Patent ID: 6052421
Filing Date: 2000-04-18
Classification: G01S,H04B

Abstract:
A method for separating a desired signal from an interfering signal when the desired signal is weaker than the interfering signal, the method comprising the steps of:a) providing a combined signal comprising a desired signal and an interfering signal;b) providing a clock signal having a frequency of Fc;c) sampling the combined signal with an analog to digital converter at the clock frequency Fc;d) storing the sampled combined signal in a data buffer;e) multiplying the stored combined signal by a weighting function to form a weighted combined signal;f) performing a Fourier transform upon the weighted combined signal;g) providing a reference function;h) multiplying the reference function by a weighting function to form a weighted reference function;i) performing a Fourier transform upon the weighted reference function to form a set of reference function coefficients;j) selecting a subset of the reference function coefficients, the subset of the reference function coefficients being selected such that the reference function is described within a predetermined frequency band;k) scaling the subset of reference function coefficients to unity;l) multiplying a real portion of the scaled subset of the reference function coefficients by a real portion of the transformed data of the weighted combined signal and multiplying an imaginary portion of the subset of the reference function coefficients by an imaginary portion of the transformed data of the weighted combined signal to form a product; andm) subtracting the product from the transformed data of the weighted combined signal to form transformed data less interference.