Meander Line Research Articles

Attenuation of an ultrashort pulse in a folded meander microstrip line with two passive conductors

SummaryIn this article, we investigated a new structure of a protective meander line (ML): a meander microstrip line (MSL) with two passive conductors. The existing theory of ultra‐short pulse (USP) attenuation in MLs is presented for the first time. Based on this theory, we determined the number of decomposed pulses at the output of the MSL line with two passive conductors, and, for the first time, formulated the conditions for pulse decomposition in the line. The folding of the MSL line into non‐core turns was studied in detail. As a result of this article, we proposed a new theory that involves the utilization of additional groups of decomposed pulses for enhanced USP attenuation. These additional groups were thoroughly examined, and the delays of pulses from these groups were defined. This analysis allowed identifying the reason for their appearance. It was revealed that folding the ML into non‐core turns allows further attenuation of the USP amplitude, which increases with the increase of the number of non‐core turns. To validate the obtained simulation results, we performed experimental measurements and obtained good consistency of the results. The N‐norms analysis demonstrated that the combined use of such folding and passive conductors reduces the probability of electrical breakdown, arc discharge, and dielectric breakdown. The maximum USP attenuation at the output was 24.9 dB. As a result of useful signal integrity analysis, it is proposed to use a folded MSL together with a USB 2.0 “Full‐speed” interface with a data transfer rate of 12 Mbit/s. In addition, it is proposed to use such MSLs in DC power circuits.

Ultra-compact and efficient photonic waveguide bends with different configurations designed by topology optimization

Transporting light signals over the corners and sharp bends imposes high optical loss and distortion on the mode profiles. Usually, bends with larger radii are used in circuits to minimize the loss over transmission, resulting in a severe limitation in integration density. In this paper, we propose novel topology-optimized optimized L-bend and U-bend structures designed for a 220 nm silicon-on-insulator (SOI) platform. Optimized L-bends with footprints of 2.5 µm × 2.5 µm, 1.5 µm × 1.5 µm, and 1 µm × 1 µm show maximum insertion losses of only 0.07 dB, 0.26 dB, and 0.78 dB, respectively. For optimized U-bends with footprints of 3 µm × 3.6 µm, 2.5 µm × 2.5 µm, and 1.5 µm × 1.5 µm, the maximum insertion losses are 0.07 dB, 0.21 dB, and 3.16 dB. These optimized bends reduce the maximum insertion loss by over 50% compared to un-optimized arc-type bends across a broad wavelength range of 1450–1650 nm. Experimental verification of a meander line with 16 optimized U-bends (3 µm × 3.6 µm) demonstrates an averaged insertion loss of 1.23 dB in the wavelength range of 1520–1580 nm, agreeing with simulated results and indicating a high potential of loss reduction with optimized bends.

Novel Polyimide-Based Conformal Bandpass FSS for X-band RADAR Communications

A linearly polarized wide bandpass frequency selective surface (FSS) for RADAR communication application has been presented. The proposed FSS is constructed in a single layer with a size of 0.25 λ0. This FSS utilizes a rhombus slot comprised of a head slot and a meander line to provide a single-wideband resonance. The proposed FSS operates in the X-band communication frequency range from 7.98 to 12.1 GHz (4.12 GHz) and achieves a minimum insertion loss of 0.1 dB, respectively. The designed FSS is developed on a flexible substrate with a low profile of 0.05 mm. The FSS exhibits stable angular performance in the scope of incidence angle of 60º for both TE and TM modes. An equivalent circuit model is designed to depict the desired frequency response. Furthermore, a bending analysis has been carried out to verify the conformal nature of the proposed unit cell. The prototype is fabricated and the performances are validated with experimental results.

High gain antipodal meander line antenna for point-to-point WLAN/WiMAX applications

This paper introduces a planar antipodal meander line antenna fabricated using RO3003 substrate. The proposed antenna is designed to radiate in the end-fire direction, achieving a maximum measured gain of 10.43 dBi within its working bandwidth, which ranges from 2.24 GHz to 2.7 GHz, covering long-range WLAN/WiMAX applications. A systematic procedure is adopted in the design process to prove its tunability to cover other application requirements in terms of gain and bandwidth. The proposed design steps show that the bandwidth and the gain can independently be controlled by adjusting specific design parameters such as the number of radiators and the scaling factor. The antenna is fine-tuned using sensitivity analysis and parametric study to guarantee optimum operation at the desired bandwidth. Experimental measurements of the fabricated design demonstrate a high degree of correlation with simulations conducted using CST and HFSS. In comparison to other end-fire antennas presented in the literature, the proposed design manifests its capability to provide high gain for WLAN/WiMAX nodes connectivity. The measurements show that the proposed traveling wave antenna exhibits a high radiation efficiency with maximum value of 99.8% at 2.35 GHz. The measured side lobe level is found to be below -18\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$-18$$\\end{document} dB and -20\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$-20$$\\end{document} dB at 2.45 GHz along the E\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$E$$\\end{document}- and H\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$H$$\\end{document}-planes, respectively. Apart from its excellent radiation performance, the antenna is characterized by its low profile and fabrication simplicity.

Absorption-transmission-diffusion-type radar cross section reduction metasurfaces based on frequency selective absorber and polarization conversion chessboard structure

Absorption-transmission-diffusion-type radar cross section (RCS) reduction metasurfaces based on the frequency selective absorber and the polarization conversion chessboard structure are proposed in this paper. The RCS reduction metasurfaces consist of three parts, i.e. the top layer realized by a cross-shaped meander line loaded with lumped resistors for low-frequency absorption and high-frequency transmission, the mid-layer constructed by angular ring vias frequency selective surface (FSS) sandwiched with two square patches FSS for broadband transmission in mid-frequency zone, and the bottom layer employed chessboard metasurfaces composed of dual-arrow type polarization conversion units for scattering cancellation in high frequency zone. The physical mechanisms of the RCS reduction metasurfaces with multifunctional electromagnetic controlling including wave absorption, bandpass transmission, polarization reversal, and phase cancellation are also discussed and analyzed. Simulation and experimental results demonstrate a reflection of lower than −10 dB for normal incident linearly polarized waves over a frequency range of 2.5 GHz–18 GHz, with a relative bandwidth of 151.22%; transmission passband properties with insertion loss better to −3 dB in the frequency range of 5.62 GHz–11.0 GHz, with a relative bandwidth of 64.74%. Due to the resonance-coupling-resonance principle, the broadband transmission with low insertion loss was obtained. The RCS properties of the proposed multi-functional metasurfaces were further analyzed by numerical simulation and experimental measurement, and the results showed that RCS reduction of over 10 dB was achieved for normal incident different polarized waves at the frequency range of 2.5 GHz to 17 GHz. Even in the case of normal incidence, there was a deviation between the reflection characteristics and RCS reduction. The RCS reduction metasurfaces are expected to be employed in applications where multi mechanism collaborative control of electromagnetic waves is of extreme importance.

Novel printed passive ultra high frequency radio frequency identification antenna using meander technique

<p>In this paper, a novel radio frequency identification (RFID) antenna using a meander technique associated with a slotted patch is studied for RFID applications in the ultra high frequency (UHF) band [867.5-868 MHz]. The proposed RFID antenna is designed on a Kapton substrate with dielectric constant 3.5 and loss of 0.0027. It consists of two opposite meander line antennas of 8 turns each one and interconnected to ALIEH H3 microchip associated to two slotted patch’s with a global size 105×25×0.1 mm<sup>3</sup>. The proposed RFID antenna is designed and simulated using CST MWS as an electromagnetic solver. The results of the simulation show a return loss of -22.64 dB at 868 MHz, a reading distance of around 5 m, and a simulated input impedance of the antenna are 31.72+j109.68 Ω at the operating frequency 868 MHz.</p>

High gain and high-efficiency compact resonator antennas based on spoof surface plasmon polaritons

Abstract We proposed a high gain high-efficiency compact metallic resonator antenna operating at even-mode meander line spoof surface plasmon polaritons (MLSSPPs). The high radiation efficiency is caused by the bulk of fields crowded in lossless air near the antenna rather than in lossy dielectric as in conventional dielectric resonator antennas (DRAs). The proposed antenna also exhibits compact size because of its high effective refractive index. A reliable equivalent circuit model is proposed for the design of the resonator antenna with basic mode of half wavelength resonant mode. As an example, a meander-line SSPP antenna is designed, fabricated and measured. Both the simulated and measured results show the advantages of high efficiency and compact volume. In addition, the antenna achieves higher gain and wider relative bandwidth per wavelength cube volume compared with its counterparts. This method provides a good alternative for designing DRAs.

Investigating the influence of additional ground conductors influence on the characteristics of stripline devices with modal decomposition based on a meander line turn

Investigating the influence of additional ground conductors influence on the characteristics of stripline devices with modal decomposition based on a meander line turn

Using Reflections in a Meander Line Turn of Two Segments for Suppressing UWB Excitations

Using Reflections in a Meander Line Turn of Two Segments for Suppressing UWB Excitations

PDMS-Based U-Slotted Patch and Meander Line Antennas for Search and Rescue Applications

This study focuses on the development of a low-profile meander line-based antenna as well as a U-slotted patch antenna that was built specifically for the requirements of search and rescue operations. Both of these antennas serve as the primary focus of this investigation. Both the meander line antenna and the U-slotted patch antenna that are being considered are planned to be constructed on a substrate that is made of polydimethylsiloxane (PDMS). PDMS is selected because of its desired features, which include its durability, flexibility, resistance to water, and adaptability for deployment in demanding environmental circumstances. The usage of the search and rescue application necessitates the operation at a relatively lower frequency of 406 MHz, which in turn necessitates the utilization of antennas that have a longer electrical length. As a consequence of this, these antennas have a propensity to have larger physical dimensions. In order to circumvent the problem, it is possible to make use of U-Slotted Patch and Meander Line Antennas, which will result in a smaller dimension. This was proved by the results of the simulation, which showed that the antenna functioned at a central frequency of 406 MHz, displaying a bandwidth of 40.5 MHz for the U-slotted patch antenna and 67.49 MHz for the meander line antenna, respectively. Concerning the two antennas, these bandwidths were equivalent to a fractional bandwidth percentage of 9.9% and 16.55%, respectively, when evaluated at -10 dB of the reflection coefficient.

Design of Flexible and Dual Band Antenna for Vehicular Communication

The antenna with bowtie and meander lines shaped elements for the vehicular communication in this paper. The dimensions of the proposed antenna are 40.5*91.5*0.1. The substrate used in this antenna is polyamide substrate with a permittivity of 4.3. The implemented antenna is operated at cellular (975MHz) and C-V2X (5.9GHz) band. The efficiency of this proposed antenna is 99.5%. This paper describes the design of antenna with high efficiency vehicular roof mounted for V2V communication system used for ubiquitous intelligent systems. To enhance the connectivity among vehicles by providing seamless communication and to reduce initial access time using high performance antenna systems is the purpose of the ubiquitous intelligent systems. V2V communication efficiency depends on the antenna efficiency used for ubiquitous intelligent systems. We are proposing this antenna to increase the performance of the antenna by enhancing efficiency.

A compact meander flexible UHF tag for industrial applications

The objective of this paper is to introduce a novel design for a flexible Ultra-High Frequency tag (UHF tag) through the utilization of the meander line technique (MLA) and loop antenna method. The primary goal is to achieve a compact UHF tag operating at 868 MHz. The physical dimensions of the UHF tag are 110×12×0.1mm3. The proposed UHF tag is manufactured using the inkjet printing method on a polyamide substrate featuring a relative dielectric constant of 3.5, a tangent loss of 0.0027, and a height of 0.0508 mm. Through electromagnetic simulation and validation, the functionality of the proposed UHF tag covers the UHF band ranging from 854.57 to 883.89 MHz, with a bandwidth of 29.32 MHz. The reflection coefficient at 868 MHz is approximately -22.46 dB. The simulated gain measures 1.79 dBi, while the theoretical read range is estimated at 5 m. The UHF tag is produced using silver ink with a thickness of 0.05 mm and assembled using an anisotropic conductive paste (ACP). Subsequent to electromagnetic simulation, the UHF tag’s performance is confirmed through a reading test conducted with a radio frequency identification (RFID) base station. The results are consistent with the theoretical expectations, showcasing a commendable read range of 5 m. To safeguard the UHF tag from challenging environmental conditions, it is enclosed within a polyethylene film (PE). Following encapsulation, the read range decreases to 3 m, making it suitable for RFID applications requiring mid-range capabilities.

Reconfigurable meander line dipole antenna based on two rectangular defected ground structure

Reconfigurable meander line dipole antenna based on two rectangular defected ground structure

Miniaturized 3‐bit frequency‐reconfigurable monopole antenna with a meander line

AbstractA novel 3‐bit frequency‐reconfigurable antenna (FRA) with miniaturized dimensions is realized with a meander line. The frequency reconfiguration of the antenna is achieved by introducing N Radio Frequency (RF) PIN diodes into the meander line. The related parts of the meander line with different lengths are bypassed or included into the antenna by switching on or off the diodes, resulting in 2N switchable size lengths of the antenna and equally spaced operating frequencies. A 3‐bit reconfigurable meander‐line antenna (N = 3) is designed, and the simulated and measured results agree well. The antenna provides 8 (23) independent and switchable states, with the operating frequencies covering a wide switchable frequency range from 1.04 to 1.51 GHz and the working bandwidths varying from 80 to 150 MHz. The number of working bandwidth states is maximized, considering the number of switches used. Moreover, the results reveal an acceptable peak gain of 1.59 dBi in terms of the miniaturized total dimension of 0.17 λg × 0.07 λg (λg is the guided wavelength at the lowest working frequency), which is more compact than several published FRAs.

Frequency Tunable PIFA Design Based on Meander Line Elements

Bu çalışmada, WLAN ve WiMAX uygulamaları için elektriksel olarak frekansı ayarlanabilir yeni bir düzlemsel evrilmiş-F anten (DEFA) tasarımı önerilmektedir. 30 × 25 × 10 mm3 boyutlarındaki antenin ana radyatörü simetrik olmayan kıvrımlı şerit elemanlarından oluşmakta ve frekans cevabı bu elemanlar arasında optimum konumda kullanılan bir PIN diyotu aracılığıyla dinamik olarak ayarlanabilmektedir. Sayısal tasarımı Ansoft-HFSS ve CST Microwave Studio benzetim yazılımları aracılığıyla gerçekleştirilen antenin prototip üretimi de gerçeklenerek, diyotun açık/kapalı durumları için geri dönüş kaybı ölçümleri alınmıştır. Önerilen anten diyotun kesim durumunda WiMAX bandında tek bent rezonans gösterirken, iletim durumunda 2.4 ve 5.2 GHz WLAN bantlarında rezonansa gelmektedir. Ayrıca E ve H-düzlemleri için ilgili frekans bantlarında oldukça düzgün ışıma karakteristikleri sergileyen antenin mutlak kazanç değerleri 2-4 dBi arasındadır.

Compact ACS-fed MIMO antenna with dual-band notch characteristics for UWB applications

Abstract An ultra-wideband (UWB) and compact-size four-port multiple input multiple output (MIMO) antenna with a footprint of 34 mm × 34 mm fed by an asymmetric coplanar strip (ACS) is investigated. The proposed antenna is composed of four orthogonally placed identical modified elliptical-shaped radiators and achieves an impedance bandwidth of 3.4–12.2 GHz. By etching two inverted L-shaped slots in the radiator element, WLAN band and X-band are rejected in the operating communication range. Because of the usage of a meander line decoupler, the isolation enhancement at the 8–12 GHz band is achieved and the isolation is more than 18 dB for most of the UWB range. The performance of the proposed antenna is studied in terms of isolation between each port, radiation pattern, current distribution, gain, envelope correlation coefficient, diversity gain, and total active reflection coefficient. The compact size and reduced complexity make the proposed design highly suitable for portable devices.

Miniaturization and Bandwidth Enhancement of Fractal-Structured Two-Arm Sinuous Antenna Using Gap Loading with Meandering

A sinuous antenna is a frequency-independent antenna known for its wide bandwidth and consistent gain, which makes it valuable in broadband applications such as ultrawideband (UWB) radar and ground-penetrating radar (GPR). However, sinuous antennas tend to be rather large. Consequently, numerous studies have explored miniaturization methods, with the gap-loading method emerging as a prominent approach. Unfortunately, it is still difficult to achieve broad bandwidths for conventional miniaturized sinuous antennas. In this paper, we use a novel approach incorporating a meander shape into the sinuous curve and employing gap loading with meandering. This innovative technique results in the development of a fractal-structured two-arm sinuous antenna characterized by an ultra-compact size and significantly expanded bandwidth. Adding a meander line in the outermost part maximizes the capacitance, thereby enhancing the gap-loading effect and minimizing the overall size of the sinuous antenna. In addition, the introduction of an inner meander line increases the inductance, contributing to a further expansion of the antenna’s bandwidth. For example, the electrical length of the antenna without the meander line is 0.552 × 0.552 × 0.052 λg3, while the electrical length of the antenna with the meander line is only 0.445 × 0.445 × 0.036 λg3, i.e., 19.4% smaller. The antenna lacking the outermost meander line exhibits a 10 dB impedance bandwidth, spanning from 0.74 to 10.53 GHz. In contrast, the antenna featuring the outermost meander line has a 10 dB impedance bandwidth, extending from 0.51 to 10.72 GHz, which results in a remarkable enhancement in the fractional bandwidth (by 8.1%). Hence, the proposed antenna design is a good candidate for broadband applications that require miniaturization.

Generation of ultrashort Rayleigh wave pulses using the combination of temporal and spatial pulse compression technique

Rayleigh waves generated by electromagnetic acoustic transducers (EMATs) have been widely used in nondestructive testing and evaluations. To improve the signal to noise ratio (SNR) and spatial resolution of Rayleigh waves simultaneously, the combination of temporal and spatial pulse compression (TSPC) technique is proposed. By analyzing the topology diagram of the typical pulse compression technique, a frequency modulated signal acts as the stretcher and a wavelength modulated meander line coil acts as the compressor. Experimental results indicate that the ultrasound fields of Rayleigh waves using the proposed TSPC technique show a spike shape in the spatial domain. Compared with the typical meander-line coil EMATs, the TSPC technique shows significant improvement of the generated Rayleigh waves. The SNR has increased by 12 dB while the main lobe width has decreased by about 98%.

CRLH‐TL‐loaded metamaterial antenna with frequency band and polarization reconfigurability

SummaryIn this communication, an asymmetric co‐planar waveguide (ACPW)–fed composite right–left‐handed transmission line (CRLH‐TL)–based frequency band and polarization reconfigurable antenna (RA) is presented. The reconfigurability is achieved by using a PIN diode. When the diode is in OFF state, meander line works as part of ground. Hence, the antenna is like a circular patch antenna working at 5.15 GHz. In the ON state, the antenna works as a CRLH‐TL‐based antenna with an additional lower band resonating at 2.45 GHz. The antenna also has circular polarization (CP) property. The lower 2.4 GHz band is covering for IEEE 802.11 b/g/n/ax/be applications, whereas the higher band is covering the WiFi bands of IEEE 802.11a/h/n/ac/ax/be applications with CP radiation (upper band). This antenna is effective in a scattering environment such as in urban areas and indoor communication.

Highly sensitive RF sensor based on microstrip meander line for measuring microfluidics dielectric properties of alcohol–alcohol mixtures

Abstract In this paper, a radio frequency sensor for measuring microfluidics dielectric properties is designed based on microstrip meander line. The meander sensor replaces the straight transmission lines with meander transmission lines in the part of the half-wavelength path difference to improve the sensitivity of the sensor and reduce its size. According to the experimental results, the meander sensor based on the meander line has higher accuracy and a lower relative error than the straight sensor in measuring methanol–ethanol mixtures with different molar fractions. The relative error measured by the meander sensor after calibration with an adjustable cavity is less than 1%. It is easier to detect the very slight variation in dielectric properties brought about by microfluidics. The detection technique can be further applied for the accurate detection of dielectric properties of valuable biological samples, providing a more concise and convenient way.