Band Notch Research Articles

Compact circular patch UWB antenna with WLAN band notch characteristics

ABSTRACTThe present study demonstrates the designing and characterization of a circular patch antenna having an impedance bandwidth of 2.4–13.8 GHz with band notch at WLAN operating region. The small size (30 × 40 mm2) and large bandwidth (140.7% fractional band width) makes it suitable for different UWB applications. Different size reduction and matching techniques are used in this model to achieve a better response. The Quarter wave transformer matching technique is used for broad band impedance matching between the radiating circular patch and the 50 ohm source impedance. The simple design and good agreement between the simulation and the experimental results makes the design a suitable candidate for practical applications. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1068–1073, 2016

Ultra-Wideband Planar Monopole Antenna with WiMAX and WLAN Band Rejection Characteristics

Investigations on the performance of dual band notched printed monopole ultra- wideband (UWB) antenna are proposed. The proposed configuration consists of a beveled ground plane with two U-slots embedded on the radiation element for realizing the dual band notch characteristics. The designed antenna can provide an impedance bandwidth from 3.1 to 11 GHz for a VSWR < 2 with two notched bands at 3.38 –3.78 GHz for WiMAX and 4.9 – 5.83GHz for WLAN. The measured VSWR band notch, radiation patterns, gains and group delay characteristics are presented.

Modified octahedron shaped antenna with parasitic loading plane having dual band notch characteristics for UWB applications

The design of a compact modified octahedron shaped dual band notched ultra wide-band antenna is presented in this article. The impedance bandwidth of the designed antenna has been enhanced by modifying the shape of the radiator by introducing fractal geometry and a modified ground plane. The proposed antenna offered an impedance bandwidth of 2.4 GHz–19.5 GHz (156% Fractional bandwidth). Two rectangular split ring resonator structures are introduced in the radiator to achieve two notched bands which ranges from 3.3 GHz to 3.7 GHz (WiMAX) and 5.15 GHz–5.85 GHz (WLAN) band. The antenna gain varies from 1 to 4 dBi over the operating band except the notched bands. The overall dimension of the designed antenna has a compact size of 33 × 40 mm2. The experimental and simulation results are in good agreement. The proposed antenna has wider bandwidth and smaller dimension over the already reported in the literature. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:426–434, 2016.

Quadruple Band-Notched Trapezoid UWB Antenna with Reduced Gains in Notch Bands

A compact ultra-wide band antenna with a quadruple band-notched characteristic is proposed. The proposed antenna consists of a slotted trapezoid patch radiator, an inverted U-shaped band stop filter, a pair of C-shaped band stop filters, and a rectangular ground plane. To realize the quadruple notch-band characteristic, a U-shaped slot, a complementary split ring resonator, an inverted U-shaped band stop filter, and two C-shaped band stop filters are utilized in this antenna. The antenna satisfies the –10 dB reflection coefficient bandwidth requirement in the frequency band of 2.88–12.67 GHz, with a band-rejection characteristic in the WiMAX (3.43–3.85 GHz), WLAN (5.26–6.01 GHz), X-band satellite communication (7.05–7.68 GHz), and ITU 8 GHz (8.08–8.87 GHz) signal bands. In addition, the proposed antenna has a compact volume of 30 mm× 33.5 mm× 0.8 mm while maintaining omnidirectional patterns in the H-plane. The experimental and simulated results of the proposed antenna are shown to be in good agreement.

A compact planar self-affine sierpinski carpet fractal monopole antenna with band notch characteristics for ultra wideband communications

This paper presents a novel compact planar self-affine sierpinski carpet fractal monopole coplanar waveguide (CPW) fed ultra-wideband (UWB) antenna with improved gain, radiation efficiency and a sharp band-notched characteristics for the rejection of interfering WLAN (5.15---5.825 GHz) assigned for IEEE 802.11a narrow band communication system. The significant improvements in gain and radiation efficiency are achieved by the introduction of carpet fractals in the radiating circular patch. The antenna covers the entire UWB frequency band (3.1---10.6 GHz) with voltage standing wave ratio (VSWR) ≤ 2 which depicts optimum impedance matching of the proposed antenna structure. The antenna occupies a compact size of 36 × 41 mm2 and band rejection is achieved by embedding compact C--shaped slots with folded arms on the ground planes of the CPW feed lines which yield a very sharp notch for WLAN band. The band rejection is demonstrated by a high value of VSWR around notch frequency. Compact self-affine sierpinski carpet fractals are introduced in the radiating circular patch to improve performance of the UWB antenna. The proposed fractal antenna exhibits improved gain that varies from 2 to 6 dBi and optimum radiation efficiency which varies from 85 to 99.9 % over the UWB frequency range. The gain and radiation efficiency are suppressed with strong dips at the desired rejection WLAN band. Omnidirectional radiation characteristic is achieved over UWB frequency range which supports the uniform transmission of signal irrespective of the orientation of the antenna direction.

A compact fractal UWB antenna with reconfigurable band notch functions

ABSTRACTIn this paper, a compact reconfigurable single/dual notch band ultrawideband (UWB) antenna with triple notch band characteristics is presented for portable UWB applications. The desired compactness and wideband is achieved using fractals in antenna design. It has the compact dimensions of 24.5 mm × 20 mm. The single/dual notch band reconfigurability is demonstrated in WiMAX band as well as in X‐band using two p‐i‐n diodes for efficient utilization of UWB bands in case of no interference scenarios. The band rejections are obtained by introducing two C‐shaped slots in the fractal monopole, whereas band rejection in WLAN band is achieved by placing two C‐shaped single split ring resonator on either sides of feed line. In addition, the time‐domain characteristic of antenna is also evaluated in terms of fidelity factor, which is more than 0.71. These results illustrates that the presented antenna is appropriate candidate for portable UWB applications. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:509–514, 2016

Compact integrated bluetooth UWB bandnotch antenna for personal wireless communication

ABSTRACTIn this paper, a compact microstrip fed octagonal ring dual band antenna for integrated Bluetooth (2.4∼2.484 GHz) and ultra‐wideband (UWB; 3.1∼10.6 GHz) applications withband notch characteristics for wireless local area network (WLAN; 5.15∼5.825 GHz) is proposed and investigated. The entire UWB frequency band is achieved by using an octagonal ring patch and a modified ground plane. The dual band operation is achieved by integrating Bluetooth characteristicsby embedding a quarter wavelength resonating strip at the center of the octagonal ring radiating patch. Further, to avoid the potential interferences of the UWB system with the existing narrow band system such as WLAN in the proposed antenna,an inverted U‐shaped slot in the feed line has been etched to obtain the desired band notch characteristics. The proposed antenna is designed, fabricated on a FR4 glass epoxy substrate and tested. The proposed antenna yields a measured impedance bandwidth over the frequency range of 2.40 ∼ 2.5 GHz and 3.1 ∼ 13 GHz to exhibit the integrated Bluetooth and UWB characteristics respectively for VSWR &lt; 2 with an excellent rejection band of 5.15 ∼ 5.90 GHz to prevent interferences of WLAN signals. The proposed antenna exhibits directional and omnidirectional radiation pattern in E and H‐plane with stable gain and good time domain characteristics at all desired frequency bands. The compact dimension of 38 × 30 mm2 of the proposed antenna makes it a suitable candidate for personal wireless communication application. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:540–546, 2016

Mini UWB-Bluetooth Antenna Design with Band-Notched Characteristics

Objective: In this paper a novel small size antenna for Ultra Wide Band (UWB) and Bluetooth application is proposed which there by minimize the potential interference between the UWB system and WLAN system. Band notch are designed to reject 5.15-5.5825 GHz frequency band f Wireless Local Area Network (WLAN) application based on IEEE 802.11 standard. Methods/Statistical Analysis: This is achieved by choosing a small monopole antenna with U shaped radiator and a rectangular ground plane. A pair of L shaped slot is etched on the ground to obtain the WLAN band notched characteristics. Findings: The antenna consisting of fork shaped radiating element is fed to a 50 ohm micro strip line. Dimension of the central arm govern the Bluetooth band while the U shaped monopole antenna govern the Ultra Wide Band UWB. Furthermore by placing two L shaped slot on the ground plane. Adjusting the total length of the L shaped slots on the ground plane the desired band notched frequency can be controlled to minimize the potential interference in the system. The characteristics of the designed structure are achieved using finite element method based electromagnetic simulator, HFSS and the fabrication is done using FR4 substrate. Applications/Improvements: The dimensions are varied to get the desired radiation promising return loss data with good matching, high gain, good efficiency and reject bands. The experimental result shows that the proposed antenna is a good candidate for application in UWB communication systems.

Band-Notched UWB Antenna with Switchable and Tunable Performance

A band-notched UWB antenna is presented, which can switch between two notch bands and tune the central frequency simultaneously. It is the first time that the switchable and tunable behaviours are combined together in band-notched UWB antennas. In the band-notched structure, PIN diodes are used to switch the lower and upper frequency bands, while varactors could vary the central frequency of each notch band continuously. Measurement results show that the notch bands could switch between 4.2 GHz and 5.8 GHz when the state of varactors is fixed, and the ranges of tuning are 4.2–4.8 GHz and 5.8–6.5 GHz when the state of PIN diodes is ON and OFF, respectively.

A Minimized MIMO-UWB Antenna with High Isolation and Triple Band-Notched Functions

AbstractA compact high isolation MIMO-UWB antenna with triple frequency rejection bands is proposed for UWB communication applications. The proposed MIMO-UWB antenna consists of two identical UWB antennas and each antenna element has a semicircle ring shaped radiation patch fed by a bend microstrip feeding line for covering the UWB band, which operates from 2.85 GHz to 11.79 GHz with an impedance bandwidth of 122.1 %. By etching a L-shaped slot on the ground plane, and embedding an “anchor” shaped stub into the patch and integrating an open ring under the semicircle shaped radiation patch, three notch bands are realized to suppress WiMAX (3.3–3.6 GHz), WLAN(5.725–5.825 GHz) and uplink of X-band satellite (7.9–8.4 GHz) signals. The high isolation with S21&lt;–20 dB in most UWB band is obtained by adding a protruded decoupling structure. The design procedure of the MIMO-UWB antenna is given in detail. The proposed MIMO-UWB antenna is simulated, fabricated and measured. Experimental results demonstrate that the proposed MIMO-UWB antenna has a stable gain, good impedance match, high isolation, low envelope correlation coefficient and good radiation pattern at the UWB operating band and it can provide three designated notch bands.

A Very Compact and Low Profile UWB Planar Antenna with WLAN Band Rejection.

A low-cost coplanar waveguide fed compact ultrawideband (UWB) antenna with band rejection characteristics for wireless local area network (WLAN) is proposed. The notch band characteristic is achieved by etching half wavelength C-shaped annular ring slot in the radiating patch. By properly choosing the radius and position of the slot, the notch band can be adjusted and controlled. With an overall size of 18.7 mm × 17.6 mm, the antenna turns out to be one of the smallest UWB antennas with band-notched characteristics. It has a wide fractional bandwidth of 130% (2.9–13.7 GHz) with VSWR < 2 and rejecting IEEE 802.11a and HIPERLAN/2 frequency band of 5.1–5.9 GHz. Stable omnidirectional radiation patterns in the H plane with an average gain of 4.4 dBi are obtained. The band-notch mechanism of the proposed antenna is examined by HFSS simulator. A good agreement is found between measured and simulated results indicating that the proposed antenna is well suited for integration into portable devices for UWB applications.

A U-Shaped Slot UWB Antenna with Flexible and Wide Tunable Dual Notch Band

A coplanar waveguide (CPW) fed ultra-wideband (UWB) antenna with flexible and wide tunable dual bandnotched characteristics is proposed in this paper. The dual band-notched function is achieved by using an U-shaped slot inserted into the ellipse radiation patch and by using an elliptic parasitic slit placed near the ground plane. The wide tunable band-notched characteristic is implemented by adjusting the length of U-shaped slot and by adjusting the length of ellipse parasitic slit. The design aims to achieve wide reconfigurable band-notched features on the UWB antenna. The simulated results indicate that the proposed antenna has a wide bandwidth (VSWR under 2) from 2.9GHz to 12.6GHz with fractional bandwidth of 125%, and has a wide tunable notch band center frequency from 4.5GHz to 12.4GHz.

Compact planar UWB monopole antenna with dual band-notch characteristics

In this article, a compact Mickey shaped monopole UWB antenna is presented with dual notch band characteristics. The proposed antenna VSWR (<2) and return loss (<-10 dB) results have been verified by EM simulator and the measured impedance bandwidth covers from 2.88 GHz to 12.11 GHz which confirms the bandwidth. Furthermore, the two notched bands, i.e., WiMAX (3.3-3.7 GHz) along with C band (3.7-4.2 GHz) and WLAN (5.15-5.825 GHz) are band rejected so that the interference is mitigated in the existing wireless system. The proposed antenna is fabricated with compact dimensions of 20 × 20 mm² = 400 mm² on FR4 substrate with permitivity 4.4 and thickness of 1.6 mm. The measured gain and radiation characteristics of proposed antenna provide best results showing omni-directional pattern in H-plane and dipole like pattern in E-plane.

Design and Analysis of Ultra-wideband Micro Strip Patch Antenna with Notch Band Characteristics

A new design of ultra-wideband (UWB) micro strip patch antenna with notch band characteristic for wireless local area network (WLAN) application is presented in this paper. The proposed antenna consists of a rectangular patch with a partial ground plane that is fed by 50 Ω micro strip line. A notch band function is created by inserting overlapped one U-shape and one C-shape slot on the radiator patch, added additional patch to the ground plane side and slit in truncated ground plane. The proposed antenna potentially minimized frequency interference between WLAN and UWB system. This antenna with the size of 26 mm × 32 mm (W×L) and the simulated results show that the antenna can operate over the frequency band between 3.1 and 10.45 GHz for voltage standing wave ratio (VSWR) > 2 with band notch 5.06-5.825 GHz. Besides in the working band, the antenna shows good radiation pattern in the H-plane and the E-plane and has good time domain characteristic.

COMPACT WLAN BAND-NOTCHED PRINTED ULTRAWIDEBAND MIMO ANTENNA WITH POLARIZATION DIVERSITY

A novel uniplanar compact WLAN band-notched printed ultra wideband (UWB) multiple-input multiple-output (MIMO) antenna with dual polarization for high data-rate wireless communication is proposed. The antenna consists of two CPW-fed floral radiating elements along with a decoupling structure to ensure high isolation. The band notch at the WLAN frequency band is achieved by etching one single U-shaped slot on each antenna element. Results show that the proposed antenna gives impedance bandwidth from 2.7 GHz to 10.9 GHz with notched frequency band from 5.1 GHz to 5.9 GHz. The proposed antenna provides nearly omnidirectional radiation pattern, low envelope correction coefficient (ECC), moderate gain, efficiency, fidelity factor and pattern stability factor (PSF). Furthermore, diversity characteristics such as mean effective gain (MEG) and diversity gain (DG) are also studied. Moreover, the time-domain analysis displays minimum dispersion to the radiated pulse. All these features make the proposed antenna a good candidate for future high data-rate wireless communication systems with polarization-diversity operation, where the challenge of multipath fading is a major concern.

TUNABLE BAND-NOTCHED CPW-FED UWB MONOPOLE ANTENNA USING CAPACITIVELY LOADED MICROSTRIP RESONATOR FOR COGNITIVE RADIO APPLICATIONS

In this paper, a new compact coplanar waveguide (CPW) ultrawideband (UWB) antenna with an electronically tunable notched band is proposed for an overlay onto cognitive radio (CR) systems. The proposed antenna utilized a rectangular microstrip resonator in the bottom layer to create a single notched band and to realize tunability and miniaturization using varactors. The center frequency of the notched band can be electronically tuned by changing the effective electrical length of the microstrip resonator, which is achieved by employing two varactor diodes at the resonator edges. Moreover, the simple biasing of the varactor diodes has a small effect on the antenna performance. Experimental results show that the proposed antenna can selectively have a band notch over a continuous operating band about 1.44 GHz from 4.77 to 6.21 GHz to prevent the interference to the primary users that are operating in this band such as the WLAN (5.15-5.35 GHz; 5.725-5.825 GHz) and the WiMAX (5.25- 5.825 GHz). Good agreement is found between the simulated and the measured data.

DUAL NOTCH UWB FORK MONOPOLE ANTENNA WITH CRLH METAMATERIAL LOAD

A novel fork monopole antenna is presented using metamaterial structures. The prototype monopole antenna consists of split-ring-resonators (SRR) as an electric-LC resonator and small ground. To prove the concept, the prototype antenna is designed and fabricated for wireless communication systems. The monopole structure makes ultra wideband (UWB) impedance bandwidth condition for 2- 12 GHz. On the other hand, the prototype antenna shows dual notch band characteristics at 3.5-4.5 GHz and 5.3-6 GHz for WiMAX and WLAN rejection. The prototype antenna radiates omnidirectionally and has a gain altered between −4.5 and 6.2 dBi in 2.5-12 GHz, with an average gain of 4.2 dBi. The metamaterial model is suggested for the CRLH (ELC) resonator, and in addition, the parametric study for CRLH (ELC) resonator is presented for clarification of its manner on resonance controlling. Here, the final model antenna is fabricated on an FR-4, and experimental results are compared with simulations.

Frequency and time domain analysis of a novel UWB antenna with dual band-notched characteristics

This paper presents the dual band notch characteristics of Ultra wideband (UWB) monopole antenna. Proposed antenna (30 × 30 mm2) consists of arrow shaped patch and truncated ground plane. Operating range of the proposed antenna (voltage standing wave ratio &lt; 2) is 2.2–11 GHz. In order to achieve dual band stop characteristics, λ/2 open ended angularly separated slit pair has been inserted on the radiator for world interoperability for microwave access (WIMAX) (3.3–3.9 GHz) band rejection performance and wireless local area network (WLAN) (5.1–5.9 GHz) band rejection has been realized by introducing a pair of angularly separated λ/2 conductor backed plane (CBP). Using proper adjustment of angular separation for both slit pair and CBP pair, enhanced band rejection can be achieved for the WIMAX and WLAN band, respectively. The performance of antenna has been investigated in terms of frequency domain and time domain to assess its suitability in UWB communication.

Compact Integrated Bluetooth UWB Antenna with Quadruple Bandnotched Characteristics

In this paper,a compact printed dualband antenna for Bluetooth and UWB applications with WiMax(3.3-3.7 GHz), C-band satellite downlink(3.7-4.2GHz), WLAN(5.15-5.825GHz) and DSRC(5.5-5.925GHz) bandnotched characteristics is proposed and investigated. By etching two half-wavelength L-shaped slots in the radiating patch and an inverted U-shaped slot in the microstrip feedline quadruple bandnotched characteristics is obtained. Further, by embedding quarter wavelength parasitic strip at two edges of U-shaped radiating patch dualband characteristics with desired bandwidth is obtained. the proposed antenna is designed and fabricated on a FR4 substrate of dimensions 24mm X 35mm that operates over a 2.4-11GHz with S11&amp;lt;-10dB except over notch bands of 3.3-3.7GHz, 3.7-4.2GHz,5.15-5.625GHz and 5.625-6GHz. Directional pattern in E-plane and nearly omnidirectional pattern in H-plane are observed over a UWB band except at desired bandnotched freqencies. Less variation in group delay and pulse deformation shows good time domain characteristics. In addition, the structure exhibits stable gain over the desired band.

Frequency Notched UWB Printed Monopole Antenna with Protruding Strips inside Rectangular Slot

In this paper, a printed Ultra Wide Band (UWB) antenna of small size with variable frequency band-notched properties is presented. Finite element based HFSS software is used to simulate the proposed antenna and then fabricated. The parameters of fabricated antenna are measured with E5071C vector network analyser. The measured and simulated results are in good agreement. A stepped radiating patch is printed on one side and stepped ground plane on the other side of FR- 4 substrate to increase the bandwidth from 4.3 GHz to 11.28 GHz. Introduction of two protruding strips having a length of λ/2 in rectangular slot results to get frequency notch characteristics in WLAN (5.15–5.85 GHz) band. The effects of length and thickness of individual protruding strips on band notch characteristics are examined. By varying either the length or the thickness of protruding strips incorporated in the rectangular slot, we can control the band notch frequency and its band width. The presented antenna has a small size of 12 x 18 x 1.6 mm3and reveals a steady gain throughout the UWB except at notched band of 4.9 GHz 6.1 GHz. The radiation pattern in the E-plane and H-plane is like a figure of eight.