April 26, 2006 Problem 1.5 A hypothetical isotropic antenna is radiating in free space. At a...
Solve the following: a. Compare the current required to radiate 10W from a Hertzian dipole of length 0.12 and a current loop of radius 0.12. b. An isotropic antenna is radiating in free space. At a distance of 100m the antenna the field measured is 1V/m. i) Find the power density at this location; ii) Determine the total power radiated by the antenna
Problem 1.4 An aperture antenna is radiating in free space. The dimensions of the aperture are a = 7.112 mm and b = 3.556 mm. a) What are the three field regions of this antenna? b) Determine the boundaries of these regions. 1/3
9. (6 points) An antenna engineer is asked to design a X/2 dipole antenna to operate at 450 MHz. (a) Calculate the length of the antenna if it is located in free space. (b) Calculate the magnetic field intensity, H, at a distance of 400km, polar position 0 = 30 degrees and current I = 2A (c) What value of the current I is needed for the total radiated power to equal 100 mW. (d) Determine the length of the...
Can someone please explain how to solve the problem below? 1. (10) A Hertzian dipole antenna has a length of 5 mm and carries 100 MHz current of 2 Amps. Find the (a) magnitude of the E and H fields 1000 m away from the antenna at an angle = 30° and the radiated power, (b) Prad.
Please show step to answer problem below A half-wave dipole is radiating into free-space. The coordinate system is defined so that the origin is a the center of the dipole and the z-axis is aligned with the dipole input power to the dipoles 92 w. Assuming an overall efficiency of 40%, find the power density (in W/m2 at r 507 m, = 61, ? =0
11.12 The amplitude of the electric field intensity of a half-wave dipole antenna at r 5 km and /6rad is 0.01 V/m in free space. If the operating frequency is 30 MHz, determine its length and the total power that it radiates. Alse, write express 11.12 The amplitude of the electric field intensity of a half-wave dipole antenna at r 5 km and /6rad is 0.01 V/m in free space. If the operating frequency is 30 MHz, determine its length...
8. (6 points) A Hertzian dipole antenna in free space has /= 0.02. The following are in far-field: (a) What value of current I is necessary to radiate a total power of 60 mW? (b) What is the ratio of the magnetic field intensity, H, at the polar angles 0 = 10 degrees and 80 degrees (c) What fraction of the total radiated power is contained in the region 0 < 60 degrees (d) What is the radiation resistance, Rrad?...
Question 1 The power radiated by a lossless antenna is 10 watts. The directional characteristics of the antenna are represented by the radiation intensity of U = 2cos3θ watts/unit solid angle. Find the (a) Maximum power density at a distance of 1000 m (assume far-field distance) (b) Maximum directivity (c) Maximum gain Question 2 In target-search ground-mapping radars it is desirable to have echo power received from a target, of constant cross section, to be independent ofits range. For one such application, the desirable radiation intensity...
A plane wave is propagating in free space in the +z direction. The magnitude of the electric field intensity is 120 V/m. Both electric and magnetic fields are in phase. Determine the average power density in Watt per square meter.
9. The electric field of a wave is E = 100 cos(26 x 108t -- 3y)Ê V/m. Find (a) the relative permittivity of the medium, and (b) the wavelength. 10. In Spherical coordinates the spherical wave E =(100/r) (sin cos(at - Br)) , H =(0.265/r) (sin cos(at - Br)) • represents the electromagnetic field at large distances, r, from a certain dipole antenna an emitter) in free space. Find the average power crossing the hemispherical shell r = 1 km,...