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

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See we have two band pass filters right

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here that are coming out[br]of this power splitter.

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One is at 2.4 gigahertz and[br]the other is at 2.6 gigahertz,

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

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one of our digital system.

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So at the moment,

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

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So we have a filter at the top,

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

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If you look really closely,

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you will see that[br]these lines that are going

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along like this are not actually attached,

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see there's actually a hole between

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

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You are here to see those lines[br]really are not attached.

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The signal goes through because[br]it's high frequency and it

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actually couples across[br]these capacitive gaps,

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each of these gaps are capacitive.

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When we model these filters[br]or when we design them,

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they are a series of[br]inductors and capacitors.

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

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They are capacitor, inductor,[br]capacitor, inductor and so on.

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You'll learn to design[br]these circuits when you take

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a good signal processing class and to

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build them in this particular form[br]in microwave engineering.

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But they are just a series of inductors and

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capacitors that make up a band-pass filter.