Radio frequency identification interrogator signal processing system for reading moving transponders

摘要: An RF/ID interrogator recovers a backscattered data signal from moving transponder by combining the received in-phase (I) and quadrature-phase (Q) components of in manner that cancels out amplitude nulls phase reversals caused movement transponder. More particularly, comprises radio having transmitter portion to provide an RF carrier receiver receive I Q signals A bandpass filter is coupled remove direct current (DC) Q. processor executes stored instructions combine filtered recover original therefrom. In embodiment invention, estimates angle β(t) between calculating arctangent ratio signals. Thereafter, summing product cosine estimated with sine β(t).