Electromagnetic Waves and Antennas combined - Chapter 18 docx

... 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 ... λ/a = 1 .189 λ/a. Thus, the 3-dB widths are in radians and in degrees: Δθ x = 1 .189 λ a = 68.12 o λ a ,Δθ y = 0.886 λ b = 50.76 o λ b (18. 1.11) Example 18. 1.1: Fig. 18...

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... 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-section lumped-parameter reactive ... [978,979]. Possible applications are the matching of dual-band antennas operating in the cellu- lar/PCS, GSM/DCS, WLAN, GPS, and ISM bands, and other dual-band RF applications fo...

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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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... m/s (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 ... 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 .1200 -0 .2000 0 -0 .0640 -0 .1000 0 0 -0 .0500000 B= -0 .1000 -0 .2000 -0 .4000 0.5000 -0 .188 0 -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...

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... interface between a positive- and a negative- index medium, and for propagating waves, we must have k z > 0 and k  z < 0 in order for the power transmitted into the negative-index medium to flow ... (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 widens...

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