Band Notch Research Articles

RETRACTED ARTICLE: Design and analysis of super wide band antenna and its notch band characteristics

RETRACTED ARTICLE: Design and analysis of super wide band antenna and its notch band characteristics

CPW-fed metamaterial inspired compact multiband antenna for LTE/5G/WLAN communication

Abstract In this work, metamaterial (MTM) inspired a compact CPW-fed antenna with triple operating band is proposed. A rectangular Split Ring Resonator (SRR) is unified in a circular slot of the polygon-shaped radiator in MTM inspired antenna. The antenna exhibits three operating band which are based on metamaterial characteristics of unit cell. The CPW-fed antenna is ensuing 10 dB impedance bandwidth varies from 2.28 to 2.38 GHz, 3.07 to 3.78 GHz, and 5.05 to 7.03 GHz, whereas notch band exist from 2.39 to 3.06 GHz frequency. Metamaterial behaviour leads into the bandwidth enhancement as well as miniaturization in lower operating band with electric length of 0.14λ 0 × 0.21λ 0. The antenna archives the peak gain of 1.49 dB at 2.34 GHz, 2.04 dB at 3.32 GHz, and 4.14 dB at 6.5 GHz frequency. The measured results authenticate the simulated outcomes and consequently the proposed antenna can be pertinent in LTE, WLAN, and 5G communications.

3D asymmetric super wide band (SWB) MIMO antenna system with band notch for antenna-in-package (A-I-P) applications

A UWB/SWB asymmetric 3D MIMO antenna with triple-band notch characteristics is proposed for Antenna-in-Package (A-I-P) applications. The proposed UWB/SWB radiators are placed on every side of a 3D cube-shaped polystyrene material. Each side of the cube contains two square UWB/SWB antennas with a hexagonal loop decoupling structure. Further, to reduce the mutual coupling between the radiators, each pair of antennas is placed asymmetrically on alternating sides of the cube block. The size of each pair of antennas is , and the overall size of the antenna is . The most significant properties of the antenna such as , , and radiation pattern are studied, Moreover, MIMO parameters such as ECC, DG, TARC, and CCL are analyzed. Therefore, the proposed asymmetric 3D antenna is suitable for off-device applications.

Isolation and Gain Improvement of a Rectangular Notch UWB-MIMO Antenna

This paper presents the performance improvement of a co-planar waveguide rectangularly notched UWB-MIMO antenna. The isolation and gain of the antenna are enhanced by using a parasitic isolator. The antenna consists of four microstrip patch antennas and an isolator. The UWB characteristic of the antenna is achieved by truncating the lower ends of the radiating patch by a semicircle. The rectangular notch characteristic is obtained by adding two electromagnetic bandgap structures on the backside of the antenna, which is attached to the radiator via shorting pin. The performance, especially the decoupling of the MIMO antenna is improved by using a novel parasitic decoupler, which is placed between the antennas to receive uncorrelated signals. The decoupling structure consists of a square shape metallic element with a circular slot inside and a half-semicircle slot edged at each corner. Four rectangular metallic stubs are extended from opposite parallel sides to improve further isolation. The simulated and measured results show that the antenna has a rectangular notch band (5.25–5.85 GHz) across the working band of 3–12.8 GHz. In addition, the antenna has a planar structure with an overall size of 60 × 60 × 1.52 mm3 and offers stable gain, reduced mutual coupling (<−21 dB), and lower envelop correlation (<0.001).

A goblet-shaped quad band-notched UWB antenna and its MIMO configurations

Abstract A goblet-shaped quad band-notched antenna is proposed as a prototype antenna. With three CSRR slots and two symmetrical C-like metal stubs, the antenna produced four notched bands to suppress 3.5 GHz WiMAX, 5.3 GHz lower band of WLAN, 5.8 GHz upper band of WLAN and 8.3 GHz X-band. To increase channel capacity and data rate, a two-port UWB-MIMO antenna-1 with quad notched-bands is introduced by placing two identical prototype antenna perpendicularly. The UWB-MIMO antenna-1 easily achieves high isolation of more than 25 dB, but it has big volume of 30 × 60 × 0.8 mm3. To keep miniaturization in size, a two-port UWB-MIMO antenna-2 is constructed by arranging two identical prototype antenna in parallel. With a slot in the common ground and an I-type metal parasitic stub, better than 15 dB port isolation is realized. The simulated and measured data indicate that the UWB-MIMO antenna-2 can reject the above four bands in working band of 3–11 GHz. Meanwhile, other characteristics of high port isolation, good radiation pattern and stable gain are observed. Having compact structure and favorable characteristics, the UWB-MIMO antenna-2 not only realized four notch bands, but also effectively improved the spectrum utilization, which is the highlight of the work.

Design of Dual-Band Notched UWB Antenna Loaded with Split Ring Resonators for Wide Band Rejection

ABSTRACT Nowadays, the design of a miniaturised ultra-wideband (UWB) antenna with wide dual band-notched characteristics gained widespread demand in wireless communications to reduce interference. The design of a planar CPW-fed circular UWB antenna loaded with split ring resonators and stubs is presented to eliminate two frequency bands. Two symmetrical circular split ring resonators are etched below the CPW feed at the backside of a circular UWB monopole antenna to suppress 3.61 GHz–5.57 GHz (sub-6 GHz band) wideband interference, whereas the 7.06 GHz–8.79 GHz (X-band uplinks and downlinks) band is suppressed by loading two L-shaped stubs. Slots are also made on the patch and ground to enhance impedance matching at a lower resonance frequency. The proposed notch band antenna has a compact size of 38 × 32 × 1.6 mm3 and has the highest gain of 5.75 dB at a frequency of 9 GHz. The parametric analysis has been performed to obtain optimised dimensions for better performance. The designed antenna is simulated, prototyped and tested to validate the antenna design.

Circular ring UWB antenna with reconfigurable notch band at WLAN/sub 6 GHz 5G mobile communication

Circular ring UWB antenna with reconfigurable notch band at WLAN/sub 6 GHz 5G mobile communication

Embedded Split Ring Resonator Tunable Notch Band Filter in Microstrip Transmission Lines

Novel design techniques for tunable and fixed frequency notch band filters are presented and validated with experiments. A notch band filter based on an Embedded Split Ring Resonator (ESRR) in a Microstrip Transmission Line (MTL) is presented. The physical dimensions of the ESRR determine the filter resonance frequency, which, when combined with a Varactor (Varactor Loaded ESRRs or VLESRRs), provides a continuously tunable resonance frequency. Tunable notch bands centered from 1.7 GHz to 4.8 GHz are obtained with resonators having an unprecedented electric length of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.05~\lambda _{0}$ </tex-math></inline-formula> at the lowest frequency, corresponding to a physical length of 7 mm and a total occupied area of 8.5 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . Two or more ESRRs are proposed to provide a deeper single notch band, a wider notch band, and/or multi notch bands. The proposed ESRRs are used jointly with a trapezoidal antenna to form 1) a notch band at 2.5 GHz; and, 2) dual notch bands at 2.5 GHz and 3.5 GHz. In addition, ESRRs are used in a Low Pass Filter (LPF) with cutoff frequency of 1 GHz to suppress undesired harmonic at 3.46 GHz and improve band rejection. The proposed MTL loaded by ESRRs, LPF and trapezoidal antenna are fabricated, measured and the results of simulations and measurements are in good agreement.

AMC Integrated Multilayer Wearable Antenna for Multiband WBAN Applications

In this paper, a compact, efficient and easy to fabricate wearable antenna integrated with Artificial Magnetic Conductor (AMC) is presented. Addition of slots and bevels/cuts in the rectangular monopole patch antenna yield a wide bandwidth along with band notches. The proposed antenna is backed with an AMC metasurface that changes the bidirectional radiation pattern to a unidirectional, thus, considerably reducing the Specific Absorption Ratio (SAR). The demonstrated antenna has a good coverage radiating away from the body and presents reduced radiation towards the body with a front-to-back ratio of 13 dB and maximum gain of 3.54 dB. The proposed design operates over a wide frequency band of 2.9 to 12 GHz (exceeding the designated 3.1−10.6 GHz Ultra-Wideband (UWB) band). The band notches were created using slots on the radiating patch in the sub-bands from 5.50 to 5.67 GHz and 7.16 to 7.74 GHz. The overall dimensions of the structure are 33 × 33 × 6.75 mm3. The antenna's radiation performance increased considerably with the addition of the AMC layer. The SAR values for the antenna are reduced by 85.3% when the AMC is used and are 0.083 W/kg which is well below the FCC SAR limits. The simple design, miniaturized profile, low SAR and wide operating bands with multiple band notches make the presented antenna an appealing choice for several UWB wearable body area network (WBAN) applications.

Novel Compact UWB Band Notch Antenna Design for Body-Centric Communications

In this paper, a novel and compact ultra-wideband (UWB) antenna with band-notched characteristics for body-centric communication is examined and implemented. The shape of the designed antenna looks like a ‘swan’ with a slotted patch. The performance parameters of this antenna for both the free space and on-body scenario for body-centric communication are analyzed and investigated through the simulation process using Computer Simulation Technology (CST). This antenna can avoid the interference caused by Wireless Local Area Network (WLAN) (5.15–5.825 GHz) and Worldwide Interoperability for Microwave Access (WiMAX) (5.25–5.85 GHz) systems with a band notch because of newly designed UWB antenna is revised small form factor sized. At first, the performance parameters like return loss response, gain, radiation patterns, and radiation efficiency on the free space of this UWB antenna are evaluated. After that, the on-body performance parameters of the antenna are also examined to place the antenna at various distances like 2 mm, 4 mm, 6 mm, 8 mm, and 10 mm away from 3-layers of phantom body model at frequencies of 3.5 GHz, 5.2 GHz, 5.8 GHz, 8 GHz, and 10 GHz. All the on-body performance parameter results are compared and analyzed with free space performance parameter results. Lastly, by changing patch slot length and ground plane length, parametric studies were done for performance comparison. Due to its compact size, novel shape and significant on-body performance, the proposed antenna is very suitable for multi-purpose healthcare applications and sports performance monitoring.

Miniaturized Novel UWB Band-Notch Textile Antenna for Body Area Networks

This paper presents the design and analysis of a miniaturized and novel wearable ultra-wideband (UWB) band-notch textile antenna for Body Area Networks (BANs). The major goal of building the antenna for wearable applications with band notch in X-band is to reject the downlink band (7.25 to 7.75 GHz) of satellite communication in the UWB frequency ranges of 3.1–10.6 GHz to keep away from interference. Computer Simulation Technology (CST) TM Microwave Studio, which is user-friendly and reliable, was used to model and simulate the antenna. The radiating element of the antenna is designed on Jeans’ textile substrate, which has a relative permittivity of 1.7. The thickness of the jeans’ fabric substrate has been considered to be 1 mm. Return loss, gain, bandwidth, impedance, radiation, and total efficiency, and radiation patterns are presented and investigated. The antenna is simulated placed on the three layers of the human body model, and the on-body results are summarized in comparison with free space. Results and analysis indicate that this antenna has good band-notch characteristics in the frequency range of 7.25 GHz to 7.75 GHz. The parametric study varying the relative permittivity of Jeans’ fabric substrate of this antenna is also evaluated. In addition, effects on the antenna parameters of variation of ground plane size have been reported. The antenna is 25 mm × 16 mm × 1.07 mm in total volume. Results reveal that this antenna achieves the design goal and performs well both in free space and on the body.

CPW-fed star shaped UWB antenna with and without band-notch characteristics

A CPW-fed star shaped slot like monopole antenna with and without ITU-8 band notch characteristics for ultra wideband communication are proposed. They comprise a stage 1 Koch fractal star shaped radiating patch, modified feedline and slot loaded CPW ground plane. The band notch characteristic is achieved by loading the radiating patch with half wavelength long meander line slot. An impedance bandwidth of 3.1-17.6 GHz with band rejection for 8-9 GHz band (ITU-8 band) (S11 ≤ -10 dB) is achieved. The band notch characteristic is modeled by an equivalent RLC resonant circuit. The equivalent circuit is validated with simulated input impedance and VSWR results. The proposed antenna provides an average gain of 4.4 dB over the entire band of operation for without band notched antenna. The radiation patterns are also observed to be omni-directional and bidirectional at lower frequencies with some distortions at higher frequencies. Non-band reject antenna configuration provides a fidelity factor of 90% along with a constant group delay over the entire operating band. The effect of various critical parameters on antenna performance is also analysed.

CPW-fed star shaped UWB antenna with and without band-notch characteristics

A CPW-fed star shaped slot like monopole antenna with and without ITU-8 band notch characteristics for ultra wideband communication are proposed. They comprise a stage 1 Koch fractal star shaped radiating patch, modified feedline and slot loaded CPW ground plane. The band notch characteristic is achieved by loading the radiating patch with half wavelength long meander line slot. An impedance bandwidth of 3.1-17.6 GHz with band rejection for 8-9 GHz band (ITU-8 band) (S11 ≤ -10 dB) is achieved. The band notch characteristic is modeled by an equivalent RLC resonant circuit. The equivalent circuit is validated with simulated input impedance and VSWR results. The proposed antenna provides an average gain of 4.4 dB over the entire band of operation for without band notched antenna. The radiation patterns are also observed to be omni-directional and bidirectional at lower frequencies with some distortions at higher frequencies. Non-band reject antenna configuration provides a fidelity factor of 90% along with a constant group delay over the entire operating band. The effect of various critical parameters on antenna performance is also analysed.

UWB MIMO HIGH DIVERSITY ANTENNA OF FOUR RADIATORS WITH SINGLE-BAND-REJECTION FOR WIRELESS APPLICATIONS

In this paper, Ultra-Wideband Multi-Input-Multi-Output (UWB-MIMO) antenna with band-notched features is introduced. The band notch of the antenna is designed by inserting T-strip into the radiating patch to eliminate the interference with WiMAX applications from 3 to 4 GHz. To improve the isolation and the diversity between the radiators, the antenna radiators are arranged orthogonally and decoupling structure is added between them. The proposed antenna has a compact size of 42 × 42 mm2 and its bandwidth extends from 2.5 GHz up to 12 GHz. This antenna has been manufactured and its characteristics have been measured. The results showed that the proposed UWB-MIMO antenna has a good performance with bandwidth from 2.5 GHz to 12 GHz, excluding the notched band for WiMAX applications. Furthermore, it has high isolation with a value higher than 18 dB and with a correlation coefficient lowers than 0.05 through the operated frequency bands. These properties made it good candidate for diversity

Compact Super Wideband Frequency Diversity Hexagonal Shaped Monopole Antenna With Switchable Rejection Band

To reduce interference from other wireless communications, a compact super wideband frequency diversity hexagonal shaped monopole antenna with switchable rejection band capabilities is proposed. The patch consists of hexagonal structure with an open-ended horizontal slot that divides the patch into upper and lower parts. The overall size of the proposed antenna is 36 mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times\,\,36$ </tex-math></inline-formula> mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times\,\,1.6$ </tex-math></inline-formula> mm on an FR-4 substrate material with a loss tangent of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$tan\delta$ </tex-math></inline-formula> = 0.02. The notch switchable features and the frequency diversity are controlled by changing the length of the resonator through alternating the state of two inserted parallel PIN diodes inside the horizontal open-ended slot. The upper part of the hexagonal patch is connected to the negative terminal of the diodes and the biasing circuit in the back layer through a conducting via. The lower part is connected to the positive terminal of the diode. When both diodes are OFF, the proposed antenna behaves as a super wideband covering a bandwidth from 3.37 GHz to 27.71 GHz. When both diodes are ON, there is a band notch and a frequency a frequency band (3.81 – 6.62 GHz) is filtered. The antenna’s radiation pattern is broadsided directional, and the efficiency is observed 92.9% and 96% for the ON and OFF cases, respectively. The reflection coefficient ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$S_{11}$ </tex-math></inline-formula> ) at the rejection band is −3.06 dB at 5.38 GHz. Hence, the proposed super wideband antenna is well-suited for applications in wireless communications.

Improved Multifunctional MIMO Cognitive Radio System for Integrated Interweave-Underlay Operations

This article presents the design of an integrated system involving multiple-input–multiple-output (MIMO) and cognitive radio (CR) technologies for sub-6 GHz applications. Two types of CR techniques, i.e., interweave and underlay CR, have been discussed in this article. The design model has a four-port multifunctional MIMO antenna system involving lumped elements for three selectable operation choices. Based on the switching conditions, the MIMO antenna system can operate as a wideband antenna (for sensing purpose), or narrowband frequency tunable antenna (for communicating purpose in interweave CR), or a wideband antenna with frequency tunable band notch (for communicating purpose in underlay CR). The sensing frequency range is 2.45–5.3 GHz. The interweave CR communicating antenna frequency tuning range is 3.6–4.2 GHz. To cover the entire desired spectrum range, i.e., from 2.5 to 4.2 GHz, another four-port narrowband MIMO antenna system with resonance frequency tuning from 2.5–3.6 is designed on the other/backside of the substrate. In the underlay CR communicating antenna, the stopband frequency tuning range is 3.1–3.85 GHz. The complete structure is having dimensions of 110 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times $ </tex-math></inline-formula> 70 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times $ </tex-math></inline-formula> 1.52 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> . The measurements are performed, and good matching is found between simulated and measured results.

Sprocket gear wheel shaped printed monopole ultra‐wideband antenna with band notch characteristics: Design and measurement

A compact ultra-wideband (UWB) printed monopole UWB with dual band-notched characteristics has been designed and investigated in this manuscript. The Wi-MAX and wireless local area network (WLAN) band rejection characteristics have been obtained by employing the circular ring and arc-shaped slot along with rectangular slot in radiating patch. Overall size of proposed UWB antenna is 27 × 27 × 1.6 mm3, which consists of sprocket gear wheel shaped structure as a core radiating patch element and excited by using 50 Ω coplanar waveguide feed. The proposed antenna exhibits the UWB frequency spectrum from 3.1 to 10.6 GHz along with Bluetooth frequency range 2.4–2.48 GHz without disturbing overall dimensions of antenna. Proposed antenna reveals the measured VSWR operating bandwidth of 10.0 GHz in the frequency range from 2.0 to 12.0 GHz along with Wi-MAX and WLAN rejected bands. Moreover, proposed antenna adorns the measured gain of −8.28 and − 9.98 dBi at rejected frequency bands, whereas, at other frequencies, it changes between 1.5 and 5.0 dBi. The radiation efficiency of proposed UWB antenna varies from 84% to 97% except rejected frequency bands. Group delay and radiation pattern have also been analyzed and found appropriate for the current UWB applications. Finally, the optimized structure of antenna with dual band rejection characteristics has been fabricated and tested for the authentication of simulated results. Both the results are compared and are found in good agreement with each other.

Design and circuit analysis of a single and dual band-notched UWB antenna using vertical stubs embedded in feedline

Within the frequency band designated by the FCC for UWB systems, there are other frequency bands that are also designated for use for other technologies like WLAN (5.15 – 5.35 GHz) and WiMAX (3.3–3.7 GHz). These systems can cause interference with UWB systems when operated at the same time. Therefore, an antenna operating in the UWB spectrum needs to have band-notch capabilities in order to mitigate interference resulting from nearby communication systems operating within the UWB frequency band. In this paper, the notched bands are achieved by using vertical stubs protruded from a microstrip feedline. The antenna is etched on a 25 × 30 mm2 substrate. Two antenna structures are presented; one is designed to notch an intended narrowband from 3.3 – 3.6 GHz and the second is designed to include an additional band notch from 5.15 – 6 GHz. The simulations and measurements show that the proposed antennas achieve an ultra-wide bandwidth of 3–10.6 GHz with successful single and dual band-notches, good gain and good group delay rejection in the notch bands. Stable radiation patterns with low cross polarization are also realized across the operating bandwidth. A detailed analysis of how the filtering is also achieved using circuit theory is presented in this work as well.

Small size monopole antenna with tri-band notch characteristics for broadband application

Abstract In this research article, the design of a broadband monopole antenna with triband notch characteristics is proposed. Notch characteristics are achieved by using an E-shaped slot on the patch and a U-shaped slot on the 50 Ω microstrip feed line. An E-shaped slot is introduced on the metal patch to reject one frequency band of 6.6 − 7.5 GHz and when an additional U-shaped slot is introduced on the microstrip feed line, it provides two-notch frequency bands of 4.8 − 5.7 GHz and 14.2 − 17.5 GHz. The notch bands are effectively used to avoid undesired interference from the WLAN, C band, and Ku band. The proposed antenna provides a very broad frequency range from 3.3 − 19.5 GHz except for three notch bands. The antenna is small in size and easy to design with only a volume of 29 mm × 21mm × 1.6 mm. The antenna is useful for broadband applications.

Infinite length slotted ultra-wideband monopole antenna using step-feed with band notch characteristics

AbstractIn this work, a printed ultra-wideband (UWB) antenna has been proposed exhibiting band notch characteristics. The proposed design covers the entire UWB band except for the 3.5 GHz band providing the band notch for the WiMAX band. This design consists of two-quarter elliptical patches placed symmetrically over the FR4 substrate. The elliptical shape of the patch is responsible for the UWB band achieved. The slot has been created on the optimized patch area to achieve the desired characteristics providing a notch for the WiMAX band. The slot in the patch is so perfectly designed that it gives the patch a perfect shape of butterfly wings. After designing, the proposed antenna was simulated and then fabricated. The fabricated and simulated results are in close agreement with each other which shows, the proposed UWB antenna is good enough for biomedical applications.