Patch Resonator Research Articles

A compact low-profile substrate integrated waveguide wearable filtenna for 5G communication

We have proposed the design and synthesis of a compact, low-profile, flexible substrate integrated waveguide (SIW) wearable filtering antenna (filtenna) for 5 G communication, along with two parasitic resonator patches. We initially used a half-mode rectangular-shaped substrate-integrated (HMRSI) cavity as a resonating patch to minimize circuit size. The HMRSI cavity is located in close proximity to two parasitic truncated corner patches that serve as both the radiator and the final stage resonators, thereby optimizing filtering performance and expanding the operating bandwidth. The interaction of the parasitic patches with the HMRSI cavity produces one radiation null at the upper band-edges, while the corner truncation and notching on the parasitic patches with defected ground creates the other, enhancing the roll-off rate. Typical filter synthesis technology guides the design of the antenna. We have manufactured and measured an optimized prototype. The proposed flexible filtenna demonstrates excellent out-of-band selectivity, and its measurement aligns well with simulated ones, achieving an 8.2% fractional bandwidth (FBW), a maximum realized gain of 6.1 dBi, and a flat passband gain response. The proposed filtenna has also studied the human body and achieved a low specific absorption rate (SAR), which enables it to be an on-body wearable filtenna.

A General and Effective Design Method for Compact Bandpass Filters With Extensible Orders/Channels on a Modified Patch Resonator

A General and Effective Design Method for Compact Bandpass Filters With Extensible Orders/Channels on a Modified Patch Resonator

Design of wideband bandpass frequency selective surface based on the patch resonators and substrate integrated waveguide cavities

Design of wideband bandpass frequency selective surface based on the patch resonators and <b>substrate integrated waveguide</b> cavities

A multiple resonant microstrip patch heart shape antenna for satellite and Wi-Fi communication

A multiple resonant microstrip patch heart shape antenna for satellite and Wi-Fi communication

Microwave Investigation of DMSO‐Doped PEDOT:PSS Patch Resonators Under Varying Relative Humidity

AbstractPoly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is a conductive polymer widely used in various microwave sensing components. Enhancing the efficiency of PEDOT:PSS‐based microwave structures relies on improving the polymer's conductivity, achievable by adding secondary solvents such as dimethyl sulfoxide (DMSO), which significantly boosts the electrical conductivity. However, the performance of DMSO‐doped PEDOT:PSS films in microwave regime requires investigations. Herein, patch resonators are fabricated using solution processing of aqueous dispersion of PEDOT:PSS doped with varying concentrations of DMSO from 0 to 8 wt.% to investigate their microwave behavior within the frequency range of 4.5–6.5 GHz. The PEDOT:PSS patch structures are implemented on a glass substrate and their resonant characteristics, including resonant frequency and amplitude, are studied in response to varying relative humidity (RH) levels ranging from 0% to 70%. The significant variations in the microwave responses are observed at the resonant amplitude, confirming the main impact of humidity on the conductivity of the films. According to the measured results, the 2 wt.% doped patch shows greater sensitivity to the changes to the RH in contrast to the 8 wt.% doped patches, where the response shows less sensitivity to the humidity variation. The results indicate that a lower percentage of DMSO enhances sensitivity to the humidity at the cost of increased electromagnetic loss in the resonant patch structures for humidity sensing applications.

Highly selective microstrip bandpass filters using dual-mode patch resonator loaded with short via

In this paper, highly selective dual-mode microstrip bandpass filters (BPFs) are presented utilizing novel square patch resonator loaded with short via and periodic metallic vias array. Characteristics of the patch resonator are studied, and a new nondegenerate dual-mode patch resonator operating with the second and third higher-order modes is proposed. A two-pole BPF based on one dual-mode patch cavity is analyzed, and two transmission zeros (TZs) are produced. To realize higher-order filtering responses, four-pole BPFs with two cascaded dual-mode patch resonators are proposed, and different cascaded methods of two dual-mode patch resonators by a λg/4 microstrip connecting line (MCL) are analyzed and compared to maintain high selectivity and small size. For the demonstration, two four-pole filters with the center frequency at 3.3 GHz and five transmission zeros is designed, fabricated and measured.

Compact, wide-stopband filtering power divider based on a single shielded circular patch resonator

Compact, wide-stopband filtering power divider based on a single shielded circular patch resonator

Wearable flexible Kapton-graphene electromagnetic sensors

This research is dedicated to the development of a new technology for a quick diagnosis of virial virus, using electromagnetic technology facilitated by either a Rectangular Patch Resonator (RPR) or a Wearable Flexible Sensor (WFS) designed for non-invasive viral disease detection, including Nano-virus, and macro-virus. These devices is tailored for a precise and non-invasive detection of a wide array of viruses. To enhance diagnostic precision, an electromagnetic sensor was meticulously explored and simulated, to be capable of detecting and identifying even the most minuscule viruses. Employing numerical modeling with a focus on the 10 GHz to 20 GHz frequency range. We hold a strong sense of optimism regarding this sensor's potential for non-invasive virus detection. Extensive simulations conducted throughout this study have underscored the WFS's selectivity across all viruses, boasting an exceptional limit of detection and sensitivity. Moreover, the WFS exhibited the capability to distinguish between varying infection percentages, each corresponding to a distinct reflection pattern.

Wideband dual‐polarized rasorber design with genetic algorithm synthesis

AbstractIn this letter, an 11 GHz centered wideband absorptive frequency selective surface (FSS) design is presented. The absorptive FSS is dual polarized, and it has wide transmission band and a wide absorption band at the lower frequency side of the transmission band. An octagon shape with parallel microstrips toward center connected with lumped element resistors at the edges is proposed for the resistive layer unit element. Also, a multilayer octagon patch and aperture resonator are proposed for the wideband bandpass layer. As an alternative design method, the unit element of resistive layer of absorptive FSS is synthesized by a genetic algorithm code successfully. Genetic algorithm synthesis provides straightforward synthesis process compared to conventional method. Designed absorptive FSS is manufactured and frequency response is measured with WR‐90 waveguide setup. The measurement result of 1 dB transmission bandwidth is between 9.43 and 12.50 GHz with a minimum insertion loss of 0.65 dB.

Design of compact balanced filters with wide DM upper stopband and CM rejection band based on semi‐circular patch

AbstractA new design approach to achieve compact size and high common‐mode (CM) suppression of balanced filters is proposed with two back‐to‐back microstrip semi‐circular patch resonators. In feeding structures, metalized via holes are adopted to vertically feed patches by differential pairs. Then, TM11 mode is excited and TM31 mode can be rejected, resulting in wideband differential‐mode (DM) harmonic rejection. Besides, with a slotline etched in the common ground plane, desired coupling strength can be achieved for a target bandwidth. Meanwhile, by virtue of the stacked structure, source‐load coupling can be easily introduced to generate transmission zeros close to the passband. With theory guidance, two balanced filter prototypes centered at 2.4 GHz are designed. Simulation and measurement results both indicate that proposed balanced filters exhibit high DM and CM performances as well as a compact size about 0.26λg × 0.53λg.

Size-Reduced Highly Selective Bandpass Filters Based on Dual-Mode Slow-Wave Patch Resonators

Size-Reduced Highly Selective Bandpass Filters Based on Dual-Mode Slow-Wave Patch Resonators

A dual-band wideband high-gain slot loaded microstrip patch antenna

This paper presents a dual-band, wideband, high-gain microstrip patch antenna applied to 5G band. The antenna consists of two rectangular radiation patches of different sizes, connected by a microstrip line and fed by a coaxial line. The dual-band is achieved by both rectangular radiation patches producing dual target resonant frequency points. This antenna provides the freedom for adjusting both resonant frequencies independently. To increase the antenna bandwidth, long slots are loaded at specific positions on each rectangular patch, allowing for dual-mode resonance radiation in each frequency band. This antenna operates in a shorted-edge resonant mode, where metal grounding holes added on the patch act as shorting walls. The size of a radiation patch is only half that of a standard resonant mode patch, making this antenna compact in size. Measurement results show that the antenna has an impedance bandwidth of 4.98–5.56 GHz (11.0%) and 5.74–6.62 GHz (14.2%), which completely cover the 5G band of China (5.18–5.52 GHz and 5.74–5.82 GHz). The maximum measured realized gain is 8.1 dB in the low-frequency band and 10.2 dB in the high-frequency band. This antenna offers advantages of dual-band operation, broadband, low-profile, high-gain, which is suitable for 5G band applications with targeted coverage requirements.

Dual-mode aperture-coupled patch resonator based dual-band higher-order frequency selective surfaces

In this article, a low profile aperture coupled dual band higher order bandpass frequency selective surface (FSS) is proposed. To begin, a simple patch resonator with an L-shaped truncated corner is theoretically examined such that two orthogonal modes can be activated at the same time. Following that, a combination of four identical L-shape truncated patch resonators with 90° rotation between two adjacent patches is developed and analyzed to avoid the reflection of cross-polarized produced by orthogonal modes. Further, by arranging two of such combination resonators placed back-to-back through aperture coupling metallic layer in the middle, a three layer single mode fourth order bandpass FSS is designed. The proposed bandpass FSS is twice the performance of traditional aperture coupled patch resonators (AC-PRs). It provides more flexibility at higher order filtering responses. To endorse the design concept, a dual-band fourth order bandpass FSS is simulated to initiate magnetic and electric coupling through the aperture metallic layer. Moreover, an equivalent circuit model for even and odd mode analysis is examined for the principle of operation. Finally, the proposed bandpass FSS is fabricated and tested in a vector network analyzer (VNA) setup. The measured and simulated results are compared and validated.

Multi-band terahertz metamaterial absorber composed of concentric square patch and ring resonator array

An equivalent circuit model (ECM) to analyze a single-layered graphene multi-band metamaterial absorber was developed. This absorber consists of concentric square patch and ring resonator arrays and operates in the terahertz (THz) region. To validate our analysis based on the ECM, we also conducted numerical simulations using the finite element method (FEM) within CST software. Additionally, we have explained the absorption behavior of the metamaterial using the coupled mode theory (CMT). This absorber design, with its single-layer structure, tunability, and triple absorption bands, offers promise for applications in THz devices and systems. Notably, it achieves an average absorption of 99% for three bands and the absorption reaches 100% in the frequency range of 4 to 6.5 THz. The correlation of ECM and CMT analyses with the FEM simulations validate the accuracy and the effectiveness of these simplified approaches in comprehending the resonant characteristics of the metamaterial absorber.

A low‐profile wideband microstrip patch antenna using double half‐mode resonances

AbstractThis paper presents a miniaturized broadband microstrip patch antenna with a simple geometry. The radiation patch of this antenna comprises two rectangular patches with slightly different sizes, one side of each patch is grounded by metal via‐holes. Two rectangular patches are connected by a microstrip line and fed by a single port. Two rectangular patches produce two closely resonant frequencies achieving broadband performance. This antenna operates on the resonant method of short‐circuiting on one side. Metal via‐holes act as a short‐circuit wall allowing each patch to operate in TM0.5,0 mode. The size of a 1/4 wavelength resonant patch is only half of a conventional microstrip antenna, the overall size of this antenna is almost as same as a conventional rectangular microstrip antenna, making it compact in size. The wideband is achieved by combining two radiating patches, resulting in stable radiation and flat gain. Measurement results show that the antenna has an impedance bandwidth of 4.355.10 GHz (15.8%) using a common dielectric substrate without air layer thickness additionally. The maximum measured realized gain is 4.61 dB. This antenna has advantages of wide bandwidth, low profile, flat gain and ease of manufacturing.

Ultra-narrowband light absorption with dual metamaterial ring resonator patches

In this paper, by utilizing ring resonator patches (RRPs) within metamaterial structures, a new approach is introduced to showcase the enhancement of light absorption in ultra-narrowband conditions. The utilization of a slit ring resonator enables the excitation of resonance modes characterized by standing wave patterns. The estimation of absorption peak positions can be reliably achieved through the application of the Fabry-Pérot (F–P) cavity model. Attaining absorption with a narrowband spectrum necessitates the simultaneous elimination of reflectance by achieving perfect impedance matching and the suppression of transmission via the metallic layer. The desirable characteristics of ultra narrow bandwidth can be preserved by changing the geometrical parameters of the RRPs. When working as a refractive-index sensor, the RRPs-based metamaterial showcases remarkable sensing capabilities owing to its consistent and reliable enhancement of ultra-narrowband absorption.

Synthesis Design of In-Line Pseudoelliptic SISL Bandpass Filter Employing Non-Resonating Mode in Low-Loss Patch Resonators

This paper presents a novel type of patch resonator suitable for the design of high selectivity in-line pseudoelliptic bandpass filters (BPFs) based on a substrate-integrated suspended line (SISL) platform. The proposed structure is a rectangular patch resonator that allows the propagation of the fundamental mode and high order modes. By controlling the position of input and output feedlines, the proposed resonators can provide both a reflection and a transmission zero simultaneously. Thus, a pole-zero pair can be produced (behaving as a singlet). The position of poles and zeros can be fully controlled by varying the position and orientation of the feeding lines. To verify the proposed concept, a detailed study about the behavior of the patch singlet and a validated third-order filter BPF with three TZs ( canonical BPF) located in the lower and upper passband is presented in this brief. The measured results exhibit an extended stopband with rejection better than 58 dB in the lower passband and 40 dB in the upper passband. The tested return losses and insertion loss are better than -15.7 dB and 1.31 dB, respectively.

An accurate probabilistic step finder for time-series analysis

Noisy time-series data—from various experiments, including Förster resonance energy transfer, patch clamp, and force spectroscopy, among others—are commonly analyzed with either hidden Markov models or step-finding algorithms, both of which detect discrete transitions. Hidden Markov models, including their extensions to infinite state spaces, inherently assume exponential—or technically geometric—holding time distributions, biasing step locations toward steps with geometric holding times, especially in sparse and/or noisy data. In contrast, existing step-finding algorithms, while free of this restraint, often rely on ad hoc metrics to penalize steps recovered in time traces (by using various information criteria) and otherwise rely on approximate greedy algorithms to identify putative global optima. Here, instead, we devise a robust and general probabilistic (Bayesian) step-finding tool that neither relies on ad hoc metrics to penalize step numbers nor assumes geometric holding times in each state. As the number of steps themselves in a time-series are a priori unknown, we treat these within a Bayesian nonparametric (BNP) paradigm. We find that the method developed, BNP Step (BNP-Step), accurately determines the number and location of transitions between discrete states without any assumed kinetic model and learns the emission distribution characteristic of each state. In doing so, we verify that BNP-Step can analyze sparser data sets containing higher noise and more closely spaced states than otherwise resolved by current state-of-the-art methods. What is more, BNP-Step rigorously propagates measurement uncertainty into uncertainty over state transition locations, numbers, and emission levels as characterized by the posterior. We demonstrate the performance of BNP-Step on both synthetic data as well as data drawn from force spectroscopy experiments.

Development of a Balanced-to-Balanced Filtering Power Divider Based on Right-Angled Isosceles Triangular Patch Resonator

Development of a Balanced-to-Balanced Filtering Power Divider Based on Right-Angled Isosceles Triangular Patch Resonator

Higher Order Bandpass Single and Dual Band Frequency Selective Surfaces With Aperture Coupled Patch Resonators

Higher Order Bandpass Single and Dual Band Frequency Selective Surfaces With Aperture Coupled Patch Resonators