Have you tried adjusting the magnitude of the modulating baseband signal? Does that make a difference.
My guess is that the leakage path isn’t through the VGA but rather through something else in the package. In which case, no amount of software mods will reduce it. Sent from my iPhone > On May 28, 2020, at 1:50 PM, guowang qiu via USRP-users > <[email protected]> wrote: > > > Hi all, > > We use USRP b210 as a signal generator, and adjust the tx gain to make the tx > power from - 90dbm to 0dbm. USRP b210 works fine in 2.4GHz frequency band, > but it has a very strong LO signal leakage at frequencies higher than 5GHz. > In my test, the frequency of baseband (cos signal source) is set to 1MHz, so > LO signal leakage and single tone signal can be easily distinguished. When > the tx gain is set from 0 to 30 db, the strength of the LO signal hardly > changes, and it is higher than the strength of the single tone signal. With > the increase of tx gain, the strength of single tone signal will increase > obviously. It seems that the local oscillator signal generated by the PLL in > ad9361 bypasses the internal adjustable gain power amplifier and leaks > directly to the antenna port. > Is it possible to reduce the local leakage by modifying the UHD source code? > > Best regards, > Damon > _______________________________________________ > USRP-users mailing list > [email protected] > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com _______________________________________________ USRP-users mailing list [email protected] http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
