This paper presents the design and analysis of IoT (Internet of Things) controlled frequency reconfigurable triple-band antenna for WiMAX, ISM (Industrial, Scientific, and Medical) band, and X band microwave sensing applications. The designed antenna is constructed on polyimide substrate with a limited ground plane with compact dimensions of 27.5?×?8?×?0.6 mm3. The fabricated antenna is sensing the microwave signals that fall under WiMAX, ISM, & WLAN, and X band with a tunable frequency range of 3.2–3.9, 5.1–6.5, and 8.2–12 GHz, respectively. The operating frequency bands can be tuned by PIN diodes and which will be controlled by using the IoT-based NodeMCU module. The designed antenna resonates at 3.5, 5.9, and 8.45 GHz when the PIN diodes are in ON state and resonating at 3.79, 5.8, and 10.48 GHz when PIN diodes are in OFF state. The proposed antenna has bidirectional radiation at upper-frequency bands and unidirectional at lower frequency bands with gain ranging from 2.2 to 3.25 dB. The proposed frequency reconfigurable triple-band antenna has a more than 90% radiation efficiency at all the operating frequencies in the ON state. A good similarity between the measured (Antenna measurement setup with Vector Network Analyzer) and simulated results (CST Microwave Studio) is observed. In the real-time environment, the proposed reconfigurable antenna is tested by the CDAC (Centre for Development of Advanced Computing, India) Cmote unit found its suitability to microwave sensing applications.
相似文献In this paper, a rectangular triple-band microstrip antenna has been designed for Bluetooth application by successively loading notches and slots of different dimension in radiating patch. The conventional microstrip antenna suffers with narrow impedance bandwidth. The current work affords an alternate option to enhance the bandwidth of antenna that resonates in triple-band operation. Initially, the antenna is resonating in single-band but after loading slots, the bandwidth of microstrip antenna has been obtained 1.97% (lower band), 10.35% (middle band) and 33.16% (upper band) resonating in triple-band with three resonant frequency at 1.422 GHz (lower resonant frequency), 1.791 GHz (middle resonant frequency) and 2.467 GHz (higher resonant frequency). The suggested antenna has upper frequency band in the range of 2.045–2.858 GHz resonating at 2.467 GHz frequency and it is appropriate for Bluetooth applications (2.40–2.48 GHz) and both lower band useful for other wireless (L-band) applications. The return loss of upper band is ??34.52 dB at 2.467 GHz. The suggested microstrip antenna is directly fed by 50 ohm microstrip line feed. The suggested antenna has been designed, simulated and analyzed by IE3D simulation software.
相似文献The present research work aims towards the design of a stepped impedance resonator (SIR) based dual band antenna having resonant frequencies at millimeter wave: V band (center frequency: 60 GHz) and W band (center frequency: 94 GHz). The structure comprises of stepped impedance resonator (SIR) patch, two stepped section impedance matching network and a microstrip feedline. The fractional bandwidth of the proposed dual band antenna is 2.9 GHz (4.8%) and 6.25 GHz (6.6%) at 60 and 94 GHz, respectively. The far field polar plots show broadside radiation pattern having gain of 7.9 dBi at 60 GHz and 4.2 dBi at 94 GHz. Further, as a testimony of this concept, scaling principle was used and accordingly microwave scaled antenna was devised. The prototype scaled hardware results matched closely with the designed mm-wave antenna. Further, the proposed dual frequency antenna finds enormous applications towards development of pioneering millimeter wave systems like; 60 GHz is focused on multi gigabit WPAN communication and 94 GHz frequency is currently extensively used for millimeter wave imaging applications. The proposed design is very simple, conformal and easily extendable as an array for MMIC applications for compact frontend design.
相似文献In this article a modified hybridized fractal geometry i.e., fractal antenna is proposed for Multiple Input Multiple Output (MIMO) applications. These geometries are based on Minkowski curves and Koch curves located around the boundaries of the microstrip patch of rectangular-shaped patch. The hybridized model for fractal geometry is designed and analyzed on an FR4 substrate having a thickness of 1.47 mm for the Industrial, Scientific, and Medical (ISM) frequency band. But due to the proposed fractal geometry, it resonates at three bands (2.45 GHz, 3.67 GHz, and 5.88 GHz) and it is covering the ISM band from 2.42 GHz to 2.48 GHz with a VSWR value is 1.48. Further, a 2?×?2 antenna for MIMO application is proposed by considering identical antenna elements placed in parallel on the same substrate. MIMO antenna resonates at three frequencies as same as single antenna elements and covering the same operating bands. The two elements of MIMO confguration are simulated for various sets of distance values, and optimized distance is obtained 18 mm at which a proposed antenna provides low mutual coupling value, low Envelope Correlation Coefficient (ECC), and high diversity and peak gain. The calculated values of ECC and diversity gain are 0.0002 and 10 dB, respectively which satisfy the criteria of MIMO application. The design has been experimentally validated and an appropriate similarity of experimental and simulated results is achieved.
相似文献In this research work, a circularly polarized (CP) monopole antenna is designed for Ultra-Wideband (UWB) applications. The CP UWB antenna is be made up of a reformed ring patch and ground plane. The slots and stubs are inserted in the ground to achieve CP in the UWB antenna. This antenna attained an Axial Ratio Bandwidth (ARBW) of 5 GHz (4.0–9.0 GHz) that lies in the UWB frequency range that is from 3.1 to 10.6 GHz. The designed antenna has a radiation efficiency of around 80% for the complete UWB frequency range. The CP UWB antenna is designed and fabricated using the FR4 with a compact size of 32?×?30?×?1.6 mm3 and with a peak gain of 6.8 dBi. Tested results are in good resembles with simulated ones.
相似文献A compact wideband multi frequency microstrip antenna for wireless communication is proposed in this paper. The antenna is designed by introducing meandered slot on the patch and a pair of spur lines along the triangular notch on the finite ground plane. The overall size of the fabricated antenna is very small and low profile as the total dimension is 20?×?16 mm2. The proposed antenna operates at 3.7 GHz, 4.27 GHz and 5.1 GHz which may be suitable for WiMAX and WLAN applications. In addition with multi frequency operation a wide bandwidth (VSWR?≤?2) has been achieved from 6 to 13.7 GHz i.e. 78.2% bandwidth of center frequency, which is suitable for X-band communication and ITU band applications. The meandered slot on the patch causes multi frequency operation of the antenna with 60% compactness and the spur line along with triangular notch on finite ground plane cause bandwidth enhancement.
相似文献A compact multiband cavity-backed substrate integrated waveguide (SIW) and metamaterial antenna with coplanar waveguide (CPW) feed is designed for S and Ku bands thereby providing low and high frequency applications. Designing simultaneous achievement of high gain in S band and Ku band antennas are challenging task, but the proposed antenna overcomes this limitation. The proposed antenna has a ground structure with radiating T-shaped stub opposite to the feed line and a combination of SIW and metamaterial. SIW and complementary square split ring resonator (CSSRR) are used to enhance efficiency, directivity, gain and bandwidth. The proposed antenna structure uses FR-4 epoxy as the substrate material with ?r?=?4.4 with a dimension of 40 × 40?×?1.6 mm and analyzed using ANSYS HFSS. The designed antenna resonates at three frequencies (i.e.), 4.23, 13.63 and 17.05 GHz with a gain greater than 5 dBi and efficiency greater than 80%. It is suitable for S band (ISM, WLAN, WiMax) and Ku band (radar, satellite communications) applications. The designed antenna is linearly polarized with high gain and efficiency at both the bands.
相似文献A compact rectangular microstrip-fed Ultra Wideband patch antenna with double band notched feature at Wi-Max and WLAN is offered in this paper. The designed antenna is composed of an ordinary rectangular patch antenna with a partially defective ground structure. For achieving dual notch characteristics a ‘U’ and ‘Reversed U’ slots are embedded in the radiating patch. The partial ground plane structure with U shaped slot in the middle is incorporated for achieving additional resonance and bandwidth enhancement. The proposed antenna has a measurement of 20 × 33 × 1.6 mm3. First notch created by U shaped slot at frequency 3.5 GHz is for Wi-Max (from 2.9 to 4.5 GHz) and Second notch which is generated by Reversed U shaped slots at frequency 5.4 GHz is for WLAN (from 5.49 to 6.45 GHz). The antenna covers almost complete range of Ultra Wideband (3.1–10.6 GHz). The Simulation analysis of the proposed antenna is carried out using CST-2011 simulation software. The radiation pattern of the simulated antenna is near Omnidirectional and the Gain of proposed antenna is almost stable over the range of UWB excluding notch bands.
相似文献Herein, a Conductor Backed Co-Planar Waveguide fed, compact, slotted Multiple–Input–Multiple–Output or MIMO antenna having Super Wideband (SWB) response and tunable band-notching feature is presented. In addition, an improved method for cut-off frequency prediction of the antenna is formulated. A super wide frequency response from 01.21 to 34.0 GHz and notches at Wireless Local Area Networks or WLAN bands (04.92–05.83 GHz) and Worldwide Inter-operability for Microwave Access or WiMAX bands (03.30 GHz–03.70 GHz) are obtained. By fine tuning the dimensions of the Split Ring Resonator Structure introduced in the radiating element, band-notched characteristics centered at 05.50 GHz WLAN band is obtained. A second band notch having centre frequency at 03.50 GHz for the WiMAX band is obtained by the introduction of a Spiral Microstrip Defected Structure in the feeding segment. The antenna is 20?×?36?×?1 mm3 in dimension. Acceptable gain all through the functional bandwidth, excepting the notched bands makes the MIMO antenna a novel contender for SWB operations particularly for Wireless Personal Communications.
相似文献This article presents a compact Co-Planar Waveguide (CPW) fed antenna for next-generation Vehicular Communications. The antenna is designed by employing two rectangular stacked patch structures and slots, making the antenna resonate at dual frequency bands. The analytical study of antenna design is carried out using the governing microstrip patch equations. On optimizing the patch's dimensions for CPW structures, the desired frequency range of operation is obtained for the single element antenna structure. The designed antenna resonates at 3.5 GHz (LTE-42 Band) and 5.9 GHz (DSRC Band), yielding this antenna to be a prime component for Vehicular to Everything (V2X) Communication. The optimized single-element antenna structure is 35 mm?×?20 mm designed on an FR-4 substrate of thickness 1.6 mm. The substrate has a dielectric constant of 4.4 and a loss tangent value of 0.001. Further, the antenna structure is developed as a 4-element MIMO configuration with the distance between adjacent antenna elements to be 10 mm. The adjacent antennas in the MIMO configuration are positioned orthogonal to each other, thereby exhibiting better isolation between the antenna elements. The antenna has a reflection coefficient value of?<??10 dB within the bandwidth of interest and VSWR less than 2. The Gain value of the designed antenna ranges between 2.8 and 2.9 dBi at 3.5 GHz and between 3.6 and 3.7 dBi at 5.89 GHz. The overall efficiency of the antenna element is between 60 and 80% at both frequency bands. MIMO parameters are analyzed by calculating the Channel Capacity Loss (CL), Diversity Gain (DG), Envelope Correlation Coefficient (ECC) and Total Active Reflection Co-Efficient (TARC). The designed antenna is fabricated and tested, which shows the measured results coincide with the simulated antenna results. The overall dimension of the MIMO configured antenna design is 60 mm × 60 mm × 1.6 mm, which is highly compact and is a suitable candidate for deployment of Vehicle to Vehicle (V2V), Vehicle to Infrastructure (V2I), and Vehicle to Network (V2N) scenarios.
相似文献This paper proposes the design of three compact antennas for WiMAX, WLAN and ISM band applications. Antenna 1 consists of a monopole radiating element with an electromagnetic band gap (EBG) structured ground. By employing the EBG structure, an ultra-wide band frequency of 2.4–4.8 GHz (66.66%) is achieved. Antenna 2 is configured with an electric-LC (ELC) element, which achieved an ultra-wide band (UWB) frequency of 2.38–4.91 GHz (69.41%). Antenna 3 is integrated with ELC and EBG together, in which a UWB frequency of 2.3–5.3 GHz (78.94%) is obtained with improved impedance matching. The three antennas have omnidirectional radiation patterns which cover the ISM band at 2.4 GHz and WiMAX at 2.5/3.5 GHz over the operating bands. The radiation efficiency is?>?75% throughout the operating bands of all the antennas. In addition to the WiMAX and ISM bands, antenna 3 covers WLAN in the 5.2 GHz band. The proposed design can be applied to wireless mobile communication systems, which have the advantage of ease of fabrication and compactness.
相似文献This article proposed a compact dual-element MIMO (multiple-input-multiple-output) antenna system working in 1.575 GHz (Global Positioning System)/4.5 GHz (5G)/5.8 GHz (Wireless Local Area Network)/6.4 GHz (Satellite communication) with relatively high isolation. The proposed antenna element consists of compact inverted-F antenna with meandered arm. One side of the T-shaped monopole antenna is extended and meandered while the other side is grounded to form the IFA structure. Meandering of the arm is responsible for the quad-band response. The proposed structure is simulated and fabricated on a FR4 substrate with an overall dimension of (0.23 λ0?×?0.09 λ0?×?0.004 λ0) and edge-to-edge separation of the two patches is 0.04 λ0, where λ0 is the wavelength at lower resonating frequency (1.575 GHz) of the proposed antenna. The high isolation is achieved by incorporating two inverted L-shaped strips and a narrow slot in the ground plane. Envelope correlation co-efficient (ECC) and channel capacity loss (CCL) are within their acceptable limits. Other different diversity parameters are evaluated and the results are satisfactory for MIMO applications.
相似文献This article presents the design and development of a compact broadband “+” shaped aperture coupled carpet fractal antenna with a defected ground structure (I shaped slot in the ground) for broadband/ultra wideband (UWB) and a multiband characteristics. The antenna has overall dimensions of 8.4 cm?×?5.5 cm?×?3.2 mm and is fed using aperture coupled feeding mechanism. It shows an impedance bandwidth (<?10 dB) of 4460 MHz from 6.93 to 11.39 GHz with fractional bandwidth of 0.48 at the center resonant frequency of 9.16 GHz. A multiband behavior is also exhibited by this antenna from 3.9–4.08 GHz, 4.8–5.06 GHz and 6.1–6.4 GHz with impedance bandwidths of 180 MHz, 260 MHz and 300 MHz respectively. It therefore supports the wireless applications of Wi-MAX (3.8–4.1 GHz), Wi-BAN/long distance radio telecommunication (4.8–5.06 GHz), wireless sensor networks (6.1–6.4 GHz), satellite (7.4–7.8 GHz) and UWB (6.9–11.03 GHz). The antenna is designed as a ‘+’ shaped patch with fractal rectangular slots cut out from it up to iterations of second order that allow the antenna to support multiband characteristics. The bandwidth at these bands is improved by using I shaped defected ground structure (DGS) and a parasitic feeding method i.e. aperture coupled feeding (Karur et al., in: ICMARS (IEEE), Jodhpur, India, pp. 266–270, 2014).The antenna has a compact structure with two layers of FR4 substrate, the ‘+’ shaped carpet fractal printed on the upper substrate layer and the lower substrate has a ground layer printed on its top and feed line on its bottom layer respectively. It shows a simulated peak gain of 4 dB at an operation frequency of 7.95 GHz. The antenna design and simulations are done using CST MWS V14. The Simulation results in terms of impedance bandwidth, smith chart, gain are presented in this article. To validate the impedance bandwidth results, the proposed carpet fractal antenna is experimentally tested using a vector network analyzer and the measured results are found to be closely matching with the simulated ones, allowing the antenna to be practically suitable for the afore mentioned wireless applications.
相似文献In this paper, a compact, lightweight, low-profile dual-band circularly polarized antenna is presented for handheld radio frequency identification (RFID) readers. The proposed antenna consists of two concentric hexagonal rings and a feed network printed on different layers of the dielectric substrate. The antenna configuration exploits a stacked-coupled technique for gain enhancement and single-port feeding for easy manufacturing. The center frequencies of the two resonating bands are 0.92 GHz (UHF) and 2.45 GHz (ISM). The antenna exhibits circular polarization characteristics in both the resonating bands, therefore encountering the losses due to polarization mismatch and increasing the tag detection reliability. A prototype of the proposed RFID antenna is simulated and fabricated, and experimental results are in close agreement. The peak antenna gain is 3.3 dB and 5 dB in the UHF and ISM bands, respectively. The overall size of the RFID antenna is 80 mm?×?80 mm?×?7.76 mm.
相似文献In this paper, small printed flower-shape triple notch ultra-wideband (UWB) monopole antenna with high band rejection is presented. Notch bands include WiMAX (IEEE802.16 3.30–3.80 GHz), WLAN IEEE802.11a/h/j/n (5.15–5.35, 5.25–5.35, 5.47–5.725, 5.725–5.825 GHz), and X-band downlink satellite system (7.1–7.9 GHz). By including inverted T-shape stub and etching two C-shaped slots on the radiating patch, triple band-notch function is obtained with measured high band rejection (VSWR = 14.52 at 3.58 GHz, VSWR = 15.88 at 5.69 GHz and VSWR = 6.95 at 7.61 GHz) and covers a UWB useable fractional bandwidth of 114.30% (2.74–10.57 GHz = 7.83 GHz). In short the antenna offers triple band-notch UWB systems as a compact multifunctional antenna to reduce the number of antennas installed in wireless devices for accessing multiple wireless networks with wide radiation pattern. The proposed antenna has a small size of about 0.25λ × 0.30λ at 4.2 GHz (first resonance frequency), which has a size reduction of 30% with respect to the earlier published antenna. Both the experimental and simulated results of the proposed antenna are presented, indicating that the antenna is a good candidate for various UWB applications.
相似文献This paper presents a designing of dual-coated miniaturized metamaterial inspired quad band antenna for wireless standards with gain enhancement. Proposed design has compactness in size with electrical dimension of 0.239?×?0.351?×?0.0127 λ (30?×?44?×?1.6 mm3), at lower frequency of 2.39 GHz. The antenna consist a double printed slotted hexagonal shape radiating section with implementation of metamaterial rectangular split ring resonator. Antenna achieve quad bands for wireless standards WLAN (2.4/5.8 GHz), WiMAX (3.5 GHz), IEEE 802.11P (WAVE-5.9 GHz), ITU assigned X bands (7.25–7.75, 7.9–8.4 GHz) and satellite communication systems operating bands (C-band: 7.4–8.9 GHz and X-band: 8–10 GHz for satellite TV). An acceptable gain, stable radiation characteristics and good impedance matching are observed at all the resonant frequencies of the proposed structure. By application of proposed frequency selective surface an average enhancement of gain is about 4–5 dB over the operating band. Antenna fabricated and tested represent good agreement between the simulated and measured results.
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