Multi-mode rfid tag architecture

Abstract

A multi-mode RFID tag includes a power generating and signal detection module, a baseband processing module, a transmit section, a configurable coupling circuit, and an antenna section. In near field mode, the configurable coupling circuit is operable to couple the transmit section to a coil or inductor in the configurable coupling circuit to transmit an outbound transmit signal using electromagnetic or inductive coupling to an RFID reader. In far field mode, the configurable coupling circuit is operable to couple the transmit section to the antenna section, and the multi-mode RFID tag then utilizes a back-scattering RF technology to transmit the outbound transmit signal to RFID readers.

1 . A transceiver, comprises:
 a circuit operable to format an outbound signal in a near field mode and in an RF mode, wherein the circuit is configured to format the outbound signal using a first protocol when in the near field mode and format the outbound signal using a second protocol when in the RF mode; and   a transmitter operable to generate an outbound transmit signal and transmit the outbound transmit signal at a first frequency in the near field mode and at a second frequency in the RF mode.   
     
     
         2 . The transceiver of  claim 1 , wherein the first frequency in the near field mode includes at least one of: approximately 135 KHz or less; or approximately 13.56 MHz. 
     
     
         3 . The transceiver of  claim 2 , wherein the second frequency in the RF mode includes at least one of: approximately 2.45 GHz frequency; approximately 860 MHZ to 930 MHz; or approximately 433.92 MHz. 
     
     
         4 . The transceiver of  claim 1 , wherein the transmitter includes:
 a coupling circuit operable to couple the transmitter to a first circuit to transmit the outbound transmit signal using inductive coupling in the near field mode and operable to couple the transmitter to a second circuit to transmit the outbound transmit signal as an RF signal in the far field mode.   
     
     
         5 . The transceiver of  claim 1 , further comprising:
 a power generating module including a power supply.   
     
     
         6 . The transceiver of  claim 1 , comprising:
 a power generating module, wherein the power generating module is operable to convert an inbound receive signal from an RFID interrogator into a supply voltage.   
     
     
         7 . The transceiver of  claim 1 , wherein the first protocol is a first ISO standard defined protocol and wherein the second protocol is a second ISO standard defined protocol. 
     
     
         8 . The transceiver of  claim 1 , wherein the transceiver supports one or more of: amplitude shift keying (ASK) modulation, biphase space modulation or FM0 encoding. 
     
     
         9 . A radio frequency identification (RFID) device, comprises:
 a transceiver operable to receive an inbound receive signal in a near field mode and an RF mode;   at least one circuit configured to decode the inbound receive signal using a first protocol when in the near field mode and decode the inbound receive signal using a second protocol when in the RF mode.   
     
     
         10 . The RFID device of  claim 9 , wherein the first protocol is a first encoding protocol and wherein the second protocol is a second encoding protocol. 
     
     
         11 . The RFID device of  claim 9 , wherein the first protocol is a first ISO standard defined protocol and wherein the second protocol is a second ISO standard defined protocol. 
     
     
         12 . The RFID device of  claim 9 , wherein the transceiver further comprises:
 a coupling circuit operable to couple the RFID device to a first antenna circuit to receive the inbound receive signal using inductive coupling in the near field mode and operable to couple the RFID device to a second antenna circuit to receive the inbound receive signal as an RF signal in the far field mode.   
     
     
         13 . The RFID device of  claim 9 , comprising:
 a power generating module operable in an active mode, wherein the power generating module includes a power supply.   
     
     
         14 . The RFID device of  claim 9 , comprising:
 a power generating module operable in a passive mode, wherein the power generating module is operable to convert an inbound receive signal from an RFID interrogator into a supply voltage.   
     
     
         15 . A transceiver, comprises:
 a circuit operable to encode an outbound signal in a near field mode and in an RF mode, wherein the circuit is configured to format the outbound signal using a first data encoding protocol in a near field mode and a second data encoding protocol in an RF mode.   
     
     
         16 . The transceiver of  claim 15 , further comprising:
 a transmitter operable to generate a transmit signal using the outbound signal and transmit the transmit signal at a first frequency in the near field mode and at a second frequency in the RF mode.   
     
     
         17 . The transceiver of  claim 16 , further comprising:
 wherein the transmitter is further operable to receive a first command in the near field mode; and   wherein in response to the first command, the circuit is operable to generate the outbound signal using the first encoding protocol.   
     
     
         18 . The transceiver of  claim 17 , further comprising:
 wherein the transmitter is further operable to receive a second command in the RF mode; and   in response to the second command, the circuit is operable to generate the outbound signal using the second encoding protocol and transmitting the outbound transmit signal in the RF mode.   
     
     
         19 . The transceiver of  claim 15 , wherein the first frequency in the near field mode includes at least one of: approximately 135 KHz or less; or approximately 13.56 MHz. 
     
     
         20 . The transceiver of  claim 19 , wherein the second frequency in the RF mode includes at least one of: approximately 2.45 GHz frequency; approximately 860 MHZ to 930 MHz; or approximately 433.92 MHz.