Patent ID: 8331508

Claim:
A method to perform cancelation of narrow band interference (NBI) in a first signal, the method comprising: (a) slicing the first signal to generate a decision signal; (b) subtracting the decision signal from the first signal to obtain a noise signal; (c) analyzing a frequency spectrum of the noise signal, to prepare a coarse estimate of a fundamental frequency of a narrow band interference in the noise signal; if the coarse estimate does not satisfy at least one predetermined criterion: (d) repeating said (a) slicing, (b) subtracting, and (c) analyzing; if at least said one predetermined criterion is satisfied by the coarse estimate: (e) based on the coarse estimate, adaptively filtering the noise signal to refine the coarse estimate of the fundamental frequency into a fine estimate of the fundamental frequency; (f) preparing a predicted-interference signal at a clock cycle in future based at least partially on the fine estimate of the fundamental frequency; (g) at said clock cycle, subtracting the predicted-interference signal from the first signal, to generate an interference-canceled signal; (h) slicing the interference-canceled signal to generate the decision signal; (i) subtracting from the first signal, the decision signal resulting from (h) slicing, thereby to obtain the noise signal; (j) repeating said (e) adaptively filtering, (f) preparing, (g) subtracting, (h) slicing and (i) subtracting; and (k) recording the fine estimate in a computer memory at least once.