RF components

RF_Passive 2Polarization States for Plane Wave

Tony Fang, NTU 2003

10-1

Planar Electromagnetic Wave (8) ° Poynting Theorem (a) í (E×H)(-ds)=/t[ì (1/2)εE2dν]+ /t[ì (1/2)H2dν] + ì σ E2dν

(b) P(R,t)=E(R,t)×H(R,t) (w/m2) Pav(R)=(1/2)Re{E(R)×H*(R)} (w/m2) (c) We= (1/2)εE2 Wm= (1/2)H2 Pσ= σ E2
Tony Fang, NTU 2003

(J/m3) (J/m3) (w/m3)
10-2

What Is An Antenna ?

Tony Fang, NTU 2003

10-3

Basic Antenna Theory (1) ° Maxwell’s equations ×E = -B/t ×H = J + D/t D = ρν B = 0 ° Potential functions B = ×A E = -V- A/t
Tony Fang, NTU 2003 10-4

where D = εE B = H

Necessary Conditions for Radiation

Tony Fang, NTU 2003

10-5

Basic Antenna Theory (2) ° Nonhomogeneous wave equation (a) eqs. 2A - ε(2A/t2) = -J 2V - ε(2V/t2) = -ρ/ε (b) sol. A = (/4π)∫ν’(Je-jkR/R)dν’ V = (1/4πε)∫ν’(ρe-jkR/R)dν’

°

Steps of sol