JP2007214926A - Omnidirectional antenna and information reading apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an omnidirectional antenna capable of receiving the radio waves of an omnidirectional RF tag with a small amount of area, by forming three-dimensional loop coils arranged on two-axis planes each in X-, Y-, and Z-axis planes, and a plane loop coil arranged along one axis plane in one piece for composing one antenna block, and by selecting the loop coil on each axis plane by time sharing. <P>SOLUTION: An information reading apparatus 300 comprises the omnidirectional antenna 40; a loop coil selector 52 for selecting the loop coils on each axis plane for composing the omnidirectional antenna 40 successively; a reader or a reader/writer 100 for transmitting carrier power based on a prescribed modulation/demodulation system, and for transferring data without any contact via the antenna of an IC card; and a PC50 for controlling the loop coil selector 52 and the reader or reader/writer 100. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an omnidirectional antenna and an information reading device, and more particularly, to a non-contact antenna capable of receiving recorded data recorded on a non-contact information recording medium as a radio wave regardless of the orientation and orientation of the non-contact information recording medium. The present invention relates to a directional antenna and an information reading apparatus using the omnidirectional antenna.

  In recent years, new information recording media called IC cards are widely available on the market. The IC card is a generic name for a readable / writable recording medium having a card-like or sheet-like shape such as a credit card, a bank card, or a point card, and having an IC incorporated in or on the card. In particular, the non-contact type IC card is often used as a commuter pass or a prepaid card used when entering or leaving a station of a transportation facility such as a railway. Further, as a kind of non-contact type IC card, there is an RF tag (Radio Frequency tag) that is structurally exactly the same as the non-contact type IC card and records management information relating to identification number and history information. As a kind of RF tag, a non-contact type RF tag (hereinafter simply referred to as an RF tag) used for classifying and managing mails or packages is known.

  Conventionally, for example, when reading / writing management information with a reader / writer while a baggage attached with an RF tag is being conveyed by a belt conveyor, if the reader / writer's antenna is fixed at a fixed position, the baggage must be transferred before the belt conveyor starts its conveyance. It was necessary to manually set the direction of the baggage in advance so that the position of the RF tag attached to the device was confirmed and the RF tag was directed to the antenna side of the reader / writer. In addition, when it is desired to make it possible to read and write management information without performing such complicated prior operations, the reader / writer is also used in other directions expected to be most suitable for reading and writing information with respect to the RF tag. It was necessary to install multiple antennas.

In order to solve such a problem, the prior art disclosed in Patent Document 1 is an interrogator system in which a plurality of interrogators wirelessly communicate the same signal to a moving transponder (IC card). An interrogator is provided with overlapping antenna communicable areas to expand the communicable area, and the interrogator receives and transmits signals from other interrogators by synchronizing transmission / reception via the antenna. An interrogator system that prevents interference is disclosed.
JP 2003-283367 A

  However, in the conventional technique disclosed in Patent Document 1 and the conventional method of reading / writing management information by a reader / writer while being conveyed by a belt conveyor, a plurality of antennas must be installed in each direction. In addition to the problem of increased costs due to the increase in the number of installed devices and the securing of a large installation space, there is a problem in that the conveyance distance becomes longer because articles attached with RF tags must be conveyed to all antenna positions. is there.

In view of such problems, the present invention integrally forms a three-dimensional loop coil disposed on each of two axial planes of the X, Y, and Z-axis planes and a planar loop coil disposed along one axial plane. It is an object of the present invention to provide an omnidirectional antenna that can receive radio waves of an omnidirectional RF tag with a small area by configuring one antenna block and selecting loop coils on each axis plane in a time division manner. To do.
Another object is to read the RF tag information efficiently by devising a method for selecting the loop coil of each axial plane constituting the antenna block.

In order to solve this problem, the present invention provides a non-directional antenna for receiving recorded data recorded on a non-contact information recording medium as a radio wave, and is an X-axis plane and a Y-axis that are orthogonal to each other. Two solid loop coils each having an axis orthogonal to two axial planes of the plane and the Z-axis plane, and a planar loop coil arranged parallel to the other one axial plane It is characterized by.
A feature of the omnidirectional antenna of the present invention is that a three-dimensional loop coil is arranged on two axial planes of the X, Y, and Z axis planes, and a planar loop coil is arranged along the remaining axial plane. And the axis | shaft of each solid loop coil is comprised so that it may mutually orthogonally cross, and a planar loop coil is arrange | positioned in parallel with respect to the axis | shaft.

According to a second aspect of the present invention, an end surface shape of the three-dimensional loop coil is a rectangle or an ellipse.
In order to make the omnidirectional antenna of the present invention as small as possible, it is necessary to reduce the overall thickness. Therefore, in the present invention, the end face shape of the three-dimensional loop coil is rectangular or elliptical.

A third aspect of the present invention provides the omnidirectional antenna according to the first or second aspect, a loop coil selector for selecting any one of the loop coils constituting the omnidirectional antenna, and the non-contact information recording medium A reader or reader / writer for transmitting carrier power and transmitting / receiving data based on a predetermined modulation / demodulation method via an antenna, and a control means for controlling the loop coil selector and the reader / reader / writer. The means uses the loop coil selector to selectively switch one of the loop coils at regular time intervals, while using the reader or reader / writer via the antenna of the non-contact information recording medium. The transmission / reception of carrier power and the transmission / reception of data are performed based on the modulation / demodulation method.
The information reading device of the present invention is recorded on a non-contact information recording medium via the omnidirectional antenna of the present invention, a loop coil selector that sequentially selects each loop antenna constituting the antenna, and the selected loop coil. A reader or reader / writer for reading and writing data and a control means for controlling these, and the control means exchanges data with the reader or reader / writer while sequentially selecting the loop coil selector at regular time intervals. is there.

According to a fourth aspect of the present invention, the control means lengthens the use time of a specific loop coil among the loop coils of each axis plane by the loop coil selector.
Of the X, Y, and Z axis planes, if the Z axis plane is an axis plane that is physically parallel to the ground, the probability that the antenna of the non-contact information recording medium is close to the axis plane is increased. In such a case, data transfer from the Z-axis plane is the largest. Therefore, in the present invention, an axial plane with high data exchange is determined in advance, and the axial plane is preferentially selected to extend the use time.

According to a fifth aspect of the present invention, there is provided an exchange number recording means for recording the number of exchanges of the recording data from each loop coil for each loop coil, and the control means is recorded in the exchange number recording means by the loop coil selector. It is characterized by sequentially selecting from the loop coils having a large number of exchanges.
The present invention counts the number of data exchanges for each loop coil, selects a loop coil with a large number of data exchanges, and controls the loop coil selector so as to shift to a smaller number of loop coils. The transfer number recording means may be provided in the control means or in the reader or reader / writer.

A sixth aspect of the present invention provides a plurality of omnidirectional antennas according to the first or second aspect, a loop coil selector that selects any one of the loop coils constituting the omnidirectional antenna, and the omnidirectional elements. A block selector that enables any one of the directional antennas, a reader or reader / writer that transmits and receives data based on a predetermined modulation / demodulation method via the antenna of the non-contact information recording medium, and A loop coil selector, a block selector, and a control means for controlling the reader or reader / writer, wherein the control means selects any one of the omnidirectional antennas by the block selector, While performing the operation of sequentially selecting each loop coil constituting the selected omnidirectional antenna by the loop coil selector with respect to all the omnidirectional antennas, Through the antenna of the noncontact information recording medium by serial reader or writer, and performs transmission and reception of transmission data of the transport power based on a predetermined demodulation scheme.
The present invention further includes a block selector that includes a plurality of the omnidirectional antennas of the present invention and that enables any one of the omnidirectional antennas. That is, one omnidirectional antenna is made effective by the block selector, and the loop coils on the respective axis planes constituting the selected omnidirectional antenna are sequentially selected by the loop coil selector. When the data transfer by all the loop coils of one omnidirectional antenna is completed, the next omnidirectional antenna is validated and this operation is performed on all the omnidirectional antennas.

According to a seventh aspect of the present invention, the control means selects any one of the omnidirectional antennas by the block selector, and uses the same axial plane in each axial plane constituting the selected omnidirectional antenna. The operation of selecting a loop coil by the loop coil selector is performed for all the omnidirectional antennas, and when the operation is completed, another loop coil is selected by the loop coil selector and the operation is repeated. It is characterized by.
In the present invention, a loop coil of one axial plane is selected by the loop coil selector, and all omnidirectional antennas are sequentially selected by the block selector in this state. When one cycle is completed, the loop coil selector selects the loop coil of the next axial plane, repeats the same operation as described above, and repeats until selection of all the axial planes is completed.

According to an eighth aspect of the present invention, a shield member is disposed in a portion where the omnidirectional antennas are adjacent to each other.
When a plurality of omnidirectional antennas are arranged adjacent to each other, the magnetic field generated from the loop coil leaks to the loop coil of the adjacent omnidirectional antenna, and data is simultaneously output from the plurality of omnidirectional antennas. That is, when the position of the article is determined based on the position of the omnidirectional antenna, it cannot be accurately determined. Therefore, in the present invention, a shield member is disposed in a portion where an omnidirectional antenna is adjacent to prevent a leakage magnetic field.

  According to the present invention, the three-dimensional loop coil is arranged on any two of the X, Y, and Z axis planes, and the plane loop coil is arranged along the remaining axis planes. The three-dimensional loop coils are configured such that the axes of the three-dimensional loop coils are orthogonal to each other, and the planar loop coils are arranged in parallel to the axes. Information can be received as radio waves.

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. However, the components, types, combinations, shapes, relative arrangements, and the like described in this embodiment are merely illustrative examples and not intended to limit the scope of the present invention only unless otherwise specified. .
FIG. 1 is a block diagram showing a configuration of a general reader / writer. The reader / writer 100 is controlled by a PC 50 that exchanges data with the reader / writer 100 and controls the entire system. The reader / writer 100 includes a transmission / reception device 1 that controls a data communication protocol with an external PC 50, a control device 2 that controls the operation of the entire reader / writer 100, firmware that records a procedure for operating the control device 2, and read data A memory device 3 for storing data, a modulator 4 for modulating data from the control device 2 on a carrier wave, an input device 5 for inputting an operation command, and a display device 6 for displaying information controlled by the control device 2 A power amplifier 7 that amplifies the power supply signal that is an AC signal from the control device 2 and a write command from the modulator 4, and a detector demodulator that converts the carrier wave received from the loop antenna 9 into binary data 8 and a loop antenna 9 for exchanging power and data with an IC card (RF tag) (not shown). .

  Next, before describing the operation of the reader / writer 100 according to this configuration, the configuration of the IC card (RF tag) (non-contact information recording medium) will be described first. FIG. 2 is a block diagram showing the configuration of the IC card (RF tag). The IC card (RF tag) 200 receives an antenna 20 that transmits / receives data using a power carrier wave from the reader / writer 100, a transmission / reception circuit 21 that generates a write command read command, and a power carrier wave from the antenna 20. A power generation circuit 22 that rectifies and converts it into DC power, a memory device 23 that manages storage of control firmware and data, a modulator 24 that modulates a transmission command from the control circuit 26 with a carrier wave, and transmission / reception It comprises a detector 25 that converts carrier wave data from the circuit 21 into binary data, and a control circuit 26 that controls the overall operation of the IC card (RF tag) 200.

  Next, each operation will be described with reference to FIGS. 1 and 2 together. When a power supply (not shown) is turned on, the reader / writer 100 starts an operation according to a program stored in the memory device 3 after the initial operation of the control device 2. First, initialization is performed. Next, the control device 2 alternately transmits a power supply signal to be supplied to the IC card (RF tag) 200 and a polling signal from the power amplifier 7. The signal is radiated to the outside from the loop antenna 9 as an electromagnetic wave. Next, when the IC card (RF tag) 200 comes close to the reader / writer 100, the antenna 20 receives a power supply signal, rectifies the carrier wave by the power generation circuit 22 and converts it to DC power, and then converts it into the RF tag. To all circuits. When power is supplied and the control circuit 26 is driven, control is started in accordance with a program stored in the memory device 23.

  Next, the control circuit 26 first demodulates the command from the transmission / reception circuit 21 by the detector 25, converts it to a binary signal, and analyzes the command. As a result, when it is recognized that it is called, the response is modulated by the modulator 24 and transmitted from the antenna 20 via the transmission / reception circuit 21. The reader / writer 100 receives this response with the loop antenna 9, converts it into a binary code with the detector demodulator 8, analyzes it with the control circuit 2, and the IC card (RF tag) 200 conforms to the standard IC card ( RF tag). Thereby, polling is performed between the reader / writer 100 and the IC card (RF tag) 200 thereafter.

  FIG. 3 is a diagram for explaining the relationship between the orientation of the IC card and the lines of magnetic force by disassembling the loop coil on each axial plane of the omnidirectional antenna of the present invention. For convenience of explanation, the direction of FIG. 3A is called a Z-axis plane, the direction of FIG. 3B is called a Y-axis plane, and the direction of FIG. 3C is called an X-axis plane. First, on the Z-axis plane, assuming that the loop coil 31 is configured on a plane, the magnetic field lines 30 intersect the IC card 200a arranged in parallel to the loop coil 31 at a substantially right angle. In the Y-axis plane, the loop coil 32 is configured to be perpendicular to the Z-axis plane, so that the magnetic force lines 33 intersect the IC card 200b disposed perpendicular to the IC card 200a at a substantially right angle. become. In the X-axis plane, the loop coil 34 is configured perpendicular to the Z-axis plane and rotated 90 degrees with respect to the Y-axis plane, so that the IC card 200c rotated 90 degrees with respect to the IC card 200b On the other hand, the magnetic force lines 35 intersect at a substantially right angle. That is, as shown in FIG. 3D, the three-dimensional loop coils 34 and 32 are arranged on the X, Y, and Z axis planes of the X, Y, and Z axis planes, and the plane loop coils 31 are arranged along the remaining Z axis planes. . The axes of the three-dimensional loop coils 34 and 32 are configured to be orthogonal to each other, and the planar loop coil 31 is arranged in parallel to the axis. Information can be received as radio waves.

  That is, when the omnidirectional antenna 40 is formed by integrally configuring the X, Y, and Z axis plane loop coils 34, 32, and 31, for example, the loop coil 31 transmits and receives radio waves to and from the IC card 200a. Thus, the IC card 200b is exchanged with radio waves by the loop coil 32, and the IC card 200c is exchanged with radio waves by the loop coil 34. Therefore, radio waves can be transmitted and received by the omnidirectional antenna 40 no matter what direction the IC card 200 is arranged. Note that when the magnetic field lines intersect each IC card at right angles, the magnetomotive force is the largest, and radio waves are exchanged efficiently. However, radio waves can be exchanged even at a predetermined angle. Also, when the IC card is tilted, the magnetic field lines from the loop coils of two different axial planes may intersect the IC card. In this case, information can be received from both loop coils and ORed. Done.

  FIG. 4 is an exploded view for explaining the loop coil on each axis plane of the omnidirectional antenna of the present invention. The same components will be described with the same reference numerals as in FIG. FIG. 4A is a diagram of a Z-axis plane loop coil. For example, a coil wire 31b wound in a planar shape is held by a holding member 31a, and both ends of the coil wire 31b are external to a part of the holding member 31a. The connection part 31c connected to is comprised. FIG. 4B is a diagram of a Y-axis plane loop coil. For example, a coil wire 32d wound in a planar shape is held by holding members 32a to 32c, and is held on a part of the holding members 32a and 32c. Both ends of the coil wire 32d are configured to include connection portions 32e connected to the outside. FIG. 4C is a diagram of a loop coil in the X-axis plane. For example, a coil wire 34d wound in a planar shape is held by holding members 34a to 34c, respectively, and is held on a part of the holding members 34a and 34c. The coil wire 34d is provided with connection portions 34e connected to the outside at both ends, and is configured to rotate 90 degrees with respect to the loop coil 32 of FIG. 4B.

  FIG. 5 is a perspective view showing an external configuration of the omnidirectional antenna of the present invention. The omnidirectional antenna 40 is made of resin or the like, and connects a cover 41 that protects and holds a loop coil on each internal axis plane, and both ends of each loop coil and an external loop coil selector (described later). Connector 43 and a bush 44 attached to the bottom of the cover 41. And the article | item which attached the IC card or RF tag to read is mounted in the installation part 42, and information is read. In this embodiment, for example, even when a plurality of articles attached with an RF tag are placed on the installation unit 42 without being aware of the orientation, the loop coils on each axis plane can be switched in a time division manner and read. Therefore, the information in the bag can be read at a time only by placing an article with a random RF tag orientation in the bag and placing it on the installation unit 42. Moreover, as an external appearance shape of the omnidirectional antenna 40, it can comprise in a book shape by making the end surface shape of the at least 2 axial plane of each axial plane into a rectangle or an ellipse. The end face shape means a shape seen from one end face side in the axial direction of the loop coil.

FIG. 6 is a block diagram of the information reading apparatus according to the first embodiment of the present invention. The information reading apparatus 300 includes an omnidirectional antenna 40 described above, a loop coil selector 52 that sequentially selects each loop coil (hereinafter referred to as LC) constituting the omnidirectional antenna 40, and an IC card antenna. Via a reader / reader / writer (hereinafter referred to as RW) 100 that performs non-contact transmission of carrier power and transmission / reception of data based on a predetermined modulation / demodulation method, and a PC (control) that controls the loop coil selector 52 and the RW 100. Means) 50.
The PC 50 of the information reading apparatus 300 uses the RW 100 while selectively switching one of the LCs 34, 32, 31 constituting the omnidirectional antenna 40 by a loop coil selector 52 at regular intervals. Transmission of carrier power and transmission / reception of data based on a predetermined modulation / demodulation method are performed in a non-contact manner via an antenna of the IC card 200.

  FIG. 7 is a flowchart for explaining a selection method of the loop coil selector of the information reading apparatus according to the first embodiment. This will be described with reference to FIG. In this description, in order to simplify the description, a case where information of one IC card is read will be described. FIG. 7A shows a method of sequentially performing the selection procedure at equal intervals. For example, the loop coil selector 52 selects the X-axis plane LC34 as an initial point (S1). In this state, the PC 50 checks whether information can be read from the X-axis plane LC 34 via the RW 100 (S2). If it is read, the process proceeds to step S7 and the data is taken into the PC 50 (S7). If the data cannot be read in step S2, the loop coil selector 52 selects the Y-axis plane LC32 (S3). In this state, the PC 50 checks whether information can be read from the Y-axis plane LC 32 via the RW 100 (S4). If it is read, the process proceeds to step S7 and the data is taken into the PC 50 (S7). If the data cannot be read in step S4, the loop coil selector 52 selects the Z-axis plane LC31 (S5). In this state, the PC 50 checks whether information can be read from the Z-axis plane LC31 via the RW 100 (S6), and if it can be read, the data is taken into the PC 50 (S7). Although the process may end in this step, it may not be readable on all the axial planes, so the process may be repeated by returning to step S1.

  FIG. 7B shows a method of weighting the selection procedure. For example, the loop coil selector 52 selects the Z-axis plane LC31 as an initial point (S10). In this state, the PC 50 checks whether information can be read from the Z-axis plane LC31 via the RW 100 (S11). If it is read, the process proceeds to step S17 and the data is taken into the PC 50 (S17). If data cannot be read in step S11, the reading operation of the Z-axis plane LC31 is repeated n times (S12), and then the loop coil selector 52 selects the X-axis plane LC34 (S13). In this state, the PC 50 checks whether information can be read from the X-axis plane LC 34 via the RW 100 (S14), and if it can be read, the data is taken into the PC 50 (S17). If the data cannot be read in step S14, the loop coil selector 52 selects the Y-axis plane LC32 (S15). In this state, the PC 50 checks whether information can be read from the Y-axis plane LC 32 via the RW 100 (S16), and if it can be read, the data is taken into the PC 50 (S17). Although the process may end in this step, it may be impossible to read in all the axial planes, so the process may be repeated by returning to step S10.

  FIG. 7C shows a method of learning and performing the selection procedure. For example, as an initial point, the loop coil selector 52 selects the axis plane with the largest number of readings (S21). The number of readings is stored in the memory of the PC 50. Next, in this state, it is checked whether or not information can be read from the axial plane connected by the PC 50 via the RW 100 (S22). If it is read, 1 is added to the count value of the axial plane (S27), and the data is obtained. The data is taken into the PC 50 (S28). Next, the loop coil selector 52 selects the axis plane having the second highest number of readings (S23). Next, in this state, it is checked whether or not information can be read from the axial plane connected by the PC 50 via the RW 100 (S24). If it is read, 1 is added to the count value of the axial plane (S27), and the data is The data is taken into the PC 50 (S28). Next, the loop coil selector 52 selects the axial plane having the third highest number of readings (S25). Next, in this state, the PC 50 checks whether information can be read from the axial plane connected via the RW 100 (S26). If it can be read, 1 is added to the count value of the axial plane (S27), and the data is obtained. The data is taken into the PC 50 (S28). Although the process may end in this step, it may be impossible to read in all the axial planes, so the process may be repeated by returning to step S21.

  FIG. 8 is a diagram showing a configuration of an information reading apparatus according to the second embodiment in which a plurality of omnidirectional antennas according to the present invention are arranged. The information reading apparatus 310 includes a plurality of omnidirectional antennas 40 (A to I in this example) disposed on a support member 56, and a shield member 55 that blocks a magnetic field at a portion adjacent to each omnidirectional antenna. It has been. Thereby, it is possible to collectively read information on a large number of articles and RF tags attached to large articles. In addition, in order to read information correctly, each omnidirectional antenna AI needs to make the space | interval of an adjacent part as narrow as possible.

FIG. 9 is a block diagram of an information reading apparatus according to the second embodiment of the present invention. The same components will be described with the same reference numerals as in FIG. The information reading device 320 includes a plurality of omnidirectional antennas 40 (A to I in this example), a loop coil selector 52 that sequentially selects a loop coil of each axial plane constituting the omnidirectional antenna 40, and In addition, the block selector 57 that enables any one of the omnidirectional antennas A to I and the antenna of the IC card 200 contactlessly transmit carrier power and exchange data based on a predetermined modulation / demodulation method. And a PC (control means) 50 that controls the loop coil selector 52, the block selector 57, and the RW 100.
The PC 50 of the information reading device 320 selects any one of the omnidirectional antennas A to I by the block selector 57, and sets the loop coil of each axis plane constituting the selected omnidirectional antenna as a loop coil. By performing the switching operation by the selector 52 for all of the omnidirectional antennas, the transmission of carrier power and the transmission / reception of data based on a predetermined modulation / demodulation method are contactlessly performed by the RW 100 via the antenna of the IC card 200. This is what you do.

  FIG. 10 is a flowchart illustrating a method for selecting an information reading apparatus according to the second embodiment. This will be described with reference to FIG. In order to simplify the description, the determination as to whether or not the data can be read is omitted. FIG. 10A shows a method of selecting the next block after reading all the axial plane data for each block. That is, the PC 50 selects the first block as an initial by the block selector 57 (for example, the omnidirectional antenna A) (S31). In this state, the data is sequentially selected by the loop coil selector 52 and the data of each axis plane is read by the RW 100 (S32). Next, the PC 50 selects the next block by the block selector 57 (for example, omnidirectional antenna B) (S33). Then, it is checked whether it is the last block (S34). If it is not the last block, the process returns to step S32 and is repeated.

  FIG. 10B shows a method in which after reading the same axial plane for each block, the next block is selected, and the LC of the next axial plane is selected by the loop coil selector and repeated. That is, the PC 50 selects the first block as the initial by the block selector 57 (for example, the omnidirectional antenna A) (S41). In this state, the loop coil selector 52 selects the LC on the X-axis plane and reads the data with the RW 100 (S42). Next, the PC 50 selects the next block by the block selector 57 (for example, the omnidirectional antenna B) (S43). Then, it is checked whether or not the final block (for example, omnidirectional antenna I) has been reached (S44), and if it is not the final block, the process returns to step S42 and is repeated. When it becomes the last block in step S44, the PC 50 selects the first block by the block selector 57 (for example, omnidirectional antenna A) (S45). In this state, the LC on the Y-axis plane is selected by the loop coil selector 52 and the data is read by the RW 100 (S46). Next, the PC 50 selects the next block using the block selector 57 (for example, the omnidirectional antenna B) (S47). Then, it is checked whether or not the final block (for example, omnidirectional antenna I) has been reached (S48), and if it is not the final block, the process returns to step S46 to repeat. When the final block is reached in step S48, the PC 50 selects the first block by the block selector 57 (for example, omnidirectional antenna A) (S49). In this state, the LC on the Z-axis plane is selected by the loop coil selector 52 and the data is read by the RW 100 (S50). Next, the PC 50 selects the next block by the block selector 57 (for example, the omnidirectional antenna B) (S51). Then, it is checked whether or not the final block (for example, omnidirectional antenna I) has been reached (S52), and if it is not the final block, the process returns to step S50 and is repeated. If it becomes the last block in step S52, it will return to step S41 and repeat.

As described above, according to the present invention, the three-dimensional loop coils 34 and 32 are arranged on the X and Y axis planes of the X, Y, and Z axis planes, and the planar loop coil 31 is arranged along the remaining Z axis planes. The axial planes of the three-dimensional loop coils 34 and 32 are configured to be orthogonal to each other, and the planar loop coil 31 is arranged in parallel to the axial plane, so that the IC card 200 is independent of the orientation of the IC card 200. Can be received as radio waves.
Moreover, since the end surface shape of the three-dimensional loop coils 34 and 32 is a rectangle or an ellipse, the shape of the omnidirectional antenna 40 can be made small and thin.
In addition, since the PC 50 performs the data transmission / reception by the RW 100 while sequentially selecting the loop coil selector 52 at regular time intervals, the data from the loop coils on each axis plane can be uniformly received.

In addition, since an axial plane with high data transmission / reception is determined in advance and the axial plane is preferentially selected to extend the usage time, the probability of receiving information recorded on the IC card 200 is increased. Can do.
In addition, since the number of data exchanges is counted for each loop coil, the loop coil selector 52 is controlled so as to select the loop coil with the largest number of exchanges and sequentially shift to the smaller loop coil. You can learn the number of exchanges that change.
The block selector 57 enables one omnidirectional antenna 40, and the loop coil selector 52 sequentially selects the loop coils of the respective axis planes constituting the selected omnidirectional antenna 40. When the data transfer by all the loop coils of one omnidirectional antenna 40 is completed, the next omnidirectional antenna is validated and this operation is performed for all the omnidirectional antennas. The position can be moved while determining the presence or absence of data from the sex antenna.

Further, a loop coil of one axial plane is selected by the loop coil selector 52, and in this state, all the omnidirectional antennas A to I are sequentially selected by the block selector 57. Thus, the loop coil of the next axial plane is selected and the same operation as described above is repeated until the selection of all the axial planes is completed, so that the entire situation can be grasped for the time being.
In addition, since the shield member 55 is disposed in a portion where the omnidirectional antennas A to I are adjacent to each other, it is possible to prevent a magnetic field generated from the loop coil from leaking to the loop coil of the adjacent omnidirectional antenna. .

It is a block diagram which shows the structure of a general reader / writer. It is a block diagram which shows the structure of an IC card (RF tag). It is a figure explaining the relationship between the direction of an IC card, and a magnetic force line by disassembling the loop coil of each axis plane of the omnidirectional antenna of the present invention. It is a figure which decomposes | disassembles and demonstrates the loop coil of each axial plane of the omnidirectional antenna of this invention. It is a perspective view which shows the external appearance structure of the omnidirectional antenna of this invention. 1 is a block diagram of an information reading apparatus according to a first embodiment of the present invention. It is a flowchart explaining the selection method of the loop coil selector of the information reading apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows the structure of the information reading apparatus which concerns on 2nd Embodiment which has arrange | positioned multiple the omnidirectional antenna of this invention. It is a block diagram of the information reading apparatus which concerns on the 2nd Embodiment of this invention. It is a flowchart explaining the selection method of the information reader which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

  31 Z-axis planar loop coil, 32 Y-axis planar loop coil, 34 X-axis planar loop coil, 40 omnidirectional antenna, 41 cover, 43 connector, 44 bush, 50 PC, 52 loop coil selector, 57 block selector, 100 reader or reader / writer, 300 information reader

Claims (8)

An omnidirectional antenna that receives recorded data recorded on a non-contact information recording medium as radio waves,
Two three-dimensional loop coils having axes orthogonal to two of the X-axis plane, Y-axis plane, and Z-axis plane that are orthogonal to each other, and arranged in parallel to the other one axis plane An omnidirectional antenna comprising a planar loop coil.   The omnidirectional antenna according to claim 1, wherein an end face shape of the three-dimensional loop coil is a rectangle or an ellipse. The omnidirectional antenna according to claim 1 or 2, a loop coil selector that selects any one of the loop coils constituting the omnidirectional antenna, and the antenna of the non-contact information recording medium A reader or reader / writer for transmitting carrier power and transmitting / receiving data based on a predetermined modulation / demodulation method, and a control means for controlling the loop coil selector and the reader or reader / writer,
The control means uses the loop coil selector to selectively switch one of the loop coils at regular intervals, and uses the reader or reader / writer via the antenna of the non-contact information recording medium. An information reading apparatus that performs transmission of carrier power and transmission / reception of data based on a predetermined modulation / demodulation method.   4. The information reading apparatus according to claim 3, wherein the control means lengthens the use time of a specific loop coil among the loop coils of the respective axis planes by the loop coil selector. A transfer count recording means for recording the transfer count of the recording data from each loop coil for each loop coil;
5. The information reading apparatus according to claim 3, wherein the control unit sequentially selects a loop coil having a large number of exchanges recorded in the exchange number recording unit by the loop coil selector. The plurality of omnidirectional antennas according to claim 1, a loop coil selector that selects any one of the loop coils constituting the omnidirectional antenna, and any one of the omnidirectional antennas A block selector that validates one, a reader or reader / writer that transmits and receives data based on a predetermined modulation / demodulation method via an antenna of the non-contact information recording medium, and the loop coil selector, A block selector and control means for controlling the reader or reader / writer,
The control means selects one of the omnidirectional antennas with the block selector, and sequentially selects the loop coils constituting the selected omnidirectional antenna with the loop coil selector. The carrier power is transmitted and the data is transmitted / received based on a predetermined modulation / demodulation method by the reader or the reader / writer via the antenna of the non-contact information recording medium while performing all of the omnidirectional antennas. An information reader characterized by.   The control means selects any one of the omnidirectional antennas by the block selector, and loops the same axial plane loop coil in each axial plane constituting the selected omnidirectional antenna as the loop. The operation selected by the coil selector is performed on all the omnidirectional antennas, and when the operation is completed, another loop coil is selected by the loop coil selector and the operation is repeated. Item 7. The information reading device according to Item 6.   The information reading apparatus according to claim 6, wherein a shield member is disposed in a portion where the omnidirectional antennas are adjacent to each other.

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