Patent ID: 7139220
Filing Date: 2006-11-21
Classification: G01S

Abstract:
1. A pulse-echo ranging system, comprising: a transmitter for generating a transmit signal; a transducer coupled to said transmitter for receiving said transmit signal, emitting said transmit signal as energy pulses, detecting reflected energy pulses and converting said reflected energy pulses to a transmit electrical signal; a receiver coupled to said transducer, said receiver having an input port for receiving said transmit electrical signal, said receiver including a tunable filter for filtering said transmit electrical signal and outputting a filtered signal; a tuning module coupled to said receiver and having an input port for receiving said transmit electrical signal and said filtered signal and outputting a phase correction signal corresponding to a phase difference between said transmit electrical signal and said filtered signal; and a controller having an input port for receiving said phase correction signal and a component for tuning said tunable filter based upon said phase correction signal, so as to minimize said phase difference.