The polarisation specification for an antenna specifies how the electric field behaves in the far field (where the radiated wave has established itself).
Antenna parameters part 1: Frequency bands, Gain and Radiation PatternAndre Fourie
This is part of an internal document that that gives an overview of the properties of antennas for non-engineers.
We have divided the document into different posts where we discus each of the parameters:
Frequency bands, gain and radiation pattern
Polarisation
Input Impedance and VSWR
Port to port Isolation and Cross-polarisation
Power Handling ability
Antenna “Specmanship”
Where applicable we have added some videos explaining the properties discussed.
Antenna parameters part 3 - Input impedance and VSWRAndre Fourie
VSWR stands for Voltage Standing Wave Ratio, and is also referred to as Standing Wave Ratio (SWR)The input impedance of an antenna per se is not usually reported directly in the brochure; rather the antenna’s nominal impedance and its VSWR are given. The nominal impedance is the impedance for which the antenna is (ideally) designed and the VSWR can be “seen” as the antenna’s deviation from this value.
The VSWR (voltage standing wave ratio) is a parameter that is derived from the antenna’s input impedance and the reported nominal impedance. One can view the VSWR as “how far” the antennas input impedance is from the nominal impedance. If the VSWR at a particular frequency is given as 1:1, then you can deduce that the antenna input impedance is equal to the nominal impedance. The higher the VSWR the further the antenna input impedance is from the nominal impedance.
An antenna array (or array antenna) is a set of multiple connected antennas which work together as a single antenna, to transmit or receive radio waves. The individual antenna elements are connected to a single receiver or transmitter by feedlines that feed the power to the elements in a specific phase relationship. The radio waves radiated by each individual antenna combine and superpose, adding together (interfering constructively) to enhance the power radiated in desired directions, and cancelling (interfering destructively) to reduce the power radiated in other directions. Similarly, when used for receiving, the separate radio frequency currents from the individual antennas combine in the receiver with the correct phase relationship to enhance signals received from the desired directions and cancel signals from undesired directions.
hello readers i give my PPT presentation for about antenna and ther properties and working explain in this ppt
i hope you like it THANK YOU.......!!!!!!!
Antenna parameters part 1: Frequency bands, Gain and Radiation PatternAndre Fourie
This is part of an internal document that that gives an overview of the properties of antennas for non-engineers.
We have divided the document into different posts where we discus each of the parameters:
Frequency bands, gain and radiation pattern
Polarisation
Input Impedance and VSWR
Port to port Isolation and Cross-polarisation
Power Handling ability
Antenna “Specmanship”
Where applicable we have added some videos explaining the properties discussed.
Antenna parameters part 3 - Input impedance and VSWRAndre Fourie
VSWR stands for Voltage Standing Wave Ratio, and is also referred to as Standing Wave Ratio (SWR)The input impedance of an antenna per se is not usually reported directly in the brochure; rather the antenna’s nominal impedance and its VSWR are given. The nominal impedance is the impedance for which the antenna is (ideally) designed and the VSWR can be “seen” as the antenna’s deviation from this value.
The VSWR (voltage standing wave ratio) is a parameter that is derived from the antenna’s input impedance and the reported nominal impedance. One can view the VSWR as “how far” the antennas input impedance is from the nominal impedance. If the VSWR at a particular frequency is given as 1:1, then you can deduce that the antenna input impedance is equal to the nominal impedance. The higher the VSWR the further the antenna input impedance is from the nominal impedance.
An antenna array (or array antenna) is a set of multiple connected antennas which work together as a single antenna, to transmit or receive radio waves. The individual antenna elements are connected to a single receiver or transmitter by feedlines that feed the power to the elements in a specific phase relationship. The radio waves radiated by each individual antenna combine and superpose, adding together (interfering constructively) to enhance the power radiated in desired directions, and cancelling (interfering destructively) to reduce the power radiated in other directions. Similarly, when used for receiving, the separate radio frequency currents from the individual antennas combine in the receiver with the correct phase relationship to enhance signals received from the desired directions and cancel signals from undesired directions.
hello readers i give my PPT presentation for about antenna and ther properties and working explain in this ppt
i hope you like it THANK YOU.......!!!!!!!
A loop antenna has simple structure but its analysis is not easy to perform. Since a loop antenna is a dual pair of a dipole antenna, we can adopt the analysis of a dipole for a loop based on the duality theorem. By stacking a number of loops, we can increase the antenna gain and radiation resistance very easily.
Broadside Array vs end-fire array
Higher directivity.
Provide increased directivity in
elevation and azimuth planes.
Generally used for reception.
Impedance match difficulty in
high power transmissions.
Variants are:
Horizontal Array of Dipoles
RCA Fishborne Antenna
Series Phase Array
This document contains all the necessary basic information to understand Antenna Basics with simple and to the point non mathematical description.
This document is suitable for those who wants to understand only basics of antenna wireless communication.
For any queries or suggestions please contact on : mansithakur0304@gmail.com
Contents:
Electromagnetic Spectrum and RF basics.
Antenna introduction and its parameters.
Some other important factors like radiation pattern and polarization
Types of antennas and mobile antenna designs
How radio wave propagates
In our daily life we see so many antennas everywhere, from simple radio transreceiver to big tower antennas and DTH antennas. Antenna is a magical element in the field of communication. Nobody can dream of wireless communication without the use of antennas. It’s the antenna which creates the magic in the air and makes wireless communication possible.
In this paper authors will discuss about the cellular antennas. They will concentrate mainly on fundamentals of antenna, relationship between frequency, wavelength and dipole wave propagation and parameters of antenna like Gain, VSWR, SFR and FBR etc.
Authors also discuss about types of down tilt, generic requirements of antennas, selection of antennas and beam forming and active antenna systems.
A loop antenna has simple structure but its analysis is not easy to perform. Since a loop antenna is a dual pair of a dipole antenna, we can adopt the analysis of a dipole for a loop based on the duality theorem. By stacking a number of loops, we can increase the antenna gain and radiation resistance very easily.
Broadside Array vs end-fire array
Higher directivity.
Provide increased directivity in
elevation and azimuth planes.
Generally used for reception.
Impedance match difficulty in
high power transmissions.
Variants are:
Horizontal Array of Dipoles
RCA Fishborne Antenna
Series Phase Array
This document contains all the necessary basic information to understand Antenna Basics with simple and to the point non mathematical description.
This document is suitable for those who wants to understand only basics of antenna wireless communication.
For any queries or suggestions please contact on : mansithakur0304@gmail.com
Contents:
Electromagnetic Spectrum and RF basics.
Antenna introduction and its parameters.
Some other important factors like radiation pattern and polarization
Types of antennas and mobile antenna designs
How radio wave propagates
In our daily life we see so many antennas everywhere, from simple radio transreceiver to big tower antennas and DTH antennas. Antenna is a magical element in the field of communication. Nobody can dream of wireless communication without the use of antennas. It’s the antenna which creates the magic in the air and makes wireless communication possible.
In this paper authors will discuss about the cellular antennas. They will concentrate mainly on fundamentals of antenna, relationship between frequency, wavelength and dipole wave propagation and parameters of antenna like Gain, VSWR, SFR and FBR etc.
Authors also discuss about types of down tilt, generic requirements of antennas, selection of antennas and beam forming and active antenna systems.
[Note: The Presentation may appear distorted in SlideShare website. It is not. Download it for the best view results. ]
This Presentation tries to cover Beam forming, beam steering & beam with changes subtopic for RADAR systems.
This PPT was made for Internal Assessment seminar for 18ECOE07- Open Elective I- Introduction to Radar systems- 7th semester, Jain (Deemed-to-be) University, Bengaluru India by Chaitanya Shukla (19BTRAS051)
Antennas in practice - EM fundamentals and antenna selectionAndre Fourie
This book “Antennas in Practice” has been in existence in a multitude of forms since about 1989. It has been run as a Continuing Engineering Education (CEE) course only sporadically in those years.
It has been revamped on several occasions, mainly reflecting changing typesetting and graphics capabilities, but this (more formal) incarnation represents a total re-evaluation, re-design and re-implementation. Much (older) material has been excised, and a lot of new material has been researched and included.
Wireless technology has really moved out of the esoteric and into the commonplace arena. Technologies like HiperLAN, Bluetooth, WAP, etc are well known by the layman and are promising easy, wireless “connectivity” at ever increasing rates. Reality is a little different and is dependent on a practical understanding of the antenna issues involved in these emerging technologies.
Although a fair amount of background theory is covered, its goal is to provide a framework for understanding practical antennas that are useful. Many design issues are covered, but in many cases, the “cookbook” designs offered in this book are good-enough starting points, but still nonoptimal designs, only achievable by simulation, and testing.
As a result, the book places a fair amount of emphasis on antenna simulation software, such as SuperNEC. Ordinarily, if this book is run as a CEE course, it is accompanied by a SuperNEC SimulationWorkshop, a hands-on introduction to SuperNEC. It is only through “playing” with simulation software that a gut feel is attained for many of the issues at stake in antenna design.
Alan Robert Clark
Andre P C Fourie
Version 1.4, December 23, 2002
Poynting recently launched a new Omni-directional antenna that is custom made for use on boats. The antenna covers the GSM, UMTS, WCDMA, Wi-Fi and 4G/ LTE bands and is future-proof, thanks to its inclusion of the new 450 MHz ranges. Marine antenna.
Poynting antenna setting sail for the Rio Olympics - DataweekAndre Fourie
The German Olympic sailing team will use Poynting's cutting edge OMNI-291 marine and coastal antenna for its land to vessel communication during the 2016 Summer Olympic games.
Die antenna help uitsaai. Artikel in Die BurgerAndre Fourie
Poynting Antennas het die antenna wat in die Bloodhound supersoniese motor se stertvin inpas ontwerp. Poynting ontwerp en verkoop antennas wat jou internet spoed verbeter. Hulle is gebasseer in Midrand en Kaapstad. Meer info en pryse by www.antennas.co.za.
Bloodhound se antenna in Suid-Afrika gemaak - artikel in Die VolksbladAndre Fourie
Poynting Antennas het die unieke antenna wat in die Bloodhound supersoniese motor se stertvin inpas ontwerp. Poynting ontwerp en verkoop antennas wat jou internet spoed verbeter. Hulle is gebasseer in Midrand en Kaapstad. Meer info en pryse by www.antennas.co.za.
Rocketship Radio - Popular Mechanics - Feb 2016Andre Fourie
Find this article in the February 2016 edition of the South African Popular Mechanics. It gives a great overview of the innovative technology that went into the antenna designed by Poynting for the Bloodhound SSC.
Fixed Broadband Business Case - Short VersionAndre Fourie
The revenue that can be generated by an LTE base station is influenced by the quality of the signal received by the customer premise equipment (CPE). Most CPE come with omni-directional indoor antennas, but have provision for the connection to external antennas.
Substituting the indoor antennas for directional outdoor antennas has a marked effect on the data transfer speeds of the network. There are two reasons for this. Firstly, outdoor antennas are physically larger than their indoor counterparts and thus have a higher gain. The increase in antenna gain translates directly to an increase in received signal strength. The second advantage is that the outdoor antenna sits in an environment that has much better propagating properties than the indoor antenna. Tests have shown that data speeds 3-5 times faster are possible using external antennas compared to indoor antennas.
It is shown, using a primitive financial model that fairly large financial gains can be made by equipping CPE devices with external antennas. The summary financial effects below are well backed up by real life case studies and theory which interested readers can read in the remainder of this document.
Role antennas play in a MIMO link - paperAndre Fourie
Role antennas play in a MIMO link. Paper presented by Andre Fourie at the Radio Communications Conference.
MIMO, in conjunction with SDMA, is a technology that is used in 4G networks to increase the data throughput of a wireless network. The antennas used in the link have a direct correlation with the performance of a MIMO link. The antenna attributes that play the dominant performance enhancing role in MIMO links are the radiation pattern and the polarization.
The nature of the indoor and outdoor channels is discussed and it is shown that a MIMO link performs far better in outdoor channels; hence the use of outdoor antenna installations is emphasized.
How antenna properties affect MIMO performance? New antenna antenna parameters to understand for selecting/designing effective MIMO (4G/LTE) communications.
Powerful business model for fixed wireless data using outdoor antennas - PaperAndre Fourie
Paper presented at the 2nd Africa Radio Comms Conference in Johannesburg - Nov 2015
By Andre Fourie
The revenue that can be generated by an LTE base station is influenced by the quality of the signal received by the customer premise equipment (CPE). Most CPE come with omni-directional indoor antennas, but have provision for the connection to external antennas.
Substituting the indoor antennas for directional outdoor antennas has a marked effect on the data transfer speeds of the network. There are two reasons for this. Firstly, outdoor antennas are physically larger than their indoor counterparts and thus have a higher gain. The increase in antenna gain translates directly to an increase in received signal strength. The second advantage is that the outdoor antenna sits in an environment that has much better propagating properties than the indoor antenna. Tests have shown that data speeds 3-5 times faster are possible using external antennas compared to indoor antennas.
It is shown, using a primitive financial model that fairly large financial gains can be made by equipping CPE devices with external antennas.
Business case for fixed wireless 4G/LTE using outdoor antennasAndre Fourie
LTE/4G networks business plans involve capex spend on radio access infrastructure to meet business objectives ito customer offerings ito bandwidth, data rates, bulk data and QoS. Assigning some Capex to CPE equipment with outdoor antennas can reduce Capex significantly for same capacity and considerably better reliability and QOS
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
CW RADAR, FMCW RADAR, FMCW ALTIMETER, AND THEIR PARAMETERSveerababupersonal22
It consists of cw radar and fmcw radar ,range measurement,if amplifier and fmcw altimeterThe CW radar operates using continuous wave transmission, while the FMCW radar employs frequency-modulated continuous wave technology. Range measurement is a crucial aspect of radar systems, providing information about the distance to a target. The IF amplifier plays a key role in signal processing, amplifying intermediate frequency signals for further analysis. The FMCW altimeter utilizes frequency-modulated continuous wave technology to accurately measure altitude above a reference point.
HEAP SORT ILLUSTRATED WITH HEAPIFY, BUILD HEAP FOR DYNAMIC ARRAYS.
Heap sort is a comparison-based sorting technique based on Binary Heap data structure. It is similar to the selection sort where we first find the minimum element and place the minimum element at the beginning. Repeat the same process for the remaining elements.
1. Poynting Antennas (Pty) Ltd
5 April 2016 AntennaParameters Part 2 Page 1
ON THE PROPERTIES OF AN ANTENNA
This is part of an internal document that that gives an overview of the properties of
antennas for non-engineers.
We have divided the document into different posts where we discus each of the
parameters:
- Frequency bands, gain and radiation pattern
- Polarisation
- Input Impedance and VSWR
- Port to port Isolation and Cross-polarisation
- Power Handling ability
- Antenna “Specmanship”
Where applicable we have added some videos explaining the properties discussed. You
will find a link to a PDF below.
Introduction
An antenna is a device that converts energy from one form to another. When used in
transmit mode, currents in the coaxial cable (feeding the antenna) flow into the antenna
and the energy is converted to electromagnetic radiation which propagates into space.
When an antenna is used in receive mode, electromagnetic radiation interacts with the
antenna inducing currents into its components. These currents flow along the coaxial
cable connected to the antenna to a receiver.
In some ways the antenna is analogous to a speaker in a sound system. A speaker
converts electrical energy (from the wires powering the speaker) into sound energy which
we can detect using our ears. When operated in the opposite mode a microphone is
created. This device detects sound wave and converts them to electrical energy. An
antenna works with electromagnetic radiation and electric currents rather than sound and
electric currents.
An antenna is described by a number of attributes including frequency bands of
operation, gain, radiation pattern, polarisation, VSWR, input impedance, coupling, power
handling ability and so on.
This document describes each of these parameters.
1. Frequency bands of operation
See part 1
2. Gain and radiation pattern
See part 1
3. Polarisation
The radiation from an antenna comprises both electric and magnetic fields. Once the
radiated wave has established itself – (a distance greater than
2𝐷2
𝜆
from the antenna, where
D is the largest dimension of the antenna and λ is the wavelength), then the electric and
2. Poynting Antennas (Pty) Ltd
5 April 2016 AntennaParameters Part 2 Page 2
magnetic fields are perpendicular to each other (and both are perpendicular to the
direction of propagation – the so called Poynting vector).
Figure 1: Illustrating the plane of the electric field lines (red), magnetic field lines (blue) and
Poynting vector (green)
The polarisation specification for an antenna specifies how the electric field behaves in
the far field (where the radiated wave has established itself).
If the electric field stays in one plane as the wave propagates, then its polarisation is said
to be linear.
Figure 2: Illustrating a linearly polarised wave
On the other hand, if the electric field rotates about the axis of propagation (and does not
change size as it rotates) then the polarisation is said to be circular. Circularly polarised
antennas can be either left or right-hand circularly polarised. The polarisation is defined
as left-hand circularly polarised if the electric fields rotates anti-clockwise about the
direction of propagation.
3. Poynting Antennas (Pty) Ltd
5 April 2016 AntennaParameters Part 2 Page 3
Figure 3: Illustrating a circularly polarised wave
Linear and circular polarisations are the extremes of the polarisation specification and
typically all one will see in a brochure. In reality, however, the polarisation will be
anywhere between these two extremes and the electric field will trace an ellipse as it
rotates about the direction of propagation.
Elliptically polarised waves are typically specified in brochures as circularly polarised,
but they include an additional parameter called the axial ratio. The axial ratio defines the
shape of the ellipse.
Figure 4: Illustrating an elliptically polarised wave
Sometimes the polarisation specification is given as vertical or horizontal. In such cases,
the polarisation is linear and the electric field is vertical/horizontal with respect to the
earth when the antenna is mounted in the correct orientation.
4. Poynting Antennas (Pty) Ltd
5 April 2016 AntennaParameters Part 2 Page 4
When using antennas to form a radio link it is important that the antennas at each end of
the link are correctly oriented. The polarisations should be the same and both have the
same orientation with respect to the earth.
If two linearly polarised antennas are used to form a link and one is mounted vertically
and the other horizontally, then one will experience about a 20 dB drop in the signal
strength (compared to when they are both oriented in the same direction). The same 20
dB reduction in received signal strength will be experience if two circularly polarised
antennas are used with one antenna being left-hand circular and the other right-hand
circular.
If a circularly polarised antenna is used at one end of a link and a linear antenna at the
other end, then the orientation of either antenna will make no difference to the received
signal strength. The signal strength will, however, be 3 dB worse than if one used
antennas of the same polarisation (assuming the gain of the replacement antenna is
unchanged).
Andre Fourie explains polarisation in a video here:
https://youtu.be/1gXNJ5TOmOQ