RFID Fast Hop Frequency Hopping
Methods and apparatus, including computer program products, for RFID fast hop frequency hopping. A method including transmitting from a radio frequency identification (RFID) interrogator a continuous wave un-modulated radio frequency (RF) signal from a frequency synthesizer based on digital waveform reconstruction with Direct Memory Access (DMA), the continuous wave un-modulated RF signal conforming to a fast hop frequency hopping protocol in which each hop of a plurality of hops spans at least one bit but less than the totality of bits to be sent from a single RFID device data in a single communications session.
1 . A method comprising:
transmitting from a radio frequency identification (RFID) interrogator a continuous wave un-modulated radio frequency (RF) signal from a frequency synthesizer based on digital waveform reconstruction with Direct Memory Access (DMA), the continuous wave un-modulated RF signal conforming to a fast hop frequency hopping protocol in which each hop of a plurality of hops spans at least one bit but less than the totality of bits to be sent from a single RFID device data in a single communications session.
2 . The method of claim 1 further comprising:
sending one or more commands to cause a RFID device to reply; and
transmitting a continuous wave un-modulated RF signal conforming to the fast hop frequency hopping protocol while listening for a RFID device response.
3 . The method of claim 2 further comprising:
receiving a RFID device response; and
reporting the RFID device response to a computer coupled to the RFID interrogator.
4 . The method of claim 3 in which receiving comprises:
tracking data returned from the RFID device during a hop; and
reconstructing the returned data after RF signal transmission is completed.
5 . The method of claim 1 wherein the fast hop frequency hopping protocol comprises:
frequency hops occurring at rates of up to 10 MHz to 50 MHz for operation complying with 900 MHz Part 15 rules; and
frequency hops occurring up to 100 MHz for operation complying with 2.45 GHz Part 15 rules.
6 . A method comprising:
transmitting from a radio frequency identification (RFID) interrogator a continuous wave un-modulated radio frequency (RF) signal from a frequency synthesizer based on digital waveform reconstruction with a Digital to Analog Converter (DAC), the continuous wave un-modulated RF signal conforming to a fast hop frequency hopping protocol in which each hop of a plurality of hops spans at least one bit but less than the totality of bits to be sent from a single RFID device data in a single communications session.
7 . The method of claim 6 further comprising:
sending one or more commands to cause a RFID device to reply; and
transmitting a continuous wave un-modulated RF signal conforming to the fast hop frequency hopping protocol while listening for a RFID device response.
8 . The method of claim 7 further comprising:
receiving a RFID device response; and
reporting the RFID device response to a computer coupled to the RFID interrogator.
9 . The method of claim 8 in which receiving comprises:
tracking data returned from the RFID device during a hop; and
reconstructing the returned data after RF signal transmission is completed.
10 . The method of claim 6 wherein the fast hop frequency hopping protocol comprises:
frequency hops occurring at rates of up to 10 MHz to 50 MHz for operation complying with 900 MHz Part 15 rules; and
frequency hops occurring up to 100 MHz for operation complying with 2.45 GHz Part 15 rules.
11 . The method of claim 6 wherein the DAC is a Fixed DAC, a Binary Weighed DAC, a R-2R DAC, a Thermometer coded DAC, a Segmented DAC or a Hybrid DAC.
12 . A radio frequency identification (RFID) interrogator comprising:
a microcontroller coupled to a radio frequency (RF) transmitter and a RF receiver;
an antenna coupled to the RF transmitter and RF receiver; and
the microcontroller causing the RF transmitter to transmit a continuous wave un-modulated radio frequency (RF) signal from a frequency synthesizer based on digital waveform reconstruction with Direct Memory Access (DMA), the continuous wave un-modulated RF signal conforming to a fast hop frequency hopping protocol in which each hop of a plurality of hops spans at least one bit but less than the totality of bits to be sent from a single RFID device data in a single communications session.
13 . The RFID interrogator of claim 12 wherein the fast hop frequency hopping protocol comprises:
frequency hops occurring at rates of up to 10 MHz to 50 MHz for operation complying with 900 MHz Part 15 rules; and
frequency hops occurring up to 100 MHz for operation complying with 2.45 GHz Part 15 rules.
14 . A radio frequency identification (RFID) interrogator comprising:
a microcontroller coupled to a radio frequency (RF) transmitter and a RF receiver;
an antenna coupled to the RF transmitter and RF receiver; and
the microcontroller causing the RF transmitter to transmit a continuous wave un-modulated radio frequency (RF) signal from a frequency synthesizer based on digital waveform reconstruction with a Digital to Analog Converter (DAC), the continuous wave un-modulated RF signal conforming to a fast hop frequency hopping protocol in which each hop of a plurality of hops spans at least one bit but less than the totality of bits to be sent from a single RFID device data in a single communications session.
15 . The RFID interrogator of claim 14 wherein the DAC is a Fixed DAC, a Binary Weighed DAC, a R-2R DAC, a Thermometer coded DAC, a Segmented DAC or a Hybrid DAC.
16 . The RFID interrogator of claim 14 wherein the fast hop frequency hopping protocol comprises:
frequency hops occurring at rates of up to 10 MHz to 50 MHz for operation complying with 900 MHz Part 15 rules; and
frequency hops occurring up to 100 MHz for operation complying with 2.45 GHz Part 15 rules.