# US 2014/0197991 A1 · Spatial recognition of rfid tag placement using antenna multiplexing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0197991 A1 - Document ID: US20140197991A1 - Status: Published application - Kind: A1 - Application number: 13/886,987 - Filed: 2013-05-03 - Published: 2014-07-17 - Earliest claimed: 2013-01-15 - Assignees: Disney Enterprises, Inc. - Applicants: Disney Enterprises, Inc. - Inventors: Armen Mkrtchyan; Artaches Haroutunian; Robert Nelson - Web page: https://patentgrep.com/patent/US20140197991A1 ## CPC - G01S 5/0269: {Inferred or constrained positioning, e.g. employing knowledge of the physical or electromagnetic environment, state of motion or other contextual information to infer or constrain a position} - G01S 13/878: {Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector (G01S13/874 takes precedence)} - G06K 7/10356: {using a plurality of antennas, e.g. configurations including means to resolve interference between the plurality of antennas} - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - G06K: GRAPHICAL DATA READING (image or video recognition or understanding G06V); PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS ## Abstract A system to determine the placement of multiple RFID tags uses multiple antennae. The RF communication (or NFC) includes read and/or read/write communication with the RFID tags. ## Claims ### Claim 1 A system to determine spatial placement of one or more radio-frequency identification (RFID) tags using multiplexed antennae for Near Field Communication (NFC), the system comprising: a radio-frequency (RF) reader circuit configured to establish NFC through radio-frequency identification (RFID) with a first radio-frequency identification (RFID) tag; an antenna-selecting module configured to selectively establish electrical coupling to receive information through a first antenna having a first location or through a second antenna having a second location; and a controller configured to determine placement of one or more RFID tags by controlling the antenna-selecting module such that the controller is configured to determine whether the first RFID tag is closer to the first location or the second location. ### Claim 2 (depends on 1) The system of claim 1, wherein the antenna-selecting module includes an antenna multiplexer configured to selectively provide communication with the first antenna and the second antenna. ### Claim 3 (depends on 1) The system of claim 1, wherein the antenna-selecting module includes: a first alternating-current shorting circuit configured to selectively establish electrical coupling for alternating current between an antenna-matching network and the first antenna such that either i) information is received from the first RFID tag through the first antenna, or ii) electrical coupling is selectively shorted; and a second alternating-current shorting circuit configured to selectively establish electrical coupling for alternating current between the antenna-matching network and the second antenna such that either i) information is received from the first RFID tag through the second antenna, or ii) electrical coupling is selectively shorted; wherein the controller is configured to determine placement of one or more RFID tags by controlling the first alternating-current (AC) shorting circuit and the second alternating-current (AC) shorting circuit such that the controller is configured to determine whether the first RFID tag is closer to the first location or the second location. ### Claim 4 (depends on 3) The system of claim 3, further comprising: the first antenna and the second antenna; and the antenna-matching network configured to match electromagnetic properties of the first antenna and the second antenna. ### Claim 5 (depends on 3) The system of claim 3, wherein electrical coupling between the antenna-matching network and the first antenna is selectively shorted by disrupting resonance of the first antenna. ### Claim 6 (depends on 3) The system of claim 3, wherein electrical coupling between the antenna-matching network and the first antenna is selectively shorted by de-tuning the first antenna. ### Claim 7 (depends on 3) The system of claim 3, wherein electrical coupling between the antenna-matching network and the second antenna is selectively shorted by virtue of disrupting resonance of the second antenna and/or de-tuning the second antenna. ### Claim 8 (depends on 3) The system of claim 3, wherein the RF reader circuit is configured to establish NFC by controlling the antenna-matching network. ### Claim 9 (depends on 3) The system of claim 3, wherein the RF reader circuit is configured to establish NFC through one antenna at a time. ### Claim 10 (depends on 3) The system of claim 3, wherein the controller is configured to determine placement of one or more RFID tags by controlling the first AC shorting circuit and the second AC shorting circuit to selectively enable NFC via the antenna-matching network. ### Claim 11 (depends on 3) The system of claim 3, wherein the controller is further configured to control the RF reader circuit to transfer information from the antenna-matching network to the controller. ### Claim 12 (depends on 3) The system of claim 3, wherein the second alternating-current shorting circuit is configured to selectively establish electrical coupling for alternating current between the antenna-matching network and a second antenna having a second location such that either i) information is received from a second RFID tag through the second antenna, or ii) electrical coupling is selectively shorted, wherein the controller is further configured to determine whether the second RFID tag is closer to the first location or the second location. ### Claim 13 (depends on 3) The system of claim 3, further comprising: a third alternating-current shorting circuit configured to selectively establish electrical coupling for alternating current between the antenna-matching network and a third antenna having a third location such that either i) information is received from a first RFID tag through the third antenna, or ii) electrical coupling is selectively shorted, wherein the controller is configured to determine whether the first RFID tag is closer to the first location, the second location, or the third location. ### Claim 14 A computer-implemented method for determining spatial placement of one or more radio-frequency identification (RFID) tags using multiplexed antennae for Near Field Communication (NFC), the method comprising: establishing NFC with a first radio-frequency identification (RFID) tag by controlling an antenna-matching network; selectively establishing electrical coupling such that information is received from the first RFID tag through a first antenna having a first location or a second antenna having a second location; and determining placement of the first RFID tag by selectively enabling NFC through the first antenna and the second antenna, wherein placement determination includes determining whether the first RFID tag is closer to the first location or the second location. ### Claim 15 (depends on 14) The method of claim 14, wherein selectively establishing electrical coupling is accomplished through an antenna multiplexer. ### Claim 16 (depends on 14) The method of claim 14, wherein selectively establishing electrical coupling includes: selectively establishing electrical coupling for alternating current between an antenna-matching network and the first antenna such that information is received from the first RFID tag through the first antenna; and selectively establishing electrical coupling for alternating current between the antenna-matching network and the second antenna such that information is received from the first RFID tag through the second antenna. ### Claim 17 (depends on 16) The method of claim 16, further comprising: matching, by the antenna-matching network, electromagnetic properties of the first antenna and the second antenna. ### Claim 18 (depends on 16) The method of claim 16, wherein selectively establishing electrical coupling for alternating current between the antenna-matching network and the first antenna includes selectively shorting the electrical coupling by disrupting resonance of the first antenna. ### Claim 19 (depends on 16) The method of claim 16, wherein selectively establishing electrical coupling for alternating current between the antenna-matching network and the first antenna includes selectively shorting the electrical coupling by de-tuning the first antenna. ### Claim 20 (depends on 16) The method of claim 16, wherein establishing NFC is performed through one antenna at a time. ### Claim 21 (depends on 16) The method of claim 16, wherein determining placement of the first RFID tag by selectively enabling NFC via the antenna-matching network is accomplished by selectively controlling a first AC shorting circuit such that either i) information is received from the first RFID tag through the first antenna, or ii) electrical coupling for alternating current between the antenna-matching network and the first antenna is selectively shorted. ### Claim 22 (depends on 16) The method of claim 16, further comprising: establishing NFC with a second radio-frequency identification (RFID) tag by controlling the antenna-matching network; selectively establishing electrical coupling for alternating current between the antenna-matching network and the first antenna such that information is received from the second RFID tag through the first antenna; selectively establishing electrical coupling for alternating current between the antenna-matching network and the second antenna such that information is received from the second RFID tag through the second antenna; and determining placement of the second RFID tag by selectively enabling NFC via the antenna-matching network, wherein placement determination includes determining whether the second RFID tag is closer to the first location or the second location. ### Claim 23 (depends on 22) The method of claim 22, wherein establishing NFC with the first RFID tag includes identifying the first RFID tag, and wherein establishing NFC with the second RFID tag includes identifying the second RFID tag. ### Claim 24 (depends on 22) The method of claim 22, further comprising: selectively establishing electrical coupling for alternating current between the antenna-matching network and a third antenna having a third location such that information is received from the first RFID tag through the third antenna; establishing NFC with the second RFID tag by controlling the antenna-matching network; and selectively establishing electrical coupling for alternating current between the antenna-matching network and the third antenna such that information is received from the second RFID tag through the third antenna; wherein placement determination includes determining whether the first RFID tag is closer to the first location, the second location, or the third location, and wherein placement determination includes determining whether the second RFID tag is closer to the first location, the second location, or the third location.