Method of simultaneously reading multiple radio frequency tags, RF tags, and RF reader
First Claim
1. A method of identifying RF tags, the method comprising:
- issuing a wireless command using a reader, requesting that RF tags identify themselves;
illuminating a plurality of RF tags with a radio frequency field using the reader;
respective RF tags randomly selecting a radio frequency and a timeslot from a plurality of pre-defined radio frequencies and timeslots;
respective RF tags issuing a wireless response to the command, including information identifying the tag, using the selected radio frequency and timeslot;
receiving the wireless responses with the reader; and
issuing wireless acknowledgements from the reader to RF tags that have been successfully identified responsive to the receiving.
1 Assignment
0 Petitions
Accused Products
Abstract
An RF tag system, comprising an RF reader configured to issue a plurality of different RF commands and to provide a continuous RF illumination field, and a plurality of RF tags respectively including a permanent identification; wherein the plurality of RF tags are configured to respond to a certain RF command from the RF reader by transmitting their respective identifications by way of backscatter modulation of the RF illumination field, and wherein the RF tags are further configured to perform the responding by way of respective independently selected random radio frequencies and timeslots from respective pre-defined ranges of radio frequencies and timeslots.
-
Citations
21 Claims
-
1. A method of identifying RF tags, the method comprising:
-
issuing a wireless command using a reader, requesting that RF tags identify themselves;
illuminating a plurality of RF tags with a radio frequency field using the reader;
respective RF tags randomly selecting a radio frequency and a timeslot from a plurality of pre-defined radio frequencies and timeslots;
respective RF tags issuing a wireless response to the command, including information identifying the tag, using the selected radio frequency and timeslot;
receiving the wireless responses with the reader; and
issuing wireless acknowledgements from the reader to RF tags that have been successfully identified responsive to the receiving. - View Dependent Claims (2)
-
-
3. A method of identifying RF tags using a reader, the method comprising:
-
issuing a wireless command, using the reader, requesting that RF tags identify themselves;
providing a radio frequency illumination field using the reader;
monitoring a plurality of radio frequencies simultaneously during each of a plurality of consecutive timeslots using the reader; and
receiving a plurality of wireless responses responsive to the command, at different ones of the radio frequencies and timeslots, using the reader. - View Dependent Claims (4, 5, 6, 7, 8)
-
-
9. A radio frequency identification system, comprising:
-
an RF reader configured to issue an RF command requesting that RF tags identify themselves, to provide. a continuous RF illumination field, and to receive responses in any of a plurality of predefined timeslots and frequencies; and
a plurality of RF tags respectively including an identification number;
wherein the plurality of RF tags are configured to respond to the RF command from the RF reader by transmitting their respective identification numbers by way of backscatter modulation of the RF illumination field, and wherein the RF tags are further respectively configured to select a frequency from the plurality of predefined frequencies, to select a timeslot from the plurality of predefined timeslots, and to respond using the selected frequency and timeslot. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16)
-
-
17. An RF tag for use with a reader, the RF tag comprising:
circuitry configured to selectively transmit an RF backscatter modulation communication, including data identifying the RF tag, responsive to an RF discovery command from the reader, wherein the circuitry is further configured to randomly select an IF frequency and a timeslot from a plurality of predetermined possible IF frequencies and timeslots prior to transmitting the RF backscatter modulation communication to the reader. - View Dependent Claims (18, 19)
-
20. A reader for use with an RF tag in an RFID system, the reader comprising:
circuitry configured to selectively transmit a plurality of different types of RF messages including a discovery command having timeframe information, indicating the timeframe during which a response will be processed, and configured to provide an RF illumination field after transmitting a discovery command, wherein the circuitry is further configured to selectively provide a time synchronization signal within the RF illumination field, wherein the circuitry is further configured to simultaneously monitor a plurality of IF frequencies, and wherein the circuitry is further configured to selectively issue an RF acknowledgement message, acknowledging successful identification of an RF tag, responsive to successfully receiving identification data from an RF tag on one of the plurality of IF frequencies by way of backscatter modulation of the RF illumination field. - View Dependent Claims (21)
Specification