Electromagnetic Waves and Antennas combined - Chapter 12 docx

... Eqs. (12. 12.2) and (12. 12.3).  Example 12. 12.2: It is desired to match a 200 ohm load to a 50 ohm source at 500 MHz. Design L-section and Π-section matching networks and compare their bandwidths. Solution: ... as (a) quarter-wavelength single- and multi-section transformers; (b) two-section series impedance transformers; (c) single, double, and triple stub tuners; and (d) L-...

Ngày tải lên: 13/08/2014, 02:20

... diffint(0,sb,0)); va = hband(sa,1); % 3-dB bandedge for H-plane pattern vb = hband(sb,0); % 3-dB bandedge for E-plane pattern The mainlobes become wider as σ a and σ b increase. The 3-dB bandedges corre- sponding ... Reflector Antennas Reflector antennas are characterized by very high gains (30 dB and higher) and narrow main beams. They are widely used in satellite and line-of-sight...

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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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... (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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... 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 +  E L+ = 1 2  E + +jηH +   E + = ... wavenumber k + and backward with k − , and the reverse is true of the E − (z) component. The forward-moving component of E + and the backward-moving component...

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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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... Structures r= -0 .1000 -0 .2000 -0 .4000 0.5000 A= 1.0000 1.0000 1.0000 1.0000 -0 .1000 -0 .120 0 -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. ... moving interface as shown in Fig. 7 .12. 1. Show that the Doppler-shifted frequencies of the reflected and transmitted waves are still given by Eqs. (7 .12. 14) and (7 .12. 16). Mor...

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... = sqrt((r(1)^2*(1-r(2)*r(3))^2 - (r(2)-r(3))^2)/(4*r(2)*r(3)*(1-r(1)^2))); de2 = acos(c); G2 = (r(2)+r(3)*exp (-2 *j*de2))/(1 + r(2)*r(3)*exp (-2 *j*de2)); de1 = (angle(G2) - pi - angle(r(1)))/2; if ... (degrees) F 1 , F 2 TE and TM bandwidths TM band TE band Fig. 8.8.6 TM/TE bandgaps versus angle for n H = 3, n L = 1.38 and n H = 2, n L = 1.38. We note that the TE band...

Ngày tải lên: 13/08/2014, 02:20