Analog feedback shift register
An analog feedback shift register is a generalization of the linear-feedback shift register.
While binary LFSRs require less power to generate spread spectrum signals than AFSRs, AFSR receivers require less power to synchronize to those signals than binary LFSR receivers.
As of 2005, AFSRs are still in research.
AFSR techniques could make spread-spectrum receivers cost less and have longer battery lifetimes.
