Frequency-independent Smart Interference Suppression for Multi-Standard Transceivers

In this paper an approach is proposed for the suppression of a large unwanted signal without making use of frequency selectivity, but rather by exploiting a nonlinear transfer function. The general requirements for large-signal suppression by this technique are analyzed in the context of a multi-standard transceiver. Also the consequences for weak desired signals and external interference are being discussed. The IIP3 for external interference is derived, and consequences for the noise performance. The proposed technique shows a good IIP3 performance, but comes with a penalty of increasing the output noise by 3dB because of the spectrum mirroring that takes place.