JP4579599B2 - RFID tag evaluation system - Google Patents

Description

  The present invention relates to an RFID (Radio Frequency Idenstification) evaluation system.

  The first purpose of RFID is to perform authentication (reading data in tags) by using RFID tags (sometimes called IC tags) instead of barcodes, and internationally standardize (ISO 18046: performance test). Method, performance evaluation, ISO18047: conformance test method, compatibility test). For RFID tag authentication, reliability is the most important requirement, and quality evaluation is indispensable.

  The present invention relates to an RFID evaluation system capable of evaluating performance in arbitrary positioning (positioning) of an RFID tag with respect to an RFID reader / writer as evaluation unique to RFID that approximates an actual environment.

  An RFID tag is a kind of IC card, but its shape is free and may be used in various usages for various purposes. Basically, when a specific radio signal (electromagnetic wave) from an interrogator (sometimes called a reader / writer) is received, the signal stored in the tag is detected by detecting the signal with the antenna of the RFID tag. Take out, modulate, and transmit by radio signal from the antenna. By receiving this with the interrogator antenna, the RFID tag data can be read.

As described above, the international standardization (ISO18046, ISO18047) of the evaluation specification of the RFID tag is in progress, but has not yet been determined. Regarding a conventional RFID-IC test method, a test wafer is specified for each IC (tag) with a probe on a semiconductor wafer on which a large number of ICs (tags) are formed. A method and apparatus for performing a test by transmitting a wireless signal and receiving a response from an IC is known (see Patent Document 1).
US Pat. No. 6,236,223

  The first purpose of the RFID tag is to replace the barcode, but there is a demand for a method of use that not only recognizes the individual but also makes use of the wireless characteristics. That is, in order to perform authentication wirelessly unlike a bar code, reading performance in various relative orientations between the RFID tag and the interrogator is required. In the conventional technique (Patent Document 1) described above, , It was not possible to realize a test for reading in various postures with respect to the reading device (antenna).

  An object of the present invention is to provide an RFID tag evaluation system capable of performing an evaluation in consideration of a degree of freedom of a relative posture peculiar to wireless authentication using an RFID tag.

  Since the present invention performs an evaluation (test) in consideration of the degree of freedom of the relative posture peculiar to wireless authentication, the RFID tag is spatially three-dimensionally positioned, and the test apparatus itself does not reflect the wireless (electromagnetic wave) (apparently, transmission) In this way, the electromagnetic wave intensity from the machine does not increase).

  FIG. 1 shows the principle configuration of the present invention. In the figure, 1 is a positioning device for a device under test, 10 is a device fixing part for holding the device under test (RFID tag), 16 is a reference table on which each part is mounted, and 11 is a device mounting part 10 for mounting the device under test. A support portion that can move in the vertical direction corresponding to the elevation angle with respect to the plane of the reference table (16 described later), 110 is a radial rail that guides the movement of the DUT fixing portion 10 on the support portion 11, 111 is an elevation hinge that supports the end of the support portion 11 so that the end of the support portion 11 can be rotated in the vertical direction with respect to the horizontal plane of the reference table 16 (the elevation angle is variable). , A radial fluctuation transmission unit 120 for transmitting power that changes the radial radius (r), which is the distance between the hinge 111 and the DUT fixing part 10, and 120 is a radial drive for driving the radial fluctuation transmission unit 12. And 13 are provided on the reference table 16 to which the base of the support 11 is attached. The vertical part 14 provided directly is adjusted to the length of the thread whose end is fixed to the support part 11, and the support part 11 (including the radial rail 110) is formed with respect to the horizontal plane including the reference table 16. Elevation angle fluctuation transmission section for transmitting power for varying the elevation angle (θ), 140 is an elevation angle drive section for driving the elevation angle fluctuation transmission section 14, and 15 is a vertical provided at the base of the support section 11 (position of the hinge 111). An azimuth angle variation transmitting unit 150 for transmitting power for changing the azimuth angle (represented by φ and also referred to as a rotation angle) by rotating the support portion 11 and the vertical portion 13 together with the reference base 16 with the portion 13 as a central axis, and 150 is an azimuth angle An azimuth rotation drive unit 17 that drives the fluctuation transmission unit 15 transmits a radio signal for a test (reading and writing) provided in the azimuth fluctuation transmission unit 15 and receives a signal from the device under test. It is an antenna.

  2 generates a radio signal for testing and outputs it to the antenna 17 to take out a response signal from the RFID tag as a device under test from the antenna 17 and perform evaluation, and a plurality of drive systems for positioning the RFID tag. A test apparatus 3 that outputs a signal to be controlled is provided at each position in a three-dimensional space with respect to the center of the antenna 17 (provided that the device under test holding part 10 holding an RFID tag as a product to be tested is based on the principle of polar coordinates). Drive for generating signals a, b, and c for driving the radial drive unit 120, the elevation drive unit 140, and the azimuth rotation drive unit 150, respectively, in order to move in the Z-axis (vertical direction range of Z ≧ 0). System controller.

  Each part of the positioning device 1 of the device under test is made of a material with low reflection of electromagnetic waves and a low dielectric constant, and is composed of each radial drive unit 120, elevation drive unit 140, and azimuth rotation drive unit 150. The degree-of-freedom mechanism transmits a driving force by a plastic thread or the like. The driving force is generated by a driving source such as a stepping motor. The driving source is also covered with an electromagnetic wave absorber to prevent electromagnetic wave reflection. The offset (deviation) between the center of the antenna 17 and the radial distance reference and the elevation rotation center is converted by the evaluation / storage device 20 (FIG. 5) or an external device (personal computer).

  A test object to be evaluated (tested) is set in the test object fixing portion 10 and the test apparatus 2 instructs the drive system control apparatus 3 to set initial values of the moving radius, the elevation angle, and the azimuth angle. The radial drive unit 120, the elevation drive unit 140, and the azimuth rotation drive unit 150 are driven to transmit a test signal from the test apparatus 2 and receive a response from the device under test via the antenna 17. Judgment is made whether the performance is achieved and the result is recorded. Subsequently, the same test is performed each time one of the values of the radius, elevation, and azimuth is updated, and the test is repeated until the final radius, elevation, and azimuth are reached. Evaluation is obtained.

  According to the present invention, all three-dimensional positions are changed by changing the radius, elevation, and azimuth with respect to an antenna (planar antenna) that transmits a radio signal of a test and transmits / receives electromagnetic waves to / from the RFID tag of the device under test. It is possible to automatically perform an operation to evaluate by evaluating. In addition, each degree of freedom (radial direction, elevation angle, azimuth) mechanism (linear motion mechanism, rotation mechanism, and turntable) is made of plastic or dry wood material with low dielectric constant and low reflection of electromagnetic waves. The driving force is transmitted individually and independently with a plastic thread to determine the three-dimensional position of the RFID tag, and the relative posture between the RFID tag and the planar antenna of the test wave transmission / detection device can be determined. Therefore, the RFID tag can be detected without any influence on the test wave without correction, and the RFID tag can be evaluated quickly and accurately.

  FIG. 2 shows the configuration of an embodiment of the positioning device for the device under test. In the figure, reference numeral 10 denotes a specimen fixing part similar to that shown in FIG. 1, 11 denotes an elongated plate-like supporting part on which the specimen fixing part 10 similar to FIG. A radial rail for guiding the fixed body 10 to be tested, 111 is a hinge attached to one end of the support 11 on the reference table 16, and is rotatable in the vertical direction (elevation direction), 112 is the support 11 A rod 12 ′ is provided on the end opposite to the hinge 111 to which is attached, and protrudes in a direction perpendicular to the longitudinal direction of the support portion 11. A pulley 12 ′ is a pulley for changing the moving radius (the variation of the moving radius in FIG. 1). (Corresponding to the transmission part 12), 12a is a radial driving force for moving the DUT 10 on the radial rail 110 downward (origin direction) or by moving the pulley 12 'upward. The transmission yarn 12b is a drive for rotating the pulley 12 '. Transmitting yarn 120 is radial drive unit.

  13 is a vertical portion similar to FIG. 1, 14 ′ is a pulley for changing the elevation angle (θ) of the DUT of the DUT fixing portion 10 (corresponding to the elevation change transmitting portion 14 in FIG. 1), and 14a is a moving One end is connected to a rod 112 attached to the radial rail 110, and the other end is connected to a counterweight (weight) 14b engaged with a pulley 14 '. A driving force transmission yarn 14b is a counterweight, and 14c is a counterweight 14'. A driving force transmission yarn 140 for driving the elevating angle 140 is an elevation angle driving unit. 15 ′ is a rotating unit (corresponding to the azimuth variation transmitting unit 15 in FIG. 1) driven to rotate the reference table 16 including the radial rail 110 and the vertical unit 13 as a whole to an azimuth angle, and 15a is a rotating unit 15. A driving force transmission yarn 150 for rotating 'is an azimuth rotation driving unit.

  FIG. 3 shows the connection configuration of the radial rail and the DUT fixing portion. In this example, as shown in FIG. 3A, the radial rail 110 is provided with a taper-type groove (groove that expands toward the inside) 110a at the center in the width direction, and the lower part of the DUT 10 is As shown in FIG. 3B, a trapezoidal lower portion that fits into the tapered groove 110a is provided. Reference numeral 10a denotes a tag-like object insertion port for inserting (accommodating) an RFID tag, and 10b denotes an RFID tag accommodated in the tag-like object insertion port 10a transmits and receives radio waves to and from the antenna (17 in FIG. 2). The central window 10c is fixed to the DUT by fixing one end to the triangular base of the DUT fixing portion 10 (the portion fitted in the tapered groove 110a) and the other end fixed to the hinge 111 side. It is a rubber (string) for radial direction origin tension that exerts a force that pulls the portion 10 toward the reference base 16 side.

  FIG. 4 shows a detailed configuration of the DUT fixing portion. FIG. 4A is a side view, and a tag-like device under test object insertion port 10a is provided as shown in the figure, and an RFID tag as a device under test is inserted into this portion. (b) is a rear view, a cross-sectional view taken along the center line A-A 'is shown in (c), and the center window 10b is arranged as shown.

  In the configuration of FIG. 2, when the moving radius (r) is changed, a moving radius control signal a from the drive system control device (3 in FIG. 1) is supplied to the moving radius drive portion 120, whereby the moving radius drive portion 120. Is driven, the pulley 12 'rotates when the driving force transmission yarn 12b is driven in any direction, and the driving force transmission yarn 12a is wound around the pulley 12' or released depending on whether the winding is released. The value of the moving radius (r) changes as the test body fixing part 10 moves upward or downward along the tapered groove 110a shown in FIG. In addition, when moving downward, the tension of the radial-direction origin tension rubber 10c shown in FIG. 3 works.

  When the elevation angle (θ) is changed, an elevation angle control signal b is supplied from the drive system controller (3 in FIG. 1) to the elevation angle drive unit 140, so that the pulley 14 ′ is rotated when the elevation angle drive unit 140 is driven. When the driving force transmission yarn 14a can be moved forward with the help of the counterweight 14b, the radial rail 110 is pulled up by the rod 112 around the hinge 111 and the elevation angle (θ) increases, and the pulley 14 ′ is rotated in the reverse direction. As a result, the radial rail 110 moves downward to decrease the elevation angle (θ).

  When the azimuth angle (φ) is changed, the azimuth angle rotation drive unit 150 is driven by supplying the azimuth angle control signal c to the azimuth angle rotation drive unit 150 from the drive system controller (3 in FIG. 1). The driving force transmission yarn 15a moves to rotate the rotating portion 15 ′. As the rotating portion 15 'rotates clockwise or counterclockwise, the antenna 17 fixed thereon rotates to change the azimuth angle.

  FIG. 5 shows the configuration of an embodiment of the RFID evaluation system. In the figure, 1 is a positioning device (positioner) having the configuration shown in FIG. 2, 20 and 21 are the test device 2 of FIG. 1, 20 is an evaluation / storage device, and 20a is a test program for performing the evaluation. The evaluation scheduler 20b includes a test result storage device that stores test results. 21 is a test wave transmission / reception device, 21a is a control device for controlling the transmission (transmission) and detection (reception) of the test wave under the control of the evaluation / storage device 20, and 21b is a test wave from the antenna 17 to the RFID tag. Is a test wave transmission / detection device that detects the signal of the antenna 17 that has received the radio wave responding from the RFID tag. Reference numeral 3 denotes a drive system controller that drives the radial drive unit 120, the elevation drive unit 140, and the azimuth rotation drive unit 150 according to a signal indicating the position from the evaluation / storage device 20. When the radial drive unit 120, the elevation drive unit 140, and the azimuth rotation drive unit 150 are driven, the corresponding radial drive yarn, elevation drive yarn, and azimuth drive yarn move, so that the DUT is fixed. Positioned at the specified position.

  FIG. 6 is a control flow of RFID evaluation. Based on the command of the evaluation / storage device 20 in the evaluation system of FIG. 5, the radial drive unit 120, the elevation drive unit 140, and the azimuth rotation drive from the drive system control device 3 This is executed by driving the unit 150.

  First, φ0 is set as the initial azimuth (S1 in FIG. 6), then θ0 is set as the initial elevation angle (S2), and r0 is set as the initial measurement point (radial distance) (S3). When each driving unit of the positioning device (1 in FIGS. 1 and 2) is driven to the set initial position, the measurement is executed in a state in which the test object fixing unit is set to the initial setting position (FIG. 6 S4). The detailed contents of this measurement are shown in FIG. Next, the reading rate obtained by the measurement executed in step S4 (repeatedly executing the same test many times) (the number of signals correctly received with respect to the number of read signals transmitted to the RFID tag of the device under test) Is over a predetermined rate (for example, 90%) (S5 in FIG. 6), if it is over, the radial distance is updated to ri + 1 (S6 in the same), and if not over (more than this, the radial If it is meaningless to change the value, it is determined whether the next elevation angle is the final elevation angle (S7 in FIG. 6).

  If it is determined that the angle is not the final elevation angle, the elevation angle is updated to θi + 1 (S8), and the initial measurement point (radial radius) r0 is set to perform measurement (S4). Thus, for the updated elevation angle, the measurement operation in S4 and the update of the radial distance are repeated by S5 and S6. If the reading rate does not reach the predetermined value in S5, the next elevation angle is updated and the same processing is repeated. When the elevation angle is reached, it is determined whether or not the final azimuth angle is reached (S9 in FIG. 6). If the final azimuth angle is not reached, the next azimuth angle φi + 1 is updated (S10) and the initial elevation angle θ0 is set. (S2), the same processing, that is, the processing of S3, S4, S5, S6, S4, S5,..., S5, S7, S8,. When it is determined that the final azimuth has been reached, the process ends.

  FIG. 7 is a measurement processing flow, which is executed in S4 of FIG. When started, a test wave compliant with the protocol (protocol determined according to the type of the RFID tag) is transmitted (S40 in FIG. 7), and a response wave from the RFID tag is received for the time compliant with the protocol. (S41). Next, test wave transmission conditions and reception wave recording and determination are performed (S42 in FIG. 7). In this case, a determination is made as to whether the identification code received from the RFID tag matches the set identification code (whether it has been received correctly). Thereafter, it is determined whether or not the designated number of tests have been repeated (S43 in FIG. 7). If the designated number has not been reached, the test wave transmission is turned off for a certain period of time (S44), and the process returns to step S40. , End this measurement.

It is a figure which shows the principle structure of this invention. It is a figure which shows the structure of the Example of the positioning device of a to-be-tested object. It is a figure which shows the connection structure of a radial direction rail and a to-be-tested object fixing | fixed part. It is a figure which shows the detailed structure of a to-be-tested object fixing | fixed part. It is a figure which shows the structure of the Example of RFID evaluation system. It is a figure which shows the control flow of RFID evaluation. It is a figure which shows the processing flow of a measurement.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Positioning device 10 Test object fixing | fixed part 11 Support part 110 Radial direction rail 111 Hinge 12 Radial fluctuation transmission part 120 Radial drive part 13 Vertical part 14 Elevation angle fluctuation transmission part 140 Elevation angle drive part 15 Azimuth angle fluctuation transmission part 150 Azimuth Angular rotation drive unit 16 Reference table 17 Antenna 2 Test device 3 Drive system control device

Claims (4)

A long and thin plate-shaped radial rail that movably supports the DUT holding the RFID (Radio Frequency Identification) tag to be evaluated, and the DUT to be moved back and forth on the radial rail And an elevation angle that drives the radial rail in the vertical direction by rotating the radial rail up and down with respect to a horizontal plane with the base at one end of the radial rail as the origin. A positioning device comprising: a drive unit; and an azimuth angle drive unit that drives the radial rail to rotate to an arbitrary azimuth angle about a vertical part perpendicular to a horizontal plane located at the origin.
An antenna for transmitting a test radio signal to the RFID tag and receiving a radio signal transmitted from the RFID tag is provided at the origin position,
For each combination of each value of the radius, elevation angle, and azimuth, the antenna transmits a radio signal to the RFID tag and receives a radio signal received from the RFID tag. An RFID tag evaluation system comprising: a test apparatus that evaluates by changing an azimuth angle. In claim 1,
A taper-type groove is provided at the center on the radial rail, and a base having a shape that fits into the taper-type groove is provided at a lower portion of the test object fixing portion, and the device under test is formed along the taper-type groove. An RFID tag evaluation system characterized in that a moving force is changed by driving a body fixing portion with a driving force transmission yarn by the moving radius driving portion. In either claim 1 or 2,
The connecting a base of radial rails rotatable up and down by the reference base and the hinge, between the other end to the vertical portion of the radial rails connected by the driving force transmission fiber, the driving force transmitting yarn An RFID tag evaluation system which is driven by the elevation angle drive unit to change the elevation angle of the radial rail. In any one of Claims 1 thru | or 3,
The control device of the test apparatus sets the initial azimuth angle, initial elevation angle, and initial radius, performs measurement by test wave transmission, response wave reception, and determination, and determines the predetermined reading rate (success rate) by the determination. ) If this is the case, increase the moving radius by a minute value and execute the above measurement. If the reading rate does not reach the specified value, update the elevation angle and set the initial moving radius to execute the measurement. Then, the RFID tag evaluation system is characterized in that the azimuth angle is updated and the same measurement is repeated.

Images