Position detection system

{
  "publication_number": "US11378643B2",
  "country": "US",
  "kind": "B2",
  "title": "Position detection system",
  "abstract": "A position detection system 1 identifies position information on the basis of a position signal received from a storage medium 30 P disposed in a placement area where a target item is placed, identifies item information on the basis of an item signal received from a storage medium 30 Q attached to the target item, and associates the position information with the item information and stores the associated information when the item signal is received during a period of time that starts from a time at which the position information is identified and that does not exceed a predetermined length of time.",
  "claims": [
    "1. A position detection system configured to: identify position information based on a position signal received from a first storage medium disposed in a placement area where a target item is placed; identify item information based on an item signal received from a second storage medium fixed to the target item; and associate the position information with the item information and store the associated information when receiving the item signal within a predetermined period of time from a time when the position information was identified, wherein, when not receiving the position signal within the predetermined period of time from a time when the item information was identified, the process of associating the item information with the position information and storing the associated information are not performed, and the receiving the position signal and the receiving the item signal are continued.",
    "2. The position detection system according to claim 1, wherein, when the position signals are received from a plurality of the first storage media disposed in different placement areas and when the ratio of the strength of a certain position signal to the strength of the other position signal exceeds a predetermined ratio, or the ratio of the number of times the certain position signal is read to the number of times the other position signal is read exceeds the predetermined ratio, the position information is identified based on the certain position signal.",
    "3. The position detection system according to claim 1, wherein whether or not to adopt the identified position information as a candidate for position information to be associated with the item information is determined based on one or more identification information of the first storage media recorded in advance corresponding to a receiving position at which the position signal is received.",
    "4. The position detection system according to claim 3, wherein, when identification information of the first storage medium recorded in the position signal received is not included in one or more of the identification information of the first storage media recorded in advance, the position information identified is not adopted.",
    "5. The position detection system according to claim 3, wherein whether or not to adopt the position information as a candidate for position information to be associated with the item information based on the receiving position at which the position signal is received is determined based on a direction in which a directivity of an antenna is maximized when the position signal is received.",
    "6. The position detection system according to claim 1, wherein, when there are one or more other placement areas between two placement areas corresponding to two position information temporally continuously detected, position information of the one or more other placement areas is complemented between the two position information temporally continuously detected."
  ],
  "description_excerpt": "The present invention relates to a position detection system that detects the position of a storage medium.\n\nConventionally, radio frequency identification (RFID) tags are used, for example, by being fixed to products displayed in stores or stored in warehouses. Thus, for example, when a product is sold, a reader reads information such as the product code and the price stored in the tag, whereby the settlement process is performed, and the management of sales performance becomes possible. In addition, there are cases where it is desired to identify the position of an RFID tag, such as a case where it is desired to find a specific product in a store, a warehouse, or the like. Therefore, for example, Patent Document 1 proposes a method for detecting the direction in which an RFID tag is positioned and the distance to the position of the RFID tag by using a change in phase of radio waves. Patent Document 1: Japanese Patent No. 5987187\n\nProblems to be Solved by the Invention The radio waves of an RFID tag are transmitted 300 times per second. In the method for measuring a change in phase described above, the number of RFID tags whose positions can be simultaneously measured is limited. For example, in a store or a distribution base, there is a need for obtaining position information of several hundreds or several thousands of RFID tags, but it is difficult to detect the positions of a large number of RFID tags in a short time by the above-described method. It is an object of the present invention to provide a position detection system capable of detecting the positions of a large number of storage media in a short time.",
  "cpc": [
    "G01S 5/0269",
    "B65G 1/137",
    "B65G 1/1371",
    "G01S 13/0209",
    "G01S 13/75",
    "G01S 13/76",
    "G01S 13/84",
    "G01S 5/02",
    "G01S 5/0284",
    "G01S 5/0295",
    "G06K 17/0022",
    "G06K 7/10",
    "G06K 7/10118",
    "G06K 7/10366",
    "G06K 7/10376",
    "G06Q 10/087"
  ],
  "ipc": [
    "B65G 1/137",
    "G01S 5/02",
    "G06K 7/08",
    "G06K 7/10"
  ],
  "assignees": [
    "RFLOCUS INC"
  ],
  "inventors": [
    "KAMIYA HAJIME"
  ],
  "filing_date": "2020-07-06",
  "publication_date": "2022-07-05",
  "grant_date": "2022-07-05",
  "priority_date": "2019-07-16",
  "application_number": "US-202017298934-A",
  "family_id": "73836074",
  "citations": [
    "JP2005320074A",
    "JP2010089844A",
    "JP2014058403A",
    "JP2017021806A",
    "JP2018078619A",
    "JP5987187B1",
    "KR20090021600A",
    "US2018003812A1",
    "US2018059208A1",
    "US2018307877A1",
    "US2020034583A1",
    "US2021264119A1",
    "US7057511B2",
    "WO2006070563A1",
    "WO2016158105A1"
  ]
}