Patent ID: 7729201

Claim:
A computer system for increasing the signal to noise ratio in a calculated model of an incoming signal comprising a signal processor, at least one transmit transducer and at least one receive transducer wherein the signal processor is programmed to perform the steps of: a) generating a direct sequence of predetermined length; b) normalizing the direct sequence; c) generating a transmitted sequence representing the direct sequence one or more times; d) transmitting the transmitted sequence from the transmit transducer; e) receiving an incoming signal, composed of one or more received echo sequences, from the receive transducer; f) cross correlating the incoming signal with the transmitted sequence; g) identifying chosen received echo sequence from the one or more received echo sequences, based on a cross correlation value; h) deriving a calculated echo sequence corresponding to the chosen received echo sequence; i) removing the calculated echo sequence from the incoming signal; j) adding the calculated echo sequence to a calculated model; and k) repeating f), g), h), i) and j) a predetermined number of times; wherein the calculated model correlates to the incoming signal and has an increased signal to noise ratio.