US Patent 7675984 Low complexity, iterative approach to active interference cancellation

Generating a notch in an Orthogonal Frequency Division Multiplexing (OFDM) frequency spectrum includes determining a first active interference cancellation (AIC) tone, comparing the first AIC tone with an amplitude limit, in the event that the first AIC tone exceeds the amplitude limit, constraining the first AIC tone, and determining a second AIC tone based at least in part on the first AIC tone. An Active Interference Cancellation (AIC) tone generator includes an interface configured to receive a plurality of tones, a processing component coupled to the interface, configured to determine a first AIC tone, compare the first AIC tone with an amplitude limit, and in the event that the first AIC tone exceeds the amplitude limit, constrain the first AIC tone, and determine a second AIC tone based at least in part on the first AIC tone.