Dual mode transmitter/receiver and decoder for RF transponder units
First Claim
1. A backscatter transponder reader system, comprising:
- a radio-frequency interrogation signal emitter, adapted for emitting an interrogation signal having a modulated pattern;
a backscatter response receiver, for receiving a backscatter response from a transponder; and
an analyzer for analyzing the backscatter response, to extract information modulated on the radio-frequency interrogation signal by the transponder, without interference from said modulated pattern of said interrogation signal, said analyzer producing a common information pattern output for information encoded differently by a plurality of types of transponders.
0 Assignments
0 Petitions
Accused Products
Abstract
An enhanced backscatter RF-ID tag reader system and multiprotocol RF tag reader system is provided. In a multiprotocol mode, the system emits a non-stationary interrogation signal, and decodes a phase modulated backscatter signal by detecting a stronger phase component from quadrature phase representations or determining phase transition edges in a phase of a received signal. The RF tag reader system predicts or follows the phase of the backscatter signal, thereby avoiding interference from nulls in the received signal waveform due to the non-stationary interrogation signal, relative movement or environmental effects. An acoustic RF-ID tag detection system detects the reradiated signal corresponding to respective transformation of a signal in the tag. Detection of either type of RF-ID tags therefore is possible, and the absence of any tag or absence of any valid tag also determined.
220 Citations
24 Claims
-
1. A backscatter transponder reader system, comprising:
-
a radio-frequency interrogation signal emitter, adapted for emitting an interrogation signal having a modulated pattern;
a backscatter response receiver, for receiving a backscatter response from a transponder; and
an analyzer for analyzing the backscatter response, to extract information modulated on the radio-frequency interrogation signal by the transponder, without interference from said modulated pattern of said interrogation signal, said analyzer producing a common information pattern output for information encoded differently by a plurality of types of transponders. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-
15. A backscatter transponder reading method, comprising:
-
emitting an interrogation signal having a modulated pattern;
receiving a backscatter response from a transponder; and
analyzing the backscatter response, to extract information modulated on said radio-frequency interrogation signal by the transponder, without interference from the modulated pattern of the interrogation signal, producing a common information pattern output for information encoded differently by a plurality of types of transponders. - View Dependent Claims (16, 17, 18, 19, 20, 21, 22, 23, 24)
-
Specification