Patent ID: 9246736
Filing Date: 2016-01-26
CPC Classification: H03C,H03D,H04B,H04L

Claim Text:
1. A system for frequency down-converting a modulated carrier signal to a demodulated baseband signal, comprising: a first switch coupled to a first control signal which comprises a first sampling aperture with a specified frequency, wherein the first switch is on during the first sampling aperture and wherein the first switch is off outside the first sampling aperture; a first energy storage element, coupled to said first switch, that outputs a down-converted in-phase baseband signal portion of said modulated carrier signal; a second switch coupled to a second control signal which comprises a second sampling aperture with a specified frequency, wherein the second switch is on during the second sampling aperture and wherein the first switch is off outside the second sampling aperture; a second energy storage element, coupled to said second switch, that outputs a down-converted inverted in-phase baseband signal portion of said modulated carrier signal; wherein the first and second control signals each control a charging and discharging cycle of their respective energy storage element so that for each switch a portion of energy from the modulated carrier signal is transferred to the respective energy storage element when the respective switch is on during the charging cycle, and a portion of previously transferred energy is discharged during the discharging cycle for each respective switch when the respective switch is off; wherein for each respective energy storage element, the energy discharged during any given discharge cycle is not completely discharged, with the remaining undischarged energy from the given discharge cycle becoming an initial condition for a next charging cycle that begins immediately following the given discharge cycle; wherein said down-converted in-phase baseband signal portion is derived from energy accumulated at said first energy storage element during both the charging and the discharging cycles for the first energy storage element; wherein said down-converted inverted in-phase baseband signal portion is derived from energy accumulated at said second energy storage element during both the charging and the discharging cycles for the second energy storage element; and a first differential amplifier circuit that combines said down-converted in-phase baseband signal portion with said down-converted inverted in-phase baseband signal portion and outputs a first channel down-converted differential in-phase baseband signal.