Software defined radio techniques require digital signal processing. Digital switching in the radio frequency (RF) environment generates unwanted harmonics and adjacent channel interference. Resolving these issues requires expensive analog filtering or digitally intensive and power-hungry methods such as raised cosine filters, sigma-delta modulation, and digital predistortion.
Researchers at the University of California, Santa Barbara have discovered a power digital, low-complexity switching technique for managing out of band signal leakage and switching harmonics. By adding precise switching intervals on the edges of each digital transition, the unwanted interference is eliminated allowing the digital RF front-end to be standards-compliant wideband at lower power consumption than sigma-delta modulation. This technique can also be executed with lower system requirements than the current industry alternatives.