Method and system for down-converting and electromagnetic signal

摘要

Methods for down converting a modulated carrier signal to a demodulated baseband signal are described herein. The method requires that a first portion of energy is transferred from the modulated carrier signal, and stored at a first storage device when a first switch is on. At least some of the energy stored in the first storage device is discharged when the first switch is off. The method further comprises transferring a second portion of energy from the modulated carrier signal, storing at a second storage device the second portion of transferred energy when a second switch is on, and discharging at least some of the energy stored in the second storage device when the second switch is off. A down-converted in-phase baseband signal portion is generated from the energy accumulated in the first storage device while both the charging and the discharging occurs, and a down-converted inverted in-phase baseband signal portion is generated from the energy accumulated in the second storage device while both the charging and the discharging occurs, and the two portions are combined with a first differential amplifier circuit to form a down-converted differential in-phase baseband signal.

主权项

1. A system for frequency down-converting a modulated carrier signal to a demodulated baseband signal, comprising:
a first switch that receives a first portion of energy from the modulated carrier signal during a sampling aperture with a specified frequency of a first control signal that controls when the first switch is on and when the first switch is off; a first storage device which stores the first portion of energy from the modulated carrier signal output by the first switch when the switch is on the first storage device having previously accumulated energy from the modulated carrier signal as a first accumulation of energy, the first portion of energy being added to the first accumulation of energy to result in a second accumulation of energy, discharges at least some of the second accumulation of energy when the first switch is off so as to leave a third accumulation of energy stored at the first storage device, and outputs a down-converted in-phase baseband signal portion of said modulated carrier signal derived from the energy stored at the first storage device both while the first switch is on and while the first switch is off; a second switch that receives a second portion of energy from the modulated carrier signal during a sampling aperture with a specified frequency of a second control signal that controls when the second switch is on and when the second switch is off; a second storage device which stores the second portion of energy from the modulated carrier signal output by the second switch when the second switch is on, the second storage device having previously accumulated energy from the modulated carrier signal as a fourth accumulation of energy, the second portion of energy being added to the fourth accumulation of energy to result in a fifth accumulation of energy, discharges at least some of the fifth accumulation of energy when the second switch is off so as to leave a sixth accumulation of energy stored at the second storage device, and outputs a down-converted inverted in-phase baseband signal portion of said modulated carrier signal derived from the energy stored at the second storage device both while the second switch is on and while the second switch is off; and wherein said down-converted in-phase baseband signal portion is generated from both said second accumulation of energy and said third accumulation of energy; wherein said down-converted inverted in-phase baseband signal portion is generated from both said fifth accumulation of energy and said sixth accumulation of energy; 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.