Slot In Ground Plane Research Articles

Triple band notched mushroom and uniplanar EBG structures based UWB MIMO/Diversity antenna with enhanced wide band isolation

Triple band-rejection MIMO/Diversity UWB antenna characteristics are described in this paper. Proposed antenna discards worldwide interoperability for microwave access WiMAX band from 3.3 to 3.6 GHz, wireless local area network WLAN band from 5 to 6 GHz and X-Band satellite downlink communication band from 7.1 to 7.9 GHz. Mushroom Electromagnetic Band Gap (EBG) structures helps to attain band notches in WiMAX and WLAN bands. Uniplanar plus shaped EBG structure is used for notch in X-band downlink satellite communication band. Decoupling strips and slotted ground plane are employed to develop the isolation among two closely spaced UWB monopoles. The individual monopoles are 90° angularly separated with stepped structure which helps to reduce mutual coupling and also contributes towards impedance matching by increasing current path length. Mutual coupling magnitude of more than 15 dB is found over whole UWB frequency range. The Envelope Correlation Coefficient is less than 0.02 over whole UWB frequency range.The variations in the notched frequency with the variations in mushroom EBG structure parameters are investigated.The antenna has been designed using FR-4 substrate and overall dimensions is (64 × 45 × 1.6) mm3.

Miniaturized Spectacles Shaped Tapered Slotted Patch Antenna for UWB Applications

A compact planner patch ultra-wideband (UWB) antenna is presented in this paper. The antenna configuration consists of a spectacles-shaped patch and a slotted ground plane. Different parameters are investigated for improving the antenna’s properties and for achieving the preferred UWB band (3.1–10.6 GHz). The experimental and simulated results demonstrate that the proposed antenna acquires an operating bandwidth of 117% (3–11.5 GHz) with a stable omnidirectional radiation pattern, about 89% of average radiation efficiency and 4.2 dBi of average gain with the maximum of 5.7 dBi at 10.2 GHz.

Increasing Microstrip Patch Antenna Bandwidth by Inserting Ground Slots

Microstrip patch antenna (MPA) is widely implemented in different communication systems. One of the main disadvantages of MPA which limits its applications is its narrow bandwidth. In this paper I enhanced the bandwidth of MPA by inserting multiple slots in its ground plane. I used FR-4 substrate to design this antenna. The dimensions of this antenna are 59 mm and 79 mm. The dielectric constant is 4.4 and the height is 1.6 mm. I inserted up to 15 slots in ground plane with 1mm width. The spacing between slots is 3 mm. I investigated two designs. In the first design, slots were arranged in parallel to the feeding line. In the second one, slots were arranged horizontally to the feeding line. The main objective of this paper is to design and simulate MPA suitable for wide number of applications. Antenna bandwidth improvement is 18%. All the simulations were obtained by using HFSS simulator.

Textile Antenna With Simultaneous Frequency and Polarization Reconfiguration for WBAN

This paper proposes the design of a reconfigurable circularly polarized textile antenna. The circular polarization feature in the proposed antenna is generated by the edge truncation of a rectangular patch and the incorporation of a slotted ground plane, whilst the frequency reconfigurability feature is realized by slot size modification via the use of three embedded RF p-i-n diode switches. Consequently, the antenna operation can be switched between six frequencies (1.57, 1.67, 1.68, 2.43, 2.50, and 2.55 GHz) depending on the seven switch configurations. The proposed antenna is validated experimentally to be operable within the WBAN, WLAN, and GPS range in a compact and wearable format, with gains of up to 4.8 dBi.

A Novel Patch Antenna Design with Slotted Ground Plane for Satellite Communications

In this paper a microstrip patch antennais proposed for Ku-band satellite applications on the basis of its performance. The bandwidth of 6.12GHzhas been achieved with the help of parasitic patches, defected radiating patch and defected ground structure. The overall size proposed antenna is 16x8mm2.Four parasitic patches have been introduced and the antenna has obtained a return loss of 48.84dB at the center frequency of 16.77GHz. This antenna has been simulated using FR-4 substrate with dielectric constant of 4.3.Thisantenna can be used for satellite communications in Ku- Band.

Improvement in Depth of Return Loss of Microstrip Antenna for S-Band Applications

For S-band applications, a microstrip fractal antenna is designed by extending narrow impedance bandwidth into wide impedance bandwidth with use of partial ground plane. In the designed fractal antenna, the six elliptical slots in ground plane and two elliptical slots in radiating patch are embedded to improve the depth of return loss. Further, the parametric study is performed on width of microstrip feeding line, position/size of ellipses in radiating patch and ground plane to achieve mismatch loss [Formula: see text] 0.044[Formula: see text]dB and power delivered to antenna 99%, i.e., return loss [Formula: see text][Formula: see text]dB for S-band. The simulated antenna results are obtained using electromagnetic solver software and fabricated antenna results are measured using Vector Network Analyzer Bench MS46322A and they are found to be in good agreement.

Bandwidth enhancement of monopole antenna with DGS for SHF and reconfigurable structure for WiMAX, WLAN and C-band applications

In this study a reconfigurable antenna for WiMAX, WLAN, C-bands and SHF applications has been presented. The main body of antenna includes rectangular and L-shaped slotted ground plane and a rectangular patch with slotted feed line, for impedance bandwidth enhancement. In the proposed antenna, a PIN diode is used to adjust the frequency band to SHF, WiMAX, WLAN and C-bands applications. When PIN diode is forward-biased, the antenna covers the 3.5–31 GHz frequency range (i.e. a 160% bandwidth) and when the PIN diode is in its off-state, it operates between 3.4–5.8 GHz. The designed antenna, with a very small size of 12 × 18 × 1.6 mm3, has been fabricated and tested. The radiation pattern is approximately omnidirectional. Simulations and experimental results are in a good agreement with each other and suggest good performance for the presented antenna.

A Novel Hammer-Shaped UWB Antenna with Triple Notched-Band for Rejecting RLS, WLAN and XSCS bands

A novel hammer-shaped UWB printed antenna with triple notched stop bands is presented and fabricated on FR-4 substrate with size of 40×40×1.6 mm3. The proposed antenna is composed of hammer-shaped patch with C-shaped slot, U-shaped slot on feed line, and inverted stepped notch and bevel edges with pair of L-shaped slots in partial ground plane. The fabricated antenna is tested and obtained impedance bandwidth 2.89 ̶ 11.6 GHz with three notched stop bands 3.15 ̶ 3.7 GHz, 5.45 ̶ 6.8 GHz, and 7.5 ̶ 8.8 GHz, for radiolocation system (RLS), wireless local area networks (WLAN), and X-band satellite communication system (XSCS) bands, respectively. Moreover, the antenna result shows omnidirectional radiation pattern, average gain of 3.10 dBi over the whole UWB band except at the notched frequency bands.

A broadband circularly polarized cavity-backed Archimedean spiral array antenna for C-band applications

In this letter, a new configuration of sequentially rotated circularly polarized (CP) array antenna with a modified gain is investigated. In order to realize the presented antenna, four Archimedean spiral radiators are applied on a substrate, backed by a circularly slotted ground plane. Also a combination of 180° rat-race coupler and 90° branch-line couplers prepare the employed feeding network in this study. Furthermore, cavity-backed structure is utilized to enhance the antenna gain and achieve a directional radiation pattern over the operating frequency band. This configuration also extends the return loss (RL) and the axial ratio (AR) bandwidths, simultaneously. According to the experimental results, the 2×2 CP array antenna has RL bandwidth of 64.28%, AR bandwidth of 54.28%, and peak gain of 10.84dBic. The close correspondence between the measured and the simulated results validates the proposed design.

A compact elevated CPW-fed antenna with slotted ground plane for wideband applications

In this paper, a miniaturized elevated-coplanar-waveguide-fed antenna with a slotted ground plane is proposed. This antenna has a compact size of 25 mm × 25 mm × 1.6 mm where the ground plane is reduced by etching a trapezoidal slot along with two extended slits. A −10 dB wide-impedance bandwidth of 126% ranging from 2.8 to 12.4 GHz is achieved for the proposed antenna. The proposed antenna is successfully manufactured and experimentally investigated. The measurement shows a good agreement with the simulation. The measured radiation characteristic shows a stable and nearly omnidirectional pattern over the operating bandwidth region. The effects of various parameters on the antenna performance are analyzed and discussed as well.

A compact double-sided MIMO antenna with an improved isolation for UWB applications

This paper presents compact size 4×4cm2 MIMO antenna for UWB applications. The proposed antenna consists of four symmetric circular elements printed on low cost FR4 substrate with partial slotted ground plane. The two sides of the substrate are symmetric and each side is consisting of two radiators with the partial ground planes associated to the two other elements mounted on the other side. The two elements of the front side are orthogonal to the two other elements of the back side in order to increase the isolation between elements. For further reduction in the mutual coupling between elements, decoupling structures are presented in the top and bottom layers of the substrate. The simulated and measured results are investigated to study the effectiveness of the MIMO-UWB antenna. The results demonstrate the satisfactory performance of MIMO-UWB antenna, which has a return loss less than −10dB from approximately 3.1GHz to more than 11GHz with an insertion loss lower than −20dB through the achieved frequency band, and a correlation less than 0.002. Moreover, the proposed MIMO model exhibits a nearly omni-directional radiation pattern with almost constant gain of average value 3.28dBi.

Analysis Reconfigurable Frequency Textile Antenna in Bending Condition

In this paper, the analysis of reconfigurable frequency textile antenna in bending conditions is presented. The antenna consists of a truncated rectangular patch and slotted ground plane made by ShieldIt Super. Felt fabric is used as an antenna substrate. The proposed antenna is capable to reconfigure at seven different states frequencies by using three PIN diodes. The Circular Polarization (CP) is achieved at the GPS operating frequency. Meanwhile, the proposed antenna operates as a Linear Polarization (LP) at high operating frequencies. The performances of antenna in bending conditions is analyze since the textile antenna usually attached on the body will easily bend due to the human body structures. Details of the simulation results for antenna in bending condition are discussed.

A compact frequency‐reconfigurable fractal UWB antenna using reconfigurable ground plane

AbstractIn this article, a compact frequency reconfigurable ultrawideband (UWB) antenna having switchable multiple bands is presented. The reconfigurable multiple bands include UWB band, lower UWB band, middle UWB band, and one dual band having lower and upper UWB bands. Multiple p‐i‐n diodes are used in the slotted ground plane which helps to achieve frequency reconfigurability. The desired compactness and wider operational bandwidth is obtained in the antenna design with the help of Sierpinski fractal geometry. Moreover, it helps in enhancement of the radiation characteristics that assist us to get omnidirectional radiation pattern. It has a compact size of 24.5 mm × 20 mm.

Tripple-Band Microstrip Antenna for Wireless Application

This paper proposes a tripple-band microstrip antenna. The proposed antenna is designed to operate at Bluetooth (2.4–2.485 GHz), WiMAX (3.3–3.7 GHz) and WLAN (5.15–5.35 GHz, 5.725–5.825 GHz) bands. The antenna consists of a straight microstrip feed line and an inverted assymetric T shaped slot at ground plane. The microstrip feed line acting as quarter wave monopole is responsible for obtaining WiMAX band and the slot of ground plane is responsible for obtaining Bluetooth and WLAN band. The simulated and measured results have good agreement.

A New Compact Dual-band Antenna Based on Sierpinski Curve Slotted Ground Plane and Current Distribution Analysis

A new design approach has been used to achieve a dual band response from a multi-band resonance. The design approach is wholly depending on current distribution analysis on the surface of a multi-band antenna. The proposed multi-band antenna consists of a slotted ground plane with a simple 50-ohm microstrip feed line on the other side of an FR4 substrate having 4.4 relative dielectric constant and 1.6 mm thickness. The geometry of the first iteration Sierpinski curve fractal has been employed to the slotted ground plane antenna structure. Two small squares have been inserted to both internal upper corners of the slotted ground plane as a technique to control the path of electrical current on the surface of the multi-band antenna. With this technique, the resulted antenna can offer two resonating bands with respect to -10 dB S11. The first band (2.28-2.6) GHz, while the second band (5-5.58) GHz. The proposed antennas have been modeled and simulated using two softwares (CST Microwave Studio and High-Frequency Structure Simulation HFSS) to verify the results of both antennas and the other antenna parameters have been studied by using CST only.

Reducing frequency interference between two adjacent operating modes of a frequency reconfigurable antenna using π slotted ground plane

Reducing frequency interference between two adjacent operating modes of a frequency reconfigurable antenna using π slotted ground plane

A Compact UWB Bandpass Filter using Hybrid Fractal Shaped DGS

In this paper, a novel compact ultra wideband (UWB) bandpass filter (BPF) based on fractal-shaped defected ground structure is designed and developed with more than -20 dB out-of-band rejection level. It is made of stepped impedance line and composite right/left handed-transmission line (CRLH-TL) constructed with capacitive gap in conductor strip and a hybrid fractal-shaped ring slot in ground plane. The proposed UWB bandpass filter has good passband performance with -10 dB return-loss bandwidth of 2.2 GHz to 10.6 GHz with fractional bandwidth of 131%. The prototype of proposed filter is fabricated and measured. Good agreement is seen between simulated and measured results. The designed and developed filter is compact in size, simple in geometry and owns good S-parameters performance characteristics in both passband as well as in stopband. Return-loss better than 10 dB and insertion-loss less than 0.4 dB (except at some higher frequency) is obtained throughout the passband whereas, in stopband, insertion-loss more than 20 dB and return-loss better than 0.8 dB is observed up to the stopband frequency of 20 GHz. Moreover, UWB BPF also shows the flat group delay (variation ≤ 0.75 ns) performance. Thus the proposed filter can be a useful candidate for low profile future wireless communication systems.

Experimental study of a wearable aperture-coupled patch antenna for wireless body area network

A new type of the wearable aperture-coupled patch antenna for 2.4 GHz wireless body area network (WBAN) application is proposed. The H-shaped slot in middle ground plane and rectangular ring microstrip feed line are optimized, so that it realizes the efficient electromagnetic coupling with the radiating element. The substrate layers are 2 mm thickness felt layers with relative permittivity of 1.2, and the other layers are copper foil tape (CFT) to ensure the performance of the antenna. Furthermore, the return loss, radiation pattern and gain are investigated in detail for the antenna under different bending curvature radius. Experimental results show a good agreement with simulation results. (C) 2017 Wiley Periodicals, Inc.

Omnidirectional Circularly Polarized Dielectric Resonator Antenna With Logarithmic Spiral Slots in the Ground

A new omnidirectional circularly polarized (CP) cylindrical dielectric resonator (DR) antenna (DRA) is excited by four open-ended logarithmic spiral slots in the ground plane. Radiated E θ and E φ components are obtained from the TM 01δ mode of the DR and the slotted ground plane, respectively. Omnidirectional CP fields can be obtained when E θ and E φ are equal in magnitude but different in phase by 90°. This CP technique does not require any special shape or treatment of DR, greatly facilitating the design. To demonstrate the idea, a prototype using a glass DR was fabricated. It is a dual-function DRA that also serves as the cover of light sources. The prototype has a measured bandwidth of ~6.2%, covering the entire 2.4-GHz WLAN band.

Dual Band Notched EBG Structure based UWB MIMO/Diversity Antenna with Reduced Wide Band Electromagnetic Coupling

AbstractA dual band-notched MIMO/Diversity antenna is proposed in this paper. The proposed antenna ensures notches in WiMAX band (3.3–3.6 GHz) besides WLAN band (5–6 GHz). Mushroom Electromagnetic Band Gap (EBG) arrangements are employed for discarding interfering frequencies. The procedure followed to attain notches is antenna shape independent with established formulas. The electromagnetic coupling among two narrowly set apart Ultra-Wide Band (UWB) monopoles is reduced by means of decoupling bands and slotted ground plane. Monopoles are 90° angularly parted with steps on the radiator. This aids to diminish mutual coupling and also adds in the direction of impedance matching by long current route. S