aaron_do wrote on Mar 12th, 2014, 2:46am:Good to hear! But after looking again at one of your previous posts, you mentioned that after adding an output matching network, S11 improved from -7.6 dB to -99 dB. Is that just a typo and you meant after adding an input matching network? Or did you accidentally switch the ports... :P
Anyway since you got it working, don't worry about it...
Aaron
Hi, Aaron.
I intended to mention it before but didn't.
I did input/output matching as follows.
1. Do output matching first.
After this I got really good S22. I don't remember now but it is very small.
2. Do the input matching by choosing the appropriate values of Ls and Lg.
After this I got a very good S11, it is about -99dB. However, S22 now degraded.
Now, input matching is really good while output one is not so good.
When I wrote that post, I used this circuit along with all values calculated above.
I remeasured S parameters like this:
Before adding output matching network:I removed the output matching and measure S parameters.
After adding output matching network:I recovered the output matching calculated previously and measured S parameters.
That explained why S11 is good after adding output network.
I think the replacement of TSMC components will cause many changes and I need to optimize again.
By the way, I just measure the power consumption. It is about 8mW. Do you think it is too large?
I am thinking about reducing it by lowering bias voltage Vgs. I choosed Vgs = 0.6V.