SYSTEM AND METHOD FOR TESTING IOT TAGS

Abstract

A system and a method for testing a wireless tag that has an antenna for wireless communication and employs a low energy wireless communication protocol. The system includes a near field antenna; and a fixture for positioning the wireless tag to be tested so that the at least one antenna for wireless communication of the at least one wireless tag to be tested is within a near field of the near field antenna of the system; wherein when the wireless tag is positioned by the fixture, it is within an at least a partly open chamber. The method comprises supplying, via the near field antenna of the system, a test signal for receipt by the antenna of the wireless tag; and comparing a received signal strength of a response from the wireless tag in response to the test signal to an expected benchmark.

Claims

1. A system for testing a wireless tag that has at least one antenna for wireless communication and employs at least one low energy wireless communication protocol, the system comprising: a near field antenna; and a fixture for positioning the wireless tag so that the at least one antenna for wireless communication of the wireless tag is within a near field of the near field antenna of the system; wherein when the wireless tag is positioned by the fixture, the wireless tag is within an at least a partly open chamber.

2. The system as defined in claim 1, wherein testing is performed when the at least one antenna for wireless communication of the wireless tag is within a near field produced by the near field antenna of the system.

3. The system as defined in claim 2, wherein the testing of the wireless tag within a near field produced by the near field antenna of the system is indicative of expected behavior of the wireless tag when it is deployed in a far field of a unit with which it is to communicate under operating conditions.

4. The system as defined in claim 2 wherein a full radio frequency (RF) path of the wireless tag is tested while the wireless tag is within a near field produced by the near field antenna of the system.

5. The system as defined in claim 1, wherein the chamber is at least partly open when testing is performed.

6. The system as defined in claim 1, wherein during testing, the near field antenna of the system is used to both energize and communicate with the wireless tag in order to test it.

7. The system as defined in claim 1, wherein, during testing, the near field antenna of the system and the wireless tag are less than 3 cm apart.

8. A system for performing dynamic testing of one or more wireless tags each of which has at least one antenna for wireless communication and employs at least one low energy wireless communication protocol, the system comprising: a near field antenna; and a moving surface for positioning each of the wireless tags to be tested so that the at least one antenna for wireless communication of the wireless tag to be tested is positioned to be within a near field of the near field antenna of the system; wherein, when the wireless tag to be tested is positioned by the moving surface to be within the near field of the near field antenna of the system, the wireless tag to be tested is within an at least a partly open chamber.

9. The system as defined in claim 8 wherein moving surface is substantially not conductive.

10. The system as defined in claim 8, wherein the near field antenna is located below the moving surface.

11. The system as defined in claim 8, wherein the moving surface is a conveyor belt.

12. The system as defined in claim 8, wherein the system further comprises the partly open chamber.

13. The system as defined in claim 8, wherein each tag being tested is tested when the at least one antenna for wireless communication of the tag being tested is moved by the moving surface to be located within a near field produced by the near field antenna of the system.

14. The system as defined in claim 13, wherein the testing of each respective one of the wireless tags when tested within a near field produced by the near field antenna of the system is indicative of expected behavior of the respective wireless tag when it is deployed in a far field of a unit with which it is to communicate under operating conditions.

15. The system as defined in claim 13, wherein a full radio frequency (RF) path of each wireless tag being tested is tested while each wireless tag is within a near field produced by the near field antenna of the system.

16. The system as defined in claim 8, further comprising a processor, the processor controlling the movement of the moving surface to be coordinated with the testing of each of the tags sequentially.

17. The system as defined in claim 16, wherein the processor controls the movement of the moving surface and the testing of each of the tags based on an analysis of a charging time of a capacitor of at least one of the tags and data rate for communication supported by at least one of the tags.

18. A method for use in connection with a system for testing at least one wireless tag that has at least one antenna for wireless communication and employs at least one low energy wireless communication protocol, the system having: a near field antenna; and a fixture for positioning the at least one wireless tag to be tested so that the at least one antenna for wireless communication of the at least one wireless tag to be tested is within a near field of the near field antenna of the system; wherein when the wireless tag to be tested is positioned by the fixture, the wireless tag is within an at least a partly open chamber; the method comprising: supplying, via the near field antenna of the system, a test signal for receipt by the at least one antenna of the wireless tag; and comparing a received signal strength of a response from the wireless tag in response to the test signal to an expected benchmark.

19. The method as defined in claim 18, wherein the method further comprises sequentially positioning each of a plurality of wireless tags as the at least one wireless tag.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0030] The foregoing and other objects, features, and advantages of the disclosed embodiments will be apparent from the following detailed description taken in conjunction with the accompanying drawings.

[0031] FIG. 1 is a schematic diagram of an illustrative IoT tag;

[0032] FIG. 2 is a schematic diagram of a prior art tester configured to test the functionality of IoT tags;

[0033] The foregoing and other objects, features, and advantages of the disclosed embodiments will be apparent from the following detailed description taken in conjunction with the accompanying drawings.

[0034] FIG. 1 is a schematic diagram of an illustrative IoT tag;

[0035] FIG. 2 is a schematic diagram of a prior art tester configured to test the functionality of IoT tags;

[0036] FIG. 3 shows an embodiment of a tester that avoids the difficulties of the prior art tester;

[0037] FIG. 4 shows an arrangement which allows for the dynamic testing of IoT tags using the tester of FIG. 3; and

[0038] FIG. 5 provides a perspective view of the arrangement of FIG. 4.

DETAILED DESCRIPTION

[0039] The embodiments disclosed by the invention are only examples of the many possible advantageous uses and implementations of the innovative teachings presented herein. In general, statements made in the specification of the present application do not necessarily limit any of the various claimed embodiments. Moreover, some statements may apply to some inventive features but not to others. In general, unless otherwise indicated, singular elements may be in plural and vice versa with no loss of generality. In the drawings, like numerals refer to like parts through several views.

[0040] Problems with testing wireless devices, e.g., wireless tags, that employ protocols such as Bluetooth, BLE, and other low energy wireless communication protocols, can be mitigated by apparatus for testing such a tag that has at least one antenna for wireless communication, wherein the testing apparatus comprises a near field antenna and a fixture for positioning the device to be tested so that the at least one antenna for wireless communication of the device to be tested is within the near field of the near field antenna; and wherein when the wireless device to be tested is positioned by the fixture, it is within an at least a partly open chamber.

[0041] FIG. 1 is a schematic diagram of an illustrative IoT tag 100 utilized with the various embodiments for testing such IoT tags. The IoT tag 100 includes an integrated circuit (IC, or chip) 120 and at least one antenna 110-1, 110-2 placed on an inlay 105. In an embodiment, the inlay 105 is a single layer inlay that includes the integrated circuit 120 connected to the at least one antenna 110-1, 110-2 and may be mounted on a substrate (not shown). The substrate is a single layer material, which may be a single metal layer or any appropriate integrated circuit mounting material, such as a printed circuit board (PCB), silicon, flexible printed circuits (FPC), low temperature co-fired ceramic (LTCC), polyethylene terephthalate (PET), Polyimide (PI), paper, and the like.

[0042] In an example embodiment, the IoT tag 100 includes a pair of antennas 110-1 and 110-2 that are etched within the inlay 105. The first antenna 110-1 is utilized to harvest energy from ambient RF signals and the second antenna 110-2 is utilized to communicate, e.g., transmit and receive, signals, such as Bluetooth Low Energy (BLE) signals. Each antenna 110-1, 110-2 may be of a type including a loop antenna, a big loop with two feeds, a dipole antenna with two transformer feeds, and similar configurations. It should be noted that the transmitting antenna 110-2 may be utilized to harvest energy as well. Further, in some configurations, a plurality of antennas may be used to harvest energy, each of which is designed to receive signals of different frequencies.

[0043] In an embodiment, the IoT tag 100 also includes a capacitor 130 that may be realized as an on-die capacitor, an external passive capacitor, and the like. The energy harvesting functionality is performed by the integrated circuit 120.

[0044] In order to ensure that the IoT tag 100 can operate accurately, the harvesting frequency of the harvesting antenna 110-1 should be tested to determine if it falls within acceptable parameters that enable charging of the capacitor 130 within a predetermined timeframe. In an embodiment, the testing requires determining if each individual IoT tag 100 is capable of receiving signals, harvesting energy, charging a capacitor, and sending signals.

[0045] Because the IoT tag 100 is often configured to operate efficiently using a minimal amount of power available from energy harvesting, the effective operating frequency range of the IoT tag 100 is limited. Determining if a tag operates successfully within a set frequency range is crucial in evaluating whether a particular tag is capable of performing as desired.

[0046] The harvesting antenna 110-1 of the IoT tag 100 receives energy over RF signals at one or more frequency bands. Such bands are specific to the parameters of that tag, which include, but are not limited to, physical parameters such as antenna length, thickness, conductivity, resistivity, and antenna properties, such as gain, radiation pattern, beam width, polarization, impedance, and the like. It should be noted that even minute differences or shifts between the parameters of two antennas may result in a different harvesting frequency.

[0047] Based on the harvesting frequency, the harvesting antenna 110-1 of an IoT tag 100 is tuned to a frequency band where the IoT tag can most efficiently receive and transform RF signals received over that band into a DC voltage. In an embodiment, the DC voltage is stored on the capacitor 130, or on a similar power storage device.

[0048] The energy E on the capacitor 130 is related to the DC voltage V by the following equation: E=1/2CV.sup.2, where C is the capacitance of the capacitor. As discussed above, the inlay 105 of the IoT tag 120 may include multiple antennas, where more than one antenna may be configured as a separate harvester. In an embodiment, each harvester is connected to a separate storage capacitor, while in a further embodiment, a single storage capacitor is common to multiple harvesters, allowing for an increased shared storage capacity for the IoT tag 100.

[0049] FIG. 3 shows an embodiment of a tester 300 that avoids the difficulties of the prior art tester 200 by performing the testing when communication antenna 110-2 of IoT tag 100 is within the near field of antenna 301. In some embodiments, antenna 301 is configured to specifically be a near field antenna. During the testing, antenna 301 is arranged to be near or under IoT tag 100. Near field antenna 301 is used to both energize and communicate with our IoT 100 in order to test it.

[0050] In one embodiment, near field antenna 301 and IoT 100 are placed quite close to each other during the testing. Although this is not shown in FIG. 3, it can be seen in FIGS. 4 and 5, and as described hereinbelow. Reducing the distance and power as much as possible helps to avoid neighbor or nearby tags inadvertently also communicating with the tester 300 and thus interfering with the testing. In one illustrative embodiment, near field antenna 300 and IoT 100 are less than ˜3 cm apart. In embodiments, testing of IoT tag 100 in the near field of antenna 300 enables prediction of the behavior of IoT tag 100 when deployed in the far field of a unit with which it is to communicate with when deployed in the field. Advantageous, the near filed approach enables using lower power and smaller size testing infrastructure than is otherwise needed, e.g., as in FIG. 2. Furthermore, in embodiments of the invention the full radio frequency (RF) path may be tested.

[0051] FIG. 4 shows arrangement 400 which allows for the dynamic testing of IoT tags 100 using tester 300. Dynamic testing involves testing IoT tags 100 as they pass close to near field antenna 301. In an embodiment, dynamic testing includes placing multiple cured IoT tags 100 on a moving surface 470, such as a conveyor belt, where they pass by near field antenna 301. For example, as each IoT tag 100 passes over near field antenna 301 it is tested. In this embodiment, tester 300 is configured to synchronize the test flow based on analyzing the charging times of a capacitor and the data rate.

[0052] Note that because the testing is being done in the near field, the testing need not be done in a fully shielded environment, as can be seen from FIGS. 4 and 5. FIG. 4 shows various shielding portions 405, which are made of conductive metal, which form a partially closed chamber around near field antenna 301. An opening in the chamber 409 formed by the various shielding portions is such that radio waves can pass from near field antenna 301 to IoT tag 100 that is under test, e.g., directly over near field antenna 101. In embodiments of the invention, conveyor belt is not conductive so as to minimize interference of the communication between near field antenna 301 with IoT tag 100. A controller (not shown) may synchronize the movement of moving surface 470 and the testing process, e.g., the signals transmitted by near field antenna 301.

[0053] FIG. 5 provides a perspective view of arrangement 400 of FIG. 4.

[0054] various embodiments disclosed herein can be implemented as hardware, firmware, software, or any combination thereof. Moreover, the software is preferably implemented as an application program tangibly embodied on a program storage unit or computer readable medium consisting of parts, or of certain devices and/or a combination of devices. The application program may be uploaded to, and executed by, a machine comprising any suitable architecture. Preferably, the machine is implemented on a computer platform having hardware such as one or more central processing units (“CPUs”), a memory, and input/output interfaces. The computer platform may also include an operating system and microinstruction code. The various processes and functions described herein may be either part of the microinstruction code or part of the application program, or any combination thereof, which may be executed by a CPU, whether or not such a computer or processor is explicitly shown. In addition, various other peripheral units may be connected to the computer platform such as an additional data storage unit and a printing unit. Furthermore, a non-transitory computer readable medium is any computer readable medium except for a transitory propagating signal.

[0055] As used herein, the phrase “at least one of” followed by a listing of items means that any of the listed items can be utilized individually, or any combination of two or more of the listed items can be utilized. For example, if a system is described as including “at least one of A, B, and C,” the system can include A alone; B alone; C alone; A and B in combination; B and C in combination; A and C in combination; or A, B, and C in combination.

[0056] All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the principles of the disclosed embodiment and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, aspects, and embodiments of the disclosed embodiments, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure.