Patent ID: 8396097

Claim:
An electronic device comprising: a first frequency search engine configured to receive a plurality of input values and to determine a frequency of a corresponding signal to be within a first frequency band, the first frequency search engine comprising: a shift register, having an input coupled to an input of the first frequency search engine, configured to store bits of the input values; a combining circuit, having an input coupled to an input of the first frequency search engine, configured to combine bits of the plurality of input values to produce a correlator output; a first delay component, having an input coupled to an output of the combining circuit, configured to serially store a plurality of accumulator values, wherein the serially-stored plurality of accumulator values comprises the correlator outputs; and a feedback circuit, coupled to the first delay component, configured to add a function of an output of the first delay component to a next accumulator value of the first delay component to obtain a modified next accumulator value, wherein the output of the first delay component is coupled to an output of the first frequency search engine; a second delay component, having an input coupled to an input of the first frequency search engine, configured to store at least a portion of the plurality of input values; and a second frequency search engine, having inputs coupled to an output of the second delay component and to an output of the first frequency search engine, configured, using the stored at least a portion of the plurality of input values and the first frequency band, to determine the frequency of the signal to be within a second frequency band, where the second frequency band is a subset of the first frequency band.