Need good tutorial/design example on broadband mutistage impedance matching.

Books I like: Wes Hayward - Introduction to Radio Frequency Design or Experimental Methods in RF Design.

piglet

As a general rule the broader the impedance match the more components that you need to use. I don't know if you're doing all lumped or loved and distr ibuted or all distributed but nevertheless the concept Remains the Same. If you have a reasonable idea of the source impedance and the load impedance of the two amplifiers you ought to be able to play around with a RF program and empirically get there

I don't think Chris Bowick handles really broadband matching, unless you think an octave or two is broadband, that is.

If anyone can do significantly better than 3 decades, speak up! I want to talk to you!

Jeroen Belleman

Well, transformers. And amplifiers, if you don't require passive solutions.

Broadband impedance matching isn't quite the same as the narrowband case. The circuit needs to be right, by default. Either the circuit is designed around system impedance in the first place, or transformers are used to match it. You can fudge the band edges (both HF and LF), using RLC impedance matching -- filtering -- but only by about an octave.

A principle that applies to the narrowband case as well -- that is, using higher order networks (giving tighter band skirts) to extend bandwidth modestly.

Tim

It's a little more math-heavy than some other introductory textbooks though so it doesn't hurt to brush up on a bit of calculus/linear algebra before heading in

I have both and wholeheartedly recommend them.

I have his RF Design book and I find it invaluable.

Sure. I have it too and it's very nice, but not for broadband matching.

Jeroen Belleman

Not relevant.

I routinely use transmission line transformers to effect impedance matching over three decades of frequency between to real impedance levels. Sometimes, in specific cases, I can stretch that a bit. My record is six decades in a 25 to

Jeroen Belleman

When I am matching 50 ohms to 50 ohms I can match 100 decades with a 50 ohm load cable.

Do tell. Even if your cable were good to 100 GHz, 100 decades below that is a good 10**71 times the age of the universe.

Cheers

Phil Hobbs

You're both posers. I can match 377 ohms to 377 ohms over a 8.0795098 x

Tim

I was starting at dc and going up. Now i guess your point is that there really isnt dc if you dont wait forever, so point taken.

Well, I did impedance-match a 200-THz antenna over about a 40-THz bandwidth, so I win for absolute bandwidth if not fractional. ;)

Cheers

Phil Hobbs

As long as you're not counting optical 'impedance matching'..ie AR coatings.

George H.

Such a buzzkill. ;)

Cheers

Phil Hobbs