Antennas, Amplifiers and Propagation Topics (For Microwave Wlans)
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Performance Analysis of Helical Antenna for Different Physical Structure
International Journal of Innovative Research in Electronics and Communications (IJIREC) Volume 5, Issue 4, 2018, PP 21-25 ISSN 2349-4050 (Online) & ISSN 2349-4042 (Print) DOI: http://dx.doi.org/10.20431/2349-4050.0504004 www.arcjournals.org Performance Analysis of Helical Antenna for Different Physical Structure Rahul koshti1, Simran Yadav2, Shikha Sharma3 MPSTME, NMIMS, Shirpur *Corresponding Author: Rahul koshti, MPSTME, NMIMS, Shirpur Abstract: Wireless technology is such of the potent areas of scan in the presence of communication systems today and a design of communication systems is incomplete without a perspective of the activity and fabricatio n of antennas. Helical antenna is used as easily done and shrewd radiators completely the get by few decades, this antenna can be utilized as an encourage for an explanatory dish for higher additions.. So in this we have varied various parameters of helical antenna. Manipulations for this helical antenna antenna have been done with the assist of Matlab softwar Keywords: helical antennas, Antenna gain, Directivity. 1. INTRODUCTION In 1946 Kraus invented the helix form of antenna that is helical antenna. For longer period of time this helical antenna gets famous. [1] Helical antennas are further called as unfiled helix. By the all of diameter D in large helical antenna is revitalizing by a coaxial line along the little ground plane. In communication system helical antenna have a very large approach, so there is a foist of broadband circular polarized antennas [2].This antenna is most significantly used nowadays in point communications, telephone, and television and Information communication. The normal mode helical antenna is particularly attractive for mobile communication and adaptable equipment [3].The shape of helix antenna is a cross breed of two straightforward emanating essentials, the dipole and circle reception apparatuses. -
A Dual-Port, Dual-Polarized and Wideband Slot Rectenna for Ambient RF Energy Harvesting
A Dual-Port, Dual-Polarized and Wideband Slot Rectenna For Ambient RF Energy Harvesting Saqer S. Alja’afreh1, C. Song2, Y. Huang2, Lei Xing3, Qian Xu3. 1 Electrical Engineering Department, Mutah University, ALkarak, Jordan, [email protected] 2 Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool, United Kingdom. 3 Department of Electronic Science and Technology, Nanjing University of Aeronautics & Astronautics, Nanjing, China. Abstract—A dual-polarized rectangular slot rectenna is they are able to receive RF signals from multiple frequency proposed for ambient RF energy harvesting. It is designed in a bands like designs in [4-7]. In [4], a novel Hexa-band rectenna compact size of 55 × 55 ×1.0 mm3 and operates in a wideband that covers a part of the digital TV, most cellular mobile bands operation between 1.7 to 2.7 GHz. The antenna has a two-port and WLAN bands. Broadband antennas. In [7], a broadband structure, which is fed using perpendicular CPW and microstrip line, respectively. To maintain both the adaptive dual-polarization cross dipole rectenna has been designed for impedance tuning and the adaptive power flow capability, the RF energy harvesting over frequency range on 1.8-2.5 GHz. rectenna utilizes a novel rectifier topology in which two shunt (2) antennas for wireless energy harvesting (WEH) should diodes are used between the DC block capacitor and the series have the ability of receiving wireless signals from different diode. The simulation results show that RF-DC conversion polarization. Therefore, rectennas have polarization diversity efficiency is greater 40% within the frequency band of like circular polarization [7]; dual polarization [8] and all interested at -3.0 dBm received power. -
Enhancing the Coverage Area of a WI-FI Access Point Using Cantenna
ISSN 2394-3777 (Print) ISSN 2394-3785 (Online) Available online at www.ijartet.com International Journal of Advanced Research Trends in Engineering and Technology (IJARTET) Vol. 2, Issue 4, April 2015 Enhancing the Coverage Area of a WI-FI Access Point Using Cantenna B.Anandhaprabakaran#1, S.Shanmugam*2,J.Sridhar*3S.Ajaykumar#4 #2-4student #1Assistant Professor, Sri Ramakrishna Engineering College, Coimbatore, Tamilnadu, India Abstract: “The next decade will be the Wireless Era.” – Intel Executive Sean Maloney and other executives framed. Today’s network especially LAN has drastically changed. People expect that they should not be bound to the network. In this scenario, Wireless (WLAN) offers tangible benefits over traditional wired networking. Wi-Fi (Wireless Fidelity) is a generic term that refers to the IEEE 802.11 communications standard for Wireless Local Area Networks (WLANs). Wi-Fi works on three modes namely Ad hoc, Infrastructure and Extended modes. Ad hoc network is P2P mode. Ad hoc does not use any intermediary device such as Access Point. Infra Structure and Extended modes use Access Point as interface between wireless clients. The wireless network is formed by connecting all the wireless clients to the AP. Single access point can support up to 30 users and can function within a range of 100 – 150 feet indoors and up to 300 feet outdoors. The coverage area depends upon the location where the AP is being placed. The AP has the traditional Omni directional antenna The aim of this project is to increase the coverage area of an AP by replacing the traditional Omni directional antenna with Bi-quad antenna with parabolic reflector. -
Design of Narrow-Wall Slotted Waveguide Antenna with V-Shaped Metal Reflector for X
2018 International Symposium on Antennas and Propagation (ISAP 2018) [ThE2-5] October 23~26, 2018 / Paradise Hotel Busan, Busan, Korea Design of Narrow-wall Slotted Waveguide Antenna with V-shaped Metal Reflector for X- Band Radar Application Derry Permana Yusuf, Fitri Yuli Zulkifli, and Eko Tjipto Rahardjo Antenna Propagation and Microwave Research Group, Electrical Engineering Department, Universitas Indonesia Depok, Indonesia Abstract - Slotted waveguide antenna with wide bandwidth match to side lobe level requirement. Later, two metal sheets characteristics is designed at the 9.4-GHz frequency (X-band) as metal reflector are attached to the SWA edges to focus its for radar application. The antenna design consists of 200 narrow-wall slots with novel design of V-shaped metal reflector azimuth plane beam. The reflection coefficient, radiation to enhance side lobe level (SLL) and gain. New optimized slot pattern plots, and gain results of the antenna are reported. design results in SLL of -31.9 dB. The simulation results show 36.7 dBi antenna gain and 780 MHz bandwidth (8.67-9.45 GHz) for VSWR of 1.5. 2. Antenna Configuration Index Terms — slotted waveguide antenna, X-band, narrow- The 3-D view of the proposed antenna configuration is wall slots, high gain, metal reflector, radar shown in Fig 1. The antenna configuration consists of narrow wall slot waveguide with V-shaped metal reflector. The target frequency is 9.4 GHz. The slot antenna dimension 1. Introduction with its parameters is shown in Fig. 2. The antenna radiates Radar is essential component used for detecting hazards horizontal polarization and determines the parameters w = (such as coastlines, islands, icebergs, other objects or ships), 1.58 mm and t = 1.25 mm. -
Broadband Antenna 1
Broadband Antenna Broadband Antenna Chapter 4 1 Broadband Antenna Learning Outcome • At the end of this chapter student should able to: – To design and evaluate various antenna to meet application requirements for • Loops antenna • Helix antenna • Yagi Uda antenna 2 Broadband Antenna What is broadband antenna? • The advent of broadband system in wireless communication area has demanded the design of antennas that must operate effectively over a wide range of frequencies. • An antenna with wide bandwidth is referred to as a broadband antenna. • But the question is, wide bandwidth mean how much bandwidth? The term "broadband" is a relative measure of bandwidth and varies with the circumstances. 3 Broadband Antenna Bandwidth Bandwidth is computed in two ways: • (1) (4.1) where fu and fl are the upper and lower frequencies of operation for which satisfactory performance is obtained. fc is the center frequency. • (2) (4.2) Note: The bandwidth of narrow band antenna is usually expressed as a percentage using equation (4.1), whereas wideband antenna are quoted as a ratio using equation (4.2). 4 Broadband Antenna Broadband Antenna • The definition of a broadband antenna is somewhat arbitrary and depends on the particular antenna. • If the impendence and pattern of an antenna do not change significantly over about an octave ( fu / fl =2) or more, it will classified as a broadband antenna". • In this chapter we will focus on – Loops antenna – Helix antenna – Yagi uda antenna – Log periodic antenna* 5 Broadband Antenna LOOP ANTENNA 6 Broadband Antenna Loops Antenna • Another simple, inexpensive, and very versatile antenna type is the loop antenna. -
Revisiting Slot Antennas
Revisiting Slot Antennas Chris Hamilton AE5IT Rocky Mountain Ham Radio NerdFest 2021 Who am I? • AE5IT, formerly KD0ZYF • Licensed 2014 to call for help in the woods • Immediately became a weird RF nerd • Slot antennas captured attention early, but no real use cases Early 2020 – no-drill mobile • Could I load the gap between body panels as a slot antenna? • Construction & waterproofing challenges • Working without a VNA, lots of guessing • Surprisingly difficult to load • Radiation pattern and polarization not ideal (pretty good for overhead ISS passes) • Went directly for 2m / 70cm dual-band The rest of 2020 & early 2021 • EVERYTHING WAS NORMAL AND FINE AND NOTHING AT ALL WEIRD HAPPENED • Returning to ham projects after a lost year • Coincidentally a recent increased interest in slot antennas among hams So what is a slot antenna? • Literally a slot cut into a large metal sheet • Mathematical & physical complement to a dipole antenna • Radiation pattern resembles a dipole, but with E & H planes swapped -- a vertical slot is horizontally polarized • Feedpoint impedances inverse of dipole Where & why are they used? • Practical at V/UHF and above • Common in aviation, TV broadcast, telecom • Used for cell towers & microwave arrays • The metal plane can be a waveguide – the support structure is the antenna • Allows for electrically steerable beams in compact & robust packages Largely unknown by hams • Wildly impractical at HF • Horns and dishes give more gain in smaller packages • Applications for V/UHF weak signal? • Some applications for stealth antennas in restrictive neighborhoods • Some new designs seem to contradict the literature, or my understanding of it Current work • Fundamentals • Build from reference designs: Kraus, Johnson & Jasik • Measure & compare performance • Figure out my weird VNA • Perform replication studies of recent popular designs Let’s build antennas! Minimal resonant slot 26 AWG copper wire Center-fed Textbook slot λ x λ/2 Aluminum sheet λ/20-fed This is not a test & measurement talk. -
Helical Feed Manipulation for Parabolic Reflector Antenna Gain Control
International Journal of Engineering and Advanced Technology (IJEAT) ISSN: 2249 – 8958, Volume-4 Issue-2, December 2014 Helical Feed Manipulation for Parabolic Reflector Antenna Gain Control Zohair Mohammed Elhassan Hussein, Abdelrasoul jabar kizar alzubaidi Abstract Helical antennas have long been popular in A sketch of a typical helical antenna is shown in Figure (1). applications from VHF to microwaves requiring circular The radiating element is a helix of wire, driven at one end polarization, since they have the unique property of naturally and radiating along the axis of the helix. A ground plane at providing circularly polarized radiation. One area that takes the driven end makes the radiation unidirectional from the advantage of this property is satellite communications. Where far (open) end. There are also configurations that radiate more gain is required than can be provided by a helical antenna alone, a helical antenna can also be used as a feed for perpendicular to the axis, with an unidirectional pattern. a parabolic dish for higher gains. The helical antenna can be W e shall only consider the axial-mode configuration. an excellent feed for a dish, with the advantage of circular Typical helix dimensions for an axial-mode helical antenna polarization. One limitation is that the usefulness of the have a helix circumference of one wavelength at the center circular polarization is limited since it cannot be easily frequency, with a helix pitch of 12 to 14 degrees. Kraus reversed to the other sense, left- handed to right-handed or defines the pitch angle α as: vice-versa. This paper deals with applying an electronic technique to control the helical feed of the parabolic reflector = ………………..(1) feed. -
A Wide-Band Slot Antenna Design Employing a Fictitious Short Circuit Concept Nader Behdad, Student Member, IEEE, and Kamal Sarabandi, Fellow, IEEE
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, VOL. 53, NO. 1, JANUARY 2005 475 A Wide-Band Slot Antenna Design Employing A Fictitious Short Circuit Concept Nader Behdad, Student Member, IEEE, and Kamal Sarabandi, Fellow, IEEE Abstract—A wide-band slot antenna element is proposed as a experimental investigations on very wide slot antennas are building block for designing single- or multi-element wide-band or reported by various authors [2]–[5]. The drawback of these dual-band slot antennas. It is shown that a properly designed, off- antennas are two fold: 1) they require a large area for the slot centered, microstrip-fed, moderately wide slot antenna shows dual resonant behavior with similar radiation characteristics at both and a much larger area for the conductor plane around the slot resonant frequencies and therefore can be used as a wide-band and 2) the cross polarization level changes versus frequency and or dual-band element. This element shows bandwidth values up to is high at certain frequencies in the band [2]–[4], and [6]. This 37%, if used in the wide-band mode. When used in the dual-band is mainly because of the fact that these antennas can support mode, frequency ratios up to 1.6 with bandwidths larger than 10% two orthogonal modes with close resonant frequencies. The ad- at both frequency bands can be achieved without putting any con- straints on the impedance matching, cross polarization levels, or vantages of the proposed dual-resonant slots to these antennas radiation patterns of the antenna. The proposed wide-band slot ele- are their simple feeding scheme, low cross polarization levels, ment can also be incorporated in a multi-element antenna topology and amenability of the elements’ architecture to the design resulting in a very wide-band antenna with a minimum number of of series-fed multi-element broad-band antennas. -
Design of a Fractal Slot Antenna for Rectenna System and Comparison of Simulated Parameters for Different Dimensions
CPUH-Research Journal: 2015, 1(2), 43-48 ISSN (Online): 2455-6076 http://www.cpuh.in/academics/academic_journals.php Design of a Fractal Slot Antenna for Rectenna System and Comparison of Simulated Parameters for Different Dimensions Nitika Sharma 1*, B. S. Dhaliwal2 and Simranjit Kaur3 1, 2 & 3Department of Electronics and Communication Engineering, G. N. D. E. College, Ludhiana, India * Correspondance E-mail: [email protected] ABSTRACT: In the modern era we required a compact system having a high gain, efficiency and broad band- width. For rectenna (antenna + rectifier) system we need such an antenna which can receive more radio frequen- cies from the surroundings and gives to rectifier which works on one or more frequency band or multiband oper- ation. For fulfill these requirements we proposed a fractal slot antenna which gives multiband operation on 2.45 GHz. In this paper, we compare the simulation parameters on the basis of dimensions. Keywords: Rectenna; Multiband; Efficiency; Fractal Slot antenna and Gain. INTRODUCTION: Modern wireless applications antennas used as rectennas, microstrip patch antennas have challenged antenna designers with demands for are gaining popularity due to their low profile, light low-cost and compact antennas along with a simple weight, low production cost, simplicity, and low cost radiating element, signal-feeding configuration, good to manufacture using modern printed-circuit technol- performance, and easy fabrication. In the modern era, ogy [4]. the large reduction in power consumption achieved in Another reason for the wide use of patch antennas is electronics, along with the numbers of mobiles and their versatility in terms of resonant frequency, polari- other autonomous devices is continuously increasing zation, and impedance when a particular patch shape the attractiveness of low-power energy-harvesting [5] and mode are chosen . -
Various Types of Antenna with Respect to Their Applications: a Review
INTERNATIONAL JOURNAL OF MULTIDISCIPLINARY SCIENCES AND ENGINEERING, VOL. 7, NO. 3, MARCH 2016 Various Types of Antenna with Respect to their Applications: A Review Abdul Qadir Khan1, Muhammad Riaz2 and Anas Bilal3 1,2,3School of Information Technology, The University of Lahore, Islamabad Campus [email protected], [email protected], [email protected] Abstract– Antenna is the most important part in wireless point to point communication where increase gain and communication systems. Antenna transforms electrical signals lessened wave impedance are required [45]. into radio waves and vice versa. The antennas are of various As the knowledge about antennas along with its application kinds and having different characteristics according to the need is particularly less thus this review is essential for determining of signal transmission and reception. In this paper, we present various antennas and their applications in different systems. comparative analysis of various types of antennas that can be differentiated with respect to their shapes, material used, signal In this paper a detailed review of various types of antenna bandwidth, transmission range etc. Our main focus is to classify which developed to perform useful task of communication in these antennas according to their applications. As in the modern different field of communication network is presented. era antennas are the basic prerequisites for wireless communications that is required for fast and efficient II. WIRE ANTENNA communications. This paper will help the design architect to choose proper antenna for the desired application. A. Biconical Dipole Antenna Keywords– Antenna, Communications, Applications and Signal There is no restriction to the data transfer capacity of an Transmission infinite constant-impedance transmission line however any pragmatic execution of the biconical dipole has appendages of constrained extend forming an open-circuit stub in the same I. -
Wire Antennas for Ham Radio
Wire Antennas for Ham Radio Iulian Rosu YO3DAC / VA3IUL http://www.qsl.net/va3iul 01 - Tee Antenna 02 - Half-Lamda Tee Antenna 03 - Twin-Led Marconi Antenna 04 - Swallow-Tail Antenna 05 - Random Length Radiator Wire Antenna 06 - Windom Antenna 07 - Windom Antenna - Feed with coax cable 08 - Quarter Wavelength Vertical Antenna 09 - Folded Marconi Tee Antenna 10 - Zeppelin Antenna 11 - EWE Antenna 12 - Dipole Antenna - Balun 13 - Multiband Dipole Antenna 14 - Inverted-Vee Antenna 15 - Sloping Dipole Antenna 16 - Vertical Dipole 17 - Delta Fed Dipole Antenna 18 - Bow-Tie Dipole Antenna 19 - Bow-Tie Folded Dipole Antenna for RX 20 - Multiband Tuned Doublet Antenna 21 - G5RV Antenna 22 - Wideband Dipole Antenna 23 - Wideband Dipole for Receiving 24 - Tilted Folded Dipole Antenna 25 - Right Angle Marconi Antenna 26 - Linearly Loaded Tee Antenna 27 - Reduced Size Dipole Antenna 28 - Doublet Dipole Antenna 29 - Delta Loop Antenna 30 - Half Delta Loop Antenna 31 - Collinear Franklin Antenna 32 - Four Element Broadside Antenna 33 - The Lazy-H Array Antenna 34 - Sterba Curtain Array Antenna 35 - T-L DX Antenna 36 - 1.9 MHz Full-wave Loop Antenna 37 - Multi-Band Portable Antenna 38 - Off-center-fed Full-wave Doublet Antenna 39 - Terminated Sloper Antenna 40 - Double Extended Zepp Antenna 41 - TCFTFD Dipole Antenna 42 - Vee-Sloper Antenna 43 - Rhombic Inverted-Vee Antenna 44 - Counterpoise Longwire 45 - Bisquare Loop Antenna 46 - Piggyback Antenna for 10m 47 - Vertical Sleeve Antenna for 10m 48 - Double Windom Antenna 49 - Double Windom for 9 Bands -
Uni-Directional CPW-Fed Slot Antennas Using Loading Metallic Strips and a Widened Tuning Stub on Modified-Shape Reflectors
Uni-directional CPW-fed Slot Antennas Using Loading Metallic Strips and a Widened Tuning Stub on Modified-Shape Reflectors Sarawuth Chaimool 1, Prayoot Akkaraekthalin 1, and Monai Krairiksh 2 1 Department of Electrical Engineering, Faculty of Engineering, King Mongkut’s Institute of Technology North Bangkok, Bangkok 10800, Thailand, E-mail: [email protected] 2 Faculty of Engineering and Research Center for Communications and Information Technology King Mongkut’s Institute of Technology Ladkrabang, Bangkok 10520, Thailand Abstract We have observed that the size and shape of the conducting reflector of CPW-fed slot antennas using loading metallic strips and a widened tuning stub have significant impact on the antenna impedance matching and radiation pattern. By shaping the reflecting conductor, noticeable enhancements in both radiation pattern which provides uni-directional all frequency operating band and characteristic im- pedance matching are achieved. 1. INTRODUCTION The technique for reducing back radiation of the CPW-fed slot anten- nas is of interest due to it is possible place some type of conducting reflector behind the slot in order to reduce backside radiation and increase the gain. Among the several popular reducing back radiation techniques, a flat conducting reflector is easy in fabrication and most popular method for the electrically thick substrate CPW-fed slot antenna [1]. However, the presence of the flat conducting reflector Fig. 1: CPW-fed slot antennas using loading metallic strips and a widened may cause problems such as power leakage in the parallel-plate tuning stub (a) antenna element, above (b) flat reflector, (c) corner reflector, Λ modes which degrade impedance bandwidth and radiation pattern.