Patent ID: 7885144

Claim:
A system comprising: a transmitter to transmit a transmit signal; a receiver to receive a sequence of echoes at a corresponding sequence of time instances; an amplifier to amplify said sequence of echoes and to generate a corresponding sequence of amplified signals, said amplifier comprising: an operational amplifier having an output terminal and an input terminal; and a first impedance and a second impedance configurable to provide a desired impedance ratio according to a set of configuration signals, said first impedance being provided to couple an input signal to said input terminal and said second impedance being coupled as a feedback impedance between said output terminal and said input terminal whereby a gain provided by said operational amplifier is determined by the impedance ratio; and a gain control block to receive a sequence of desired gains for said sequence of time instances, said gain control block to generate said set of configuration signals to obtain said impedance ratio which correspond to each of said sequence of desired gains for corresponding time instances.