c. The height determines the amount of power we can put into the
waveguide without arcing.
The greater the height, the more power we can
inject into the guide.
d. The width determines the lowest frequency we can send down the
waveguide. The wavelength of the lowest frequency is twice the width of the
guide.
e. Rectangular waveguide sometimes has larger dimensions than those
just mentioned. Sometimes, waveguide is round instead of rectangular. We
will discuss round waveguide later in the lesson.
8.
Energy in the waveguide is contained in the E and H fields.
The RF energy inside the waveguide is contained in the E and H
fields just as it is in resonant cavities. You will see in this lesson how
these fields are positioned in the waveguide and how they travel from one
end to the other.
9.
A brief summary.
a. A waveguide is a hollow pipe, usually rectangular, of
specific
dimensions, used as a transmission medium for guiding microwaves.
b. Waveguide is commonly called plumbing.
c. Waveguide is usually a little over one-half wavelength wide, less
than one-quarter wavelength high, and long as required.
d. Waveguide is an efficient transmission medium because it has very
little loss due to skin effect, dielectric, and radiation.
e. We said that the RF energy inside waveguide is contained in the E
and H fields just as it is in resonant cavities. Now let's look at the way
these fields are contained in waveguides.
10. Positioning of E and H fields in waveguide.
a. You know from resonant cavities, that we can confine electric and
magnetic fields in a hollow chamber. We did this with the electrical energy
applied to a resonant cavity. You also found out that a resonant cavity is
constructed in such a way that the fields within the cavity are completely
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