阅读说明：本技术 无线射频天线的布置方法 (Method for arranging wireless radio frequency antenna ) 是由 王新珩 于 2021-06-04 设计创作，主要内容包括：本发明提供一种无线射频天线的布置方法,包括在货物移动通道上设置多个无线射频天线,每一无线射频天线能沿自身轴线转动,从货物移动通道穿过的每一货物上绑定有一个电子标签,货物与无线射频天线的至少一个可以相对于另一个移动；并且,根据无线射频天线的尺寸与货物移动通道在相对静止方向上的宽度计算布置的无线射频天线的数量,相对静止方向垂直于货物的相对移动方向；根据货物与无线射频天线之间的移动速度计算无线射频天线的转动速度,或者根据无线射频天线的转动速度计算货物与无线射频天线之间的移动速度,以使电子标签在无线射频天线读取范围内的通过时间不少于预设的覆盖时间。本发明能够合理布置无线射频天线,确保电子标签的识别率。(The invention provides a method for arranging wireless radio frequency antennas, which comprises the steps that a plurality of wireless radio frequency antennas are arranged on a cargo moving channel, each wireless radio frequency antenna can rotate along the axis of the wireless radio frequency antenna, an electronic tag is bound on each cargo passing through the cargo moving channel, and at least one of the cargo and the wireless radio frequency antennas can move relative to the other; the number of the arranged wireless radio frequency antennas is calculated according to the size of the wireless radio frequency antennas and the width of the goods moving channel in the relative static direction, and the relative static direction is perpendicular to the relative moving direction of the goods; and calculating the rotating speed of the wireless radio frequency antenna according to the moving speed between the goods and the wireless radio frequency antenna, or calculating the moving speed between the goods and the wireless radio frequency antenna according to the rotating speed of the wireless radio frequency antenna, so that the passing time of the electronic tag in the reading range of the wireless radio frequency antenna is not less than the preset covering time. The invention can reasonably arrange the wireless radio frequency antenna and ensure the identification rate of the electronic tag.)

1. The arrangement method of the wireless radio frequency antenna comprises the following steps:

the goods moving channel is provided with a plurality of wireless radio frequency antennas, each wireless radio frequency antenna can rotate along the axis of the wireless radio frequency antenna, an electronic tag is bound on each goods passing through the goods moving channel, the goods and at least one target wireless radio frequency antenna in the plurality of wireless radio frequency antennas can move relatively, and the antenna surface of the electronic tag is parallel to or tends to be parallel to the target wireless radio frequency antenna;

the method is characterized in that:

calculating the number of the arranged wireless radio frequency antennas according to the size of the wireless radio frequency antennas and the width of the cargo moving channel in a relative static direction, wherein the relative static direction is perpendicular to the relative moving direction of the cargo;

and calculating the rotating speed of the wireless radio frequency antenna according to the moving speed between the goods and the wireless radio frequency antenna, or calculating the moving speed between the goods and the wireless radio frequency antenna according to the rotating speed of the wireless radio frequency antenna, so that the passing time of the electronic tag in the reading range of the wireless radio frequency antenna is not less than the preset covering time.

2. The method of claim 1, wherein:

enabling the passing time of the electronic tag in the reading range of the wireless radio frequency antenna to be not less than the preset covering time comprises the following steps: and enabling the radio frequency antenna to be consistent with or tend to be consistent with the polarization direction of the antenna of the electronic tag at least once in one rotation period.

3. The method of claim 1, wherein:

calculating the number of the arranged wireless radio frequency antennas according to the size of the wireless radio frequency antennas and the width of the cargo moving channel in the relative static direction, wherein the number of the arranged wireless radio frequency antennas comprises the following steps:

and calculating the ratio of the width of the cargo moving channel in the relative static direction to the size of the wireless radio frequency antennas, and determining the number of the wireless radio frequency antennas according to the ratio and the maximum wireless radio frequency antenna channel number of the reader-writer, wherein the number of the wireless radio frequency antennas is not more than the maximum wireless radio frequency antenna channel number of the reader-writer.

4. The method of claim 3, wherein:

if the ratio is not greater than the maximum number of the radio frequency antenna channels of the reader-writer, taking a numerical value not less than the integral of the ratio as the number of the radio frequency antennas.

5. The method of claim 3, wherein:

and if the ratio is larger than the maximum number of the radio frequency antenna channels of the reader-writer, taking the maximum number of the radio frequency antenna channels of the reader-writer as the number of the radio frequency antennas.

6. The method of claim 5, wherein:

if the number of the radio frequency antennas is not larger than the ratio, a plurality of the radio frequency antennas move in the relative static direction to read the data of the electronic tag.

7. The method of claim 6, wherein:

moving a plurality of the radio frequency antennas in the relative stationary direction comprises: the plurality of radio frequency antennas move integrally in the relative stationary direction.

8. The method of claim 7, wherein:

moving a plurality of the radio frequency antennas in the relative stationary direction comprises: the distance of each movement of the plurality of radio frequency antennas is not more than the total width of the plurality of radio frequency antennas in the relative static direction.

9. The method of arranging rf antennas according to any of claims 2 to 8, wherein:

the relative rest directions are more than two;

the sum of the number of the plurality of the radio frequency antennas in the relative static direction is not more than the maximum number of radio frequency antenna channels of the reader-writer.

10. The method of arranging rf antennas according to any of claims 1 to 8, wherein:

the goods moving channel is a flow production line, a plurality of wireless radio frequency antennas are arranged on a bracket of the flow production line, and the goods are transmitted on a conveyor belt; or

The goods removes the passageway and is the door footpath passageway, and is a plurality of wireless radio frequency antenna set up in on the carriage of door footpath passageway, the carriage can be in relative movement direction is upwards slided.

Technical Field

The invention relates to the technical field of wireless radio frequency, in particular to a method for arranging wireless radio frequency antennas of a wireless radio frequency system.

Background

The radio frequency communication system generally includes a radio frequency antenna and an electronic tag which are separated from each other, and the reader communicates with the electronic tag through a radio frequency chip, for example, to transmit data to the electronic tag or read data from the electronic tag. Radio frequency communication has been widely used in various fields, such as production of products, transportation and storage of goods, and the like.

As people demand personalized customized products increasingly, for example, more and more people like to customize personalized clothing, young families customize furniture for new residences, and the like. The personalized customization means that the number of products or parts of a certain specification is very small, even only one product or part is needed, which puts brand new technical requirements and management requirements on workshop manufacturing of a factory, and one feasible technical scheme is to introduce a UHF (ultra high frequency) radio frequency identification technology, namely an RFID technology. The RFID technology referred to herein below is UHF (ultra high frequency) RFID technology. When the RFID technology is applied to a production line, each customized product or its component needs to be bound (e.g., fixed, adhered or embedded by a binding wire) with a unique coded RFID tag, and identification and tracking are performed on a production line, a warehouse or a logistics link of a workshop in a flow line (single piece or multiple pieces) manner or in a batch (tens of pieces or even hundreds of pieces) manner by using an RFID identification system. Generally, management requires a tag identification rate of not less than 99.995%. The existing RFID identification technology and its system have difficulty in satisfying this requirement due to the limitation of production conditions.

The wireless radio frequency communication system mainly comprises an RFID electronic tag, an RFID reader-writer and an RFID antenna. The RFID electronic tag is also called as a radio frequency tag, a transponder and a data carrier and consists of a chip and an antenna, the types of the RFID electronic tag antenna comprise an etching antenna, a PCB (printed Circuit Board) copper-plated antenna, a ceramic antenna and the like, and the etching antenna has the advantages of lower cost and the disadvantage of the worst distance reading effect of the same pad distance; the PCB copper-plated antenna has the advantages of better reading distance and higher cost; the ceramic antenna has the advantage of best performance and the disadvantage of high cost.

At present, an electronic tag is a metal-resistant RFID tag, and is packaged by a special anti-magnetic wave-absorbing material, so that the problem that the electronic tag cannot be attached to a metal surface for use is technically solved, and the electronic tag can be waterproof, acid-proof, alkali-proof, anti-collision and high-temperature-resistant and can be used outdoors. The metal-resistant electronic tag can be attached to metal to obtain good reading performance even if the reading distance is longer than that of the metal-resistant electronic tag in the air. Due to the adoption of a special circuit design, the electronic tag can effectively prevent metal from interfering radio frequency signals, and has the following outstanding performances: the reading distance of the metal paste is farther than the recognition distance of the metal paste.

An RFID reader is a device for reading and writing an electronic tag, and usually requires an RFID antenna to realize communication with the electronic tag, the RFID antenna is also called a reader antenna or a wireless radio frequency antenna, and is used for transmitting radio frequency signals between the electronic tag and the reader, and the commonly used RFID antenna mainly includes a wired polarized antenna and a circularly polarized antenna.

The electronic tag and the RFID reader-writer realize space (non-contact) coupling of radio frequency signals through coupling elements of antennas of the electronic tag and the RFID reader-writer, and energy transfer and data exchange are realized in a coupling channel according to a time sequence relation. When the RFID system is adopted for wireless radio frequency identification, the RFID reader-writer sends out an inquiry signal through the wireless radio frequency antenna, after the electronic tag receives the inquiry signal, part of energy of the inquiry signal is used for a working power supply of an internal chip of the electronic tag, and the other part of the inquiry signal is modulated by an internal circuit of the electronic tag and then returns to the RFID reader-writer.

Therefore, whether the RFID reader can identify the electronic tag depends on whether the energy obtained by the antenna of the electronic tag is enough to activate the chip and the circuit inside the electronic tag. The larger the area of the electronic tag is, the larger the size of the electronic tag is, the stronger the energy obtaining capability is; the larger the distance between the RFID antenna and the antenna of the electronic tag, the smaller the energy obtained by the antenna of the electronic tag.

For a linearly polarized RFID antenna, when the polarization direction of the antenna of the electronic tag is consistent with the linear polarization direction of the RFID antenna, the induced signal is maximum, the identification distance of the RFID antenna is farthest at the moment, and the identification sensitivity is high; when the polarization direction of the antenna of the electronic tag deviates more and more from the linear polarization direction, the smaller the induced signal is, the smaller the identification distance at the moment is, and the identification sensitivity is deteriorated; when the polarization direction of the antenna of the electronic tag is orthogonal to the linear polarization direction, the induced signal is zero, and the electronic tag cannot be identified.

For an ideal circularly polarized RFID antenna, the induced signals are the same regardless of the polarization direction of the antenna of the electronic tag, and there is no difference, so that the circularly polarized RFID antenna is used in most applications. However, the actually produced circularly polarized RFID antenna cannot be in an ideal state, and important indexes such as lobe widths of different models also differ. The larger the lobe width is, the lower the requirement on the consistency of the polarization directions of the antenna of the electronic tag and the RFID antenna is, and the smaller the identification distance is; the smaller the lobe width is, the higher the requirement on the consistency of the polarization directions of the antenna of the electronic tag and the RFID antenna is, and the larger the identification distance is.

A line production wireless radio frequency identification system applied to a production line of a workshop, a warehouse, a logistics link and the like usually adopts a fixed RFID antenna. On one hand, due to the limitation of production conditions and the like, some electronic tags are required to be waterproof, corrosion-resistant and high-temperature resistant, some electronic tags are required to be small-sized, and the identification distance cannot be too small, and the like. On the other hand, the polarization directions of the antennas of one electronic tag bound on one piece of product or on one part of the product are random, and the polarization directions of each electronic tag antenna and the polarization directions of the RFID antennas are not consistent or tend to be consistent, so that the electronic tags are easy to miss reading in the case. On the other hand, the line production of the production line means that the identification time of each electronic tag is limited, and tens or hundreds of electronic tags need to be identified in a limited time slice, which brings extremely high requirements on the identification of the electronic tags. The factors of the three aspects are superposed, so that the existing RFID identification technology and the system thereof cannot meet the identification rate requirement of not less than 99.995% required by production management.

How to reasonably arrange the radio frequency antenna on the door diameter of a production line and a warehouse will influence the identification rate of the electronic tag. For example, chinese utility model patent publication No. CN207993048U discloses a high-efficiency production line system, which is provided with a plurality of wireless rf antennas, the plurality of wireless rf antennas are located on one side of the conveyer belt, and electronic tags are bound on the goods conveyed on the conveyer belt. However, in this scheme, only two radio frequency antennas are arranged in the flowing direction of the conveyor belt to increase the identification rate of the electronic tag, but the rationality of the arrangement of the radio frequency antennas is not considered, that is, the influence of a plurality of factors such as the coverage area of the radio frequency antennas and the flow rate of the production line on the identification rate of the electronic tag is not considered, so that the radio frequency antennas cannot be reasonably arranged, which often results in a low identification rate of the electronic tag, or a large number of radio frequency antennas need to be arranged to increase the identification rate, which results in a high production cost of the production line system, and finally results in a high production cost of the product.

Disclosure of Invention

The invention aims to provide a method for arranging a radio frequency antenna, which can meet the requirement of the identification rate of an electronic tag and has lower production cost.

In order to achieve the purpose of the invention, the arrangement method of the wireless radio frequency antennas comprises the steps that a plurality of wireless radio frequency antennas are arranged on a cargo moving channel, each wireless radio frequency antenna can rotate along the axis of the wireless radio frequency antenna, an electronic tag is bound on each cargo passing through the cargo moving channel, the electronic tag on any one cargo and at least one target wireless radio frequency antenna in the plurality of wireless radio frequency antennas can move relatively, and the antenna surface of the electronic tag and the target wireless radio frequency antenna are parallel or tend to be parallel; the number of the arranged wireless radio frequency antennas is calculated according to the size of the wireless radio frequency antennas and the width of the goods moving channel in the relative static direction, and the relative static direction is perpendicular to the relative moving direction of the goods; and calculating the rotating speed of the wireless radio frequency antenna according to the moving speed between the goods and the wireless radio frequency antenna, or calculating the moving speed between the goods and the wireless radio frequency antenna according to the rotating speed of the wireless radio frequency antenna, so that the passing time of the electronic tag in the reading range of the wireless radio frequency antenna is not less than the preset covering time.

According to the scheme, the number of the wireless radio frequency antennas to be arranged is determined according to multiple factors such as the relative moving speed between the goods and the wireless radio frequency antennas, the rotating speed of the wireless radio frequency antennas and the size of the wireless radio frequency antennas, and the wireless radio frequency antennas are arranged in the non-flow velocity direction, so that the positions of the wireless radio frequency antennas can be determined, on one hand, the electronic tags on the goods can be identified within enough time, on the other hand, the electronic tags can be read by the wireless radio frequency antennas with the minimum number, and the production cost of a production line, a warehouse and the like is reduced.

One preferable scheme is that the step of enabling the passing time of the electronic tag in the reading range of the radio frequency antenna to be not less than the preset coverage time comprises the following steps: the radio frequency antenna is enabled to be consistent with or tend to be consistent with the polarization direction of the antenna of the electronic tag at least once in one rotation period.

Because the polarization direction of the radio frequency antenna is consistent with the polarization direction of the antenna of the electronic tag or tends to be consistent for at least one time every rotation period of the radio frequency antenna, the radio frequency antenna can be ensured to correctly read the signal sent by the electronic tag, the identification rate of the electronic tag can be effectively improved, and a radio frequency system on a production line has higher identification sensitivity.

Further, the step of calculating the number of the arranged wireless radio frequency antennas according to the size of the wireless radio frequency antennas and the width of the goods moving channel in the relative static direction comprises the following steps: and calculating the ratio of the width of the cargo moving channel in the relative static direction to the size of the wireless radio frequency antennas, and determining the number of the wireless radio frequency antennas according to the ratio and the maximum wireless radio frequency antenna channel number of the reader-writer, wherein the number of the wireless radio frequency antennas is not more than the maximum wireless radio frequency antenna channel number of the reader-writer.

Due to the fact that the number of the wireless radio frequency antenna channels of the reader-writer is limited, on one hand, the reader-writer needs to be ensured to be capable of reading signals transmitted by all the wireless radio frequency antennas, on the other hand, the reader-writer needs to be ensured to be capable of completely covering the goods moving channel in the relative static direction, and therefore the electronic tag is prevented from being read in an omission mode. The method of the invention can ensure the identification rate of the electronic tag to the maximum extent and reduce the production cost.

In a further aspect, if the ratio is not greater than the maximum number of RF antenna channels of the reader/writer, the number of RF antennas is determined as a value not less than the integral of the ratio.

Therefore, reasonable radio frequency antennas can be arranged in the range of the radio frequency antennas which can be read by the reader-writer so as to ensure the identification rate of the electronic tags.

In a further aspect, if the ratio is greater than the maximum number of radio frequency antenna channels of the reader/writer, the maximum number of radio frequency antenna channels of the reader/writer is used as the number of radio frequency antennas.

Therefore, the invention can avoid the excessive number of the arranged wireless radio frequency antennas and can ensure the identification rate of the electronic tag.

Preferably, if the number of the radio frequency antennas is not greater than the ratio, the plurality of radio frequency antennas move in a relatively static direction to read the data of the electronic tag, and specifically, the plurality of radio frequency antennas move integrally in the relatively static direction.

Therefore, in the relative static direction, if the plurality of radio frequency antennas can not completely cover the goods moving channel, the data of the plurality of electronic tags can be read in a mode of moving the plurality of radio frequency antennas integrally and moving back and forth in the flow rate direction, and the problem of the identification rate of the electronic tags can be solved.

Further, the moving the plurality of radio frequency antennas in the relative stationary direction comprises: the distance of each movement of the plurality of radio frequency antennas is not more than the total width of the plurality of radio frequency antennas in the relative static direction.

Therefore, the invention can avoid the overlarge distance of each movement of the plurality of wireless radio frequency antennas and can ensure the identification rate of the electronic tag.

More preferably, the relative rest directions are more than two; the sum of the number of the wireless radio frequency antennas in the relative static directions is not more than the maximum wireless radio frequency antenna channel number of the reader-writer.

Therefore, the radio frequency antennas are arranged in a plurality of different relative static directions, and can be identified by at least one radio frequency antenna regardless of the orientation of the electronic tag, so that the identification rate of the electronic tag is ensured.

According to a further scheme, the goods moving channel is a flow production line, a plurality of wireless radio frequency antennas are arranged on a support of the flow production line, and goods are transmitted on a conveying belt; or the goods moving passage is a door diameter passage, the plurality of radio frequency antennas are arranged on a sliding frame of the door diameter passage, and the sliding frame can slide in the relative moving direction.

Therefore, the wireless radio frequency antennas can be reasonably arranged according to the door diameters of the flow production line or the warehouse, so that the wireless radio frequency antennas can accurately identify the electronic tags on the goods flowing through, and the production is smoothly carried out.

Drawings

Fig. 1 is a schematic structural view of a flow line production line to which a first embodiment of the present invention is applied.

Fig. 2 is a flowchart of a first embodiment of the method for arranging the rf antennas according to the present invention.

Fig. 3 is a flow chart of a first antenna rotation manner in a first embodiment of the method for arranging a radio frequency antenna according to the present invention.

Fig. 4 is a flowchart of a second antenna rotation manner in the first embodiment of the method for arranging rf antennas according to the present invention.

Fig. 5 is a schematic structural view of a door diameter passage to which a second embodiment of the present invention is applied.

Fig. 6 is a flowchart of a second embodiment of the method for arranging rf antennas according to the present invention.

Fig. 7 is a flowchart of controlling the movement of the rf antenna according to the second embodiment of the method for arranging the rf antenna of the present invention.

The invention is further explained with reference to the drawings and the embodiments.

Detailed Description

The arrangement method of the wireless radio frequency antenna is used for arranging the wireless radio frequency antenna arranged on the flow production line or the door aperture, ensures that the electronic tags carried by the goods flowing through the flow production line or the door aperture can be accurately identified, and provides convenience for production. On the one hand, it is necessary to ensure the identification accuracy of a plurality of electronic tags, and on the other hand, the radio frequency antennas are arranged in the minimum number to reduce the production cost. The present invention will be described in detail below by taking a flow line type production line and a gate diameter as examples.

Method for arranging radio frequency antennas first embodiment:

the present embodiment is applied to a flow line, and referring to fig. 1, a flow line 10 is provided with a conveyor belt 11, and a plurality of goods 12 are placed on the conveyor belt 11 and transported by the conveyor belt 11. In this embodiment, each item 12 is bound with an electronic tag, and preferably, each electronic tag has a unique ID code. As can be seen from fig. 1, the moving direction of the conveyor belt 11 is the direction along the X-axis, and therefore, the X-axis direction is also the flow direction of the conveyor belt 11.

In order to detect the ID code of each electronic tag, a plurality of rf antennas are disposed on the production line, preferably, brackets 20 are disposed on both sides of the conveyor belt 11, for example, a bracket 20 is disposed on both sides of the conveyor belt 11 in the Y-axis direction, each bracket 20 includes a column 21, a cross bar 22 is disposed on an upper end of the column 21, an rf antenna support frame 23 is disposed below the cross bar 22, and an rf antenna is disposed on a lower surface of each rf antenna support frame 23. In addition, the radio frequency antenna support frame 23 is driven by the motor 24 to rotate, so that the radio frequency antenna can rotate along the axis of the radio frequency antenna.

As can be seen from fig. 1, four rf antenna support frames 23 are provided above the conveyor belt 11, and therefore, above the conveyor belt 11, data of the electronic tags on the conveyor belt 11 are read using the four rf antennas. The four wireless radio frequency antennas are divided into two groups, each group comprises two wireless radio frequency antennas arranged along the Y-axis direction, and the central lines of the wireless radio frequency antennas in one group are aligned with the spaced central lines of the wireless radio frequency antennas in the other group. Of course, if the width of the interface of the conveyor belt 11 is less than 2 times the width of the square rf antenna, only one rf antenna per set is needed.

However, since the goods 12 may be placed on the conveyor belt 11 in disorder, the antenna direction of the electronic tag on the goods 12 is uncertain, and if the antenna of the electronic tag is located just above the XoZ plane, the data of the electronic tag cannot be read by the radio frequency antenna located right above the conveyor belt 11. Therefore, the left side and the right side of the conveyor belt 11 along the Y-axis direction are respectively provided with a wireless radio frequency antenna support frame 25, and one side of each wireless radio frequency antenna support frame 25, which is close to the conveyor belt 11, is provided with a wireless radio frequency antenna so as to read data of the electronic tag on the conveyor belt 11. Similarly, each rf antenna supporting frame 25 is driven by a motor 26 and enables the electronic tag to rotate around its own axis. Of course, if the width of the conveyor belt 11 in the Y-axis direction is greater than the read distance of the electronic tag, the rf antennas are disposed on both sides of the conveyor belt 11, otherwise, only one side of the conveyor belt needs to be disposed with the rf antenna.

In this way, no matter how the electronic tag of the cargo 12 is placed, at least one of the plurality of radio frequency antennas is parallel or nearly parallel to the antenna surface of the electronic tag, and the radio frequency antenna parallel or nearly parallel to the antenna surface of the electronic tag is the target radio frequency antenna. The trend of parallelism referred to herein is the case where the angle between the antenna face of the electronic tag antenna and the target radio frequency antenna does not exceed the lobe width of the radio frequency antenna (45 ° in this embodiment).

A reader/writer 29 is further disposed on the top of the conveyor belt 11, the reader/writer 29 can receive signals transmitted by a plurality of wireless rf antennas, and preferably, the reader/writer 29 has the maximum number of channels of wireless rf antennas that can be received, that is, data of wireless rf antennas that the reader/writer 29 can simultaneously communicate is limited. For this reason, the sum of the number of the radio antennas provided at the periphery of the conveyor belt 11 should not exceed the maximum number of radio antenna channels of the reader/writer 29.

Further, a display 28 is provided on one of the stands 20, and information of the plurality of electronic tags read by the reader/writer 29 can be displayed on the display 28, and the display 28 can also display information such as the moving speed of the conveyor belt 11 and the transfer speeds of the plurality of radio frequency antennas.

In this embodiment, the two brackets 20 are both fixed above the conveyor belt 11, and each of the rf antennas is not movable along the X-axis direction, and since the goods 12 can move along with the conveyor belt 11, the electronic tag on the goods 12 moves along the X-axis direction relative to the conveyor belt 11. The present embodiment defines the X-axis direction as the flow direction of the conveyor belt 11, that is, the moving direction of the goods 12 and the electronic tags. Accordingly, since the electronic tag is immovable with respect to the Y-axis direction and the Z-axis direction, both the Y-axis direction and the Z-axis direction are relatively stationary directions.

It can be seen that the relative rest directions of the present embodiment include the Y-axis direction and the Z-axis direction, i.e., the rest directions are two. Of course, it should be noted that if the goods 12 on the conveyor belt 11 are placed in order and the antenna of each electronic tag is parallel to the plane XoY, the rf antenna may be disposed only on the top surface of the conveyor belt 11, and there is no need to dispose the rf antennas on both sides in the Y-axis direction, and there is only one rf antenna in the Y-axis direction.

The process of disposing the rf antenna on the water line is described with reference to fig. 2. In this embodiment, since the moving speed of the conveyor belt 11 of the flow production line is fixed, that is, the flow rate of the electronic tag is fixed, and the size of the selected wireless rf antenna is also fixed, the number and the rotation speed of the used wireless rf antennas need to be determined according to the flow rate of the electronic tag and the size of the wireless rf antenna, and the arrangement positions of the plurality of wireless rf antennas are further determined, so as to ensure that the electronic tag at any point on the conveyor belt 11 can be covered by the wireless rf antenna for a sufficiently long time T_coverSo that at least at a minimum effective reading time T_minvalueIn the chip, the polarization directions of the antenna of the electronic tag and the radio frequency antenna are consistent or tend to be consistent, so that the electronic tag can be correctly identified and read. Wherein the minimum effective reading time T_minvalueIs a parameter predetermined according to the parameter of each electronic tag.

The present embodiment first performs step S21 to determine the flow velocity V of the conveyor belt 11 of the production line_flowAnd determining the dimension of the radio frequency antenna, in particular the dimension of the radio frequency antenna in the direction of flow, i.e. the dimension Y in the direction of the X axis_flowPreferably, the dimension Y of the radio frequency antenna_flowThe following requirements should be met: t is_cover＝Y_flow/V_flow>n/f_readerWherein f is_readerFor the reading frequency of the reader/writer 29, the minimum effective reading time T_minvalue＝n/f_reader，n＝180/L_obewidth，L_obewidthThe lobe width of the radio frequency antenna.

Then, step S22 is executed to calculate the ratio of the width of the production line in the non-flow direction to the width of the rf antenna. The non-flow direction in this embodiment is a relatively static direction, and is taken as an example of a radio frequency antenna disposed on the top of the conveyor belt 11, the non-flow direction is along the Y-axis, and it is assumed that the width of the production line along the Y-axis is W_YThe width of the radio frequency antenna along the Y-axis direction is W_antThen the value n calculated in step S22_YThe following formula can be used for calculation: n is_YRounding (W)_Y/W_ant) +1, that is, at the top of the production line, the number of the radio frequency antennas arranged along the Y-axis direction is the ratio of the width of the production line in the Y-axis direction to the width of the radio frequency antennas, which is rounded, and then added by 1, so that the number of the radio frequency antennas is greater than the ratio.

Similarly, if the rf antennas are disposed on both sides of the conveyor belt 11 in the Y-axis direction, the non-flow velocity direction is the Z-axis direction, and the number n of the rf antennas on both the left and right sides of the conveyor belt 11_ZRounding (W)_Z/W_ant) +1, wherein W_ZIs the maximum height, W, of the goods 12 on the conveyor belt 11 in the Z-axis direction_antIs the width of the radio frequency antenna along the Z-axis direction on the left and right sides of the conveyor belt 11.

Then, step S23 is executed to determine the maximum number N of channels of the wireless rf antennas of the reader/writer 29, that is, the upper limit of the number of wireless rf antennas that can be received by the reader/writer 29, where the sum of the wireless rf antennas disposed on the top, the left side, and the right side of the conveyor belt 11 needs to be less than or equal to the maximum number N of channels of the wireless rf antennas of the reader/writer 29, otherwise, the reader/writer 29 may not completely read the data of all the wireless rf antennas.

Next, step S24 is executed to determine the number of arranged rf antennas according to the results of the calculation in steps S22 and S23, specifically, if the sum of the numbers of rf antennas arranged on the top and left and right sides of the conveyor belt 11 calculated in step S22 does not exceed the maximum number N of rf antenna channels of the reader/writer 29, then a plurality of rf antennas are arranged according to the number of rf antennas calculated in step S22, and if the sum of the numbers of rf antennas arranged on the top and left and right sides of the conveyor belt 11 calculated in step S22 exceeds the maximum number N of rf antenna channels of the reader/writer 29, then the number of arranged rf antennas is N, that is, the maximum number of rf antenna channels of the reader/writer 29. And the plurality of radio frequency antennas are not overlapped with each other in the non-flow velocity direction.

Finally, step S25 is executed to determine the rotation speed of the rf antennas according to the number of the rf antennas. Taking the wireless rf antenna disposed on the top of the conveyor belt 11 as an example, assuming that the distance between the wireless rf antenna and the conveyor belt 11 is 1000 mm, the electronic tag selects a metal-resistant UHF electronic tag with a diameter of Φ 5 mm × H4 mm, the selection frequency range of the wireless rf antenna is 902MHz to 928MHz, and the lobe widths are respectively in the horizontal direction: 45 °, vertical direction: 45 degrees, the coverage size of the radio frequency antenna is 400 millimeters and 400 millimeters in the X-axis direction and the Y-axis direction respectively, and preferably, a circularly polarized radio frequency antenna is selected. And, the reading frequency f of the reader/writer_reader40 times/sec. Therefore, the antenna coverage time T of the electronic tag can be calculated_coverThe dimension of the radio frequency antenna flow coverage is 400 mm/(10 m/min of the production line flow speed), 400/(10 × 1000/(60 × 1000)) ms, 2400 ms.

Before the rotation speed of the radio frequency antenna is determined, the rotation mode of the radio frequency antenna is also determined. In this embodiment, the rf antenna has two different rotation modes, which are described below with reference to fig. 3 and 4.

Referring to fig. 3, the first rotation mode of the rf antenna first executes step S31, the reader/writer 29 starts the process of reading the data of the electronic tag, and then executes the processIn step S32, the rf antenna stops rotating for a first time. Then, step S33 is executed, the rf antenna rotates forward at a first rotation speed for a first angle, for example, 45 °, step S34 is executed, it is determined whether the maximum angle, for example, 360 °, is reached, if the maximum angle is not reached, the process returns to step S32, if the maximum angle is reached, the process returns to step S35, and the rotation is stopped for a first time T_stopAnd reading the data of the electronic tag in the first time. Then, step S36 is executed, the wireless rf antenna reverses the first angle at the first rotation speed, for example, 45 °, step S37 is executed, it is determined whether the maximum angle, that is, 360 °, is reached, if the maximum angle is not reached, step S35 is executed again, if the maximum angle is reached, step S38 is executed, all read data of the wireless rf antenna are recorded, for example, all read ID codes of the wireless rf antenna are recorded, step S39 is executed, it is determined whether the production line stops operating, if the production line does not stop operating, step S32 is executed again, the wireless rf antenna continues to rotate, if the production line stops operating, step S40 is executed, and the process of reading the electronic tag data is ended.

It can be seen that if the rf antenna is rotated in the first manner, the step S25 needs to calculate the first rotation speed and the first time when the rf antenna stops rotating. In this embodiment, the radio frequency antenna needs to be consistent with or tend to be consistent with the polarization direction of the antenna of the electronic tag at least once in one rotation period, and since one rotation period of the radio frequency antenna is 360 °, the rotation is stopped for the first time and the data of the electronic tag is read every 45 ° of rotation, so that one rotation period of the radio frequency antenna does not exceed the antenna coverage time T of the electronic tag_coverI.e., 2400 milliseconds. For example, the first rotation speed is 200 rpm for a first time T_stop200 ms, so that the time required for one rotation period of the radio frequency antenna is 1605 ms, which does not exceed the antenna coverage time T of the electronic tag_cover. Moreover, since the lobe width of the radio frequency antenna is 45 degrees, after the antenna rotates 45 degrees every time and stops rotating a time slice, the antenna of the electronic tag and the radio frequency antenna always appear once after rotating 4 timesThe polarization direction of the antenna is or tends to be consistent, and the method can ensure that each electronic tag can be correctly identified.

Further, the reader/writer 29 reads data of each electronic tag in parallel while the radio frequency antenna is rotating and stopping. Therefore, the rotation of the radio frequency antenna is performed in parallel with the reading of the electronic tag data by the reader/writer 29.

Referring to fig. 4, the second rotation method of the rf antenna firstly performs step S41, the reader starts the process of reading the electronic tag data, and then performs step S42, and rotates the rfid antenna forward by a second rotation speed by a second angle, for example, the second angle is 360 °. Then, step S43 is executed, and the radio frequency antenna stops rotating for a second time.

Next, step S44 is executed to reverse the second angle at the second rotation speed, for example, the second angle is 360 °. Then, step S45 is executed, and the radio frequency antenna stops rotating for a second time. Step S46 is executed to record all the read data of the rf antenna, for example, all the read ID codes of the rf antenna. Then, step S47 is executed to determine whether the production line is stopped, if not, the process returns to step S42, and if the production line is stopped, step S48 is executed to end the process of reading the electronic tag data.

It can be seen that if the rf antenna is rotated in two ways, step S25 needs to calculate the second rotation speed and the second time for the rf antenna to stop rotating. In this embodiment, the radio frequency antenna needs to be consistent with or tend to be consistent with the polarization direction of the antenna of the electronic tag at least once in one rotation period, and since one rotation period of the radio frequency antenna is 360 ° and the rotation needs to be stopped for the second time after one rotation period, the second time may be set to 400 milliseconds, and the second rotation speed of the radio frequency antenna is 0.625 revolutions per second, that is, each rotation time is 1600 milliseconds. Thus, the time required for one rotation period of the radio frequency antenna is 2000 milliseconds, and the time does not exceed the antenna coverage time T of the electronic tag_cover. The second rotation method is the same as the first rotation method of the wireless radio frequency antennaIn the formula, the reader/writer 29 reads the data of each electronic tag in parallel while the radio frequency antenna rotates and stops rotating, that is, the rotation of the radio frequency antenna and the reading of the data of the electronic tag by the reader/writer 29 are executed in parallel.

It can be seen that, this embodiment can ensure that the electronic tags of all goods 12 on the conveyer belt 11 can be correctly identified by the wireless radio frequency antenna through the position of rationally arranging a plurality of wireless radio frequency antennas, and ensure that the identification rate to the electronic tags meets the requirements.

Method for arranging radio frequency antennas second embodiment:

in the present embodiment, for example, the door diameter of the warehouse, referring to fig. 5, a sliding frame 50 is disposed at the front end of the door diameter passage 40 of the warehouse, the sliding frame 50 includes two guide rails 51 extending along the direction of the door diameter passage 40, the sliding frame 50 includes a plurality of upright posts 52, two cross bars 53 are disposed on the top of the sliding frame 50, a plurality of rf antenna supports 54 are disposed below the cross bars 53, and one rf antenna is disposed on the lower surface of each rf antenna support 54. In addition, the radio frequency antenna support 54 is rotated by the motor 55, so that the radio frequency antenna can rotate along its own axis.

In this embodiment, the door diameter passage 40 constitutes a cargo moving passage, and thus the cargo moving passage extends in the X-axis direction. Goods 45 entering and exiting the warehouse are pushed to the warehouse door diameter passage by the trolley 42, and each goods 45 is bound with an electronic tag, preferably, each electronic tag has a unique ID code. As can be seen from fig. 5, four rf antenna supports 54 are provided on the top of the carriage 50, so that the data of the electronic tag on the cargo 45 is read using the four rf antennas on the top of the carriage 50. The four wireless radio frequency antennas are divided into two groups, each group comprises two wireless radio frequency antennas arranged along the Y-axis direction, and the central lines of the wireless radio frequency antennas in one group are aligned with the spaced central lines of the wireless radio frequency antennas in the other group. Of course, if the width of the door diameter passage 40 is less than twice the width of the square rf antenna, only one rf antenna is needed for each group.

However, since the cargo 45 passing through the door diameter passage 40 may be placed out of order, the antenna direction of the electronic tag on the cargo 45 is uncertain, and if the antenna of the electronic tag is located just above the XoZ plane, the rfid antenna located directly above the sliding frame 50 cannot read the data of the electronic tag. Therefore, one or more radio frequency antenna support frames 61 are respectively arranged on the left side and the right side of the sliding frame 50 along the Y-axis direction, the radio frequency antenna support frames 61 are supported by the cross bar 60, and one radio frequency antenna is arranged on one side of each radio frequency antenna support frame 61 close to the door diameter passage 40, so that data of the electronic tag of the goods 45 can be read conveniently. Similarly, each rf antenna supporting frame 61 is driven by a motor and enables the electronic tag to rotate around its own axis. Of course, if the width of the door diameter channel 40 in the Y-axis direction is greater than the read distance of the electronic tag, the rf antennas are disposed on both sides of the door diameter channel 40, otherwise, only one side of the door diameter channel needs to be disposed with the rf antenna.

A reader-writer 56 is further disposed on the top of the carriage 50, and the reader-writer 56 can receive signals transmitted by a plurality of radio frequency antennas, and preferably, the reader-writer 56 has the maximum number of channels of the radio frequency antennas that can be received, that is, data of the radio frequency antennas that the reader-writer 56 can simultaneously communicate is limited. For this reason, the sum of the number of RF antennas disposed around the door diameter channel 40 should not exceed the maximum number of RF antenna channels of the reader/writer 56. Further, a display 64 is provided on the carriage 50, and information on the plurality of electronic tags read by the reader/writer 56 can be displayed on the display 64.

In this embodiment, the sliding rack 50 can reciprocate along the two guide rails 51 in the X-axis direction, so that before the goods 45 enter and exit the warehouse, the goods 45 need to stay below the sliding rack 50 for a period of time, and the data of the electronic tag on the goods 45 is read by the plurality of radio frequency antennas through the movement of the sliding rack 50 in the X-axis direction. Therefore, in this embodiment, the electronic tag is stationary, and the plurality of rf antennas move in the X-axis direction relative to the electronic tag, so the flow direction of this embodiment is the X-axis direction, that is, the moving direction of the rf antennas, and the Y-axis direction and the Z-axis direction are both relative stationary directions.

Of course, if the goods 45 passing through the door diameter passage 40 are placed in order and the antenna of each tag is parallel to the XoY plane, the rf antenna can be disposed only on the top surface of the sliding frame 50, and there is no need to dispose the rf antennas on both sides of the Y-axis direction, and there is only one rf antenna in the stationary direction.

The following describes a procedure for disposing the rf antenna on the door path channel with reference to fig. 6. In this embodiment, the rotation speed of the rf antenna may be preset, and the size of the used rf antenna is set, that is, the rotation speed and the size of the rf antenna are fixed, but the moving speed of the carriage may be changed. Therefore, the moving speed, i.e. the flow speed, of the radio frequency antenna relative to the electronic tag needs to be calculated according to the rotation speed and the flow direction size of the radio frequency antenna, so as to ensure that the electronic tag at any point in the door diameter passage 40 can be covered by the radio frequency antenna for a sufficient time T_coverSo that at least at a minimum effective reading time T_minvalueIn the chip, the polarization directions of the antenna of the electronic tag and the radio frequency antenna are consistent or tend to be consistent, so that the electronic tag can be correctly identified and read.

The embodiment first executes step S61 to determine the rotation speed of the rf antenna and the dimension of the rf antenna in the flow direction. In this embodiment, the radio frequency antenna may have two different rotation modes, such as the first rotation mode described in fig. 3 or the second rotation mode described in fig. 4, which are not described herein again. After the rotation mode of the wireless radio frequency antenna is determined, the time for the wireless radio frequency antenna to rotate for one circle is also determined.

Preferably, the dimension Y of the radio frequency antenna_flowThe moving speed V of the wireless radio frequency antenna along the X-axis direction_flowThe following requirements should be met: t is_cover＝Y_flow/V_flow>>n/f_readerWherein f is_readerThe read frequency of the reader/writer 56, the minimum effective read time T_minvalue＝n/f_reader，n＝180/L_obewidth，L_obewidthThe lobe width of the radio frequency antenna. In the above-mentioned requirements, it is necessary to,>>is much larger than that, namely Y_flow/V_flowThe ratio of (a) to (b) needs to be much larger than n/f_readerThe numerical value of (c).

Then, step S62 is executed to calculate the ratio of the width of the gate diameter channel in the non-flow velocity direction to the width of the rf antenna. The non-flow direction in this embodiment is a relatively stationary direction, and is taken as an example of a RF antenna disposed on the top of the carriage 50, the non-flow direction is along the Y-axis, and it is assumed that the width of the door path along the Y-axis is W_YThe width of the radio frequency antenna along the Y-axis direction is W_antThen the value n calculated in step S62_YThe following formula can be used for calculation: n is_YRounding (W)_Y/W_ant) +1, that is, at the top of the door diameter channel, the number of the radio frequency antennas arranged along the Y-axis direction is 1 after the ratio of the width of the door diameter channel in the Y-axis direction to the width of the radio frequency antenna is rounded, and therefore, the number of the radio frequency antennas is greater than the ratio.

Similarly, if the RF antennas are disposed on both sides of the carriage 50 in the Y-axis direction, the non-flow direction is the Z-axis direction, and the number n of RF antennas on both left and right sides of the carriage 50_ZRounding (W)_Z/W_ant) +1, wherein W_ZIs the maximum height, W, of the load 45 on the carriage 50 in the Z-axis direction_antIs the width of the rf antenna located on the left and right sides of the carriage 50 in the Z-axis direction.

Then, step S63 is executed to determine the maximum number N of rf antenna channels of the reader/writer 56, i.e. the upper limit of the number of rf antennas that can be received by the reader/writer 56, where the sum of the rf antennas disposed on the top, left and right sides of the carriage 50 needs to be less than or equal to the maximum number N of rf antenna channels of the reader/writer 56, otherwise, the reader/writer 56 may not completely read the data of all the rf antennas.

Next, step S64 is executed to determine the number of arranged rf antennas according to the results of the calculation in steps S62 and S63, specifically, if the sum of the numbers of rf antennas arranged on the top and left and right sides of the carriage 50 calculated in step S62 does not exceed the maximum number N of rf antenna lanes of the reader/writer 56, a plurality of rf antennas are arranged according to the number of rf antennas calculated in step S62, and if the sum of the numbers of rf antennas arranged on the top and left and right sides of the carriage 50 calculated in step S62 exceeds the maximum number N of rf antenna lanes of the reader/writer 56, the number of arranged rf antennas is N, that is, the maximum number of rf antenna lanes of the reader/writer 56. And the plurality of radio frequency antennas are not overlapped with each other in the non-flow velocity direction.

Finally, step S65 is executed to determine the moving speed of the rf antennas, i.e. the moving speed of the carriage 50 along the X-axis direction on the guide rail 51, according to the number of the rf antennas. Specifically, the following relationship may be used for calculation: antenna coverage time T of electronic tag_coverRadio frequency antenna flow rate to coverage size/radio frequency antenna, wherein the antenna coverage time T of the electronic tag_coverA time less than one cycle of rotation of the radio frequency antenna is required.

According to the above method, the moving speed of the radio frequency antenna can be calculated, that is, the moving speed of the sliding frame 50 can be determined, and it can be ensured that the electronic tags on the goods 45 passing through the door diameter passage 40 can be covered by the radio frequency antenna and can be correctly read.

Generally, since the width of the door diameter passage 40 in the Y-axis direction is large, if a sufficient number of radio antennas are required to be arranged in the Y-axis direction of the door diameter passage 40, the number of radio antennas required to be arranged is large, and may exceed the maximum number N of radio antenna passages of the reader/writer 56, and for this reason, the number of radio antennas arranged on the top of the carriage 50 may not be able to completely cover the length of the door diameter passage 40 in the Y-axis direction. For this reason, the number of RF antennas located on the top of the carriage 50 may be less than the ratio of the width of the doorway path in the non-flow direction to the width of the RF antenna, i.e., n_Y×W_ant<W_YIn aIn this case, the carriage 50 needs to be operated in a special way to ensure that the electronic tag on each item 45 is identified.

Referring to fig. 7, when the rfid tag is identified by using the rf antenna, step S71 is first executed, the carriage moves to the edge along the X-axis direction, and step S72 is then executed to determine whether the number of the rf antennas is smaller than the ratio of the width of the door diameter passageway to the width of the rf antenna in the non-flow direction, for example, the Y-axis direction, if not, the number indicates that the rf antennas can completely cover the Y-axis direction of the door diameter passageway 40, the carriage does not move, and the reader/writer records all the read data of the rfid tag.

If the determination result in the step S72 is yes, step S73 is executed to integrally move the plurality of rf antennas in the non-streaming direction, for example, in the Y-axis direction. Specifically, the transmission bands such as chains are disposed on the cross bar 53 to drive the plurality of rf antenna holders 54 to integrally move along the Y-axis direction. Preferably, the distance per shift is (n)_Y-1)×W_antThe distance, that is, the distance of each movement of the plurality of radio frequency antennas is not greater than the total width of the plurality of radio frequency antennas in the relative stationary direction.

After the plurality of rf antennas are moved as a whole, step S74 is performed, the carriage is moved in the opposite direction of the flow velocity and moved to the edge, and then step S75 is performed to determine whether the strokes of the plurality of rf antennas completely cover the width of the door diameter passageway in the non-flow velocity direction, if yes, the movement of the carriage is ended, otherwise, step S73 is performed again until the strokes of the plurality of rf antennas completely cover the width of the door diameter passageway.

Thus, under the condition that the number of the radio frequency antennas is limited, the electronic tags on all goods 45 can be correctly identified, and the identification rate of the electronic tags is ensured.

Finally, it is to be emphasized that the invention is not limited to the above-described embodiments, for example, changes in the applied scenario, or changes in the type of radio frequency antenna used, etc., which are also intended to be included within the scope of the present invention.