1.6 (in mm3) consists of a dual-quarter-circular truncated edge-fed rectangular slot (R-slot) loaded rectangular patch (R-patch) antenna with degraded ground structure (DGS) to operate at 3.6 GHz mid-band sub-6 GHz 5G and 5.8 GHz WBAN band. The proposed unit cell FSS element, the RS of volume 55.5 × 55.5 × 13.2 (in mm3) and the associated antenna are designed on lossy thin FR-4 substrate material and investigated numerically using commercial computer simulation technology microwave studio (CST-MS) software. The studied dual-structure based RS made with array of single-layer FSS and monopole R-patch antenna is fabricated and measured. The measured impedance bandwidth (IBW) of 48.28% (3.06–4.85 GHz) and 86.20% (5–10 GHz), peak gain of 5.36 and 7.45 dBi, radiation efficiency of 67.11% and 80.16%, and front-to-back ratio of 12.23 dB and 22.84 dB are achieved at the resonant frequencies 3.5 and 5.8 GHz respectively. The FSS reflector associated with the dual-band monopole R-patch antenna performances are in good agreement with the portable wireless applications requirements.

A Split Square-shaped Metamaterial Loaded Microstrip Patch Antenna for 5G Communication

This paper describes a split square-shaped metamaterial (MTM) design which was applied for the performance enhancement of a rectangular-shaped microstrip patch antenna (MPA). A proposed split square-shaped MTM-based microstrip patch antenna resonates at two frequencies, 18.57 GHz and 25.24 GHz. In both cases, the bandwidths were obtained at 2 GHz and 6.72 GHz respectively. The proposed antenna was designed on FR-4 substrate material, with the dimensions of 20×20 mm2. For the performance investigation, the MTM was placed first at the front side of the antenna and subsequently placed at the back side of the antenna. It was found that the antenna showed better performance when the MTM was placed at the back side of the antenna instead of the front side. The wide bandwidth, high directivity and enhanced gain have made the antenna a potential one for the 5G communication.

Left-handed metamaterial based on circular split ring (CSRR) resonator for microwave sensing Application

This paper presents a new metamaterial structure specifically designed to operate in the L, S, and C frequency bands. It is characterized by a small unit cell size of 15mm × 15 mm. The metamaterial's electromagnetic properties are thoroughly examined, utilizing FR-4 substrate material and copper circular split ring resonators (CSRRs). The Computer Simulation Technology (CST) software uses the finite integration technique (FIT) to precisely model the effective parameters over a frequency range of 0–6 GHz. In simulations and experiments, the structure demonstrates negative refractive index, effective permittivity, and effective permeability. The electric and magnetic field distributions within the unit cell are accurately characterized using vector fields. In addition, the equivalent circuit is simulated and depicted using ADS software, with comparisons drawn between the measured data and the simulated data. The experimental validation, conducted using six varying thicknesses of FR4 materials, verifies the resemblance between the simulated and the measured transmission coefficients. Moreover, the effective medium ratio (EMR) of the metamaterial is calculated to be 12.74, indicating its promising capabilities for microwave sensing applications. The examination of the sensor model uncovers such metrics as quality factors, frequency detection resolution (FDR) values, and sensitivities, all of which enhance our comprehension of the material's performance. This discovery has the potential to advance the development of sensing metamaterials, which could significantly impact various applications and enhance research in the field.

Modelling of Whispering Gallery Mode Resonators for Dielectric Measurement Applications

This study presents a method for measuring the permittivity of dielectric materials using a whispering gallery mode ring resonator. By detecting changes in coupling resulting from variations in resonant frequency caused by alterations in dielectric constant, the method offers a reliable means of characterizing dielectric properties. Operating within the 5-6 GHz frequency range, the presented resonator design leverages printed circuit board (PCB) technology and FR4 substrate material for cost-effective fabrication and flexibility in design. Through comprehensive electromagnetic simulations using ANSYS HFSS software, the study optimizes resonator parameters to enhance sensitivity and effectiveness for various applications. Experimental validation demonstrates exceptional coupling efficiency and sensitivity, underscoring the potential of whispering gallery mode resonators for environmental monitoring, chemical sensing, telecommunications, and biomedical diagnostics. This research contributes to advancing sensing technology, offering valuable insights into the design and optimization of whispering gallery mode resonators for practical use. Further exploration is warranted to fully realize their potential across diverse applications and operating conditions.

A compact dual-band frequency reconfigurable antenna with pin diode integration for smartwatch application

ABSTRACT In this article, a novel frequency reconfigurable antenna for Wi-Fi and WiMAX applications is proposed. The antenna uses PIN diodes for frequency reconfigurability, allowing it to seamlessly switch between two distinct frequency bands centred around the resonant frequencies of 4.1 GHz in the ON state and 5.2 GHz in the OFF state. The input reflection coefficient obtained from the designed antenna is below −10 dB. The measured and simulated gain of the antenna is 4 dBi and 2.65 dBi at resonating frequencies 4.1 GHz and 5.2 GHz the measured and simulated gain is 3.2 dBi and 2.93 dBi, respectively. The radiation pattern exhibits the same for both states. Optimization of the antenna’s dimensional parameters is done with the help of CST simulation software and the electrical parameter such as input reflection coefficient is measured using a Vector Network Analyzer to validate the prototype. The proposed antenna is fabricated on FR-4 substrate material with a thickness of 1.6 mm and a relative permittivity of 4.4. The proposed antenna’s size is 30 × 30 × 1.6 mm3 which is compact and suitable for smartwatch applications. The proposed antenna is compact and remains a good candidate for integration with the smartwatch.

Design of a Dual-Band Printed Antenna for Modern Wireless Communications and Internet of Things Applications

Wireless technology is increasingly influenced by the advanced technological development of antennas. With the rapid expansion of Internet of Things ( IoT) application in the contemporary communication networks, the demand for small printed antennas is increasing, due to their small size and ease of design and manufacture to suit their various application. In this paper, the antenna is designed which is operating at two different frequency bands 2.40GHz and 5.78GHz. The design parameters of the antenna have been calculated using the transmission line model, and an antenna design program has been used for the simulation process is HFSS ( High frequency simulator structure ) tool, which is based on Finite Element Method (FEM). In this work, the proposed slot dual band patch antenna is implemented using FR4 substrate material with a thickness 1.6mm and relative permittivity 4.4. The size of the proposed antenna is just (28 × 27.7mm). The proposed antenna has Omni-directional radiation patterns on most of the operating band. The dual band antenna is designed by adding a slot to the top of the radiated patch. Therefore, the proposed dual- band antenna shows good performance, which is suitable for modern wireless communications and Internet of Things (IoT) applications. The measurements are found to be in good accordance with the simulated results.

A COMPACT HONEYCOMB-STRUCTURED RECONFIGURABLE ANTENNA WITH COPLANAR WAVEGUIDE FEED FOR MULTIBAND WIRELESS APPLICATIONS

The design and implementation of reconfigurable antennas in wireless applications play a tremendous role in minimizing the hardware size of wireless devices. An antenna with the potential to vary its frequency of operation, radiation pattern, and polarization according to the requirement is known as a reconfigurable antenna. Here a novel honeycomb-structured frequency and pattern-reconfigurable monopole antenna has been designed. A honeycomb structure provides better bandwidth as it has multiple edges; angles of the hexagon allow for more efficient radiation and reception of electromagnetic waves and it offers a symmetric radiation pattern. It is compact, with higher packing density. A lowcost FR-4 substrate with a thickness of 1.5 mm and a compact size of 25 mm × 42 mm is used in the design. The antenna can be operated in four modes using two PIN diodes. In mode 0 it can resonate at 2.4 GHz, which is commonly used for Wi-Fi and Bluetooth communication, while in mode 1 it operates at 2.8 GHz and 1.8 GHz for mobile communication. In mode 2 it operates at 2.7 GHz as well as 1.8 GHz, and in mode 3, it works at 1.8 GHz and 3.6 GHz for WiMAX communication. This antenna has a peak gain value of 3.99 dBi. Thus, by changing the geometry/structure, antenna performance can be improved. The proposed design is fabricated on FR-4 substrate material, and the parameters such as return loss (S<sub>11</sub>) and bandwidth are validated. The simulated results and the measured results match well.

Design and Simulation of Elliptical Shaped Microstrip Patch Antenna Using HFSS

Abstract: The elliptical patch antenna presents a comprehensive study on the design, fabrication, and performance analysis of an operating at 2.4 GHz, employing FR4 substrate material. The elliptical shape is chosen for its unique radiation characteristics and compact form factor, making it suitable for integration into modern wireless communication systems. The design process involves careful consideration of key parameters, including patch dimensions, feedline structure, and ground plane geometry. Advanced simulation tools, such as electromagnetic simulators, are employed to optimize the antenna's performance, achieving desirable characteristics such as low return loss and enhanced bandwidth. Utilizing FR4 as the substrate material offers several advantages, including costeffectiveness, ease of procurement, and compatibility with standard PCB manufacturing processes. The dielectric properties of FR4 are thoroughly analyzed and incorporated into the antenna design process to ensure accurate simulation results. The proposed elliptical patch antenna has promising applications in various wireless communication systems, including Wi-Fi, Bluetooth, and IoT devices, operating in the 2.4 GHz frequency band. Its compact size and robust performance make it a compelling choice for space-constrained and high-performance wireless communication applications. This contributes valuable insights into the design and optimization of patch antennas, particularly those using FR4 substrates, and serves as a foundation for the development of efficient and cost-effective wireless communication solutions in the 2.4 GHz spectrum.

Radio Mobile Communications Systems Antenna’ Analysis and Design

In this paper, a 4G and 5G microstrip patch antenna (MSPA) design and performance analysis for fifth-generation communication systems is presented. The antenna is designed using FR-4 substrate material with thickness of 1.1 mm, and dielectric constant (εr) of 4.3.This antenna is previewed to operate at 4.2 GHz for 4G and this will also be used with 28 GHz for 5G. Analysis was conducted using CST (Computer Simulation Technology) simulator. The simulation results are shown for these frequencies. This is explained including their respective bandwidths, HPBWs and gains. Tested antenna shows a good gain of 4.38dBi at 4G frequency of 5GHz and an excellent gain of 7.85dBi for 5G frequency at 27GHz. Results are enabling this antenna for 4G and 5G network mobile application.

Single iterated fractal inspired UWB antenna with reconfigurable notch bands for compact electronics

A simple, compact, and low-profile antenna operating over ultrawideband with high gain is presented in this manuscript. The antenna has dimensions of W × L = 19 mm × 21 mm and is placed on the rear side of the FR-4 substrate material. The antenna contains simple geometry, inspired from a circular fractals, which consists of a circular patch with a CPW feedline. The circular patch is loaded with two fractals patches at both top end of the substrate and the rectangular stub is loaded at the lower side, to improve the antenna's bandwidth. The constructed antenna offers a wide band of 3–13.5 GHz. The antenna geometry also contains three semicircular slots, which are etched to generate the notch bands. Each slot is etched step by step, giving notch bands at 3.9 GHz, 5.2 GHz, and 8.1 GHz. In the final stage, two diodes are added to attain reconfiguration. The antenna offers moderate gain and high radiation efficiency. The hardware model of antenna is engineered to verify the simulated results. Moreover, the antenna is compared with other works in literature. The outcomes of the proposed antenna and comparison with the literature work make the suggested work the best candidate for future UWB portable devices.

Compact SCSRR‐based quad‐band antenna for Bluetooth, WiMAX, WLAN, and fixed‐satellite services

SummaryThis research describes the detailed analysis and design of the compact complex‐free structural metamaterial quad band radiating element applicable for Bluetooth, WiMAX, WLAN, and fixed‐satellite service. The radiating element designed is composed of an inner angle‐rotated circular Split Ring Resonator (SRR) placed within the outer square‐shaped SRR interlinked by a strip to design the multiband operational characteristics and is fed by a coplanar waveguide. Suggested radiating element is imprinted over the FR4 substrate material with the electrical dimension of 28 × 31.26 × 0.8 mm3. The initial outer‐closed square ring offers dual‐band operation by resonating at 2.8 and 8.5 GHz frequencies, and the incorporation of a circular SRR offers quad‐band operation. The unique negative permeability feature of the proposed Square and Circular Split Ring Resonator (SCSRR) structure is extracted, and its band characteristics are analyzed. Results obtained from the simulated radiating element are validated with the fabricated antenna. The measured E plane pattern resembles a numeric eight shape, and the H plane pattern is omnidirectional. Suggested SCSRR antenna offers a gain of above 3.2 dBi in all the operating bands.

Dual Band F-Antenna for Europe and North America

A single antenna for multiple bands are always beneficial from the design point of view. Here a single antenna which is fundamentally inverted F antenna is used, the uniqueness of the design is that , it uses trap technique to produce dual resonance from a single inverted F antenna . The trap used to block the current due to some frequencies and passes the current contributed by other frequencies. So in short , this trap is like a RF filter which has some passband as well as stop band. This trap approach uses a LC network to achieve this design goal .The two bands of interest are 865-870 MHz and 902-928 MHz .. The challenge of this design is that the frequency separation of the two bands is very small. In this case, and also the extra section for low frequency band is too small. Then, the influence of trap LC component variation due to tolerance to the two resonant frequencies is big, and so it is difficult to achieve good in band return loss within the LC tolerance. This is the main difficulty of this design. This issue is resolved by placing the low band section away from the end of the antenna. The antenna is designed on FR4 substrate material having thickness of 1.6 mm and hence it is a low cost solution which could use in various commercial applications which follows these bands.

A sub 1 GHz ultra miniaturized folded dipole patch antenna for biomedical applications

A miniaturized folded dipole patch antenna (FDPA) design for biomedical applications operating at sub 1 GHz (434 MHz) band is presented. Antenna is fabricated on FR-4 substrate material having dimensions of 16.40 mm times 8.60 mm times 1.52 mm (0.023lambdatimes 0.012lambdatimes 0.002lambda). Indirect feed coupling is applied through two parallel strips at bottom layer of the substrate. The antenna size is reduced by 83% through lumped inductor placed at the center path of the radiating FDPA, suitable for biomedical (implantable) applications and hyperthermia. Moreover, Impedance matching is achieved without using any Balun transformer or any other complex matching network. The proposed antenna provides an impedance bandwidth of 6 MHz (431–437 MHz) below − 10 dB and a gain of − 31 dB at 434 MHz. The designed antenna is also placed on a human body model to evaluate its performance for hyperthermia through Specific Absorption Rate (SAR), Effective Field Size (EFS), and penetration depth (PD).

A Compact MIMO Multiband Antenna for 5G/WLAN/WIFI-6 Devices.

This research work presents a compact design of a Multiple-Input Multiple-Output (MIMO) multiband antenna along with high-isolation characteristics. The presented antenna was designed for 3.50 GHz, 5.50 GHz, and 6.50 GHz frequencies for 5G cellular, 5G WiFi, and WiFi-6, respectively. The fabrication of the aforementioned design was undertaken using FR-4 (1.6 mm thickness) substrate material with a loss tangent and relative permittivity of about 0.025 and 4.30, respectively. The two-element MIMO multiband antenna was miniaturized to 16 × 28 × 1.6 mm3, making it desirable for devices operating in 5G bands. High isolation (>15 dB) was attained with thorough testing without employing a decoupling scheme in the design. Laboratory measurements resulted in a peak gain of 3.49 dBi and an efficiency of around 80% in the entire operating band. The evaluation of the presented MIMO multiband antenna was carried out in terms of the envelope correlation coefficient (ECC), diversity gain (DG), total active reflection coefficient (TARC), and Channel Capacity Loss (CCL). The measured ECC was less than 0.04, and the DG was well above 9.50. The observed TARC was also lower than -10 dB, and the CCL was below 0.4 bits/s/Hz in the entire operating band. The presented MIMO multiband antenna was analyzed and simulated using CST Studio Suite 2020.

Triple-Band Notched Ultra-Wideband Microstrip MIMO Antenna with Bluetooth Band.

In this paper, a novel ultra-wideband UWB antenna element with triple-band notches is proposed. The proposed UWB radiator element operates from 2.03 GHz up to 15.04 GHz with triple rejected bands at the WiMAX band (3.28-3.8 GHz), WLAN band (5.05-5.9 GHz), and X-band (7.78-8.51 GHz). In addition, the radiator supports the Bluetooth band (2.4-2.483 GHz). Three different techniques were utilized to obtain the triple-band notches. An alpha-shaped coupled line with a stub-loaded resonator (SLR) band stop filter was inserted along the main feeding line before the radiator to obtain a WiMAX band notch characteristic. Two identical U-shaped slots were etched on the proposed UWB radiator to achieve WLAN band notch characteristics with a very high degree of selectivity. Two identical metallic frames of an octagon-shaped electromagnetic band gap structure (EBG) were placed along the main feeding line to achieve the notch characteristic with X-band satellite communication with high sharpness edges. A novel UWB multiple-input multiple-output (MIMO) radiator is proposed. The proposed UWB-MIMO radiator was fabricated on FR-4 substrate material and measured. The isolation between every two adjacent ports was below -20 dB over the FCC-UWB spectrum and the Bluetooth band for the four MIMO antennas. The envelope correlation coefficient (ECC) between the proposed antennas in MIMO does not exceed 0.05. The diversity gains (DG) for all the radiators are greater than 9.98 dB.

2X2 MICROSTRIP PATCH ARRAY BEAM STEERING ANTENNA WITH PIN DIODES

This paper introduces a novel design of a 2x2 microstrip patch array beam steering antenna integrated with pin diodes. The antenna system enables dynamic control over the beam direction, allowing for efficient wireless communication in various applications. By incorporating pin diodes, the electrical length of the patch elements can be modified, resulting in beam steering capabilities. The antenna operates in the 1.8 – 3 GHz band frequency range, utilizing cost-effective FR4 substrate material. Simulation and experimental evaluations demonstrate the antenna's performance, including return loss, radiation pattern, and beam steering range. This research contributes to the advancement of beam steering antenna technology, providing a practical and affordable solution for enhancing wireless communication systems.

Performance analysis of rectangular microstrip patch antenna with partial ground plane

This paper addresses the design of a rectangular microstrip patch antenna for wireless communication applications at 3.5 GHz resonant frequency. HFSS V13 software was utilized to develop and simulate the antenna. The FR-4 (flame retardant) substrate material, which has a dielectric constant of 4.4 and a thickness of 1.6 mm, was used to design the antenna. The microstrip antenna has a ground dimension of 53.4182mm*34.822mm and a 50Ω impedance. The drawbacks with this microstrip antenna are high VSWR (voltage standing wave ratio) and the return loss is greater than -10db.There are many ways to get over these drawbacks, but one of them is to alter the size of the antenna—specifically, to change the ground plane's size by 37mm*34. 822mm.This paper compares various antenna parameters, including return loss, VSWR, gain, and directivity by switching the ground plane to partial ground plane.

Metamaterial and SIW inspired isolating fences for lateral de-coupling in MIMO antenna

This paper proposes seven isolating fences (IF) for MIMO using novel rotated complementary split ring resonators (RCSRR) and half-mode substrate integrated waveguides (HMSIW) for decoupling. The removing mutual coupling, especially in the lateral direction that is mainly due to surface and space waves is challenging in MIMO. The proposed method involves the RCSRR, HMSIW, and defected ground structure (DGS) to reduce the lateral mutual coupling. In terms of S parameters, radiation pattern, envelope correlation coefficient (ECC), diversity gain (DG), channel capacity, mean effective gain (MEG), and efficiency the performance of the MIMO antenna is examined. The proposed MIMO has the size of 35 × 48 × 1.6 mm3 is made of FR4 substrate material with a centre frequency of 10 GHz, a bandwidth (BW) of 12 GHz, and a gain in the range of 3.7–4.3 dBi.