Patent ID: 6230000
Filing Date: 2001-05-08
Classification: H03D

Abstract:
A product detector for detecting a signal of interest at an input frequency, and producing baseband in-phase and quadrature signals which represent the signal of interest, said product detector comprising:an input port;an in-phase output port;a quadrature output port;a commutating switch having an input coupled to the input port of the product detector, and having a zero degree output coupled to the in-phase output port, a 90 degree output coupled to the quadrature output port, a 180 degree output, and a 270 degree output, wherein the commutating switch couples the input to each of the four outputs in a periodic fashion at a rate of substantially four times the input frequency, thereby coupling the input to each of the four outputs substantially once during each period of the input frequency;a first charge storage device coupled between the zero degree output and a reference potential;a second charge storage device coupled between the 90 degree output and the reference potential;a third charge storage device coupled between the 180 degree output and the reference potential; anda fourth charge storage device coupled between the 270.degree. degree output and the reference potential.