defect ground structure

hi pewang:
these papers are exactly suitable for me!
i'm working on how to eliminate 2th and 3th harmonics of a s-band class C high power amplifier outping 130w .......can u give me some advices? In my situation,using DGS may be unaccessible for me...so i want to get traditional methods to eliminate harmonic....so can u share these papers as follows:
1..B.Kopp and D.D. Hestion,"High efficiency 5-W power amplifier with harmonic tuing,"in IEEE MTT-S Int.Microwave Dig.,New York,NY,May 1988,pp.839-842

2.J.R.lane,R.G.Freitag,H.-K Hahn,J.E. Degenford, and M. Cohn,"High-efficiceny 1-,2-,and 4-w class B FET power amplifiers"IEEE Trans. Microwave Theory Tech.vol.34.pp.1318-1325,Dec,1986.

thanx alt~~~~~~~~~~~mybe i need "harmonic tuning" collection

BTW,how can i get free IEEE papers?

It's a pity I have non experience on Class C PA design. It seemed mostly we eliminate the 2nd or 3rd order harmonics by either tune the harmonic impedance at output to zero(use lambda/4 open stub) or a lowpass filter.
Also these paper I got from one of my friends' collections.But I know there are some kind-hearted men on this board who can provide you papers you wants.You need post one request papers topic.

Here are some things to consider. Use an ordinary band pass filter of the topology that goes either high or low impedance out of band. Whatever your amplifier likes to keep it from parasitic oscillations.

You can combine the bandpass filter with a parallel band stop one in a sort of diplexer with the out of band stop filter terminated in a resistive load. This will present a 50 ohm load the amplifier at all frequencies keeping it more stable.

On the lower bands I use m derived image parameter low pass filters and put the notches at the harmonics.

This DGS is nothing more than a subset of Brillouin zones. He wrote a book around 1950 titled Wave Propagation in Periodic Structures. In it he showed how using alternating reactive periodic loading on a transmission line can be used to further shape the frequency response and impedance levels. There is nothing new under the sun.

It's kd

I downloaded the "J.R.lane,R.G.Freitag,H.-K Hahn,J.E. Degenford, and M. Cohn,"High-efficiceny 1-,2-,and 4-w class B FET power amplifiers"IEEE "..for you..

mail me at: kanna.dassan@gamil.com...... and get the file...

:D