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課程名稱︰天線
課程性質︰選修
課程教師︰許博文
開課學院：電資學院
開課系所︰電信所
考試日期（年月日）︰2009/1/15
考試時限（分鐘）：120
是否需發放獎勵金：是
（如未明確表示，則不予發放）
試題 :
Final Examination:
1.Antennas 1 to 4 are similar and similarly oriented and located at the points
(d,0),(-d,0),(0,d),and(0,-d) in the xy-plane. Neighboring antennas are excited
in opposite phase with currents of the same magnitude. For d=3λ/8, find and
sketch the absolute value of the array factor. (20%)
2.Solve problem 5.10 in Chapter 5 of Elliott's Book. (15%)
3.Moment Method can be used to solve not only the integral equations but also
the differential equations. Use Galerkin's Moment Method to find the best (or
exact) solution of the following differential equation. ( i.e.:f(x)=? )
-d^2f/dx^2 = 1+4x^2 where f(0) = f(1) = 0
[Hint:f_n = x-x^(n+1)] (15%)
Final Examination Take home :
1.Use Taylor Synthesis of Sum Patterns, plot the current amplitude
distribution and the array pattern for a 41-element array with half-wavelength
spacing. n_bar = 5. and SLL = -25dB.
2.Use the method of moments and pulse functions spread over 10 equal intervals
to find the current distribution on a slender center-fed cylinderical dipole
for a/λ = 0.01 and 2l/λ = 0.45(0.02)0.55. Tabulate the input impedance versus
dipole length. Also, repeat this problem but use four sinusoidal function.
Due Date : 2009/1/15
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