Sep 5 – 9, 2023
ASU Memorial Union (2nd Floor)
US/Arizona timezone
GRCon23 will be running from Tuesday Sept 5 to Saturday Sept 9 this year.

Lo and behold, no LO! Direct Sampling techniques in SDR

Sep 5, 2023, 3:20 PM
Arizona (MU 221) (ASU Memorial Union 2nd Floor)

Arizona (MU 221)

ASU Memorial Union 2nd Floor

Talk Digital Signal Processing Main Track


Martin Braun (GNU Radio)


Most available Software Defined Radio peripherals use local oscillators (LOs), mixers and filters to move signals of interest into the desired bands and center frequencies. With the advent of more powerful ADCs and DACs, we are able to build SDRs that don't require analog components, and instead use direct sampling techniques.

However, this puts some burden on the user, because the lack of analog flexibility means that limits imposed by the theory of digital sampling become limits of the overarching SDR application. In this foundational talk, we go back over the basics of digital sampling, effects of sampling around Nyquist zone borders, and demonstrate how some typical applications may need to be restructured.

Talk Length 30 Minutes
Link to Open Source Code

Primary author

Martin Braun (GNU Radio)

Presentation materials