By completing this presentation will be have a clear idea about Antenna's working principles, Antenna's Types & Antenna's Parameters. At the end to this document you'll have a brief idea about Antenna's Tilt vs Distance Calculation & Cluster wise optimum Antenna Selection procedure. Impact of antenna PIM & VSWR have been described elaborately in this document as well.
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
In radio and electronics, an antenna is an electrical device which converts electric power into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver. In transmission, a radio transmitter supplies an electric current oscillating at radio frequency to the antenna's terminals, and the antenna radiates the energy from the current as electromagnetic waves (radio waves). In reception, an antenna intercepts some of the power of an electromagnetic wave in order to produce a tiny voltage at its terminals, that is applied to a receiver to be amplified.
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.
By completing this presentation will be have a clear idea about Antenna's working principles, Antenna's Types & Antenna's Parameters. At the end to this document you'll have a brief idea about Antenna's Tilt vs Distance Calculation & Cluster wise optimum Antenna Selection procedure. Impact of antenna PIM & VSWR have been described elaborately in this document as well.
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
In radio and electronics, an antenna is an electrical device which converts electric power into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver. In transmission, a radio transmitter supplies an electric current oscillating at radio frequency to the antenna's terminals, and the antenna radiates the energy from the current as electromagnetic waves (radio waves). In reception, an antenna intercepts some of the power of an electromagnetic wave in order to produce a tiny voltage at its terminals, that is applied to a receiver to be amplified.
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.
An Antenna is a transducer, which converts electrical power into electromagnetic waves and vice versa.
An Antenna can be used either as a transmitting antenna or a receiving antenna.
A transmitting antenna is one, which converts electrical signals into electromagnetic waves and radiates them.
A receiving antenna is one, which converts electromagnetic waves from the received beam into electrical signals.
In two-way communication, the same antenna can be used for both transmission and reception.
Basic Parameters
Frequency
Wavelength
Impedance matching
VSWR & reflected power
Bandwidth
Percentage bandwidth
Radiation intensity.
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 type of aerial, widely used with television and VHF radio receivers, consisting of two parallel dipoles connected together at their outer ends and fed at the center of one of them. The length is usually half the operating wavelength.
MicroStrip Antenna
Introduction .
Micro-Strip Antennas Types .
Micro-Strip Antennas Shapes .
Types of Substrates (Dielectric Media) .
Comparison of various types of flat profile printed antennas .
Advantages & DisAdvantages of MSAs .
Applications of MSAs .
Radiation patterns of MSAs .
How to Optimizing the Substrate Properties for Increased Bandwidth ?
Comparing the different feed techniques .
A horn antenna or microwave horn is an antenna that consists of a flaring metal waveguide shaped like a horn to direct radio waves in a beam. Horns are widely used as antennas at UHF and microwave frequencies, above 300 MHz.
An Antenna is a transducer, which converts electrical power into electromagnetic waves and vice versa.
An Antenna can be used either as a transmitting antenna or a receiving antenna.
A transmitting antenna is one, which converts electrical signals into electromagnetic waves and radiates them.
A receiving antenna is one, which converts electromagnetic waves from the received beam into electrical signals.
In two-way communication, the same antenna can be used for both transmission and reception.
Basic Parameters
Frequency
Wavelength
Impedance matching
VSWR & reflected power
Bandwidth
Percentage bandwidth
Radiation intensity.
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 type of aerial, widely used with television and VHF radio receivers, consisting of two parallel dipoles connected together at their outer ends and fed at the center of one of them. The length is usually half the operating wavelength.
MicroStrip Antenna
Introduction .
Micro-Strip Antennas Types .
Micro-Strip Antennas Shapes .
Types of Substrates (Dielectric Media) .
Comparison of various types of flat profile printed antennas .
Advantages & DisAdvantages of MSAs .
Applications of MSAs .
Radiation patterns of MSAs .
How to Optimizing the Substrate Properties for Increased Bandwidth ?
Comparing the different feed techniques .
A horn antenna or microwave horn is an antenna that consists of a flaring metal waveguide shaped like a horn to direct radio waves in a beam. Horns are widely used as antennas at UHF and microwave frequencies, above 300 MHz.
Frequency-independent (FI) antennas are radiating structures capable of maintaining consistent impedance and pattern characteristics over multiple-decade bandwidths. Their finite size limits the lowest frequency of operation, and the finite precision of the center region bounds the highest frequency of operation.
Tutorial Content
This tutorial provides a broad-based discussion of radar system, covering the following topics:
-Introduction to Radars in Military and Commercial Applications
-Radar System Block Diagram
-Radar Antennas (slotted waveguide array, planar array), Transmitter (magnetron, solid-state), Receiver, Pedestal and Radome
-Plot Extraction, Tracking Algorithms and Display
-Radar Range Equation, Detection Performance
-Wave Propagation and Radar Cross Section
-Emerging and Advanced Radar Systems (phased-array, multi-beam, multi-mode, FMCW, solid-state)
In the discussion, practical systems, technical specifications and data will be used to enhance learning.In addition, simulation results will also be used to present findings.
The objective of the tutorial session is to equip participants with solid understanding of radar systems for system level applications and prepare them for advanced and professional radar courses, projects and research.
This tutorial is designed and developed based on the following references:
[1] G. W. Stimson, Introduction to Airborne Radar Second Edition, Scitech Publishing, 1998.
[2] L. V. Blake, A Guide to Basic Pulse-Radar Maximum-Range Calculation, NRL Report 6930, 1969.
[3] K. H. Lee, Radar Systems for Nanyang Technological University, TBSS, 2014.
Kerala Engineering Architecture Medical is an entrance examination series for admissions to various professional degree courses in the state of Kerala, India. It is conducted by the Office of the Commissioner of Entrance Exams run by the Government of Kerala
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The ways in which an element—or compound such as water—moves between its various living and nonliving forms and locations in the biosphere is called a biogeochemical cycle. Biogeochemical cycles important to living organisms include the water, carbon, nitrogen, phosphorus, and sulfur cycles.
The AC and DC bridge both are used for measuring the unknown parameter of the circuit. The AC bridge measures the unknown impedance of the circuit. The DC bridge measures the unknown resistance of the circuit.
The Wien bridge is a type of bridge circuit that was developed by Max Wien in 1891. The bridge consists of four resistors and two capacitors. At the time of the Wien bridge's invention, bridge circuits were a common way of measuring component values by comparing them to known values.
For most of us, our name existed even before we did.
In anticipation of our arrival, our parents went through an ultra stressful process of narrowing down dozens of potential names until they chose the perfect one.
Luckily they did, because whatever your name is, it has followed you throughout your entire life; and in some cases, people may have heard of your name before they’ve ever met you.
When it comes to how to name an app, it’s of similar importance as naming a child. The name of your app will follow your brand forever, and in many cases, potential users will hear the name before they ever actually use your app.
flora and fauna of himachal pradesh and keralaAJAL A J
flora and fauna of himachal pradesh and kerala
A green pearl in the Himalayan crown, Himachal Pradesh is blessed with a rich flora and fauna that graces the land with grandeur and majesty. Other animals that can be sighted in the wild include the ibex, wild yak, ghoral deer, musk deer, Himalayan black bear, brown bear, leopards and the Himalayan Thar. Also kerala is gods on country
Bachelor of Science in Cardio-vascular technology is an undergraduate course in cardiology. These technologists assist the physicians in the diagnosis and the treatment of cardiac (heart) and peripheral vascular conditions (blood vessels). The cardiovascular technologists are also responsible for preparing the patients for open-heart surgeries and pacemaker implantation surgeries. The technologists also monitor the patient’s cardiac parameters while they undergo the surgery. B. Sc. in Cardiovascular technology is a three years’ full-time undergraduate course and is an interesting and important course in medicine.
`Remove Unprofitable Products and Services. The products or services with the highest gross profit margin are the most important to your business. ...
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Then, you’re halfway there. Being an NRI, your top preference would be IITs and NITs of India. If that's the case, you must know the fee structure of both the IITs, NITs (under DASA scheme), Centrally Funded Institutions and State-Level Govt. Engineering Colleges.
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Subjects to study if you want to work for a charityAJAL A J
The charity sector can be competitive and experience, volunteer or otherwise, can count for a lot. But there are ways to make that third sector CV stand out from the competition. Why not take some courses? A course can be a great way to make your application shine and an opportunity to learn new skills and ideas.
Joint Entrance Examination - Main or commonly known as JEE Main is a national level entrance exam conducted by the NTA to offer admission to BE/BTech, BPlan and BArch courses at the IIITs (Indian Institute of Information Technology), NITs (National Institute of Technology) and other Centrally Funded Technical Institutions (CFTIs) across the country.
Enterprise Excellence is Inclusive Excellence.pdfKaiNexus
Enterprise excellence and inclusive excellence are closely linked, and real-world challenges have shown that both are essential to the success of any organization. To achieve enterprise excellence, organizations must focus on improving their operations and processes while creating an inclusive environment that engages everyone. In this interactive session, the facilitator will highlight commonly established business practices and how they limit our ability to engage everyone every day. More importantly, though, participants will likely gain increased awareness of what we can do differently to maximize enterprise excellence through deliberate inclusion.
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What are the main advantages of using HR recruiter services.pdfHumanResourceDimensi1
HR recruiter services offer top talents to companies according to their specific needs. They handle all recruitment tasks from job posting to onboarding and help companies concentrate on their business growth. With their expertise and years of experience, they streamline the hiring process and save time and resources for the company.
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𝐓𝐉 𝐂𝐨𝐦𝐬 (𝐓𝐉 𝐂𝐨𝐦𝐦𝐮𝐧𝐢𝐜𝐚𝐭𝐢𝐨𝐧𝐬) is a professional event agency that includes experts in the event-organizing market in Vietnam, Korea, and ASEAN countries. We provide unlimited types of events from Music concerts, Fan meetings, and Culture festivals to Corporate events, Internal company events, Golf tournaments, MICE events, and Exhibitions.
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2. Antennas come in a wide variety of sizes and shapes
Antenna types
Helical antenna
Horn antenna
Parabolic reflector antenna
3. Propagation mode adapter
During both transmission and receive operations
the antenna must provide the transition between
these two propagation modes.
4. Implementation
Antenna arrays
Antenna array composed of several similar radiating
elements (e.g., dipoles or horns).
Element spacing and the relative amplitudes and phases
of the element excitation determine the array’s radiative
properties.
Linear array examples
Two-dimensional array of
microstrip patch antennas
5. ANTENNA ARRAYS
• Antenna arrays is group of antennas or antenna
elements arranged to provide desired directional
characteristics.
• Generally any combination of elements can form an
array.
• However equal elements of regualar geometry are
usually used.
7. YAGI-UDA ANTENNA
• It is a directional antenna consisting of a driven
element (typically a dipole or folded dipole) and
additional parasitic elements (usually a so-called
reflector and one or more directors).
• All the elements are arranged collinearly and close
together.
• The reflector element is slightly longer (typically 5%
longer) than the driven dipole, whereas the so-called
directors are a little bit shorter.
• The design achieves a very substantial increase in the
antenna's directionality and gain compared to a
simple dipole.
8.
9. ANTENNA ARRAYS
It is often impossible to generate a desired
antenna pattern with just one antenna
Using two or more antenna elements provides
the designer with more design variables e.g.
1. Number of elements
2. Physical arrangement of elements
3. Amplitude and Phase of input signals
14. FOLDED DIPOLE
• Folded antenna is a single antenna
but it consists of two elements.
• First element is fed directly while
second one is coupled inductively at
its end.
• Radiation pattern of folded dipole is
same as that of dipole antenna i.e
figure of eight (8).
16. HERTZ ANTENNA
• The Hertzian dipole is a theoretical short
dipole (significantly smaller than the
wavelength) with a uniform current along its
length.
• A true Hertzian dipole cannot physically
exist, since the assumed current distribution
implies an infinite charge density at its ends,
and significant radiation requires a very high
current over its very short length.
17.
18. LOOP ANTENNA
• Radiation pattern of loop
antenna is a doughnut
pattern.
• Can be circular or square
loop
• No radiation is received
normal to the plane of loop
and null is obtained in this
direction.
• Application:
Used
for
direction finding applications
19. TURNSTILE ANTENNA
• A turnstile antenna is a set of two
dipole antennas aligned at right
angles to each other and fed 90
degrees out-of-phase.
• The name reflects that the antenna
looks like a turnstile when mounted
horizontally.
• When mounted horizontally the
antenna is nearly omnidirectional on
the horizontal plane.
20. Antenna arrays
• Consist of multiple (usually identical) antennas (elements)
‘collaborating’ to synthesize radiation characteristics not
available with a single antenna. They are able
– to match the radiation pattern to the desired coverage area
– to change the radiation pattern electronically (electronic scanning)
through the control of the phase and the amplitude of the signal
fed to each element
– to adapt to changing signal conditions
– to increase transmission capacity by better use of the radio
resources and reducing interference
• Complex & costly
– Intensive research related to military, space, etc. activities
» Smart antennas, signal-processing antennas, tracking antennas,
phased arrays, etc.
Source: adapted from N Gregorieva
22. Owens Valley Radio Observatory
The Earth’s
atmosphere is
transparent in
the narrow
visible-light
window
(4000-7000
angstroms) and
the radio band
between 1 mm
and 10 m.
[Sky & Telescope
Feb 1997 p.26]
23. The New Mexico Very Large Array
[Sky & Telescope
Feb 1997 p. 30]
27 antennas along 3 railroad tracks provide baselines up to 35 km. Radio
images are formed by correlating the signals garnered by each antenna.
25. 2 GHz adaptive antenna
• A set of 48
2GHz
antennas
– Source:
Arraycomm
26. Phased Arrays
• Array of N antennas in a linear or twodimensional configuration + beam-forming
& control device
• The amplitude and phase excitation of each
individual antenna controlled electronically
(“software-defined”)
– Diode phase shifters
– Ferrite phase shifters
• Inertia-less beam-forming and scanning (µsec)
with fixed physical structure
32. • Switched beam antennas
– Based on switching function between
separate directive antennas or predefined
beams of an array
• Space Division Multiple Access
(SDMA) = allocating an angle
direction sector to each user
– In a TDMA system, two users will be
allocated to the same time slot and the
same carrier frequency
– They will be differentiated by different
direction angles
33. • Dynamically phased array
(PA):
– A generalization of the
switched lobe concept
– The radiation pattern
continuously track the
designated signal (user)
– Include a direction of arrival
(DoA) tracking algorithm
35. Beamformers vs. omnidirectional antennas
2) Beamformers can reject interference while omnidirectional
antennas can’t: Improve SNR and system capacity!
interference
user
null
interference
user
3) Beamformers directionally send down link information to the
users while omnidirectional antennas can’t: save energy!
36. Beam Steering
Beam direction
θ
d
3∆
2∆
∆
• BeamEqui-phase
steering
wave front
using
phase
∆ = [(2π/λ)d sinθ]
shifters at
Radiating
each
elements
radiating
Phase
0
shifters
element
Power
distribution
37. Beamforming antennas in ad hoc networks
Z0=50Ω,L≈λ/2 Z0=25Ω,L≈λ/2
Z0=50Ω
Series resonant patch array
interference
Phased patch
antenna
target
Phased patch array
40. 4-Bit Phase-Shifter (Example)
Input
Bit #3
Bit #4
0 or 22.5
0
0
0 or 45
0
Bit #1
Bit #2
0
0 or 90
0
0
0 or 180
0
Steering/ Beam-forming Circuitry
Alternative solution: Transmission line with controlled delay
0
Output
44. Adaptive (“Intelligent”)Antennas
• Array of N antennas in a linear,
circular, or planar configuration
• Used for selection signals from
desired sources and suppress incident
signals from undesired sources
• The antenna pattern track the sources
• It is then adjusted to null out the
interferers and to maximize the signal
to interference ratio (SIR)
• Able to receive and combine
constructively multipath signals
45. Smart antenna systems
Military
networks
switched array
adaptive array
Cellular
communication
networks
switched array
adaptive array
3G Data rate:100kbps
Wireless
local area
networks
switched array
adaptive array
Wi-Fi Data rate:11Mbps
46. Smart antenna systems
top view(horizontal)
5
4
6
3
7
2
interference
8
1
9
16
10
15
11
12
13
14
Switched array (predetermined)
user
47. Smart antenna systems
top view(horizontal)
Interference 1
user 1
user 2
Interference 2
Adaptive array
48. • The amplitude/ phase
excitation of each antenna
controlled electronically
(“software-defined”)
• The weight-determining
algorithm uses a-priori
and/ or measured
information to adapt
antenna to changing
environment
• The weight and summing
circuits can operate at the
RF and/ or at an
intermediate frequency
1
w1
Σ
wN
N
Weight-determining
algorithm
49. Antenna sitting
• Radio horizon
• Effects of obstacles & structures nearby
• Safety
– operating procedures
– Grounding
• lightning strikes
• static charges
– Surge protection
• lightning searches for a second path to ground
50. Antenna Arrays: Benefits
• Possibilities to control electronically
–
–
–
–
–
Direction of maximum radiation
Directions (positions) of nulls
Beam-width
Directivity
Levels of sidelobes
using standard antennas (or antenna collections)
independently of their radiation patterns
• Antenna elements can be distributed along straight
lines, arcs, squares, circles, etc.
51. Array Blindness
•
Direct consequence of mutual coupling
•
Can result in complete cancellation of the
radiated beam at some scan angle
•
Occurs when most of the central elements of
the array have reflection coefficients close to
unity
52. Terminology
Antenna – structure or device used to collect or radiate electromagnetic waves
Array – assembly of antenna elements with dimensions, spacing, and illumination sequency such that the
fields of the individual elements combine to produce a maximum intensity in a particular direction and
minimum intensities in other directions
Beamwidth – the angle between the half-power (3-dB) points of the main lobe, when referenced to the peak
effective radiated power of the main lobe
Directivity – the ratio of the radiation intensity in a given direction from the antenna to the radiation intensity
averaged over all directions
Effective area – the functional equivalent area from which an antenna directed toward the source of the
received signal gathers or absorbs the energy of an incident electromagnetic wave
Efficiency – ratio of the total radiated power to the total input power
Far field – region where wavefront is considered planar
Gain – ratio of the power at the input of a loss-free isotropic antenna to the power supplied to the input of the
given antenna to produce, in a given direction, the same field strength at the same distance
Isotropic – radiates equally in all directions
Main lobe – the lobe containing the maximum power
Null – a zone in which the effective radiated power is at a minimum relative to the maximum effective radiation
power of the main lobe
Radiation pattern – variation of the field intensity of an antenna as an angular function with respect to the axis
Radiation resistance – resistance that, if inserted in place of the antenna, would consume that same amount
of power that is radiated by the antenna
Side lobe – a lobe in any direction other than the main lobe
Editor's Notes
In this example, the RF power is evenly distributed through the phase shifters, amplifiers and radiating elements. All phase shifters are in phase. The resulting wave fronts propagate directly to the right.
In this sequence of images, there is a constant phase difference between neighboring phase shifters. Consequently, the direction of the waves is slightly downward. This illustrates how phased-array antennas can redirect beams.