10.08.2013 Views

III. Gm-C Filtering - Epublications - Université de Limoges

III. Gm-C Filtering - Epublications - Université de Limoges

III. Gm-C Filtering - Epublications - Université de Limoges

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

B.2.c IIP2 measurement<br />

To measure the input referred second or<strong>de</strong>r intercept point, two tones are applied at<br />

low (f1) and high (f2) frequencies. The RF filter is centred on fwanted, and the tones frequencies<br />

are chosen so that the intermodulation product (at f2-f1) is very close to the wanted signal. A<br />

quite low power level of the wanted signal is chosen in or<strong>de</strong>r to allow a good measurement of<br />

the second or<strong>de</strong>r intermodulation ratio IMR2, <strong>de</strong>picted on Figure 204, which is the level<br />

difference between the level of the intermodulation product and the level of the wanted<br />

channel. The IMR2 level is related to the two interferer tones levels, which have to be<br />

specified.<br />

There is a direct relation between IMR2 and IIP2:<br />

IIP2 IMR2<br />

+ Pin<br />

_ wanted<br />

where PInputTone is the input tone power level.<br />

= , (B.29)<br />

Figure 204. Measurement of IMR2<br />

- 197 -

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!