Fundamentals Of Applied Electromagnetics
7th Edition
ISBN: 9781292082448
Author: Fawwaz T Ulaby Umberto Ravaioli
Publisher: Pearson Education Dorling Kindersley
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 9, Problem 2P
A 50 cm long center-fed dipole directed along the z direction and located at the origin is excited by a 1 MHz source. If the current amplitude is I0 = 10 A, determine:
- (a) The power density radiated at 2 km along the broadside of the antenna pattern.
- (b) The fraction of the total power radiated within the sector between θ = 85° and θ = 95°?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Q. Calculate the radiation resistance of a short dipole (with a triangular current distribution) of length 0.3 m operating at 100 MHz. If the total resistance of the antenna is 2.2 Ω, calculate the maximum effective area and the radiation efficiency of the dipole. Calculate the open circuit voltage induced at the terminals of the dipole if it is oriented along the z - direction and the incident electric field at the dipole is Ei = (ax 4 + ay 3 + az 5) V/m.
An electric field strength of 10 µV/m is to be measured at an observation point θ = π/2, 500 km from a half-wave dipole antenna operating in air at 50 MHz.
(a) What is the length of the dipole
(b) Calculate the current that must be fed to the antenna
(c) Find the average power radiated by the antenna
(d) If a transmission line with Z0 = 75 ohm is connected to the antenna, determine the Γ and SWR.
An isotropic antenna is radiating evenly in the r–direction in free space. The totalelectric field (E0) is 20 V/m at 1-m distance. Determine the following parameters at adistance of 139 m from the antenna,
(ii) The radiation power density.
Chapter 9 Solutions
Fundamentals Of Applied Electromagnetics
Ch. 9.1 - What does it mean to say that most antennas are...Ch. 9.1 - What is the radiated wave like in the far-field...Ch. 9.1 - In a Hertzian dipole, what is the underlying...Ch. 9.1 - Outline the basic steps used to relate the current...Ch. 9.1 - A 1 m long dipole is excited by a 5 MHz current...Ch. 9.2 - Prob. 5CQCh. 9.2 - What is the magnitude of the directivity of an...Ch. 9.2 - An antenna has a conical radiation pattern with a...Ch. 9.2 - Prob. 3ECh. 9.3 - What is the physical length of a half-wave dipole...
Ch. 9.3 - How does the radiation pattern of a half-wave...Ch. 9.3 - How does the radiation efficiency of a...Ch. 9.3 - Prob. 4ECh. 9.3 - Prob. 5ECh. 9.5 - Prob. 6ECh. 9.5 - At 100 MHz, the pattern solid angle of an antenna...Ch. 9.6 - If the operating frequency of the communication...Ch. 9.6 - Prob. 9ECh. 9.6 - Prob. 10ECh. 9.8 - Verify that Eq. (9.86) is a solution of Eq. (9.85)...Ch. 9.8 - Prob. 12ECh. 9.8 - What condition must be satisfied in order to use...Ch. 9.8 - Derive an expression for the array factor of a...Ch. 9.8 - Prob. 15ECh. 9.11 - Prob. 11CQCh. 9.11 - Prob. 12CQCh. 9.11 - Prob. 13CQCh. 9.11 - Prob. 14CQCh. 9.11 - Prob. 15CQCh. 9 - A center-fed Hertzian dipole is excited by a...Ch. 9 - A 50 cm long center-fed dipole directed along the...Ch. 9 - Prob. 3PCh. 9 - Determine the following: (a) The direction of...Ch. 9 - Repeat Problem 9.4 for an antenna with...Ch. 9 - A 2 m long center-fed dipole antenna operates in...Ch. 9 - Repeat Problem 9.6 for a 20 cm long antenna...Ch. 9 - Prob. 9PCh. 9 - An antenna with a radiation efficiency of 90% has...Ch. 9 - Prob. 11PCh. 9 - The normalized radiation intensity of a certain...Ch. 9 - Repeat Problem 9.6 for a 1 m long half-wave dipole...Ch. 9 - Prob. 14PCh. 9 - A 50 cm long dipole is excited by a sinusoidally...Ch. 9 - Prob. 16PCh. 9 - For a dipole antenna of length l = 3/2, (a)...Ch. 9 - Prob. 18PCh. 9 - Prob. 19PCh. 9 - Prob. 20PCh. 9 - A car antenna is a vertical monopole over a...Ch. 9 - Determine the effective area of a half-wave dipole...Ch. 9 - A 3 GHz line-of-sight microwave communication link...Ch. 9 - A half-wave dipole TV broadcast antenna transmits...Ch. 9 - A 150 MHz communication link consists of two...Ch. 9 - Consider the communication system shown in Fig....Ch. 9 - The configuration shown in Fig. P9.27 depicts two...Ch. 9 - Prob. 28PCh. 9 - The configuration shown in Fig. P9.29 depicts a...Ch. 9 - Prob. 30PCh. 9 - Prob. 31PCh. 9 - A uniformly illuminated rectangular aperture...Ch. 9 - An antenna with a circular aperture has a circular...Ch. 9 - Prob. 34PCh. 9 - Prob. 35PCh. 9 - Prob. 36PCh. 9 - Prob. 37PCh. 9 - Prob. 38PCh. 9 - Prob. 39PCh. 9 - Prob. 40PCh. 9 - Find and plot the normalized array factor and...Ch. 9 - Prob. 44PCh. 9 - A three-element linear array of isotropic sources...Ch. 9 - An eight-element linear array with /2 spacing is...Ch. 9 - A linear array arranged along the z axis consists...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, electrical-engineering and related others by exploring similar questions and additional content below.Similar questions
- A horizontal infinitesimal electric dipole of constant current I0 is placed symmetrically about the origin and directed along the x-axis. Derive the(a) far-zone fields radiated by the dipole(b) directivity of the antennaarrow_forwardThe radial component of the radiated power density of an infinitesimal linear dipole of length is given by Wav=ar Wr =arAmsin2(theta)/r2 W/m2 Where Am = Peak value of power density; theta = usual spherical co-ordinate and ar = radial unit vector. Calculate the directivity of the antenna.arrow_forwardA centre fed linear dipole antenna, three and half wavelength long, has a feed current of 15 A RMS. Calculate the rms electric field at seven wavelength away from the antenna.arrow_forward
- What will be the free space path loss if the distance between the two isotropic antenna is 2.5 km and the radiating frequency is 32.85 MHz? Show detailed calculation please.arrow_forward) Calculate the radiation resistance of a single turn and an 8-turns loop antenna. The loop of radius λ/25 and the medium is free space.arrow_forwardA screen, having a Screening Effectiveness (S) of 31.62 at 100 MHz, is located 5 m from a 2 cm radius conductor loop that carries a signal current of 7.5 mA at a frequency of 100 MHz. Determine the maximum electric field strength transmittedthrough the screen (Et, µVm-1) resulting from radiated emissions emanating from the conductor loop.arrow_forward
- An antenna radiates a total power of 100W in the direction of maximum radiation, the field strength at a distance of 10Km was found to be 12mV/m. What is the gain of the antenna? Assume free space propagation. If η=90% find directivity.arrow_forwardA 0.48520λ0 dipole antenna is made to work at 4 GHz. The antenna is then connected to a 12 V voltage source which has an internal resistance of 25 Ω) a) Make a diagram of the above system, b) Is an impedance matching circuit needed? If yes, where should the impedance circuit be inserted and make a diagram of the system with the adjusting circuit, c) How many cm is the length of the dipole antenna above, Solve Subparts A,B,C in 25 minutes ASAParrow_forwardA C-band radar with an antenna 1.8m in radius transmits 60kw at 6 GHz. If the minimum detectable power is 0.5mw, for a target cross-section of 5msq, Calculate the maximum range in meters Assume the effective area of the antenna is 80% of the actual area.arrow_forward
- The normalized radiation intensity of a given antenna is given by(a) U = sin θ sin φ (b) U = sin θ sin2 φ(c) U = sin θ sin3 φ (d) U = sin2 θ sin φ(e) U = sin2 θ sin2 φ (f) U = sin2 θ sin3 φThe intensity exists only in the 0 ≤ θ ≤ π, 0 ≤ φ ≤ π region, and it is zeroelsewhere. Find the(a) exact directivity (dimensionless and in dB).(b) azimuthal and elevation plane half-power beamwidths (in degreearrow_forwardThe radiation resistance of a dipole antenna is 359 ohms and the antenna is operating at a wavelength of 0.05 meters. What will be the effective length of this dipole antenna? Whatarrow_forwardCalculate the radiation resistance of a lambda/10 wire dipole in free space.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Introductory Circuit Analysis (13th Edition)Electrical EngineeringISBN:9780133923605Author:Robert L. BoylestadPublisher:PEARSONDelmar's Standard Textbook Of ElectricityElectrical EngineeringISBN:9781337900348Author:Stephen L. HermanPublisher:Cengage LearningProgrammable Logic ControllersElectrical EngineeringISBN:9780073373843Author:Frank D. PetruzellaPublisher:McGraw-Hill Education
- Fundamentals of Electric CircuitsElectrical EngineeringISBN:9780078028229Author:Charles K Alexander, Matthew SadikuPublisher:McGraw-Hill EducationElectric Circuits. (11th Edition)Electrical EngineeringISBN:9780134746968Author:James W. Nilsson, Susan RiedelPublisher:PEARSONEngineering ElectromagneticsElectrical EngineeringISBN:9780078028151Author:Hayt, William H. (william Hart), Jr, BUCK, John A.Publisher:Mcgraw-hill Education,
Introductory Circuit Analysis (13th Edition)
Electrical Engineering
ISBN:9780133923605
Author:Robert L. Boylestad
Publisher:PEARSON
Delmar's Standard Textbook Of Electricity
Electrical Engineering
ISBN:9781337900348
Author:Stephen L. Herman
Publisher:Cengage Learning
Programmable Logic Controllers
Electrical Engineering
ISBN:9780073373843
Author:Frank D. Petruzella
Publisher:McGraw-Hill Education
Fundamentals of Electric Circuits
Electrical Engineering
ISBN:9780078028229
Author:Charles K Alexander, Matthew Sadiku
Publisher:McGraw-Hill Education
Electric Circuits. (11th Edition)
Electrical Engineering
ISBN:9780134746968
Author:James W. Nilsson, Susan Riedel
Publisher:PEARSON
Engineering Electromagnetics
Electrical Engineering
ISBN:9780078028151
Author:Hayt, William H. (william Hart), Jr, BUCK, John A.
Publisher:Mcgraw-hill Education,
How does an Antenna work? | ICT #4; Author: Lesics;https://www.youtube.com/watch?v=ZaXm6wau-jc;License: Standard Youtube License