Electromagnetic Waves and Antennas combined - Chapter 11 doc

... U FBG U spacer U FBG , or, explicitly:  V 11 V 12 V ∗ 12 V ∗ 11  =  U 11 U 12 U ∗ 12 U ∗ 11  e jβd 0 0 e −jβd  U 11 U 12 U ∗ 12 U ∗ 11  (11. 5.10) where the U ij are given in Eq. (11. 5.5). It follows that ... are: V 11 = U 2 11 e jβd +|U 12 | 2 e −jβd ,V 12 = U 12  U 11 e jβd +U ∗ 11 e −jβd  (11. 5 .11) The reflection coefficient of the compound grating will be...

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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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... 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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... = 40 dB) Taylor-Kaiser [111 4]: b = 6(R +12) 155 Dolph-Chebyshev [111 2]: b = 1 + 0.636  2 R a cosh   acosh 2 (R a )−π 2  2 where R and R a represent the sidelobe level in dB and absolute units, ... antennas being synchronized with atomic frequency standards, and then the recorded signals are digitally cross-correlated and processed off-line. The achievable resolution is about...

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... windowing 3. Woodward-Lawson frequency-sampling design 4. Narrow-beam low-sidelobe design methods 5. Multi-beam array design Next, we establish some common notation. One-dimensional equally-spaced arrays are ... pattern, A(ψ)= N−1  n=0 a n e jψn (20 .11. 2) into (20 .11. 1), we may express the performance index J as a Rayleigh quotient involving the so-called prolate matrix [111 7 ,112 5]: J...

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... the particular forms of Eq. (21.3 .11) in the delta-gap and plane-wave cases. In the delta-gap case, we have E in (z)= V 0 δ(z) and the integral on the right-hand side can be done trivially, giving:  h −h F(z ... impedance matrices Z and ¯ Z for N=2M+1=201. M, and the use of the approximate kernel causing oscillations at the end-points of the antenna (and at the center for delta-gap...

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... field. If antenna-2 is open-circuited and the z-component of the electric field generated by antenna-1 and incident on antenna-2 is E 21 (z), then according to Eq. (21.5.6), the induced open-circuit voltage ... Z 11 − Z 12 Z 21 Z 22 = Z 11  1 − Z 2 21 Z 2 11  where we used Z 12 = Z 21 and Z 22 = Z 11 . The ratio Z 2 21 /Z 2 11 quantifies the effect of the coupling and the dev...

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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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... t)= 1 2π  ∞ −∞ e j(ωt−ωt 0 −kz) e jωt 0 ˆ E( 0, ω)dω (3.2 .11) and assume that t<t 0 +z/c. A consequence of the permittivity model (1 .11. 11) is that the wavenumber k(ω) has singularities only in the upper-half ω-plane and is analytic in ... 87 Thus, the integrand of Eq. (3.2 .11) is analytic in the lower-half ω-plane and we may replace the integration path along the real axis by t...

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