By "no IF frequency" he meant the LO frequency is the same as the RF frequency. This is called a zero-IF receiver, or direct conversion.
http://en.wikipedia.org/wiki/Direct-conversion_receiver --n On Wed, Oct 5, 2011 at 4:08 PM, Brook Lin <[email protected]> wrote: > > Hi All, > > I am confused on this reply. The reply said that "With the RFX2400, and most > of the high frequency usrp daughtercards, > there is no IF frequency". How is that possible? For RFX2400 the RF range is > from 2.3GHz to 2.9GHz, the ADC rate for USRP1 is 64MS/s. If there is no IF > frequency, the ADC rate is obviously too low. There must be RF front-end on > the daughterboard to tune the RF to the IF. Right? If so, my question is > what the IF is? Obviously, f_IF = f_RF - f_LO. (1) Are we setting the f_LO > when we tune the usrp by usrp.tune(self.u, 0, self.subdev, target_freq)? (2) > How to figure out f_IF for different daughterboards? > > Thanks in advance, > Brook > > > > Jason Uher wrote: >> >>> If I am using RFX2400 then what is the IF frequency and can we change >>> this >>> to some other value? Correct me if the question I asked is wrong. >> >> With the RFX2400, and most of the high frequency usrp daughtercards, >> there is no IF frequency. The samples you receive (or send) from the >> usrp.source_x (or usrp.sink_x) are baseband I and Q values. >> >> Jason >> >> >> _______________________________________________ >> Discuss-gnuradio mailing list >> [email protected] >> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio >> >> > > -- > View this message in context: > http://old.nabble.com/Intermediate-frequency-question-tp23514126p32598120.html > Sent from the GnuRadio mailing list archive at Nabble.com. > > > _______________________________________________ > Discuss-gnuradio mailing list > [email protected] > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > _______________________________________________ Discuss-gnuradio mailing list [email protected] https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
