5 FSK WLAN filters

>> Now, let's talk about
the two Band-pass Filters.

See we have two band pass filters right

here that are coming out
of this power splitter.

One is at 2.4 gigahertz and
the other is at 2.6 gigahertz,

and that's because we're using
these for the zero and the

one of our digital system.

So at the moment,

we don't know if our signal is 2.4 or
2.6 gigahertz gets one or the other.

So we have a filter at the top,

that's 2.4 and so at
the bottom that passes 2.6.

If you look really closely,

you will see that
these lines that are going

along like this are not actually attached,

see there's actually a hole between

these two lines look really closely
and see if I can zoom in on that.

You are here to see those lines
really are not attached.

The signal goes through because
it's high frequency and it

actually couples across
these capacitive gaps,

each of these gaps are capacitive.

When we model these filters
or when we design them,

they are a series of
inductors and capacitors.

This is actually a picture of
how those circuits are designed.

They are capacitor, inductor,
capacitor, inductor and so on.

You'll learn to design
these circuits when you take

a good signal processing class and to

build them in this particular form
in microwave engineering.

But they are just a series of inductors and

capacitors that make up a band-pass filter.