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Kingdom of Saudi Arabia Ministry of Higher Education Majmaah University College of Engineering Department: Electrical Engineering Exam Information Course code: Instructor: Section number: Exam time: Exam hall: Number of pages: First Exam EE 435 Course Title: Antenna and wave propagation Dr Yazeed Qasaymeh Exam date: 10 November 2014 From: 10:00 am To: 12:00 pm 3D038 4 Total score: 20 points Student’s Information Name: ID: Exam Instructions: Read the questions carefully and several times. Writing clearly will make it possible to assess your answers correctly. Any form of cheating, intention to cheating, or disruption of the exam will subject you to a disciplinary action as specified by the university’s regulations. Carrying or using the mobile phone during the exam is not allowed. Using the phone during the exam will carry a disciplinary action. The calculator is only permitted by the exam supervisor. No student can leave the exam room during the first half hour of the exam. Any student coming after the first half hour of the exam will not be permitted to enter the exam. A student leaving the exam, even for legitimate reasons, may not be given a makeup exam. Points Earned: Question 1 2 3 4 Score Total score in the exam: Dear student, we encourage you to answer the exam the best you can and we wish you all success. Q1) Locate the pattern parameters in the following normalized antenna power pattern (5PTS) Q2) the radial component of the radiated power density of an antenna is given by W rad W r .ar Ao Where sin( ) .ar r2 Ao is the peak value of the power density. is the usual spherical coordinate. ar is the radial unit vector. a) Determine the total radiated power. (2PTS) b) Write an expression of the directivity as a function of the directional angels and (3PTS) Q3) the radial component of the radiated power density of an infinitesimal dipole of length L is given by: W rad Where sin 2 ( ) W r .ar Ao .ar r2 Ao is the peak value of the power density. is the usual spherical coordinate. ar is the radial unit vector. a) Determine the maximum value directivity of the antenna (3PTS) b) Express the directivity as a function of the directional angles and (2PTS) Q4) a lossless resonant half-wave dipole antenna with input impedance of 73 Ohm is to be connected to a transmission line whose characteristics impedance is 50 Ohm assuming that the pattern of the antenna is given approximately by U B 0 sin 3 ( ) Find the overall maximum gain of the antenna. (5PTS)