Band-notched Ultra-wideband Antenna Research Articles

Two new single/multi-objective multi-strategy algorithms for the parametric estimation of dual band-notched ultra wideband antennas

This article introduces a novel single objective and a multi-objective multi-hybrid naked mole-rat (moIGDN) algorithm optimization techniques for solving numerical benchmarks and electromagnetic engineering problems. The hybridization was introduced to overcome the basic naked mole-rat algorithm’s (NMRA’s) local optima stagnation and poor exploration problems. The global exploration search equations of INFO, gazelle optimization algorithm (GOA), and dwarf mongoose optimization algorithm (DMO) have been added into the NMRA’s worker phase. Additionally, five mutation operators have been introduced for parametric enhancements and adaptations. For single-objective performance evaluation, three benchmark datasets namely classical benchmark, CEC 2014, CEC 2017, and CEC 2022 have been analysed. A comparison with JADE, SaDE, CMA-ES, success history based DE (SHADE), fractional-order calculus-based FPA (FA-FPO), LSHADE-SPACMA, NL-SHADE-LBC, evolutionary algorithms with eigen crossover (EA4eig), S-LSHADE-DP, L-SHADE-RSP-MID, EBOwithCMAR, LSHADE-EpSin among others. Apart from that, the proposed moIGDN algorithm was utilized to optimize the design of two electromagnetic multi-objective printed monopole antennas categorized as basic ultra-wideband (B-UWB) and dual band-notched ultra-wideband (DBN-UWB) antennas. Simulations have been performed by using the EM-MATLAB optimization interface with two objective functions: trying to minimize pass-band signal reflection and maximizing antenna gain, by mapping solutions to the Pareto-front boundary in the objective space. The best obtained antenna structure had an impedance bandwidth of 2.92–11.96 GHz (fractional bandwidth of 122%), efficient band-rejection characteristics for the WI-MAX (3.3 GHz–3.7 GHz) and WLAN (5.15 GHz–5.85 GHz) bands, and a compact geometry. Based on simulation results, moIGDN is found to be effective and can be utilized to solve complex wireless communication and advanced engineering optimization problems.

Sensitivity enhancement of an antenna sensor by using sextuple notch bands for application in cancer detection

In this study, a sextuple band-notched ultra-wideband (UWB) antenna sensor with slots in the feedline and parasitics is proposed. This is used for cancer detection in breast and skin phantom. The antenna sensor operates a bandwidth of 2.45–16 GHz. The dielectric properties of malignant cells are completely distinct from healthy cells, EM waves passing through the cells recognize a malignant. S11 parameters of the antenna are analyzed with the help of a Vector Network Analyzer (VNA) after placing the antenna on the phantoms. Further, the statistical machine learning concept of Principal Component Analysis (PCA) is utilized for more vivid detection of malignant cells. The bands WiMax (2.8–3.4 GHz), radio astronomy (4.75–5.8 GHz), satellite communication (6.7–7.5 GHz, 9.2–10.9 GHz and 12.95–13.55 GHz) and SHF band (15.43–15.63 GHz), create interferences within the UWB spectrum. The interfering bands are removed by slot loading and parasitics. Thus, the sensitivity of the antenna sensor improved.

Development of a Triple Band Notched UWB Antenna

In this paper, a microstrip line-fed rectangular-shaped ultra-wideband (UWB) antenna offering triple-band notch characteristics is proposed. The notching was done primarily to provide rejection for Wi-Max (3.3-3.7 GHz), WLAN2 (5.15-5.825 GHz), and ITU (8.025-8.4 GHz) through the combination of slots and a modified electromagnetic band gap (M-EBG). The antenna was simulated using HFSS and CST modelling tools. The antenna was able to notch three frequencies from narrow band communication systems (Wi-Max, WLAN2, and ITU), causing interference within the UWB band. The gain of the system over the operating frequency, the current distributions, and the impedance covered were studied to assess the effectiveness of the antenna. The proposed antenna is simple and compact, with a total antenna size of 19 mm by 24 mm and a wide bandwidth (3.2 to 12.5 GHz). Satisfactory results have been obtained when its performance was analyzed. A stable radiation characteristic is observed with a radiation efficiency of 94% when operating at a UWB resonant frequency of 6.85 GHz with a total gain between -10 dB and 5 dB within the range of the frequency band of 3.2 to 12.3 GHz.

Modal Analysis, Inverse-Design, and Experimental Validation of Bandwidth-Controllable Suspended Patch Antennas Loaded With Cylindrical Anisotropic Impedance Surfaces

In this article, bandwidth-controllable suspended patch antennas (SPAs) loaded by anisotropic impedance surfaces (AISs) are proposed. A highly efficient yet accurate semianalytical modal expansion method (MEM) is developed for calculating the input impedance and radiation properties of the proposed antenna, which greatly reduces the simulation time and consumed memory compared to a commercial full-wave solver. The MEM is further utilized by coupling it with a genetic algorithm for effectively performing inverse-design, i.e., optimizing AIS-loaded SPAs with different predefined frequency responses. Three proof-of-concept antenna examples are designed, fabricated, and characterized, including an ultrawideband (UWB) antenna, a dual-wideband antenna, and a band-notched UWB antenna. The operating principle is illustrated by investigating the resonant modes of the AIS-loaded SPAs. The measured results of the three antennas exhibit good agreement with theoretical predictions, demonstrating that all three antennas have vertically polarized conical patterns in the E-plane and omnidirectional patterns in the H-plane with a cross polarization of smaller than −15 dB in their respective operational frequency band(s). The good performance demonstrates that the proposed AIS-loaded SPAs are promising candidates for broadband and multiband communications.

Parametric Study and Analysis of Modified Electromagnetic Band Gap in Frequency Notching of Ultra-Wide Band Antenna

This paper presents parametric study of dual band notch ultra wideband (UWB) antenna using modified electromagnetic band gap. The Electromagnetic Band Gap (EBG) comprises of two strip patched and an edge-located via with respect to ground for dual notch band. The study was presented in order to have an improved knowledge of EBG characteristics and its effect on the notching band of a small squared ultra wideband antenna of size 24 by 31 mm2 dual band notch using HFSS software. The antenna operates within the return loss (s11< -10dB) 3.2 to 12.3 GHz. The simulation results show that the notched band between 4.57 – 4.99 GHz and 7.96 – 8.32 GHz corresponding to WLAN and ITU respectively was achieved. The effect of gap distance between the field line and EBG was demonstrated as well and the position of via with respect to the ground as a means for notched band centre frequency tuning. The antenna could be considered a good candidate for any UWB applications that must avoid narrow band interference. The research gives ideas on the best placement position of EBG structure along field line in UWB antenna frequency notching technique.

EBG and SRR Loaded Triple Band Notched UWB Antenna

A compact triple band notched ultra-wideband (UWB) monopole antenna is presented in this paper. Split Ring Resonator (SRR) structure is exploited in various forms like Complementary Split Ring Resonator (CSRR), Split Ring Resonator Pair (SRRP) and CSRR on Electromagnetic Band Gap (EBG) structure to produce triple band notched characteristics in UWB spectrum. The proposed antenna produces triple band notched functions with integration of all three types of SRR on primary antenna. The parametric analysis of each form of SRR is presented along with their current distribution effects on triple band notched antenna. The proposed antenna prototype is fabricated and measured results are also compared with simulated one to understand the discrepancies. The measured and simulated results are presented to investigate the band notching characteristics of suggested antenna in terms of VSWR and radiation characteristics.

Design and analysis of UWB antenna with quintuple band-notched and wide-band rejection characteristics

AbstractIn this study, a compact ultra-wideband (UWB) antenna with quintuple band-notched and wide-band rejection characteristics is studied. The proposed antenna mainly consists of a rectangular radiating patch, a microstrip feeding line, and a modified rectangular ground plane. The quintuple band-notched functions with narrow stop bands are achieved at WiMAX (3.3–3.7 GHz), WLAN (5.15–5.35 GHz and 5.725–5.825 GHz), C-band IEEE INSAT/super-extended (6.7–7.1 GHz) by using three modified inverted U-shaped slots and two symmetrical rectangular slots on the radiating path. Each stop band formed in the UWB antenna can be adjusted independently, and deep reflection zeros are formed between the adjacent stop bands. The formation of reflection zeros improves the band-edge selectivity of the stop band, and the notch characteristics are more prominent. To further study the wide stop band (C-band and X-band) with good selectivity characteristics, a pair of L-shaped open slot is added to the edges of two rectangular slots. Additionally, a pair of modified Rho-shaped resonators is located near the feeding line to realize band-notched characteristic at ITU service bands (8.025–8.4 GHz), thus a quintuple band-notched UWB antenna is achieved. The shape factor (ratio of the −3 dB bandwidth to the −10 dB bandwidth) of the wide stop band is 0.56, which indicates that the antenna has excellent band-edge selectivity. To verify the performance of the proposed design, both the time-domain and the frequency-domain characteristics of the antenna have been studied and analyzed. The simulated and measured results verify the design as a good candidate for various portable UWB applications.

Quadruple Band-Notched Compact Monopole UWB Antenna for Wireless Applications

A printed quadruple band-notched ultra-wideband (UWB) antenna characteristic is presented. The designed UWB antenna has a size of 32 mm × 30 mm × 1.6 mm and covers an impedance bandwidth off 2.9–14.5 GHz for the entire frequency band. The entire frequency band maintains voltage standing wave ratio (VSWR) <2, except at WiMAX (3.1–3.6 GHz), WLAN (4.92–6.12 GHz), downlink of X-band for satellite communication systems (7.5–8.4 GHz), and X-band (10.2–11 GHz). By inserting a pair of L-shaped slots into the radiating element, a H-shaped resonator and rectangular split-ring resonators are closely arranged to the microstrip feed-line, alongside the measured impedance bandwidth of 129%. The fabricated antenna radiation pattern and return loss is presented.

Twelfth mode on-demand band notch UWB antenna for underlay cognitive radio

A wide-slot ultra-wideband (UWB) antenna with on-demand band rejection characteristics that can serve underlay cognitive radio is presented in this paper. This antenna is designed to work in twelve operation modes; one to cover the whole UWB while each of the rest modes excludes one or more of the ranges that are allocated for Worldwide Interoperability for Microwave Access (WiMax), C-band, wireless local area network (WLAN), X-band and International Telecommunication Union (ITU) in a single, dual, triple, quad or penta band rejection state. A spiral shape slot in the patch and three slots mainly based on half-circular structures in the ground plane are the means to create the desired frequency notches. A positive-intrinsic-negative (PIN) diode across each of these slots is used to enable/disable band(s) rejection process. Configuration of the proposed antenna to the desired mode of operation is decided by the state of its four PIN diodes. This work is simulated by computer simulation technology (CST) v.10. It’s S11, voltage-standing-wave-ratio (VSWR) and realized gain results when combined with antenna's 25x25x0.8 mm3 compact size and the large number of modes and states, all ensure its capability to eliminate or reduce the interference within the targeted bands and hence being suitable for the applications of underlay cognitive radio.

Effect of parametric enhancements on naked mole-rat algorithm for global optimization

Naked mole-rat algorithm (NMRA) is a new swarm intelligence technique based on the mating patterns of NMRs present in nature. The algorithm though is very simple and linear in nature but suffers from poor exploration during the initial stages and poor exploitation towards the end. Thus to overcome these problems and estimate the effect of basic parameters of NMRA, six new inertia weight strategies and five new mutation operators have been employed. After careful investigation, a new Levy mutated NMRA (LNMRA) is proposed. The new algorithm employs combined properties of inertia weights and mutation operators altogether. For performance evaluation, the proposed algorithms are subjected to variable initial population and dimension sizes and testing is done on CEC 2005, CEC 2014 benchmark problems and real world optimization problem of dual band-notched ultra-wideband (UWB) antenna design. Experimental and statistical results show that the proposed LNMRA is better with respect to other algorithms under comparison.

Design and Analysis of Dual Band-Notched UWB Antenna Using a Slot in Feed and Asymmetrical Parasitic stub

A novel elliptically slotted antenna (ESA), with two notched bands for Ultrawideband (UWB) applications, is presented. The ESA comprises of an elliptically slotted radiator with a beveled defected ground structure (DGS) for achieving UWB bandwidth ranging from 3.42 to 11.79 GHz (110%) for VSWR< 2. Two rejected bands at WLAN (5.02–5.97 GHz) and down link of X- band (7.23–7.72 GHz) applications are obtained by etching S-shaped slot in the microstrip feed line and an asymmetrical C- shaped parasitic stub above the DGS, respectively. The ESA is printed on FR-4 substrate with a compact size of 24 × 28 and with a stable gain fluctuation from 2 to 4.08 dBi. A good matching, achieved in-between tested and simulated results, makes ESA to be a suitable candidate for WLAN/X-band-notched UWB applications.

Switchable triple band-notched UWB antenna modelling for interference rejection from dual WiMAX bands and satellite C-band service

A triple band-notched monopole antenna with reconfigurable characteristics is designed and investigated in this study for implementation in ultra-wideband (UWB) systems. A conventional rectangular monopole antenna is intended first to accomplish UWB performance characteristics. Further, to obtain triple notched characteristics, three U-shaped slots are etched on the rectangular radiating surface of the antenna. A wide frequency bandwidth ranging from 2.13 GHz to 10.50 GHz with three notched bands operating at 2.65 GHz (2.49–2.82 GHz), 3.43 GHz (3.18–3.68 GHz), and 4.08 GHz (3.93–4.22 GHz) have been successfully realized. By integrating three PIN diode switches, total eight reconfigurable states of operations have been realized in the UWB spectrum. A thorough analytical investigation along with the comparison of simulated and measured performances for the proposed antenna has been presented to manifest the applicability in practical systems. The antenna structure can be successfully implemented for rejecting interferences from dual WiMAX bands along with C-band fixed satellite communication systems, respectively.

A Systematic Methodology for the Time-Domain Ringing Reduction in UWB Band-Notched Antennas

Various ultrawideband (UWB) band-notched antennas are developed to avoid interference between UWB and other nearby narrow frequency bands that falls within the UWB spectrum. However, all band-notched UWB antennas developed generate ringing in the time domain, and a great amount of distortion is present in transmitted (or received) UWB pulses. The distortion level is dependent on band-notching strength and bandwidth, and it highly degrades the performance of the UWB system that is based on short pulses. This letter investigates time-domain ringing effect in UWB band-notched antennas and proposes a solution for its reduction. The proposed technique is verified through simulation and validated using measurements. The proposed technique will have key importance in impulse UWB radars.

Bandwidth Enhancement of a Wide Slot Antenna Using Fractal Geometry for UWB Application with Multiple Notched Bands

In this paper a combination of rectangular and elliptical fractal geometry is applied on a regular hexagonal wide slot antenna fabricated using a FR4 substrate to obtain ultra wide band (UWB) operation. The bandwidth enhancement of the wide slot antenna due to this fractal curve is studied in a step by step manner and the corresponding mathematical analysis is also presented. The comparison of the proposed fractal geometry with the existing fractal geometries is also exhibited. Multiple input multiple output performance of the proposed UWB antenna is also analysed. Two pairs of L-shaped slots are etched on the ground plane and a metallic ring is inserted inside the slot to produce triple band notch characteristics at 3.98 GHz, 5.56 GHz and 7.94 GHz. These three notch bands can avoid interference with existing WIMAX, downlink of C-band satellite communication, WLAN and uplink of X band satellite communication. The proposed band notched UWB antenna exhibits acceptable radiation characteristics with satisfactory gain, high radiation efficiency and constant group delay in the operation band.

Design of a dual band-notched UWB antenna and improvement of the 5.5 GHz WLAN notched characteristic

ABSTRACTA novel dual band-notched ultra-wideband (UWB) planar antenna with improved characteristic in 5.5 GHz WLAN notched band is presented. Two kinds of L-shaped slots are inserted in the radiator in order to obtain the dual notched characteristics. A separated strip is added in the middle of the U-shaped radiator for further improving the performance. The antenna has a measured impedance bandwidth of 3.1–11.0 GHz with VSWR < 2, while it has dual notched bands of 3.4–4.0 GHz and 4.9–6.0 GHz. Besides, the equivalent circuit model, transmission line model and transfer function are also studied to investigate the band-notched performance of the proposed antenna.

Octagonal nut shaped monopole UWB antenna with sextuple band notched characteristics

A printed octagonal nut shaped ultra-wideband (UWB) monopole antenna with sextuple band rejection characteristics is proposed and investigated. Improved frequency selectivity of the rejection bands can be achieved by employing hook shaped, split P-shaped open ended stub resonators along with open ended meandered slot resonator pair, Meandered T shaped stub, rectangular dual split ring conductor backed plane and spiral shaped defective ground structure exhibit band rejection of 3.3–3.64 GHz (9.79%), 5.1–5.35 GHz (4.97%), 5.62–5.96 GHz (5.87%), 7.28–7.68 GHz (5.21%), 7.8–8.21 GHz (5.12%) and 9.23–9.77 GHz (5.68%) to mitigate the possible interferences of WiMAX, lower WLAN, upper WLAN, X-band satellite downlink, ITU-8 GHz and radio navigation (RN) band. Sharpness and the tuning of the individual notched band can be easily controlled by adjusting the dimension of the corresponding band notched element. Besides, a lumped element equivalent circuit model has been evaluated by comparing with the response of proposed band notched UWB antenna that exhibits highly selective rejection bands. Moreover, radiation patterns, peak gain and time domain behavior of the proposed antenna are also investigated to assess its suitability in UWB communication.

Multimode resonator‐assisted dual band notch UWB antenna with additional bluetooth resonance characteristics

A compact planar integrated ultra-wideband (UWB) and Bluetooth antenna are presented in this study. The basic radiator is circular in shape with a wide slit in it to accommodate a space optimised T-shaped stub for Bluetooth frequency band. The proposed antenna is CPW-fed with bevelled ground planes for the purpose of improvement in input impedance matching. A novel multimode resonator at the back of the substrate is responsible for the creation of two-notched band at 5.5 and 8.1 GHz. The antenna exhibits an operational bandwidth of 3.–12 GHz for UWB application. The proposed antenna also has Bluetooth resonance characteristics at 2.4 GHz. The overall size of the antenna is 14 × 32 × 1.59 mm 3 . The antenna has a peak realised gain of 4 dBi and a constant group delay. The radiation pattern is also stable throughout the operational bandwidth. A fabricated prototype is developed and tested. Results obtained from electromagnetic simulation, equivalent circuit model, and measurement are in good agreement.

Compact UWB Band-Notched Antenna with Integrated Bluetooth for Personal Wireless Communication and UWB Applications

A compact band-notched UWB (Ultra-Wide Band) antenna with integrated Bluetooth is developed for personal wireless communication and UWB applications. The antenna operates at the UWB frequency band (3.1–10.6 GHz) as well as Bluetooth (2.4–2.484 GHz), with band-notch characteristics at the Wireless Local Area Network (WLAN) frequency band (5–6 GHz). A new technique of integrating Bluetooth within a UWB band-notched antenna is developed and analyzed. The UWB frequency band is realized by utilizing a conventional cylindrical radiating patch and a modified partial ground plane. The Bluetooth band is integrated using a miniaturized resonator with the addition of capacitors. Further, to mitigate the interference of the WLAN frequency band within the UWB spectrum, a conventional slot resonator is integrated within the radiator to achieve the task. The antenna is designed and fabricated, and its response in each case is provided. Moreover, the antenna exhibits a good radiation pattern with a stable gain in the passband. The present antenna is also compared to state-of-the-art structures proposed in the literature. The miniaturized dimensions (30 × 31 mm2) of the antenna make it an excellent candidate for UWB and personal wireless communication applications.

A Triple Band-Notched UWB Antenna Using Folded Resonators

Abstract A triple band-notched ultra-wideband (UWB) monopole antenna etching novel folded resonator on the radiating patch, ground and between the feeding-line, is presented in this paper. The tri-rejection bands are 5.1–6.1 GHz, 7.6–8.8 GHz and 10.1–10.8 GHz which have covered bands of WLAN and ITU 8 GHz. To analyze the principle of proposed antenna, the simulation of parametric study and distribution of surface current are carried out. The size of antenna is 32 mm×19 mm×1 mm. And the test results are in good agreement with the simulation, which indicate that the antenna is promising for UWB system.

A Frequency Reconfigurable Band-notched UWB Dielectric Resonator Antenna with a Wide-tuning Range for Cognitive Radio Systems

A new reconfigurable band-notched ultra-wideband (UWB) dielectric resonator antenna (DRA) has been designed and fabricated for cognitive radio (CR) applications. The UWB antenna design comprises a dielectric resonator as a radiation element, a ground plane, and a microstrip feed line. The frequency band’s rejection mechanism is achieved by cutting two slots and adding an L-shaped stub on the ground plane. The reconfigurable function is created by PIN diode switches to change the current distribution path on the ground plane. A preliminary model of the DRA was fabricated, and its efficiency was verified. The proposed antenna occupies an area of 40 × 40 × 7.3 mm. The simulated and measured results have demonstrated suitable radiation patterns attained by the proposed antenna, which operates within the UWB frequency range of 3–11 GHz. Moreover, the antenna has shown an ability by rejecting switchable bands to achieve the WiMAX (3.2–3.65 GHz), WLAN 5 GHz (4.8–6 GHz), and ITU 8 GHz (8–8.3 GHz). Also, this antenna can be operated as dual and triple band-notched antennas.