Patent ID: 7894789

Claim:
An apparatus for down-converting an electromagnetic signal, the apparatus comprising: an energy transfer device configured to receive the electromagnetic signal and a control signal, to down-convert the electromagnetic signal based on the control signal, and to output a down-converted signal; an analog-to-digital (A/D) converter configured to receive the down-converted signal and to generate a down-converted digital signal; a state machine device configured to receive the down-converted digital signal and to compare the down-converted digital signal to a previous down-converted digital signal; a digital-to-analog (D/A) converter configured to output an analog voltage signal based on the comparison of the down-converted digital signal to the previous down-converted digital signal; a voltage controlled oscillator (VCO) configured to a generate a pulse signal based on the analog voltage signal; and a pulse generator configured to generate aperture pulses in the control signal based on the pulse signal, wherein the aperture pulses are an input to a switch.