Electromagnetic Waves and Antennas combined - Chapter 14 ppt

... + ˆ θ θ θ cos θ (14. 8.2) 594 14. Radiation Fields Fig. 14. 8.1 Cartesian, cylindrical, and spherical coordinates. Fig. 14. 8.2 Spherical coordinates viewed from xy-plane and zρ-plane. The relationships ... linspace(0,pi,Nth)); 14 Radiation Fields 14. 1 Currents and Charges as Sources of Fields Here we discuss how a given distribution of currents and charges can generate and...

Ngày tải lên: 13/08/2014, 02:20

... (180 km/hr) veloc- ity resolution at a 3-GHz carrier frequency, would require B = 5 MHz and T = 1 msec, resulting in the large time-bandwidth product of BT = 5000. Such large time-bandwidth products ... quadrature weights and points h = - wp^2 * tf * J1over(wp*sqrt(x.^2 - tf^2)) .* exp(j*w0*(t(i)-x)); Ez(i) = exp(j*w0*(t(i)-tf)) + w’*h; % exact output Es(i) = exp(j*w0*t(i)-j*k0*tf...

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... half-wave, (c) layer-1 is quarter- and layer-2 half-wave, and (d) layer-1 is half- and layer-2 quarter-wave. Show that the reflection coefficient at interface-1 is given by the following expressions ... (5.2.3) and (5.2.4). 5.3. Reflected and Transmitted Power 159 5.3 Reflected and Transmitted Power For waves propagating in the z-direction, the time-averaged Poynting vector has only...

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... Eqs. (15.3.5) and (15.3.8), we obtain: G max = e a  πd λ  2 (15.3.9) Antennas fall into two classes: fixed-area antennas, such as dish antennas, for which A is independent of frequency, and fixed-gain antennas, ... merit will be the quantities G RS /T RS and G RE /T RE . We may define the uplink and downlink SNR’s as the signal-to-system-noise ratios for the indi- vidual antennas...

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... the 3-dB and first-null widths in radians and degrees: Δθ 3dB = 0. 5144 λ a = 29.47 o λ a ,Δθ null = 1.22 λ a = 70 o λ a (17.9.5) The 3-dB angle is θ 3dB = Δθ 3dB /2 = 0.2572λ/a = 14. 74 o λ/a and ... Stratton-Chu and Kirchhoff diffraction integral for- mulas of Eq. (17.12.1) and (17.12.2) by using the identity (C.42) of Appendix C and replacing ∇ ∇ ∇  ·E = 0 and ∇ ∇ ∇  ×E =−...

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... plane waves propagating in dielectrics, conductors, and birefringent me- dia, (b) guided waves propagating in hollow waveguides, transmission lines, and optical fibers, and (c) propagating waves ... jωD is the total current in the right-hand side of Amp ` ere’s law and accounts for both conducting and dielectric losses. The time-averaged version of Poynt- ing’s theorem is discu...

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... other. Examples of such waves are the evanescent waves in total internal reflection, various guided-wave problems, such as surface waves, leaky waves, and traveling-wave antennas. The most famous ... forward-moving) E (z)= A( ˆ x +j ˆ y)e −jkz (left-polarized, forward-moving) E (z)= A( ˆ x −j ˆ y )e jkz (left-polarized, backward-moving) E (z)= A( ˆ x +j ˆ y )e jkz (right-polarized, b...

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... k e , show that D x = 0 and E x /E y =−j 2 / 1 . Eq. (4.7.4) and the results of Problem 4 .14 lead to the so-called Appleton-Hartree equations for describing plasma waves in a magnetic field ... appropriate linear combinations. For example, we define the right-polarized (forward-moving) and left-polarized (backward- moving) waves for the {E + ,H + } case: E R+ = 1 2  E + −jηH + ...

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... Structures r= -0 .1000 -0 .2000 -0 .4000 0.5000 A= 1.0000 1.0000 1.0000 1.0000 -0 .1000 -0 .1200 -0 .2000 0 -0 .0640 -0 .1000 0 0 -0 .0500000 B= -0 .1000 -0 .2000 -0 .4000 0.5000 -0 .1880 -0 .3600 0.5000 0 -0 .3500 0.5000 ... as bandstop or bandpass filters. Quarter-wave phase-shifted fiber Bragg gratings act as narrow-band transmission filters and...

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... as p-polarization, π-polarization, or TM po- larization, the electric fields lie on the plane of incidence and the magnetic fields are Fig. 7.1.1 Oblique incidence for TM- and TE-polarized waves. 7.1. ... k 2 0 (n 2 −n 2 sin 2 θ) is negative and k  z becomes pure imaginary. In this case, the real-parts in the right-hand side of Eq. (7.16.8) are zero, showing that |ρ TE |=|ρ TM |=1 an...

Ngày tải lên: 13/08/2014, 02:20