Ultrahigh frequency RFID ceiling type access door identification system and method

Abstract

The invention discloses an ultrahigh-frequency RFID ceiling type access door identification system, which comprises at least two ultrahigh-frequency RFID antennas, an ultrahigh-frequency RFID reader-writer and an access door management terminal, and is characterized in that the ultrahigh-frequency RFID antennas are used for reading data of tags, and the ultrahigh-frequency RFID reader-writer comprises a first behavior identification model and a second behavior identification model; the first behavior identification model is used for identifying whether the tag is static or dynamic according to data input by the ultrahigh frequency RFID reader-writer; and the second behavior identification model is used for further identifying the dynamic tag to obtain the access behavior of the dynamic tag. According to the invention, the in-out behavior of the ultrahigh-frequency RFID tag can be identified only through the tag movement identification algorithm module without depending on peripheral equipment such as an infrared sensor and the like, so that the hardware cost of the system is reduced.

Description

Technical Field

[0001] The present invention relates to the field of ultra-high frequency radio frequency identification (RFID) technology, and more specifically, to an ultra-high frequency RFID ceiling-mounted passage door identification system and method. Background Art

[0002] Common vertical passage doors placed at the entrance of a store are based on high-frequency RFID tags for identification. Due to the inherent properties of high-frequency tags, their radiation range is small, and people must pass through the narrow passage door to correctly identify the tag. In contrast, UHF RFID tags have a large radiation range and can be read within a larger range. Based on the characteristics of UHF RFID tags, there are also many vertical passage doors based on UHF RFID technology on the market.

[0003] However, due to the large radiation range of UHF RFID tags, if there are UHF RFID tags within a certain range near the passage door, there is a risk that these UHF RFID tags will be read. For example, when a person carries files or tools with UHF RFID tags in and out of the warehouse, in addition to the UHF RFID tags carried by the person passing through the passage door, other UHF RFID tags within a certain range near the passage door may also be read. If the passage door uploads all the UHF RFID tag data read to the management system, in this case the management system will not be able to distinguish which are valid UHF RFID tag data that have passed through the passage door and which are invalid UHF RFID tag data that have not passed through the passage door in the environment. In order to solve this problem, the existing vertical passage door usually uses a pair of infrared sensors and other sensor peripherals to judge the entry and exit behavior of personnel, and also adjusts the power of the RFID recognition antenna to make the recognition range as small as possible around the passage door, but it is necessary to ensure that there are no interfering tags within the detection range around the passage door antenna. This technical design solution has high space requirements and poor user experience. Summary of the invention

[0004] The purpose of the present invention is to overcome the various problems mentioned above and provide an ultra-high frequency RFID ceiling-mounted channel door identification system, which does not require the use of sensors or the need to ensure that there are no interfering tags within the detection range around the channel door antenna, and can identify the entry and exit behavior of ultra-high frequency RFID tags.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A UHF RFID ceiling-mounted channel door identification system includes at least two UHF RFID antennas, an UHF RFID reader and a channel door management terminal. The UHF RFID antennas are respectively installed on the tops of the inner and outer sides of the channel door, and are used to read the data of the tag and send the data to the UHF RFID reader. The UHF RFID reader is used to process the data and send the processed data to the channel door management terminal. The UHF RFID reader includes a first behavior recognition model and a second behavior recognition model. The first behavior recognition model is used to recognize whether the tag is static or dynamic according to the data input to it by the UHF RFID reader; the second behavior recognition model is used to further recognize and process the dynamic tag to obtain the entry and exit behavior of the dynamic tag.

[0007] Furthermore, the first behavior recognition model is used to determine whether each tag is dynamic or static based on the relative concentration and changing trend of the antenna state values ​​corresponding to all the tags; and the changing trend of the RSSI value of the ultra-high frequency RFID antenna corresponding to the tag and the relative concentration of the RSSI value in the RSSI value range.

[0008] Furthermore, the second behavior recognition model determines the entry and exit behavior of the tag according to the change trend of the antenna state value and RSSI value corresponding to the dynamic tag during the entire recognition process.

[0009] Furthermore, the RSSI value interval range is 11, namely: 0db, -1~-9db, -10~-19db, -20~-29db, -30~-39db, -40~-49db, -50~-59db, -60~-69db, -70~-79db, -80~-89db, -90~-99db.

[0010] Furthermore, the UHF RFID ceiling-mounted passage door system also includes an alarm module, and the alarm module is controlled by the UHF RFID reader / writer.

[0011] Furthermore, the alarm module is an audible and visual alarm.

[0012] The present invention also provides an ultra-high frequency RFID ceiling-mounted channel door identification method, comprising the following steps:

[0013] Step (1): The UHF RFID antenna starts working to read the tag;

[0014] Step (2): The UHF RFID reader / writer identifies the tag data read by all the UHF RFID antennas in multiple rounds. After each round of identification, the UHF RFID reader / writer records and updates the tag value identified in this round, the antenna number of each tag value in this round of identification, and the RSSI value of the antenna corresponding to each tag value in this round of identification. After all rounds of identification, the UHF RFID reader / writer obtains a list of all tag values, a list of antenna numbers of each tag value in each round of identification, and a list of RSSI values ​​of the antenna corresponding to each tag value in each round of identification.

[0015] Step (3): The first behavior recognition model calculates the relative concentration and change trend of the antenna state values ​​corresponding to all the tags based on the data in step (2); calculates the change trend of the RSSI value of the ultra-high frequency RFID antenna corresponding to the tag, and the relative concentration of the RSSI value in the RSSI value range, so as to identify whether each tag is dynamic or static;

[0016] Step (4): The second behavior recognition model calculates the dynamic tags identified in step (3) to obtain the change trend of the antenna state value and RSSI value corresponding to the tag during the entire identification process, thereby identifying the entry and exit behavior of each dynamic tag.

[0017] Furthermore, it also includes step (5): the UHF RFID reader sends the identified and processed data to the channel door management terminal, and the channel door management terminal is used to display the data and return the access rights of each tag to the UHF RFID reader through the data.

[0018] Furthermore, the method further comprises step (6): when the tag enters or exits illegally, the UHF RFID reader triggers the sound and light alarm to emit an alarm sound.

[0019] Furthermore, the number of rounds in step (2) is 30 rounds.

[0020] Furthermore, the alarm module is an audible and visual alarm.

[0021] Beneficial effects of the present invention:

[0022] 1. The present invention does not need to rely on peripherals such as infrared sensors to identify the entry and exit behavior of UHF RFID tags, but only needs to use the tag movement recognition algorithm module to identify the entry and exit behavior of UHF RFID tags, thereby reducing the system hardware cost;

[0023] 2. The present invention does not need to clean up the interfering tags near the channel door. The interfering tags near the channel door can be filtered out through the tag movement recognition algorithm module, which reduces the requirements of the channel door on the installation environment;

[0024] 3. The passage door of the present invention is installed in a ceiling-mounted manner, which saves valuable ground space resources and improves the user experience;

[0025] 4. The present invention only identifies the entry and exit of people carrying UHF RFID tags, avoiding the identification, uploading and recording of the entry and exit of irrelevant people;

[0026] 5. The present invention does not need to limit the working power of the UHF RFID antenna of the channel door, and it only needs to be adjusted to the maximum power according to the on-site installation environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 : Schematic diagram of the installation structure of the ceiling-mounted passage door from the forward angle.

[0028] Figure 2 : Schematic diagram of the side angle of the ceiling-mounted passage door installation structure.

[0029] Figure 3 : Schematic diagram of label position and movement.

[0030] Figure 4 : Schematic diagram of the proportional distribution of the status values ​​S of tags 1, 2, and 3.

[0031] Figure 5 : Schematic diagram of the change trend of the status value S of tags 1, 2, and 3.

[0032] Figure 6 : Schematic diagram of the changing trend of the state values ​​S of tags 1, 2, and 3 after filtering.

[0033] Figure 7 : Schematic diagram of the RSSI value distribution ratio of tag 1.

[0034] Figure 8 : Schematic diagram of the RSSI value distribution ratio of tag 2.

[0035] Fig. 9 : Schematic diagram of the RSSI value distribution ratio of tag 3.

[0036] Fig.10 : Schematic diagram of the RSSI value change trend of tag 1.

[0037] Fig.11 : Schematic diagram of the change trend of the RSSI value of tag 1 after filtering.

[0038] Fig.12 : Schematic diagram of the RSSI value change trend of tag 2.

[0039] Fig.13 : Schematic diagram of the change trend of the RSSI value of tag 2 after filtering.

[0040] Fig.14 : Schematic diagram of the RSSI value change trend of tag 3.

[0041] Fig.15 : Schematic diagram of the change trend of the RSSI value of tag 3 after filtering.

[0042] Fig.16 : Schematic diagram of the proportional distribution of the state value S of tag 4.

[0043] Fig.17 : Schematic diagram of the change trend of the state value S of tag 4.

[0044] Fig.18 : Schematic diagram of the changing trend of the state value S of tag 4 after filtering.

[0045] Fig.19 : Schematic diagram of the RSSI value distribution ratio of tag 4.

[0046] Fig. 20 : Schematic diagram of the RSSI value change trend of tag 4.

[0047] Fig.21 : Schematic diagram of the change trend of the RSSI value of tag 4 after filtering. DETAILED DESCRIPTION

[0048] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0049] To facilitate the introduction and understanding of the content of this solution, this embodiment only introduces the minimum system of the UHF RFID ceiling-mounted channel door identification system, which includes antenna 1, antenna 2, UHF RFID reader and channel door management terminal. Antenna 1 and antenna 2 are both UHF RFID antennas for identifying tags. Figure 1-2 As shown, antenna 1 and antenna 2 are respectively installed on the top of the inner and outer door frames of the warehouse, the two antennas are connected to the UHF RFID reader, and the UHF reader is connected to the channel door management terminal.

[0050] The UHF RFID reader is used to process the tag data identified by the antenna and run its internal tag movement identification algorithm to generate the final tag identification results and personnel entry and exit behavior results. Finally, the relevant results are uploaded to the channel door management terminal and corresponding processing is performed based on the tag authority results returned by the channel door management terminal.

[0051] The channel door management terminal is used to combine and display tags and personnel entry and exit identification results, verify tag permissions, and collect statistics on related information.

[0052] Preferably, the UHF RFID ceiling-mounted passage door system also includes an audible and visual alarm, and the UHF RFID reader / writer controls the audible and visual alarm.

[0053] When the system of this embodiment is working, the UHF RFID reader simultaneously enables antenna 1 and antenna 2 to read tags, and parses the data to obtain the antenna number of each tag being read. According to the "antenna number", it can be known which antenna has read the tag.

[0054] Assume that there are 4 tags in the scene, namely, tag 1, tag 2, tag 3, and tag 4. Tags 1, 2, and 3 are interference tags in the environment, and tag 4 is a valid tag. The tags in the embodiment of this article are ultra-high frequency tags, which are also applicable to high frequency tags.

[0055] as follows Figure 3 As shown, tag 1 is placed at a position inside the door where it can be read by antenna 1 or antenna 2, tag 2 is placed at a position on the door frame where it can be read by antenna 1 or antenna 2, tag 3 is placed at a position outside the door where it can be read by antenna 1 or antenna 2, and tag 4 is a valid tag that people can hold in and out of the passage door.

[0056] The UHF RFID reader will perform multiple rounds of identification during the entire process of identifying the tag, and in each round of identification, two antennas (antenna 1 and antenna 2) will perform identification simultaneously. In other words, a tag may be read multiple times in multiple rounds of identification, and may be read by different antennas, or may not be read by any antenna.

[0057] After each round of tag identification, the UHF RFID reader will record and update the following content:

[0058] The tag value identified in this round, the antenna number of each tag value in this round of identification (that is, the antenna number of the antenna where the tag is read), and the RSSI value of the antenna corresponding to each tag value in this round of identification.

[0059] After multiple rounds of tag recognition, the UHF RFID reader will obtain the following information:

[0060] A list of all tag values ​​obtained through multiple rounds of identification, a list of antenna numbers for each tag value in each round of identification, and a list of RSSI values ​​for the antennas corresponding to each tag value in each round of identification.

[0061] In this example, there is an antenna inside and outside the door (i.e., antenna 1 and antenna 2). During the identification process of a tag, the corresponding antenna number may be 0 (i.e., not recognized by any antenna), 1 (i.e., only recognized by antenna 1), 2 (i.e., only recognized by antenna 2), or both 1 and 2 (i.e., recognized by both antenna 1 and antenna 2).

[0062] In order to better record and describe "the antenna number of each tag value in this round of identification", this paper proposes an antenna identification state value S, which uses a one-byte state value S to represent multiple antenna combinations. For example, the antenna reading state of tag 1 is S1, the antenna reading state of tag 2 is S2, the antenna reading state of tag 3 is S3, and the antenna reading state of tag 4 is S4.

[0063] The following takes the antenna reading state S1 of tag 1 as an example. The value of S1 is as follows:

[0064] (1) When tag 1 is not read by any antenna, state S1 is recorded as 00;

[0065] (2) When tag 1 is read only by antenna 1, state S1 is recorded as 01;

[0066] (3) When tag 1 is read only by antenna 2, state S1 is recorded as 02;

[0067] (4) When tag 1 is read by both antenna 1 and antenna 2, state S1 is recorded as 03;

[0068] Taking the state S1 of tag 1 as an example, the antenna recognition status of tag 1 and the corresponding state value S1 are shown in Table 1 below:

[0069] Table 1

[0070]

[0071] During the whole process of tag identification, the state value S of any tag must correspond to some of the four states shown in Table 1. Taking tag 1 being identified 15 times as an example, its corresponding state value S1 and RSSI value data are recorded as shown in Table 2 below.

[0072] Table 2

[0073]

[0074]

[0075] According to the relative position of the tag and the antenna, the tags 1, 2, 3, and 4 are divided into two categories:

[0076] (1) Tags with fixed physical positions relative to the antenna, such as tags 1, 2, and 3;

[0077] (2) A tag that moves relative to the physical position of the antenna, such as tag 4.

[0078] For tags with fixed physical positions, the antenna identification status value and the corresponding RSSI value show a relatively fixed trend during the entire process of being read by the UHF RFID reader.

[0079] Take labels 1, 2, and 3 as an example:

[0080] (1) Tag 1 is closer to the recognition range of antenna 1. In most cases, it can only be read by antenna 1. In this scenario, the RSSI value will fluctuate within a small range. In very rare cases, it is not read by any antenna, or is only read by antenna 2, or is read by both antennas 1 and 2.

[0081] (2) Tag 2 is located within the recognition range of antenna 1 and antenna 2. In most cases, it can be read by both antennas 1 and 2. In this scenario, the RSSI value will fluctuate within a small range. In very rare cases, it is not read by any antenna or is only read by antenna 1 or only by antenna 2.

[0082] (3) Tag 3 is closer to the recognition range of antenna 2. In most cases, it can only be read by antenna 2. In this scenario, the RSSI value will fluctuate within a small range. In very rare cases, it is not read by any antenna, or is only read by antenna 1, or is read by both antennas 1 and 2.

[0083] For tags that move physically, during the entire process of being read by the UHF RFID reader, the antenna recognition state value and the corresponding RSSI value show a relative change trend.

[0084] Take the case where tag 4 exits the channel door as an example:

[0085] (1) When tag 4 enters the reading range of antenna 1, it is most likely that it can only be read by antenna 1. During this period, the antenna identification state value S4 is continuously recorded as 01. Since the tag is in a moving state at this time, its distance relative to antenna 1 is changing, and accordingly, the RSSI values ​​corresponding to each antenna are significantly changed.

[0086] (2) When tag 4 continues to move forward and approaches the reading range of antenna 2, it is highly likely that tag 4 will be read by antennas 1 and 2 at the same time. During this period, the antenna identification state value S4 is continuously recorded as 03. Since tag 4 is in a moving state at this time, its distance relative to antenna 1 and antenna 2 is changing, and accordingly, the RSSI values ​​corresponding to each antenna are significantly changed.

[0087] (3) When tag 4 continues to move forward and enters the reading range of antenna 2, it is highly likely that tag 4 will only be read by antenna 2, and during this period, the antenna identification state value S4 is continuously recorded as 02. Since tag 4 is in a moving state at this time, its distance from antenna 2 is changing, and accordingly, the RSSI values ​​corresponding to each antenna are significantly changed.

[0088] (4) When tag 4 continues to move forward and is out of the reading range of antenna 2, it is highly likely that tag 4 will not be read by any antenna. During this period, the antenna identification state value S4 is continuously recorded as 00. Since it is likely that tag 4 will not be read by any antenna in the future, the RSSI value at this time is recorded as 0.

[0089] In this embodiment, when each tag is read for the first time, the UHF RFID reader will initialize the antenna identification round count corresponding to the tag, and each tag will be initialized once the count reaches 30 rounds. It should be noted that the specific number of initializations can be flexibly set according to requirements. The entire tag movement process, i.e., the tag identification process, performs a total of 30 rounds of reading. Taking tag 4 exiting the channel door as an example, the antenna identification state values ​​S corresponding to tags 1, 2, 3, and 4 and the RSSI value data corresponding to each antenna are shown in Table 3 below.

[0090] Table 3

[0091]

[0092]

[0093] From Table 3 above, we can calculate:

[0094] S1:

[0095] The proportion of status value 00 is: 3 / 30 = 10%

[0096] The proportion of status value 01 is: 26 / 30≈86.66%

[0097] The ratio of status value 02 is: 0 / 30=0%

[0098] The proportion of state value 03 is: 1 / 30≈3.33%

[0099] According to the above calculation method, all S1, S2, S3, and S4 data are sorted out to obtain the following Table 4:

[0100] Table 4

[0101]

[0102] In this embodiment, the interval range of the antenna RSSI value is divided into 11, namely: 0db, -1 to -9db, -10 to -19db, -20 to -29db, -30 to -39db, -40 to -49db, -50 to -59db, -60 to -69db, -70 to -79db, -80 to -89db, -90 to -99db. Of course, the division of the interval range can be flexibly set according to needs.

[0103] From Table 3 above, we can calculate the proportion of the RSSI value of tag 1 corresponding to antenna number 1 in each RSSI value range:

[0104] 0db ratio: 3 / 30=10%

[0105] -1db~-9db ratio: 0 / 30=0%

[0106] -10db~-19db ratio: 0 / 30=0%

[0107] -20db~-29db ratio: 0 / 30=0%

[0108] -30db~-39db ratio: 27 / 30=90%

[0109] -40db~-49db ratio: 0 / 30=0%

[0110] -50db~-59db ratio: 0 / 30=0%

[0111] -60db~-69db ratio: 0 / 30=0%

[0112] -70db~-79db ratio: 0 / 30=0%

[0113] -80db~-89db ratio: 0 / 30=0%

[0114] -90db~-99db ratio: 0 / 30=0%

[0115] The ratio of the RSSI value of tag 1 corresponding to antenna number 2 in each RSSI value range:

[0116] 0db ratio: 29 / 30≈96.66%

[0117] -1db~-9db ratio: 0 / 30=0%

[0118] -10db~-19 ratio: 0 / 30=0%

[0119] -20db~-29 ratio: 0 / 30=0%

[0120] -30db~-39 ratio: 0 / 30=0%

[0121] -40db~-49 ratio: 0 / 30=0%

[0122] -50db~-59 ratio: 0 / 30=0%

[0123] -60db~-69 ratio: 1 / 30≈3.33%

[0124] -70db~-79 ratio: 0 / 30=0%

[0125] -80db~-89 ratio: 0 / 30=0%

[0126] -90db~-99 ratio: 0 / 30=0%

[0127] According to the above calculation method, all RSSI1, RSSI2, RSSI3, and RSSI4 data are sorted out as shown in Table 5 below:

[0128] Table 5

[0129]

[0130] Note that in Table 5 above, RSSI1 represents the ratio of the RSSI values ​​of each antenna number corresponding to tag 1 in each RSSI value range; RSSI2 represents the ratio of the RSSI values ​​of each antenna number corresponding to tag 2 in each RSSI value range; RSSI3 represents the ratio of the RSSI values ​​of each antenna number corresponding to tag 3 in each RSSI value range; RSSI4 represents the ratio of the RSSI values ​​of each antenna number corresponding to tag 4 in each RSSI value range.

[0131] Analysis of the antenna state value S and RSSI value corresponding to different tags in the entire identification process shows the following characteristics:

[0132] 1. Fixed-position labels (such as labels 1, 2, and 3):

[0133] (1) Figure 4 As shown, during the entire recognition process, the state value S data is relatively concentrated, with more than 80% of the data concentrated in a certain state value, and the proportion distribution has an obvious peak.

[0134] like Figure 5 As shown, in the 30-round data sequence, the overall state value S changes steadily without obvious step-like change trend.

[0135] The state value S is filtered, such as Figure 6 As shown, a smoother change trend can be obtained.

[0136] (2) As follows Figure 7-9 As shown, during the entire identification process, the range of all RSSI values ​​of each antenna is relatively concentrated, with more than 80% concentrated in a certain signal strength range, and the distribution ratio has an obvious peak.

[0137] In the 30-round data sequence, Fig.10 As shown, the overall RSSI value change trend is relatively stable.

[0138] Filter the RSSI1 data, such as Figure 11-12 As shown, a smoother change trend can be obtained.

[0139] Filter the RSSI2 data, such as Figure 13-14 As shown, a smoother change trend can be obtained.

[0140] Filter the RSSI3 data, such as Fig.15 As shown, a smoother change trend can be obtained.

[0141] 2. Labels with moved positions (such as label 4):

[0142] (1) Fig.16 As shown in the figure, during the entire recognition process, the state value S data is relatively scattered, the distribution of each state value is relatively uniform, and there is no obvious peak in the distribution ratio:

[0143] like Fig.17 As shown in the figure, in the 30-round data sequence, the overall state value S does not change smoothly, but shows a step-by-step change trend:

[0144] like Fig.18 As shown, filtering the state value S can obtain a smoother change trend.

[0145] (2) Fig.19 As shown in the figure, during the entire identification process, the RSSI value range of each antenna is relatively scattered, with no obvious concentration in a certain signal strength range, and the distribution ratio has no obvious peak:

[0146] like Fig. 20 As shown, in the 30 rounds of data sequence, the overall RSSI value trend is not stable:

[0147] like Fig.21 As shown, filtering the RSSI4 data can obtain a smoother change trend.

[0148] Behavior recognition model M1:

[0149] Based on the above analysis, we can conclude that:

[0150] The state value S of all data of static tags is relatively concentrated. In 30 rounds of data, more than 80% are concentrated in a certain state value, and the change trend of state value S is stable. The RSSI value range is relatively concentrated. In 30 rounds of data, more than 80% are concentrated in a certain range, and the change trend of RSSI value is stable.

[0151] The state value S of all data of dynamic tags is relatively dispersed. In the 30 rounds of data, no more than 80% of the state value is in a certain state value, and the state value S shows a step-by-step change trend. The RSSI value range is relatively dispersed. In the 30 rounds of data, no more than 80% of the state value is concentrated in a certain range, and the RSSI value shows a step-by-step change trend.

[0152] Based on this feature, a behavior recognition model M1 for identifying static tags and dynamic tags can be obtained. The UHF RFID reader inputs the real-time recognition tag data of each antenna into the behavior recognition model M1 to obtain the recognition results of static tags and dynamic tags.

[0153] So far, this embodiment has identified the current static tags and dynamic tags, but the entry and exit direction of the tag, that is, the entry and exit direction of the person carrying the tag, is still unclear. Therefore, we need to introduce another behavior recognition model M2, based on the behavior recognition model M1, to identify the entry and exit of the tag (person).

[0154] Behavior recognition model M2:

[0155] Furthermore, the antenna state value S and RSSI value of the entire recognition process of the dynamic tag are analyzed, and the following characteristics are found:

[0156] During the entire recognition process, the state value S of the dynamic tag will show a trend of switching between stable state values ​​as a whole, such as:

[0157] 01——03——02, that is, the tag switches from being read only by antenna 1 to being read by both antennas 1 and 2, and then switches to being read only by antenna 2, indicating that the tag (person) has walked out of the passage door;

[0158] 01-02, that is, the tag switches from being read only by antenna 1 to being read only by antenna 2, indicating that the tag (person) has walked out of the passage door;

[0159] 03-02, that is, the tag switches from being read by antennas 1 and 2 at the same time to being read by antenna 2 only, indicating that the tag (person) has walked out of the passage door;

[0160] 02——03——01, that is, the tag switches from being read only by antenna 2 to being read by antennas 1 and 2 at the same time, and then switches to being read only by antenna 1, indicating that the tag (personnel) enters the passage door;

[0161] 02——01, that is, the tag switches from being read only by antenna 2 to being read only by antenna 1, indicating that the tag (personnel) enters the passage door;

[0162] 03——01, that is, the tag switches from being read by antennas 1 and 2 at the same time to being read by antenna 1 only, indicating that the tag (personnel) enters the passage door;

[0163] The state value that appears three times consecutively is the stable state value.

[0164] During the entire identification process, the RSSI value corresponding to each antenna of the dynamic tag shows an overall trend of changing from weak to strong to weak.

[0165] Based on the above characteristics, a behavior recognition model M2 is derived to identify the entry and exit of tags (people).

[0166] In actual applications, the UHF RFID reader is based on two behavior recognition models M1 and M2. For each tag, it analyzes the current round of recognition results and the previous 30 rounds of recognition results in real time, and finally generates the personnel entry and exit results and the tag entry and exit results.

[0167] When a person walks out of the passage door with tag 4, the UHF RFID reader will identify tags 1, 2, and 3 as interfering static tags and tag 4 as a valid mobile tag in real time based on the above-mentioned recorded results and the behavior recognition model M1. On this basis, the behavior recognition model M2 recognizes the behavior of a person walking out of the passage from the door with tag 4, and uploads the relevant recognition results to the passage door management terminal. The passage door management terminal will query and update the database and return the tag authority verification results to the UHF RFID reader. If there are abnormal entry and exit tags, the UHF RFID reader will control the sound and light alarm to alarm, and display the current recognition result information on the human-computer interaction interface, thus completing the complete passage door entry and exit recognition process. The situation where a person carries a tag into the passage door is handled in the same way as when walking out of the passage door.

[0168] Finally, it should be noted that the above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. Therefore, although the present invention has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that the present invention can still be modified or replaced by equivalents. All technical solutions and improvements that do not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. An ultra-high frequency RFID ceiling-mounted channel door identification system, comprising at least two ultra-high frequency RFID antennas, an ultra-high frequency RFID reader-writer and a channel door management terminal, wherein the ultra-high frequency RFID antennas are respectively installed on the tops of both sides of the channel door, and are used to read the data of the tag and send the data to the ultra-high frequency RFID reader-writer, and the ultra-high frequency RFID reader-writer is used to process the data and send the processed data to the channel door management terminal; characterized in that: The UHF RFID reader / writer includes a first behavior recognition model and a second behavior recognition model; the first behavior recognition model is used to identify whether the tag is static or dynamic based on the data input into it by the UHF RFID reader / writer; the second behavior recognition model is used to further identify the dynamic tag to obtain the entry and exit behavior of the dynamic tag.

2. The UHF RFID ceiling-mounted channel door identification system according to claim 1 is characterized in that: The first behavior recognition model is used to identify the relative concentration and change trend of the antenna state values ​​corresponding to all the tags; The variation trend of the RSSI value of the ultra-high frequency RFID antenna corresponding to the tag and the relative concentration degree of the RSSI value in the RSSI value range are used to determine whether each tag is dynamic or static.

3. The UHF RFID ceiling-mounted channel door identification system according to claim 2 is characterized in that: The second behavior recognition model determines the entry and exit behavior of the tag according to the change trend of the antenna state value and the RSSI value corresponding to the dynamic tag during the entire recognition process.

4. The UHF RFID ceiling-mounted channel door identification system according to claim 2 is characterized in that: The RSSI value interval range is 11, namely: 0db, -1~-9db, -10~-19db, -20~-29db, -30~-39db, -40~-49db, -50~-59db, -60~-69db, -70~-79db, -80~-89db, -90~-99db.

5. The UHF RFID ceiling-mounted channel door identification system according to claim 3 is characterized in that: The UHF RFID ceiling-mounted passage door system also includes an alarm module, and the alarm module is controlled by the UHF RFID reader / writer.

6. The UHF RFID ceiling-mounted channel door identification system according to claim 5 is characterized in that: The alarm module is an audible and visual alarm.

7. A method for identifying an ultra-high frequency RFID ceiling-mounted channel door, characterized in that: The application of the ultra-high frequency RFID ceiling-mounted channel door identification system as described in any one of claims 1 to 6 comprises the following steps: Step (1): The UHF RFID antenna starts working to read the tag; Step (2): The UHF RFID reader / writer identifies the tag data read by all the UHF RFID antennas in multiple rounds. After each round of identification, the UHF RFID reader / writer records and updates the tag value identified in this round, the antenna number of each tag value in this round of identification, and the RSSI value of the antenna corresponding to each tag value in this round of identification. After all rounds of identification, the UHF RFID reader / writer obtains a list of all tag values, a list of antenna numbers of each tag value in each round of identification, and a list of RSSI values ​​of the antenna corresponding to each tag value in each round of identification. Step (3): The first behavior recognition model calculates the relative concentration and change trend of the antenna state values ​​corresponding to all the tags based on the data in step (2); calculates the change trend of the RSSI value of the ultra-high frequency RFID antenna corresponding to the tag, and the relative concentration of the RSSI value in the RSSI value range, so as to identify whether each tag is dynamic or static; Step (4): The second behavior recognition model calculates the dynamic tags identified in step (3) to obtain the change trend of the antenna state value and RSSI value corresponding to the tag during the entire identification process, thereby identifying the entry and exit behavior of each dynamic tag.

8. The UHF RFID ceiling-mounted channel door identification method according to claim 7 is characterized in that: It also includes step (5): the UHF RFID reader sends the identified and processed data to the channel door management terminal, and the channel door management terminal is used to display the data and return the access rights of each tag to the UHF RFID reader through the data.

9. The UHF RFID ceiling-mounted channel door identification method according to claim 8, characterized in that: The step also includes step (6): when the tag enters or exits illegally, the UHF RFID reader triggers the sound and light alarm to emit an alarm sound.

10. The UHF RFID ceiling-mounted channel door identification method according to claim 7, characterized in that: The number of rounds in step (2) is 30 rounds.

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