Designer’s Guide Community

vivek1214 New Member Offline Posts: 1	IIP2 measurements Apr 08^th, 2008, 10:43am hello, I want to measure IIP2 of my system(BT receiver).center freq 2.44GHz which tones I should take to measure IIP2?
Back to top	IP Logged

Stefan

Senior Member

Offline

Posts: 124

Re: IIP2 measurements
Reply #1 - Apr 9^th, 2008, 12:17am

That strongly depends on the filter characteristics you chose for your system.
You need to use 2 frequencies that can travel through your input filters, across your LNA/Mixer stages and so on, until they reach (downconverted) the lowpass filters and the ADC.
The lowpass filters and bandwidth of your LNA/mixer combination specify the allowed distance between the two carriers, your simulation time requirements specify the minimum distance needed for effective simulation. However, when characterizing a wideband sytem, you should consider using 2.5GHz instead of 2.44GHz for easier use of fractional parameters ...

Back to top

IP Logged

didac

Senior Member

Offline

There's a million
ways to see the
things in life

Posts: 247
manresa,spain

Re: IIP2 measurements
Reply #2 - Apr 9^th, 2008, 12:35pm

Hi,
If you are working with a direct conversion receiver I think that you should choose two tones which their difference results directly in the IF bandwidth(DC to 3dB corner of the IF filter) since they will leak through the mixer (finite RF-LO isolation), then you can compare the resulting IIP2 with the radio spec of adjacent channel level.
Hope it helps,

Back to top

IP Logged

pancho_hideboo Senior Fellow Offline Posts: 1424 Real Homeless	Re: IIP2 measurements Reply #3 - Apr 10^th, 2008, 2:34am See http://www.designers-guide.org/Forum/YaBB.pl?num=1193566207
Back to top	Kita━━━━━━(ﾟ∀ﾟ)━━━━━━ !!!!! http://www7.plala.or.jp/ungeromeppa/flash/kita.html http://www.youtube.com/watch?v=mjIxGh55bMM&feature=related IP Logged