ICT Role in 21st Century Education & its Challenges.pptx
2006-1 중간고사문제(안테나공학)
1. 2006 mid-term examination (110)
Antenna Engineering
Date: October 26, 2006.
1. Calculate the following parameters of a Hertzian dipole antenna with
I = 700 [mA] , ∆z = 0.3 [mm] , f = 13 [GHz]. (90)
1)E-field [V/m] and H-field [A/m] at
r = 13 [m] , θ = 50 , φ = 90 (20)
2)Radiation power [dBm] and resistance [ Ω ] (20) Hint:) dBm =
10log10 ( P / 1 [mW ])
2π
3)Input impedance and equivalent circuit with
Z 0 = 75 [Ω] , β = k =
λ (30)
j
Hint:) Z open = − R
ωC , = radiation resistance
4)Draw the input impedance point for 3) on the Smith chart. (10)
5)Compare a Hertzian dipole antenna and a half-wave dipole antenna in terms
of a resonance. (10)
2. Explain how an antenna radiates an electromagnetic wave in terms of a current
density J , a vector potential A . Do not use any formula in the textbook. (20)
![2006 mid-term examination (110)
Antenna Engineering
Date: October 26, 2006.
1. Calculate the following parameters of a Hertzian dipole antenna with
I = 700 [mA] , ∆z = 0.3 [mm] , f = 13 [GHz]. (90)
1)E-field [V/m] and H-field [A/m] at
r = 13 [m] , θ = 50 , φ = 90 (20)
2)Radiation power [dBm] and resistance [ Ω ] (20) Hint:) dBm =
10log10 ( P / 1 [mW ])
2π
3)Input impedance and equivalent circuit with
Z 0 = 75 [Ω] , β = k =
λ (30)
j
Hint:) Z open = − R
ωC , = radiation resistance
4)Draw the input impedance point for 3) on the Smith chart. (10)
5)Compare a Hertzian dipole antenna and a half-wave dipole antenna in terms
of a resonance. (10)
2. Explain how an antenna radiates an electromagnetic wave in terms of a current
density J , a vector potential A . Do not use any formula in the textbook. (20)](https://image.slidesharecdn.com/testantenna2006-1-120422015727-phpapp02/85/2006-1-1-320.jpg)
