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Solutions for a uniform rectangular duct

Consider a duct with rectangular cross-section with halfwidths $a$ and $b$ (cross-sectional area is $S=4 a b$) as shown in figure 2.7.
Figure 2.7: Rectangular waveguide with halfwidths $a$ and $b$
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The multimodal treatment discussed for cylindrical geometry was due to Pagneux et al [32]. A geometry was also discussed in [32] in which the walls are flat and parallel. The $z$ axis went along the pipe axis, the pipe had a finite width in the $y$ direction and was infinite in width along $x$. What follows is new work using the same method which formulates the problem of multimodal propagation in rectangular guides which are finite in both the $x$ and $y$ directions.


Jonathan Kemp 2003-03-24