SOLVED Numerical's - Antenna Theory - Page 6.


16) Sketch the normalized E-field and H-field patterns for
a. A half-wave dipole
b. A quarter-wave monopole.
SOLUTION:

a)



b) The same as for λ/2 dipole except that the fields are zero for θ > π/2 as shown:





17) In free space, an antenna has a far zone field given by





Determine the radiated power?
SOLUTION:








































18) At the far field, the electric field produced by antenna is






Sketch the vertical pattern of the antenna. Your plot should include as many points as possible.
SOLUTION:


       f(θ) = | cosθ cosφ |

            For the vertical pattern, φ = 0 which means,

                       f(θ) = | cosθ | which is sketched below






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