As we known, you can use a uhd.tune_request(f_center + f_doppler, f_doppler)
to keep the RF LO frequency constant.
Are there a uhd.tune_request(f_center + f_doppler, f_doppler)-like api in limesdr?
Not that I know of, but @IgnasJ could confirm and if this is the case, you could add an issue to the Lime Suite GitHub tracker with a feature request.
Hi,
I am not sure how uhd api works and there is no function like that in LMS API. If you want to perform digital shift while RF PLL frequency stays the same, then LMS NCO can be used:
LMS_SetNCOFrequency() - allows you to set 16 NCO frequencies, but it should enable the first one (index 0) and if other values are set to 0 then up/down should be based on sign of the first value.
However if automatic (based on sign) up/down convert is not set correctly or you want to switch between preset NCO frequencies use:
LMS_SetNCOIndex()
Note that shift will be limited by RF sampling rate and I recommend to use LMS_SetClockFreq() to set SXR/SXT frequency when setting NCO manually as LMS_SetLOFrequency() may utilize NCO to achieve some frequencies (e.g. <30MHz).
Yes! This is something like what we need. But I’m not sure cause your vague documents. Could you give me some detail information about these API? Sample codes is appreciated too.
Thanx.