Because of the high maintenance needed to monitor and filter spammers from the RF Cafe Forums, I decided that it would
be best to just archive the pages to make all the good information posted in the past available for review. It is unfortunate
that the scumbags of the world ruin an otherwise useful venue for people wanting to exchanged useful ideas and views.
It seems that the more formal social media like Facebook pretty much dominate this kind of venue anymore anyway, so if
you would like to post something on RF Cafe's
page, please do.
Below are all of the forum threads, including all
the responses to the original posts.
Post subject: maximum power Posted: Thu Dec 14, 2006 11:36 am
Nov 14, 2006 7:21 pm
can you tell me various design consideration for
getting higher power for the power amplifier?
how should i increase the power of amplifier?
Post subject: Posted: Thu Dec 14, 2006 4:30 pm
Joined: Mon Jun 27,
2005 2:02 pm
One possibility to increase the output power is to match the
power amplifier to maximal output power. You have to match the output to the conjugate of the output impedance.
This however might come on the expense of other design paramaters like linearity or effieicncy.
You can do
Load-Pull measurements. This can be done with a Tuner or by using a CAD tool e.g. ADS. The simulation results are
countours of points on the Smith Chart, which correspond to different output power levels. This indicates to which
impedance the output has to be matched in order to obtain a certain output power. You can also do paramater sweep:
frequency, bias point to see how the output impedance changes and according to that to synthesize the required
matching network. In ADS for example, you can get the contours for several paramaters like ACPR, IMD, output power
etc, and you can design a matching network to a certain impedance which is a trade-off between several paramaters
- the intersection of several countours.
Hope this helps!