Patent ID: 7266465

Claim:
An apparatus for confirming a frequency measurement of a received signal comprising a discrete Fourier transform (DFT) module for receiving a sampled digital signal, the DFT module configured to analyze the received sampled digital signal, and output amplitude values at different frequency components, and a threshold comparator for receiving the amplitude values of the frequency components and outputting a thresholded-amplitude value exceeding a predetermined threshold value, wherein a frequency confirmation is provided to a user based on the thresholded-amplitude value, and the DFT module includes the following DFT kernel function: [ ⁢ q 1 , k - 1 q 1 , k q 1 ⁢ k + 1 q 2 , k - 1 q 2 , k q 2 ⁢ k + 1 ⋮ ⋮ ⋮ ⋮ ⋮ ⋮ q n , k - 1 q n ⁢ k q n , k + 1 ⁢ ] where k−1, k, and k+1 are adjacent frequency components, n is the number of time samples used in each DFT analysis, and q is a kernel having four possible values of 1, −1, j and −j, where j is √{square root over (−1)}.