Patent ID: 8179260

Claim:
A method of processing a transponder signal received from a transponder to identify the transponder, the method comprising: providing a first signal from the transponder signal, the first signal having a first and a second characteristics; providing a second signal that is different in phase with respect to the first signal, the second signal having a first and a second characteristics; generating a first transformed signal by altering the first characteristic of the first signal and retaining the second characteristic of the first signal to provide the first transformed signal; the first transformed signal comprising squaring a value of the first signal and retaining a sign of the first signal to provide the first transformed signal; generating a second transformed signal by altering the first characteristic of the second signal and retaining the second characteristic of the second signal to provide the second transformed signal; the second transformed signal comprising squaring a value of the second signal and retaining a sign of the second signal to provide the second transformed signal; and obtaining information incorporated in the transponder signal using a combination of the first transformed signal and the second transformed signal.