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>> All right, now let's[br]talk about Power Splitter.

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The splitter is used to divide

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the signal that's on the line[br]into two separate parts.

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The reason that we're going to[br]divide it is because I need to know

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if it's 2.4 or 2.6 gigahertz.

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So it's going to go into to[br]band-pass filters in a minute.

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We call this thing a 3dB coupler,

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because 3dB means that it's[br]dividing the power in half,

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and a coupler is the same[br]as a splitter or a divider.

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So you can use this same[br]circuit to either bring

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signals in like here and[br]here and add them up,

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or to put them here and[br]split them down either side.

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So you could call it like[br]a voltage divider in fact, in this case.

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So what we have right here is

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a 3dB coupler with[br]a resistive element right here.

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What happens is in the event[br]that I had things mismatched,

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or very unbalanced on either side,

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this resistor is going to absorb whatever[br]amount of the signal is imbalanced.

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So the signal comes in right here,

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it splits down these two lines,

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and it goes into my band-pass filter.

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There's another cool thing[br]to note right here.

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See how these little quarters[br]have been cut off?

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That's because a high-frequency quarters[br]radiate really well,

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and that's not generally something[br]that you want in your circuit.

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Now, there's one form of 3dB coupler.

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Here is another form of 3dB coupler.

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What you can see right here is that we have

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a 50 Ohm line that goes[br]into two 100 Ohm lines.

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That 200 Ohm lines are in parallel,

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so 100 in parallel with a 100 would be 50.

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So this is match 50 onto[br]this set of 100s right here.

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Once you take microwave engineering,

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you're going to find out that these are[br]actually quarter wave transformers.

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This is a quarter of a wavelength[br]long at 2.4 gigahertz.

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This is a quarter wavelength[br]long at 2.6 gigahertz,

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and they're two quarter wave transformers[br]going down either side,

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that are perfectly[br]matching this 50 Ohm line

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to the next set of[br]50 Ohm lines on either side.