Wi-Fi Applications Research Articles

Compact MIMO antenna using stepped impedance resonator‐based metasurface for 5G and WIFI applications

AbstractA compact metasurface‐based multiple‐input and multiple‐output (MIMO) antenna using the stepped impedance resonator (SIR) for 5G and WIFI applications is investigated in this article. The SIR patch unit‐cells are periodically etched on the two sides of a thin PCB substrate. As a result, the metal‐insulator‐metal (MIM) capacitor as the series left‐hand (LH) capacitor is introduced into the right‐handed transmission line (RH‐TL). Besides, the RH inductor could be easily adjusted through the SIR patch. Based on the dispersion relation of the metamaterial‐inspired SIR TL, a compact metasurface antenna is proposed and analyzed. A 3‐cell MIMO antenna with a reduced oversize of 0.48 λ0 × 1.34 λ0 × 0.05 λ0 (with λ0 being the free‐wavelength at 4.7 GHz.) for WIFI application is proposed and fabricated. Good agreement between measurement and simulation has been observed. Wide impedance bandwidth (covering 4.68‐5.75 GHz, 20.5%) and good isolation (all below −25 dB) are achieved. The measured peak gain and radiation efficiency are greater than 7.8 dBi and 90%, respectively. Owing to a compact antenna configuration, wide bandwidth (covering both 5G sub‐6GHz and WIFI bands), good radiation performance, and an easy fabrication process, this antenna is well suited for 5G or/and 5 GHz WIFI application in the base station.

DESIGN AND ANALYSIS OF T-STUB U-SLOT NOTCH BAND FREQUENCY RECONFIGURABLE ANTENNA USING PARAMETRIC ANALYSIS FOR WIRELESS COMMUNICATION APPLICATIONS

The design and analysis of a T-Stub U-Slot Frequency Reconfigurable Notch band antenna is considered in the present work using Coplanar Waveguide feed network for an efficient power transfer to improve the bandwidth characteristics of the antenna. The designed antenna has a dimension of 24X21X1.6 mm with FR4 substrate having a permittivity of 4.4. The proposed antenna consists of a T-Stub and U-Slots which are used to enhance the performance characteristics of the antenna. The reconfigurability is achieved by placing PIN diodes at T-Stub and U-Slots of the antenna design. The designed antenna is more suitable for WLAN, Wi-Fi, LTE and Bluetooth applications. Simulation results are obtained using CST tool and the same are presented at the end.

Routing Protocols in Vehicle Ad-Hoc Network

Vehicular Ad-hoc Network (VANET) is associate rising autonomous dynamic topology network. It is a unique type of Mobile Ad-hoc Network during which the automobiles amendment their message with each other. VANET turns every automobile in it into a mobile node and use those nodes to make a mobile dynamic community. The aim of VANET is to produce a wi-fi connectivity and numerous programs applications like collision dodging, safety and rising the traffic ratio as designing by the Intelligent Transportation System (ITS). The transport are strained by the sensible traffic surroundings, and currently the simulations are primarily network simulations that cannot simulate the real hint of the object (vehicle). Merely as nodes in VANETS have identical excessive mobility, so there are masses of demanding situation to route the packets to there final destination which need to be addressed by means of existing/offering new solutions for the comparable. Keeping view of above, In this paper, summarize the prevailing VANET routing protocols and classify and evaluate them. Then, listing numerous classic routing algorithms and examine their characteristics and advantages and disadvantages. Eventually, by way of analyzing the reputation of vehicle-installed routing protocols, we tend to illustrate the difficulties and challenges that vehicle-mounted routing protocols can/will encounter within the future.

Miniaturization of a Koch-Type Fractal Antenna for Wi-Fi Applications

Koch-type wire dipole antennas are considered herein. In the case of a first-order prefractal, such antennas differ from a Koch-type dipole by the position of the central vertex of the dipole arm. Earlier, we investigated the dependence of the base frequency for different antenna scales for an arm in the form of a first-order prefractal. In this paper, dipoles for second-order prefractals are considered. The dependence of the base frequency and the reflection coefficient on the dipole wire length and scale is analyzed. It is shown that it is possible to distinguish a family of antennas operating at a given (identical) base frequency. The same length of a Koch-type curve can be obtained with different coordinates of the central vertex. This allows for obtaining numerous antennas with various scales and geometries of the arm. An algorithm for obtaining small antennas for Wi-Fi applications is proposed. Two antennas were obtained: an antenna with the smallest linear dimensions and a minimum antenna for a given reflection coefficient.

A compact flexible textile artificial magnetic conductor-based wearable monopole antenna for low specific absorption rate wrist applications

AbstractA compact monopole antenna backed with a 1 × 2 textile-based artificial magnetic conductor (AMC) array is proposed. Textile was mainly selected for the AMC materials according to an investigation that took place between different AMC substrate materials, where it was settled that the textile one displayed the highest antenna gain and efficiency. The monopole antenna and the AMC, distanced apart by 5 mm, combined form the integrated design. It operates at 2.4 GHz, which was particularly selected as the resonant frequency for wirelessly sending the subject's symptoms data via Wi-Fi, with realized gain and total efficiency of 6.76 dBi and 88.4%, respectively, in free space. Separated by 3 mm from the specific anthropomorphic mannequin human hand model, it displays a realized gain and total efficiency of 4.06 dBi and 44.39%, respectively, in a flat condition. Furthermore, it exhibits a specific absorption rate (SAR) of 1.8 W/kg averaged over 10 g of tissue. When bent over the human hand model, it performs well and exhibits a maximum SAR of 0.521 and 0.406 W/kg, averaged over 1 and 10 g of tissues, respectively. As a result of such outcomes, the proposed integrated design can be nominated for wearable hand/wrist and Wi-Fi applications.

A Square Patch with L and Inverted L shaped slotted AMC structure for Wi-Fi Applications

To improve the antenna characteristics in terms of bandwidth, gain and its radiation characteristics without providing any phase reflections, Artificial Magnetic Conductor (AMC) are used in antenna designing. This paper initially designed AMC structure for 2.4GHz frequency. The proposed AMC structure consists of three L shaped and inverted L shaped slots and provides zero degrees phase reflection at 2.4GHz resonant frequency. This proposed AMC structure is incorporated on conventional micro strip square patch antenna and results are simulated in High Frequency Structure Simulator (HFSS) software. The Proposed AMC incorporated patch antenna, return loss is improved from -16.16dB to -31.75dB, VSWR is from 1.42 to 1.05, the band width is increased from 16.5 MHz to 348.1 MHz This design resonates at a frequency of 2.4GHz and applicable to Wi-Fi applications.

Modelling and Simulation of Compact Microstrip Patch Antenna for Wi-Fi Applications

Modelling and Simulation of Compact Microstrip Patch Antenna for Wi-Fi Applications

Design of Metamaterial Antenna for 2.4 GHz WiFi Applications

In this paper, Antenna is an evergreen field of research because of its never-ending demand in the modern communication era. In this paper metamaterial antenna is presented. “Meta” a Greek word defines “beyond” the materials provide properties beyond conventional materials. In this paper the metamaterial and micro patch antenna concepts are combined to improve the performance of the ordinary patch antenna. This metamaterial antenna is designed in FR4 Epoxy substrate with dielectric permittivity of 4.4, height of the substrate is 1.6 mm and loss tangent tan δ = 0.02 with a simple shape of rectangular patch of dimension 40 mm length and 30 mm width. This antenna is simulated in an integral based solver simulation software called CST Microwave studio v2018 and yielded best results such as return loss − 46.58 dB, VSWR 1.009 and bandwidth of 574 MHz, directivity is 3.379 dBi, gain is 3.23 dBi for the resonant frequency(fr) of 2.4 GHz. The feeding network is also designed for better integration in real time applications. This antenna is further fabricated and tested for the validation and obtained, VSWR 1.3, Return loss − 26 dB and Bandwidth of 200 MHz. This metamaterial antenna is suitable for 2.4 GHz WiFi applications.

Gain and Bandwidth Considerations for Microstrip Patch Antenna Employing U and Quad L shaped Slots with DGS and Parasitic Elements for WiMax / WiFi Applications

In this research article, a microstrip patch antenna for Wireless Applications is presented. Stage by stage, the antenna is modified to achieve the desired wideband characteristics. The final proposed antenna is a combination of U and Quad L shaped slots with L shaped DGS and U shaped dual parasitic elements. Parameters S11, bandwidth and gain of the antenna versions during each stage are noted and steps are taken to improve these parameters. The end result is a wideband microstrip patch antenna working in the frequency range of 4.75 GHz to 6.15 GHz with a bandwidth of 1.40 GHz. The peak gain observed is about 7.24 dB at 5.64 GHz frequency. Simulations are carried out using HFSS software. The obtained results show that the proposed antenna can be extensively for WiFi (4.9 GHz to 5.9 GHz) and WiMax (5.3 GHz to 5.8 GHz) Applications.

Gain and Bandwidth Considerations for Microstrip Patch Antenna Employing U and Quad L shaped Slots with DGS and Parasitic Elements for WiMax / WiFi Applications

In this research article, a microstrip patch antenna for Wireless Applications is presented. Stage by stage, the antenna is modified to achieve the desired wideband characteristics. The final proposed antenna is a combination of U and Quad L shaped slots with L shaped DGS and U shaped dual parasitic elements. Parameters S11, bandwidth and gain of the antenna versions during each stage are noted and steps are taken to improve these parameters. The end result is a wideband microstrip patch antenna working in the frequency range of 4.75 GHz to 6.15 GHz with a bandwidth of 1.40 GHz. The peak gain observed is about 7.24 dB at 5.64 GHz frequency. Simulations are carried out using HFSS software. The obtained results show that the proposed antenna can be extensively for WiFi (4.9 GHz to 5.9 GHz) and WiMax (5.3 GHz to 5.8 GHz) Applications.

A compact E-shaped antenna with C-shaped slots and a back-patch for multiband applications

Abstract We present the design of a tri-band E-shaped printed antenna with C-shaped slots. A Rectangular patch etched with an n-shaped slot is added at the back of the substrate to enhance the bandwidth and the return losses of the resonant bands - particularly, that of the second band. Our antenna is designed to operate at 1.51/2. 46/6.11 GHz. As can be observed from the experimental results, it has 10 dB bandwidths of 157 MHz (1.416 to 1.573 GHz) 358 MHz (2.221 to 2.579 GHz) and 367 MHz (5. 918 – 6. 285 GHz) The first two bands cover the LTE, Bluetooth, IEEE 802.15.4 ZigBee and IEEE 802.11 WLAN applications. The third resonant band covers the unlicensed 6 GHz band which is widely implemented in wireless power transmission, as well as, RFID and satellite communications. In order to ease wireless congestion, the 6 GHz band is also currently being considered by the FCC to be opened up for the use of WiFi applications. Our antenna is fabricated on a single-sided FR4-epoxy, and it constitutes a compact size of 34 mm × 36 mm × 1.6 mm or 0.17λ × 0.18λ times0.0081λ, (based on the 1.51 GHz lowest resonant frequency) The antenna exhibits omnidirectional radiation patterns at the three resonant bands.

Metamaterial Cell-Based Superstrate towards Bandwidth and Gain Enhancement of Quad-Band CPW-Fed Antenna for Wireless Applications.

A multiband coplanar waveguide (CPW)-fed antenna loaded with metamaterial unit cell for GSM900, WLAN, LTE-A, and 5G Wi-Fi applications is presented in this paper. The proposed metamaterial structure is a combination of various symmetric split-ring resonators (SSRR) and its characteristics were investigated for two major axes directions at (x and y-axis) wave propagation through the material. For x-axis wave propagation, it indicates a wide range of negative refractive index in the frequency span of 2–8.5 GHz. For y-axis wave propagation, it shows more than 2 GHz bandwidth of near-zero refractive index (NZRI) property. Two categories of the proposed metamaterial plane were applied to enhance the bandwidth and gain. The measured reflection coefficient (S11) demonstrated significant bandwidths increase at the upper bands by 4.92–6.49 GHz and 3.251–4.324 GHz, considered as a rise of 71.4% and 168%, respectively, against the proposed antenna without using metamaterial. Besides being high bandwidth achieving, the proposed antenna radiates bi-directionally with 95% as the maximum radiation efficiency. Moreover, the maximum measured gain reaches 6.74 dBi by a 92.57% improvement compared with the antenna without using metamaterial. The simulation and measurement results of the proposed antenna show good agreement.

Design of a Compact Microstrip Triple Independently Controlled Pass Bands Filter for GSM, GPS and WiFi Applications

An ultra-compact triple-band bandpass filter based on dual-mode quarter-wave resonator for GSM, GPS, and WiFi applications is presented in this study. The filter consists of three quarter-wave resonators assisting in controlling each passband independently. The first operating frequency band is obtained by the direct-feed resonator which acts as a source to load coupling for the inner two resonators which are operating at higher frequency bands. The outermost resonator is coupled to the inner loaded resonators, thus a pair of transmission zeros between each passband can be excited and hence high-frequency selectivity can be obtained. To miniaturize the overall size of the filter, all resonators are folded and are jointly connected through a common metallic via with the ground. The design has a symmetric structure therefore, even-odd mode analysis method is applied to obtain the three controllable operating frequency bands. The first operating band is centered at 850 MHz which caters for GSM applications, while the second and third frequency bands centered at 1.57 GHz and 2.4 GHz fall in the GPS and WiFi wireless applications. The filter with an ultra-compact size of 0.10 λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g</sub> × 0.09 λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g</sub> (0.009λ <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g</sub> ) despite feed lines (λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g</sub> is the waveguide length centered at 850 MHz) is designed, fabricated and measured for the purpose of validation. Both the simulated and measured results are in good agreement and endorse the design concept.

Characterization of CP Radiations in a Planar Monopole Antenna Using Tuning Fork Fractal Slot for LTE Band13/Wi-Max and Wi-Fi Applications

In this paper, a novel antenna design comprising planar monopole with fractal slot defected ground structure for circularly polarized radiation is proposed. In the proposed antenna geometry, circular polarization radiation characteristics are obtained by defecting the ground structure with fractal slot. In this approach, CP characteristics are achieved by intensifying the level of cross polar component of the linearly polarized antenna upto a certain level by means of fractal slot inserted in ground structure. Antenna prototype with third order iterative tuning fork shaped fractal slot is fabricated and tested for the validation of simulated results. Parametric studies are also performed to exemplify the process of CP radiations. From the simulated and measured results, it is confirmed that the proposed antenna can be proficiently produced 10 dB return loss bandwidth (BW) nearly ≈37.4%, while 3-dB AR bandwidth (ARBW) is 15.5%, respectively. The proposed antenna can be a credible applicant for LTE Band 13/cellular/PCS /ASW/WiMAX and Wi-Fi applications.

Microstrip rectangular patch antenna with comb shape slot

In this paper fractal geometry in comb shape is placed with a rectangular slit and circular slot. A DGS structure is applied on the ground which gives the result as improved performance. The radiating patch is designed on FR-4 substrate for 2.4 GHz frequency which is used for mobile and Wi-Fi application. Simulations are done on HFSS software. Return loss is achieved for comb shape antenna is 21.31 dB at 2.4 GHz frequency and 30.76 dB at 4.4 GHz frequency. After applying DGS technique return loss is achieved as 37.28 dB at 2.4 GHz frequency and 33.87 dB at 4.4 GHz frequency.

Reconfigurable Antenna for Wi-Fi and 5G Applications

The purpose of this paper is to design a reconfigurable antenna that operates in two frequencies bands: 2.4 GHz the frequency allocated to the Wi-Fi application and the 28 GHz frequency Band for 5G applications. The total size of the antenna is 30 × 26.5 mm2, it is printed on a FR-4 substrate with a dielectric constant of 4.4 and thickness of 1.6 mm. We used the commercially available software CST MICROWAVE STUDIO (electromagnetic simulator) which is based on the FDTD method, to simulate the reconfigurable antenna and to determine the electromagnetic characteristics of this antenna (S11, VSWR and directivity)

IEEE 802.11-Enabled Wake-Up Radio: Use Cases and Applications.

IEEE 802.11 is one of the most commonly used radio access technologies, being present in almost all handheld devices with networking capabilities. However, its energy-hungry communication modes are a challenge for the increased battery lifetime of such devices and are an obstacle for its use in battery-constrained devices such as the ones defined by many Internet of Things applications. Wake-up Radio (WuR) systems have appeared as a solution for increasing the energy efficiency of communication technologies by employing a secondary low-power radio interface, which is always in the active state and switches the primary transceiver (used for main data communication) from the energy-saving to the active operation mode. The high market penetration of IEEE 802.11 technology, together with the benefits that WuR systems can bring to this widespread technology, motivates this article’s focus on IEEE 802.11-based WuR solutions. More specifically, we elaborate on the feasibility of such IEEE 802.11-based WuR solutions, and introduce the latest standardization efforts in this IEEE 802.11-based WuR domain, IEEE 802.11ba, which is a forthcoming IEEE 802.11 amendment, discussing its main features and potential use cases. As a use case consisting of green Wi-Fi application, we provide a proof-of-concept smart plug system implemented by a WuR that is activated remotely using IEEE 802.11 devices, evaluate its monetary and energy savings, and compare it with commercially available smart plug solutions. Finally, we discuss novel applications beyond the wake-up functionality that IEEE 802.11-enabled WuR devices can offer using a secondary radio, as well as applications that have not yet been considered by IEEE 802.11ba. As a result, we argue that the IEEE 802.11-based WuR solution will support a wide range of devices and deployments, for both low-rate and low-power communications, as well as high-rate transmissions.

A Metamaterial-Based Compact Planar Monopole Antenna for Wi-Fi and UWB Applications.

Ultrawideband (UWB) antennas are widely used as core devices in high-speed wireless communication. A novel compact UWB monopole antenna with an additional narrow band for Wi-Fi applications comprising a metamaterial (MTM) is proposed in this paper. The antenna has a compact size of 27 × 33 mm2 and consists of a V-shaped slot with two rectangular slots in the radiation patch. The inductance and capacitance develop due to the V-shaped slot in the radiation patch. The proposed antenna has −10 dB bandwidths of 3.2 GHz to 14 GHz for UWB and 2.38 GHz to 2.57 GHz for narrowband, corresponding to 144% and 7.66% fractional bandwidths, respectively. The measured gain and efficiency meet the desired values for UWB and Wi-Fi applications. To verify the performance of the antenna, the proposed antenna is fabricated and tested. The simulated and measured results agree well at UWB frequencies and Wi-Fi frequencies, and the antenna can be used as a smart device for portable IoT applications.

The two-levels rectangular microstrip Yagi antenna for Wi-Fi application

An antenna is the most important part of a wireless communication system. Wi-Fi has an omnidirectional radiation pattern that results in a limited range of emissions. Therefore, it needs an external antenna with a higher gain than the internal antenna. This research designs rectangular Yagi microstrip antenna with two-levels of directors which can work at 2.4 GHz frequency (Wi-Fi Application). The selection of material permittivity value and dimension setting is committed carefully in order to gain > 5 dB. At the time of simulation, optimization is performed by changing the dimension of driven, director, reflector, and distance between levels. The realization of the antenna is committed by using dielectric material with relative permittivity of 4.3. The antenna test results show a bandwidth gain of 7.98 dB, S11 parameter of -16.223 dB with a bidirectional radiation pattern. By selecting the material permittivity value and prudence in managing the antenna dimensions, it is proven to produce an antenna with target gain although the antenna only uses 1 branch and 2-levels of directors.

A Tri-Band Shared-Aperture Antenna for (2.4, 5.2) GHz Wi-Fi Application With MIMO Function and 60 GHz Wi-Gig Application With Beam-Scanning Function

This article presents the design and the realization of a tri-band shared-aperture antenna operating at 2.4, 5.2, and 60 GHz. It puts these three bands of antennas within the same radiating aperture and then realizes the Wi-Fi application with MIMO function and the Wi-Gig application with beam-scanning function simultaneously. It consists of two dual-band printed inverted-F antennas (PIFAs) and two SIW leaky wave antennas. By using the structure-reused technology, PIFA for the Wi-Fi application and the SIW antenna for the Wi-Gig application can share the same radiator without adding an extra aperture area. Thus, the ratio of the radiating aperture utilization can be improved greatly. In addition, MIMO technology is also applied to the Wi-Fi antenna design. The envelope correlation coefficients (ECCs) calculated from the simulated and measured data are all lower than 0.04. The measured radiation efficiencies are 74% to 95% and 76% to 95% within these two bands, respectively. Moreover, due to the optimal layout of the whole design, the Wi-Gig antenna can obtain high gain and wide range of beam coverage at the same time. The measured peak gain is 12.29 dBi, and the beam coverage is ±36° from 57 to 64 GHz.