Notched Ultra-wideband Antenna Research Articles

A quad port dual band notch UWB MIMO antenna using hybrid decoupling structure

A four-port dual-band notch ultrawideband (UWB) multiple input and multiple output (MIMO) antenna for automotive applications is presented. Initially, a circular patch monopole antenna is designed and optimized by embedding a rectangular stub onto the radiator and lowering the ground plane to realize the UWB frequency spectrum. The dual-band frequency notch, from 4.6 to 5.9 and 6.8–8.8 GHz, is achieved using a half wavelength slot onto the feedline and a pair of H-shaped stubs across the feedline, respectively, to cover WLAN and complete x-band satellite communication. Further, the designed dual-band notch UWB antenna is transformed to a four-port MIMO antenna with interelement spacing much smaller than λ/4 (λ at 3.1 GHz) and a size of 0.46 × 0.41 × 0.01 λ3. Isolation improvement is achieved by a hybrid decoupling technique comprising a distinctive neutralization line (NL) and defected ground structure (DGS). The average isolation of the proposed design is better than 22 dB. Characteristic mode analysis of the proposed antenna is performed to analyze the specific significant mode and their contribution to the antenna radiation. The antenna design's diversity and time-domain properties are analyzed and found suitable for automotive applications. The antenna's electromagnetic interaction with the electrically large structure is studied by mounting the antenna onto an open-source automobile model, and the gain is determined to be more than 6.1 dB at the antenna's resonant frequencies.

Compact UWB Monopole Antenna with Tunable Dual Band Notched Characteristics for WiMAX and WLAN Applications

The present work shows a planar compact ultra-wideband (UWB) monopole antenna with controllable dualband-notch frequencies at 3.3 GHz for WiMAX and 5 GHz for WLAN. In the proposed antenna, the lower notchband (at a frequency of 3.3 GHz) is made by cutting a thin horizontal strip on top of the radiating patch. The uppernotch band (at a frequency of 5 GHz) is made by putting two narrow parasitic strips in the shape of an “I” oneither side of the radiating patch. The incorporation of three varactor diodes between the radiating patch and three metallic strips provides the flexibility of adjusting the notch frequencies. The notch band tunability between 3.15 GHz and 3.69 GHz and between 4.93 GHz and 5.59 GHz, respectively, is achieved by changing the bias voltageof the varactor diode between 0 V and 30 V. The gain and efficiency characteristics of the designed antenna alsoexhibit band rejection at the respective notch frequencies. The design principle is validated by fabricating andmeasuring a prototype of the proposed dual-band, notched UWB antenna. For three different bias voltages of thevaractor, the simulated and experimental findings are in reasonable agreement. The proposed works demonstratebetter-notch characteristics as compared with other reported works over the UWB range

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.

A Quadruple Notch UWB Antenna with Decagonal Radiator and Sierpinski Square Fractal Slots

A novel quadruple-notch UWB (ultrawideband) antenna for wireless applications is presented. The antenna consists of a decagonal-shaped radiating part with Sierpinski square fractal slots up to iteration 3. The ground part is truncated and loaded with stubs and slots. Each individual stub at the ground plane creates/controls a particular notch band. Initially, a UWB antenna is designed with the help of truncation at the ground plane. Miniaturization in this design is achieved with the help of Sierpinski square fractal slots. Additionally, these slots help improve the UWB impedance bandwidth. This design is then extended to achieve a quadruple notch by loading the ground with various rectangular-shaped stubs. The final antenna shows the UWB range from 4.21 to 13.92 GHz and notch frequencies at 5.02 GHz (C-band), 7.8 GHz (satellite band), 9.03, and 10.86 GHz (X-band). The simulated and measured results are nearly identical, which shows the efficacy of the proposed design.

A compact highly isolated two‐ and four‐port ultrawideband Multiple Input and Multiple Output antenna with Wireless LAN and X‐band notch characteristics based on Defected Ground Structure

SummaryA novel two‐ and four‐port antenna structure are proposed to achieve improved isolation and operate in the ultrawideband (UWB) frequency range. The projected designs comprise a hybrid circular and rectangular embedded UWB antenna with a partial ground plane. The alteration of the radiating and ground planes modifies the current flow and aids in realizing a broader bandwidth. The dual‐band notches are created on UWB using slot and stubs. The U‐shape slot on the feedline neutralizes the current flow at 5.2 GHz, and a pair of symmetrical H‐shape stubs across the feedline couples the current flow from the feedline to stubs at 7.4 GHz frequency, and negligible current reaches the radiator. The dual‐band notch UWB antenna is reproduced to create two‐port and four‐port MIMO antennas with a less than quarter wavelength spacing. Using a deficient ground structure, better isolation between the interelements is achieved. The projected two‐ and four‐port design has overall physical geometry of 0.2λ × 0.4λ × 0.02λ and 0.5λ × 0.4λ × 0.02λ and provides a measured impedance bandwidth between 3.3–12.8 and 3.1–12 GHz, respectively. The distinctive feature of both antenna designs is incorporating simple and effective defective ground structures as decoupling structures in the ground plane to generate better than 25 dB isolation across the operational spectrum. The current between the interelement is suppressed via the ground plane, leading to mutual coupling reduction. In addition, complete MIMO diversity parameters and time‐domain characteristics are explored, and the findings show that the proposed designs are appropriate for wireless applications.

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 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.

A Compact Dual-Band Notched UWB Antenna for Wireless Applications

This article presents the design and analysis of a V-shaped ultrawideband (UWB) antenna and dual-band UWB notch antenna. A rectangular slot is cut into a semicircular partial ground plane of the antenna to achieve ultrawide bandwidth. A U-shape slot is etched on a V-shaped patch that radiates, and an inverted U-shape parasitic resonator is placed beside the feedline to generate dual-band notch characteristics. The overall dimension of the proposed antenna is . The proposed UWB antenna has a gain of 9.8 dB, S11 < −10 dB, impedance bandwidth in the range of 3.4 to 12.3 GHz, response with a linear phase, group delay <1 ns, and stable radiation pattern. The UWB notch antenna shows strong rejection in the WLAN band from 5.15 to 5.8 GHz with a notch at 5.6 GHz and X band from 9.1 to 10.5 GHz with a sharp notch at 9.6 GHz, having a S11 < −10 dB impedance bandwidth ranging from 3.2 to 11.7 GHz. This antenna also exhibits a stable radiation pattern, group delay <1 ns, and linear phase response throughout the bandwidth except at the rejection frequencies.

Design a new notched UWB antenna to rejected unwonted band for wireless communication

This paper presents a slotted design for ultra-wideband (UWB) antenna. Design of a rectangular UWB antenna covering the frequency range 3.1-10.6 GHz, to achieve notch characteristics in the bands at 3.1-8.4 GHz and 8.6-10.6 GHz. By changing the direction of distribution of current to apply this technique by inserting three C-shaped holes and two pairs of rectangular notches below the antenna. The simulation results reveal that the proposed structure is in good accord with the simulation results. The proposed UWB antenna size is (100x90x1.6 mm) 3 . This proposed design could provide a solution to eliminating bands that interfere in a UWB band depending on the aperture design. The simulated findings reveal that the UWB antenna operates in the 8.5 GHz center frequency range and rejects all frequency bands utilizing slits. This antenna design can provide a solution to remove UWB bands from 3.1-10.6 except for 8.5 GHz which only works. By using the notch, we got a large increase in the gain. makes to be a suitable candidate for X-band-UWB applications.

Design and research of a miniaturized four notch UWB antenna

In order to effectively suppress the interference of narrow-band communication systems such as WiMAX band, international satellite band, X band and the ITU band, this paper designs a miniature ultra wideband (UWB) antenna. The improved rectangle is used as the radiation patch. The semicircular groove is dug in the upper part of the rectangle and the two corners below are cut off. The long triangle is also cut on both sides of the end of the microstrip line. The fish bone groove is well modified in the middle of the rectangular ground plate to obtain the perfect ultra wideband characteristics. By digging a semi-circular groove on the radiation patch to introduce T-shaped branches, and opening an inverted U-shaped groove in the center of the radiation patch, introducing symmetrical C-shaped open branches on both sides of the feeder line and etching U-shaped narrow gaps on the feeder line, four band notch characteristics of 3.24−3.8 GHz, 4.5−4.97 GHz, 7.24−7.76 GHz and 8.0−8.54 GHz are produced, which better suppresses the interference in the notch band, shows that the antenna can work normally in the frequency band of 3.0−13.09 GHz, and the four notch baud property of the antenna also expands the application field, which is suitable for many ultra wideband communication systems.

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.

Triple Rectangular Notch UWB Antenna Using EBG and SRR

This paper investigates an ultra-wideband (UWB) antenna with a triple-rectangular notch band at 5G, WLAN, and Satellite downlink bands. The 5G and WLAN bands are notched by using a pair of electromagnetic bandgap (EBG) structures while the satellite downlink band is notched by using two split-ring resonators (SRRs). The EBG structure is a metallic conductor loaded on the backside of the radiator which is connected to the patch via a shorting pin. The SRRs consist of a pair of metallic rings etched on the backside of the feedline. The simulated and measured results show that the proposed antenna has an operational bandwidth from 3.1 - 11.8 GHz for |S11| <; -10 rejecting 5G sub-6 GHz (3.4 - 3.9 GHz), WLAN (5.15 - 5.825 GHz), and satellite downlink band (7.25 - 7.75 GHz) signals with high selectivity. The peak gain of the UWB antenna is 3.86 dBi but it sharply decreases up to -13 dBi at stop-bands. The antenna also has additional advantages of the overall compact size (20 x 26 x 1.52 mm3) with stable gain and radiation patterns at the pass-bands.

Design of a Planar Tri-Band Notch UWB Antenna for X-Band, WLAN, and WiMAX

In this work, a new ultra-wideband (UWB) antenna design with 2.08GHz to 12GHz impedance bandwidth and triple-band specifications is presented. The proposed antenna is formed by a truncated square patch, a partial ground plane, and a 50Ω microstrip line. Three different types of slots were used in order to induce notched bands. A C-shaped slot is etched on the radiating patch to obtain a notched band in 3.31-4.21GHz for WiMAX. An inverted U-shaped slot in the micro-strip line induces a second notched band in order to reduce the interference with the WLAN [5.04-6.81GHz]. Finally, two inverted L-shaped slots around the micro-ribbon line on the ground plane allow the X-band [9.13 to 10.75GHz]. The antenna has dimensions of 32×28×1.6mm3. The Ansoft software (HFSS) was used to simulate the proposed structure. The simulation results are in good agreement with the measurement results. The antenna shows an omnidirectional radiation pattern.

Stub loaded UWB Antenna for Dual Notch Bands

A Dual Notch ultra wideband antenna (UWB) is presented in this communication. The dual notch bands covers the WLAN and WiMAX frequencies. The Ultra wideband is achieved by introducing multiple techniques into a basic antenna. The basic radiating element is a rectangular patch with a pentagonal slot at the center for which the bottom two edges of the patch are truncated in steps. A ground with a rectangular slot at the middle is considered. The cumulative effect of edge truncated slotted patch and partial defective ground plane will generate ultra wideband. To generate notch bands two stubs are loaded into the pentagonal slot there by enabling isolation in the WLAN and WiMAX frequencies. Proposed antenna is having a bandwidth of 10.37GHz ranging from 3.08GHz to 13.45GHz with isolation ranging from 3.66GHz to 3.86GHz and 4.9GHz to 5.6GHz.

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.

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.

Design and analysis of triple notch ultrawideband antenna using single slotted electromagnetic bandgap inspired structure

ABSTRACTA microstrip line fed pentagonal printed ultra wideband (UWB) monopole antenna with partial ground plane having triple notches is proposed. The realized antenna has an operating bandwidth (VSWR ≤ 2) ranging from 3.1 GHz and continuing beyond 12 GHz. A novel mushroom-shaped slotted electromagnetic bandgap (EBG) inspired structure is used near the feedline to introduce triple notches at CBRS (3.5–3.7) GHz, WLAN (5.15–5.725) GHz and X-band downlink satellite communication (7.25–7.75) GHz frequencies. The band notch characteristics are demonstrated with current distribution and impedance analysis. Further, the proposed structure has stable radiation patterns, gain and group delay in the UWB range except the notch frequencies. Finally, a prototype of the proposed antenna is fabricated and measured results are in good agreement with the simulated results.

Study on frequency and impulse response of novel triple band notched UWB antenna in indoor environments

In this paper, a novel fork shaped structure backed plane is added to a simple UWB (ultra wideband) slot antenna to enhance the impedance bandwidth as well as create triple band notched characteristics for Impulse Radio (IR) UWB applications. This fork-shaped structure is connected to a rectangular radiating patch at four different points through the cylindrical pins. The proposed antenna with this fork-shaped structure shows a very wide impedance bandwidth which spans from 2.5 up to more than 20 GHz and offers triple band-notched properties in WiMAX, WLAN and X-band downlink satellite communication spectrums. Moreover, the proposed antenna shows good radiation features such as gain, radiation efficiency and radiation patterns. A comprehensive investigation on the antenna time domain performance is also performed throughout the paper, and the effect of the proposed antenna on the two popular excitation pulses including modulated Gaussian (MG) and square root raised cosine (SRRC) pulses is fully investigated. A frequency-domain measurement setup is applied to measure time domain characteristics of the proposed antenna. Also, the realistic indoor multipath propagation channel characteristics when the proposed antennas are applied as the transmitter and receiver antennas are studied. Sub-band divided ray tracing method is used to simulate channel characteristics.

Study on frequency and time domain properties of novel triple band notched UWB antenna in indoor propagation channel

Frequency and time domain characteristics of a novel and compact triple band notched ultra wideband (UWB) monopole antenna are investigated. To realize UWB characteristics, the lower edges of a simple rectangular radiating patch are truncated and a new structure including a semi-circle like ring stub is added to the rear side of the antenna. To avoid interferences with coexisting narrow band systems such as WiMAX, WLAN, and X band, two inverse L-shaped slots, a semi-circle like ring slot and two C-shaped resonators are incorporated in the antenna geometry, respectively. The effect of the proposed antenna on a modulated Gaussian pulse as an excitation signal in different scenarios is fully studied. Moreover, the channel impulse response of a simple indoor environment is investigated when a pair of the proposed antennas are applied as transmitting and receiving antennas. Sub-band divided ray tracing method based on the geometrical optics and uniform theory of diffraction is used to simulate the impulse response of the propagation channel. A frequency domain measurement campaign is also employed to measure the channel characteristics. The measured results are compared with those obtained from the simulations to validate the design procedure.