Electromagnetic Waves and Antennas combined - Chapter 22 doc
Electromagnetic Waves and Antennas combined - Chapter 22 doc
... dB.
22. 7 Hall
´
en Equations for Coupled Antennas
In Sects. 22. 4 and 22. 5, we developed the Hall
´
en-Pocklington equations for coupled an-
tennas, that is, Eqs. (22. 4.8)– (22. 4.9) and (22. 5.1). ... Fig. 22. 3.1. Their
distance along the
x-direction is d and their centers are offset by b along the z-direction.
Fig. 22. 3.1 Parallel linear dipoles.
If antenna-1 is driven...
Electromagnetic Waves and Antennas combined - Chapter 11 doc
... Quarter-wave phase-shifted fiber Bragg grating.
Quarter-wave phase-shifted FBGs are similar to the Fabry-Perot resonators discussed
in Sec. 6.5. Improved designs having narrow and flat transmission bands ... already first-order, the multiple reflection terms
in the above summations are a second-order effect, and only the lowest terms will con-
tribute, that is, the term
m = 1 for the near-end...
Electromagnetic Waves and Antennas combined - Chapter 12 docx
... 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...
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 ... 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...
Electromagnetic Waves and Antennas combined - Chapter 19 doc
... 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 one milli-arc-second.
We ... graphs:
sigma=1e-3; ep0=8.854e-12; er=15; f=1e6; h = 1/4;
n2 = er - j*sigma/ep0/2/pi/f;
th = linspace(0,pi/2,301); c =cos(th); s2 = sin(th).^2;
rho = (sqrt(n2-s2) - n2*c)....
Electromagnetic Waves and Antennas combined - Chapter 20 doc
... 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 ... case.
The 3-dB widths are in the three cases:
Δφ
3dB
= 22. 85
o
, 22. 85
o
, 22. 09
o
. The graphs also
show the 3-dB gain circles intersecting the gains at the 3-dB angles.
20....
Electromagnetic Waves and Antennas combined - Chapter 21 doc
... 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 inpu...
Electromagnetic Waves and Antennas combined - Chapter 1 pps
... 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...
Electromagnetic Waves and Antennas combined - Chapter 2 potx
... 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...
Electromagnetic Waves and Antennas combined - Chapter 3 ppt
... (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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