TDMA measurement device and TDMA measurement method

Abstract

To provide a TDMA measurement apparatus and a TDMA measurement method configured to quickly investigate the cause when an expected measurement result cannot be obtained, while properly determining likelihood of measurement results of transmitting / receiving characteristics under OTA environment of a TDMA terminal in light of radio wave conditions in a bandwidth of a measurement target frequency band.SOLUTION: In a TDMA terminal measurement apparatus 1, a test control unit 28 includes: a test execution control unit 28a which executes transmission performance test for measuring transmission characteristics of DUT, which is a TDMA terminal, and receiving performance test for measuring receiving characteristics; an interference signal detection unit 24 which detects an interference signal for a frequency band in a bandwidth of a measurement target frequency band during the transmission performance test or the receiving performance test; and an interference warning unit 28b which issues, when an interference signal is detected, a warning about detection of the interference signal in association with a result of measuring the transmission characteristics or a result of measuring the receiving characteristics of the DUT 100.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a TDMA measurement device and a TDMA measurement method for measuring transmission and reception characteristics of a Time Division Multiple Access (TDMA) terminal in an Over The Air (OTA) environment. [Background technology]

[0002] Bluetooth (registered trademark) is known as one of the communication standards (wireless standards) for short-range wireless communication that consumes little power and handles a relatively small amount of data. Since Bluetooth has advantages such as low power consumption and little data delay, it is adopted as a wireless communication unit for many digital devices that require long-term use and small data delay, such as smartphones, PCs, and their peripheral devices (keyboards, mice, wireless earphones, etc.) Due to the above-mentioned advantages of Bluetooth, various digital devices (hereinafter referred to as Bluetooth terminals) equipped with a wireless communication unit that performs short-range wireless communication according to the Bluetooth communication standard have been actively produced in recent years.

[0003] At manufacturing plants for Bluetooth devices, performance tests are conducted on the wireless communication unit (short-range wireless communication unit) of the Bluetooth device to measure the output level and signal quality of the transmitted radio waves defined for each communication standard and determine whether or not they meet specified standards.

[0004] In the above-mentioned performance test, a method is known in which a Bluetooth terminal as a device under test (DUT) is housed in an electromagnetic shielding box with its short-range wireless communication unit and a test antenna for transmitting and receiving wireless signals spatially coupled, and the transmission and reception characteristics of the DUT are measured in a wireless (OTA) environment.

[0005] On the other hand, with regard to measurements relating to the transmission and reception characteristics of Bluetooth terminals, a technique for measuring and displaying the power of signals in all channels has been conventionally known (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2003-283443 A Summary of the Invention [Problem to be solved by the invention]

[0007] By the way, in Bluetooth communication, a hopping method is adopted as a spreading method to avoid concentrating energy in a specific band and to reduce interference from other communications. In this method, the transmitter and receiver communicate by switching the frequency at high speed according to a hopping pattern agreed upon by the transmitter and receiver. Bluetooth terminals also adopt the TDMA method as a multiplexing method, which divides one frequency band by time and allocates channels, so they can be called TDMA terminals.

[0008] When measuring the transmission / reception characteristics of TDMA terminals such as Bluetooth terminals in an OTA environment, for example, depending on the shielding performance of the electromagnetic shielding box or the tightness of the lid of the electromagnetic shielding box, electromagnetic waves entering the electromagnetic shielding box from the surroundings during measurement may become interference signals and affect the measurement results. In conventional measurement methods for TDMA terminals on production lines, no display technology was established for checking the interference state caused by such interference signals.

[0009] As an example of this type of conventional display technology, for example, the conventional communication status measurement method described in Patent Document 1 employs a technology that measures the transmission power of all channels of the Bluetooth communication standard and displays the transmission power of each channel in a bar graph. Even if the display technology related to this conventional communication status measurement method is adopted in a mass production line of Bluetooth terminals, the person measuring (user) in the mass production line will only be able to recognize whether the transmission power of each channel exceeds the standard value (measurement result = OK) or does not reach the standard value (measurement result = NG) as a measurement result related to the transmission and reception characteristics of the Bluetooth terminal.

[0010] Thus, in the past, when it came to measuring the transmission and reception characteristics of TDMA terminals in an OTA environment, there was no means of grasping the degree of certainty behind the measurement results, whether they were OK or NG, and this reduced the certainty of the measurement results.

[0011] The reliability of the measurement results can be improved by understanding the radio interference situation for measurements in an OTA environment. For example, the frequency band used by Bluetooth terminals is fixed at 2.4 GHz, so if the radio interference situation due to radio waves having frequencies within the measurement target frequency band can be understood, it becomes easier to judge the reliability of the measurement results.

[0012] However, conventional measurement methods for TDMA terminals such as Bluetooth terminals did not have the means to grasp the presence of interference signals, either within or outside the frequency band to be measured. Therefore, conventional measurement methods for TDMA terminals inevitably result in a decrease in the accuracy of the measurement results as described above. In addition, when the measurement results are NG, it often takes a long time to determine the cause, for example, whether the shielding box is not properly closed or the DUT itself is faulty.

[0013] The present invention has been made to solve the above-mentioned problems in the conventional technology, and aims to provide a TDMA measurement device and a TDMA measurement method that can correctly judge the reliability of the measurement results of the transmission and reception characteristics of a TDMA terminal in an OTA environment in light of the radio wave conditions within the frequency band to be measured, and can also quickly identify the cause when the expected measurement results are not obtained. [Means for solving the problem]

[0014] In order to solve the above problem, a TDMA measurement device according to claim 1 of the present invention is a TDMA measurement device that houses a TDMA terminal that performs short-range wireless communication by a time division multiple access (TDMA) system as an object under test (100) in an electromagnetic shielding box (50) and measures transmission characteristics and reception characteristics of the object under test in a wireless environment, and is characterized in that it comprises: a setting means (40) that sets measurement conditions including a measurement target frequency band; a test execution control means (28a) that executes a transmission performance test that measures the transmission characteristics and a reception performance test that measures the reception characteristics by performing short-range wireless communication with the object under test according to a predetermined test procedure; an interference signal detection means (24) that detects an interference signal exceeding a predetermined threshold output level for a frequency band within the measurement target frequency band set by the setting means during the execution of the transmission performance test or the reception performance test; and an interference warning means (28b) that issues a warning that the interference signal has been detected, in association with the measurement results of the transmission characteristics or the measurement results of the reception characteristics of the object under test, when the interference signal is detected by the interference signal detection means.

[0015] With this configuration, the TDMA measurement device according to claim 1 of the present invention can, for example, recognize an interference signal within the measurement frequency band when measuring the transmission and reception characteristics (transmission characteristics and reception characteristics) of a TDMA terminal as a measurement target in a wireless (OTA) environment by issuing a warning. It is possible to suggest to the person making the measurement (user) that the measurement result of the transmission and reception characteristics associated with the warning may be affected by an interference signal within the band, and this allows the user to judge the accuracy of the measurement result in light of the radio wave conditions within the measurement target frequency band, and the accuracy of the measurement result can be expected to improve. Also, even when the expected measurement result is not obtained (an uncertain measurement result is obtained), it is possible to quickly respond to the cause investigation based on the possibility of the influence of the interference signal.

[0016] In addition, in the TDMA measurement device according to claim 2 of the present invention, the test execution control means may be configured to execute the transmission performance test of transmitting a transmission command of a desired transmission signal to the device under test, and measuring the transmission characteristics based on a measurement result of the transmission signal transmitted by the device under test in response to the transmission command, and the reception performance test of transmitting a reception command and a confirmation test signal to the device under test, and measuring the reception characteristics based on a reception status notification transmitted by the device under test upon receiving the reception test signal.

[0017] With this configuration, the TDMA measurement device of claim 2 of the present invention measures the transmission level, signal quality, or receiving sensitivity of the radio waves of a TDMA terminal, and when an interference signal is detected within the frequency band to be measured during the measurement, it issues a warning to the effect that an interference signal has been detected in association with the measurement results, thereby informing the user that the measured transmission level or receiving sensitivity of the radio waves may be affected by an interference signal, which is expected to improve the reliability of the measurement results, and also makes it possible to quickly respond to the investigation of the cause when an uncertain measurement result is obtained.

[0018] The TDMA measurement device according to claim 3 of the present invention The TDMA measurement device accommodates a TDMA terminal that performs short-distance wireless communication by a time division multiple access (TDMA) system as an object under test (100) in an electromagnetic shielding box (50) and measures transmission characteristics and reception characteristics of the object under test in a wireless environment, the device comprising: setting means (40) for setting test conditions including a measurement target frequency band; test execution control means (28a) for executing a transmission performance test that measures the transmission characteristics and a reception performance test that measures the reception characteristics by performing short-distance wireless communication with the object under test in accordance with a predetermined test procedure; and during execution of the transmission performance test or the reception performance test, setting a predetermined threshold output level for a frequency band within the measurement target frequency band set by the setting means. and an interference warning means (28b) for, when the interference signal is detected by the interference signal detection means, issuing a warning to the effect that the interference signal has been detected in association with the measurement results of the transmission characteristics or the measurement results of the reception characteristics of the device under test. The test execution control means executes the transmission performance test in which a transmission command for a desired transmission signal is transmitted to the device under test, and the transmission characteristics are measured based on the measurement results of the transmission signal transmitted by the device under test in response to the transmission command, and the reception performance test in which a reception command and a reception test signal are transmitted to the device under test, and the reception characteristics are measured based on a reception status notification transmitted by the device under test upon receiving the reception test signal.The interference signal detection means includes an ideal signal generation unit (24a) that receives a demodulated signal (S1) generated by reception processing of the transmission signal from the device under test in the transmission performance test or by reception processing of a signal received from the periphery when the reception test signal is transmitted to the device under test in the reception performance test, and generates an ideal signal (Si) of the demodulated signal based on the demodulated signal, and an interference signal capture unit (24c) that captures a signal (Sitf) obtained by subtracting the ideal signal from the demodulated signal as the interference signal. It is characterized by:

[0019] With this configuration, the TDMA measurement device according to claim 3 of the present invention Place The present invention has a simple configuration including an ideal signal generating section and an interference signal acquiring section, and is therefore capable of reliably detecting interference signals within the frequency band to be measured.

[0020] The TDMA measurement device according to claim 4 of the present invention The TDMA measurement device accommodates a TDMA terminal that performs short-distance wireless communication by a time division multiple access (TDMA) system as an object under test (100) in an electromagnetic shielding box (50) and measures transmission characteristics and reception characteristics of the object under test in a wireless environment, the device comprising: setting means (40) for setting test conditions including a measurement target frequency band; test execution control means (28a) for executing a transmission performance test that measures the transmission characteristics and a reception performance test that measures the reception characteristics by performing short-distance wireless communication with the object under test in accordance with a predetermined test procedure; and during execution of the transmission performance test or the reception performance test, setting a predetermined threshold output level for a frequency band within the measurement target frequency band set by the setting means. and an interference warning means (28b) for, when the interference signal is detected by the interference signal detection means, issuing a warning to the effect that the interference signal has been detected in association with the measurement results of the transmission characteristics or the measurement results of the reception characteristics of the device under test. The test execution control means executes the transmission performance test in which a transmission command for a desired transmission signal is transmitted to the device under test, and the transmission characteristics are measured based on the measurement results of the transmission signal transmitted by the device under test in response to the transmission command, and the reception performance test in which a reception command and a reception test signal are transmitted to the device under test, and the reception characteristics are measured based on a reception status notification transmitted by the device under test upon receiving the reception test signal. The interference signal detection means includes a reference signal holding unit (24e) that receives a demodulated signal (S1) generated by reception processing of the transmission signal from the device under test in the transmission performance test or by reception processing of a signal received from the periphery when the reception test signal is transmitted to the device under test in the reception performance test, and holds the demodulated signal (S1) as a reference signal (S11), and an interference signal capture unit (24g) that captures a signal (Sitf) that is a difference between different on-intervals or between different off-intervals of the demodulated signal and the reference signal as the interference signal. It is characterized by:

[0021] With this configuration, the TDMA measurement device of claim 4 of the present invention can more easily and reliably detect interference signals from the difference between each section (on section or off section) of the input demodulated signal and a section other than the above-mentioned sections of the reference signal.

[0022] The TDMA measurement device according to claim 5 of the present invention The TDMA measurement device accommodates a TDMA terminal that performs short-distance wireless communication by a time division multiple access (TDMA) system as an object under test (100) in an electromagnetic shielding box (50) and measures transmission characteristics and reception characteristics of the object under test in a wireless environment, the device comprising: setting means (40) for setting test conditions including a measurement target frequency band; test execution control means (28a) for executing a transmission performance test that measures the transmission characteristics and a reception performance test that measures the reception characteristics by performing short-distance wireless communication with the object under test in accordance with a predetermined test procedure; and during execution of the transmission performance test or the reception performance test, setting a predetermined threshold output level for a frequency band within the measurement target frequency band set by the setting means. and an interference warning means (28b) for, when the interference signal is detected by the interference signal detection means, issuing a warning to the effect that the interference signal has been detected in association with the measurement results of the transmission characteristics or the measurement results of the reception characteristics of the device under test. The test execution control means executes the transmission performance test in which a transmission command for a desired transmission signal is transmitted to the device under test, and the transmission characteristics are measured based on the measurement results of the transmission signal transmitted by the device under test in response to the transmission command, and the reception performance test in which a reception command and a reception test signal are transmitted to the device under test, and the reception characteristics are measured based on a reception status notification transmitted by the device under test upon receiving the reception test signal.The electromagnetic shielding box accommodates a Bluetooth terminal that communicates according to the Bluetooth communication standard as the TDMA terminal, and the test execution control means performs the transmission performance test and the reception performance test by using the Bluetooth terminal as the device under test and communicating with the device under test according to the Bluetooth communication standard in accordance with the test procedure. It is characterized by:

[0023] With this configuration, the TDMA measurement device according to claim 5 of the present invention can be applied to measuring the transmission characteristics and reception characteristics of a Bluetooth terminal that communicates according to the Bluetooth communication standard in an OTA environment. When an interference signal is measured within the frequency band to be measured, a warning to that effect is issued, so that it is easy to determine whether the measurement results related to the transmission characteristics and reception characteristics of the Bluetooth terminal displayed together are reliable. In addition, when a warning is issued to the effect that an interference signal has been detected, even in a situation where an unreliable measurement result is obtained, it becomes easier to isolate the cause as being due to an interference signal rather than an abnormality in the Bluetooth terminal.

[0024] The TDMA measurement device according to claim 6 of the present invention a TDMA measurement device that accommodates a TDMA terminal that performs short-distance wireless communication by a time division multiple access (TDMA) system as an object under test (100) in an electromagnetic shielding box (50) and measures transmission characteristics and reception characteristics of the object under test in a wireless environment, the TDMA measurement device comprising: a setting means (40) for setting test conditions including a measurement target frequency band; a test execution control means (28a) for executing a transmission performance test that measures the transmission characteristics and a reception performance test that measures the reception characteristics by performing short-distance wireless communication with the object under test according to a predetermined test procedure; an interference signal detection means (24) for detecting an interference signal exceeding a predetermined threshold output level for a frequency band within the measurement target frequency band set by the setting means during the execution of the transmission performance test or the reception performance test; and an interference warning means (28b) for, when the interference signal is detected by the interference signal detection means, issuing a warning that the interference signal has been detected in association with the measurement results of the transmission characteristics or the measurement results of the reception characteristics of the object under test; The setting means sets, as the measurement target frequency band, a frequency band corresponding to each of a plurality of hopping target frequency channels allocated to the 2.4 GHz band defined by the Bluetooth communication standard, and the interference signal detection means measures the interference signal by setting, as a frequency band within the band, a predetermined frequency range above and below the frequency band corresponding to one of the plurality of frequency channels set by the setting means. It is characterized by:

[0025] With this configuration, the TDMA measurement device of claim 6 of the present invention can easily check the accuracy of the measurement results of the transmission characteristics and reception characteristics of a desired frequency channel among multiple frequency channels that are successively switched over in hopping communication by a Bluetooth terminal, and even if an unreliable measurement result is obtained, it becomes easy to identify the cause.

[0026] The TDMA measurement device according to claim 7 of the present invention a TDMA measurement device that accommodates a TDMA terminal that performs short-distance wireless communication by a time division multiple access (TDMA) system as an object under test (100) in an electromagnetic shielding box (50) and measures transmission characteristics and reception characteristics of the object under test in a wireless environment, the TDMA measurement device comprising: a setting means (40) for setting test conditions including a measurement target frequency band; a test execution control means (28a) for executing a transmission performance test that measures the transmission characteristics and a reception performance test that measures the reception characteristics by performing short-distance wireless communication with the object under test according to a predetermined test procedure; an interference signal detection means (24) for detecting an interference signal exceeding a predetermined threshold output level for a frequency band within the measurement target frequency band set by the setting means during the execution of the transmission performance test or the reception performance test; and an interference warning means (28b) for, when the interference signal is detected by the interference signal detection means, issuing a warning that the interference signal has been detected in association with the measurement results of the transmission characteristics or the measurement results of the reception characteristics of the object under test; The interference warning means displays, as the warning, an interference warning message (32) indicating that the interference signal has been detected and the reliability of the measurement result of the transmission characteristic or the reception characteristic has decreased, in addition to the measurement result of the transmission characteristic or the reception characteristic. It is characterized by:

[0027] With this configuration, the TDMA measurement device of claim 7 of the present invention warns the user that an interference signal has been measured by displaying an interference warning message added to the measurement result, making the user more aware that the measurement result may be affected by an interference signal, and making it possible to reliably determine the accuracy of the measurement result taking the interference into account.

[0028] In addition, the TDMA measurement device according to claim 8 of the present invention may further include spectrogram generation means (28c) for analyzing a detection result of the interference signal by the interference signal detection means and generating a spectrogram (35a) representing a distribution of the interference signal in terms of a relationship between frequency and signal strength and time based on the analysis result, and display control means (28d) for switching to the interference warning message and displaying the spectrogram in response to a predetermined switching command.

[0029] With this configuration, the TDMA measurement device according to claim 8 of the present invention can more easily grasp the accuracy of the measurement result in light of the distribution of interference signals within the measurement target frequency band in the displayed spectrogram. Also, by looking at the distribution of interference signals in the spectrogram, it becomes easier to investigate the cause when an uncertain measurement result is obtained.

[0030] In order to solve the above problem, the TDMA measurement method according to claim 9 of the present invention is 1 A TDMA measurement method for measuring transmission characteristics and reception characteristics of an object under test (100) in a wireless environment, using the TDMA measurement device described in the above, housing a TDMA terminal that performs short-range wireless communication by a time division multiple access (TDMA) system in an electromagnetic shielding box (50), and measuring the transmission characteristics and reception characteristics of the object under test (100), comprising a setting step (S2) for setting measurement conditions including a frequency band to be measured, and a test execution step for executing a transmission performance test for measuring the transmission characteristics and a reception performance test for measuring the reception characteristics by performing short-range wireless communication with the object under test according to a predetermined test procedure. The method includes a control step (S4 to S6, S20 to S22), an interference signal detection step (S7, S23) for detecting an interference signal exceeding a predetermined threshold output level for a frequency band within the measurement target frequency band set by the setting step while the transmission performance test or the reception performance test is being performed, and an interference warning step (S10, S26) for, if the interference signal is detected by the interference signal detection step, issuing a warning that the interference signal has been detected in association with the measurement results of the transmission characteristics or the measurement results of the reception characteristics of the device under test.

[0031] With this configuration, the TDMA measurement method according to claim 9 of the present invention can be 1When measuring the transmission and reception characteristics (transmission characteristics and reception characteristics) of a TDMA terminal as a measurement target in a wireless (OTA) environment using the TDMA measurement device described in the above, for example, if an interference signal is measured within the measurement frequency band, the user can be made aware of this by a warning. It is possible to suggest to the user that the measurement result of the transmission and reception characteristics associated with the warning may be affected by the interference signal within the band, and this allows the user to judge the accuracy of the measurement result in light of the radio wave conditions within the measurement target frequency band, and it is possible to expect an improvement in the accuracy of the measurement result. Also, even when the expected measurement result is not obtained (an uncertain measurement result is obtained), it is possible to quickly respond to the cause investigation based on the possibility of the influence of the interference signal. Effect of the Invention

[0032] The present invention can provide a TDMA measurement device and a TDMA measurement method that can correctly judge the accuracy of measurement results of the transmission and reception characteristics of a TDMA terminal in an OTA environment in light of the radio wave conditions within the frequency band to be measured, and can also quickly respond to investigation into the cause when expected measurement results are not obtained. [Brief description of the drawings]

[0033] [Figure 1] 1 is a diagram showing the overall configuration of a TDMA terminal measurement device according to a first embodiment of the present invention. [Diagram 2] 1 is a block diagram showing a functional configuration of a TDMA terminal measurement device according to a first embodiment of the present invention. [Diagram 3] 1 is a block diagram showing a functional configuration of an interference signal detection unit mounted in a measuring device of a TDMA terminal measurement device according to a first embodiment of the present invention. [Figure 4] 1 is a block diagram showing a functional configuration related to interference warning control of a TDMA terminal measurement device according to a first embodiment of the present invention. [Diagram 5] 5 is a flowchart showing an interference warning control operation when the TDMA terminal measurement device according to the first embodiment of the present invention measures transmission characteristics of a Bluetooth terminal. [Figure 6] 5 is a flowchart showing an interference warning control operation when the TDMA terminal measurement device according to the first embodiment of the present invention measures the reception characteristics of a Bluetooth terminal. [Figure 7] 5 is a flowchart showing an interference signal measurement process in an interference signal detection unit of the TDMA terminal measurement device according to the first embodiment of the present invention. [Figure 8] 8 is a timing chart of signals related to the interference signal measurement process shown in FIG. 7. [Figure 9] 1 is a diagram showing an example of a display of an interference warning message on a display screen of a transmission characteristic measurement result of a Bluetooth terminal in a TDMA terminal measurement device according to a first embodiment of the present invention. FIG. [Figure 10] FIG. 2 is a diagram showing one display form of a spectrogram when measuring a Bluetooth terminal with a TDMA terminal measurement device according to the first embodiment of the present invention. [Figure 11] 11 is an image diagram showing an example of a spectrogram image based on the interference signal detection result within the measurement target frequency range in the spectrogram shown in FIG. 10. FIG. [Figure 12] FIG. 11 is a block diagram showing a functional configuration of an interference signal detection unit mounted in a measuring device of a TDMA terminal measurement device according to a second embodiment of the present invention. [Figure 13] 10 is a flowchart showing an interference signal measurement process in an interference signal detection unit of a TDMA terminal measurement device according to a second embodiment of the present invention. [Figure 14] 14 is a timing chart of signals related to the interference signal measurement process shown in FIG. 13. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] Hereinafter, an embodiment of a TDMA measurement device and a TDMA measurement method according to the present invention will be described with reference to the drawings. In the embodiment of the present invention, a TDMA terminal performing short-distance wireless communication by the TDMA method is placed as DUT100 in an OTA environment, and a TDMA terminal measurement device 1 that measures the transmission characteristics and reception characteristics of the DUT100 will be described as an example. As the TDMA terminal serving as the DUT100, a Bluetooth terminal performing short-distance wireless communication (Bluetooth communication) according to the Bluetooth communication standard is assumed. In particular, in the embodiment of the present invention, the TDMA terminal measurement device 1 has an interference warning control function that warns when a radio wave situation within the frequency band to be measured, more specifically, an interference signal that may affect the measurement results of the transmission and reception characteristics within the above band, is detected, so that the reliability of the measurement results of the transmission and reception characteristics of the TDMA terminal serving as the DUT in an OTA environment can be correctly determined.

[0035] (First embodiment) As shown in FIG. 1, the TDMA terminal measurement device 1 according to the first embodiment of the present invention includes a measurement device 10 and an electromagnetic shielding box 50. The electromagnetic shielding box 50 has, for example, a rectangular parallelepiped shape with one side open, a housing body 51 having an internal space, and a lid 52 supported by the housing body 51 via a hinge part (not shown) and capable of opening and closing the opening. The housing body 51 and the lid 52 are made of a conductive metal such as iron, stainless steel, aluminum, copper, brass, or an alloy of these. A DUT holding part 53 for holding a DUT 100 and a test antenna 54 are provided inside the housing body 51, and a radio wave absorber is attached to the entire surface of the internal space. A box 55 is provided at a required position of the housing body 51. Box 55 may connect measuring instrument 10 and electromagnetic shielding box 50, for example, via coaxial cable 25a, and may send transmission commands, reception commands, etc. from test execution control unit 28 to DUT 100 housed in coaxial cable 25a and electromagnetic shielding box 50 via corresponding test signals and test antenna 54. As another example, box 55 may be USB-connected, for example, via USB cable 25b, so that transmission commands, reception commands, etc. from test execution control unit 28 can be connected via a control line, separate from coaxial cable 25a.

[0036] 1, the electromagnetic shielding box 50 accommodates a DUT 100 having a short-range wireless communication unit 110 and a test antenna 54 inside the box (internal space) while blocking (shielding) electromagnetic waves from entering the internal space from the outside, and provides an OTA test environment by spatially coupling the short-range wireless communication unit 110 of the DUT 100 with the test antenna 54 connected to a coaxial cable 25a via a box 55. In the internal space of the electromagnetic shielding box 50, the DUT 100 is held by a DUT holding unit 53.

[0037] In this way, TDMA terminal measuring device 1 accommodates DUT 100 within the space (internal space) of electromagnetic shielding box 50, inputs signals for various tests from measuring instrument 10 to DUT 100 in an OTA environment, receives signals output from DUT 100 in response to receiving those signals with measuring instrument 10, and measures the transmission and reception characteristics (transmission characteristics and reception characteristics) of DUT 100 for the received signals.

[0038] The DUT 100 is a digital device such as a smartphone or a PC, and is a Bluetooth-equipped device equipped with a Bluetooth communication unit that performs Bluetooth communication (communication according to the Bluetooth communication standard) as the short-range wireless communication unit 110, that is, what is called a Bluetooth terminal. The DUT 100 is capable of performing Bluetooth communication between other Bluetooth-equipped devices and the Bluetooth communication unit.

[0039] In TDMA terminal measurement device 1 according to this embodiment, measurement instrument 10 measures the transmission and reception characteristics of DUT 100 by performing communication operations simulating DUT 100 housed in electromagnetic shielding box 50 and another Bluetooth-enabled device.

[0040] 2, the measuring device 10 is configured to include a measuring section 20, a display section 30, and an operation section 40. The measuring section 20 includes a Bluetooth signal transmitting section 21, a receiving section 22, an analysis processing section 25, a divider 26, a memory section 27, and a test control section 28, and is configured to measure the output level and receiving sensitivity of the transmitted radio wave, etc., of the DUT 100 in accordance with the Bluetooth communication standard.

[0041] The Bluetooth signal transmitting section 21 outputs a test signal (Bluetooth signal) to the DUT 100 housed in the electromagnetic shielding box 50 via, for example, the divider 26, the coaxial cable 25a, and the test antenna 54.

[0042] The receiving unit 22 has a Bluetooth signal measuring unit 23 and an interference signal detecting unit 24. The Bluetooth signal measuring unit 23 is a functional unit that measures a Bluetooth signal received by the test antenna 54 and input via the divider 26 during execution of a transmission performance test or a reception performance test of the DUT 100 under the control of a test execution control unit 28a, which will be described later.

[0043] The interference signal detection unit 24 is a functional unit that detects interference signals exceeding a predetermined threshold output level in a frequency band (in-band frequency band) within a preset frequency band to be measured, among signals received by the test antenna 54 and input via the divider 26 while the test execution control unit 28a is executing a transmission performance test or a reception performance test of the DUT 100.

[0044] Specifically, the interference signal detection unit 24 detects the above-mentioned interference signal by targeting a baseband signal (demodulated signal) generated by the receiving process of a transmission signal from DUT100 during a transmission performance test of DUT100, or by the receiving process of a signal received from the surroundings when a receiving test signal is transmitted to DUT100 during a receiving performance test of DUT100.

[0045] An example of the interference signal detection unit 24 in this embodiment is shown in Fig. 3. As shown in Fig. 3, the interference signal detection unit 24 has an ideal signal generation unit 24a, a subtractor 24b, and an interference signal acquisition unit 24c. To the input terminal Tin of the interference signal detection unit 24, as a detection target signal, for example, during a transmission performance test of the DUT 100, a transmission signal transmitted from the DUT 100 is received by the test antenna 54, and the received signal is signal-processed via the divider 26 to obtain a demodulated signal (see Fig. 8(b) and Fig. 14(b)), or during a reception performance test of the DUT 100, a signal (unwanted signal) received from the periphery at the timing of transmitting a reception test signal to the DUT 100 is received by the test antenna 54, and the received signal is signal-processed via the divider 26 to obtain a demodulated signal. The above-mentioned demodulated signal input from the input terminal Tin is branched into two paths, and is input to the ideal signal generation unit 24a and the subtractor 24b, respectively.

[0046] Based on one of the split demodulated signals, the ideal signal generator 24a generates an ideal signal that corresponds to the demodulated signal when no interference is present.

[0047] The subtractor 24b subtracts the ideal signal generated by the ideal signal generator 24a from the demodulated signal input directly from the input terminal Tin without passing through the ideal signal generator 24a, and outputs a signal corresponding to the result of the subtraction.

[0048] The interference signal capture unit 24c performs processing to capture the signal output from the subtractor 24b, i.e., the signal resulting from subtraction of the demodulated signal input without passing through the ideal signal generation unit 24a and the ideal signal generated by the ideal signal generation unit 24a (a signal having an output level exceeding a predetermined threshold) as an interference signal.

[0049] When an interference signal is captured by the interference signal capturing unit 24c, the interference signal detection unit 24 outputs a detection result indicating that an interference signal has been detected. The interference signal detection unit 24 may be configured to detect interference signals outside the frequency band to be measured (in other words, it is sufficient if it can detect interference signals including within the frequency band to be measured). The interference signal detection unit 24 may also be configured integrally with the above-mentioned Bluetooth signal measurement unit 23. The interference signal detection unit 24, or a configuration in which the interference signal detection unit 24 and the Bluetooth signal measurement unit 23 are integrated, constitutes the interference signal detection means of the present invention.

[0050] The analysis processing unit 25 is a functional unit that analyzes the Bluetooth signal measured by the Bluetooth signal measuring unit 23. Specific examples of the analysis processing performed by the analysis processing unit 25 include measurements of the transmission power level, frequency offset, frequency drift, and modulation characteristics. The measurement results of these items (particularly, the transmission power level (output level of the transmitted radio wave), reception sensitivity (error rate relative to a specified signal level), etc.) are stored in, for example, the memory unit 27 as measurement results of the transmission characteristics and reception characteristics of the DUT 100, and can be displayed on the display unit 30 in response to a display command operation performed by the user on the operation unit 40.

[0051] The divider 26 is a wideband directional coupler that passes the output frequency of the signal output from the Bluetooth signal transmitting unit 21. As shown in FIG. 2, the divider 26 is connected to a box 55 provided in the electromagnetic shielding box 50 by a coaxial cable 25a, and is also connected to a test antenna 54. The divider 26 can input, for example, a Bluetooth signal output from the Bluetooth signal transmitting unit 21 to the short-range wireless communication unit 110 of the DUT 100 via the test antenna 54, and can input a Bluetooth signal that is transmitted from the short-range wireless communication unit 110 in response to reception of the Bluetooth signal and received by the test antenna 54 to the Bluetooth signal measuring unit 23. The divider 26 has a function of distributing a mixture of multiple inputs, and may be a device that functions as both a combiner and a divider.

[0052] The test control unit 28 is configured, for example, by a microcomputer or a personal computer including a CPU, ROM, RAM, HDD, etc. that constitute the memory unit 27, and controls the operation of each of the above-mentioned units that constitute the measurement unit 20.

[0053] The Bluetooth signal transmitting unit 21, the receiving unit 22, and the analysis processing unit 25 can be configured by digital circuits such as FPGA or ASIC, or can be configured by software by executing a predetermined program stored in advance in the storage unit 27 by the test control unit 28. Alternatively, the Bluetooth signal transmitting unit 21, the receiving unit 22, and the analysis processing unit 25 can be configured by appropriately combining hardware processing by digital circuits and software processing by a predetermined program. The test control unit 28 can also receive a new program or a program with a changed version from the outside and add or update the program to the storage unit 27.

[0054] In the test control unit 28, the functional units related to interference warning control during measurement of the transmission and reception characteristics of the DUT 100 are configured, for example, as shown in FIG. 4, to include a test execution control unit 28a, an interference warning unit 28b, a spectrogram generation unit 28c, and a display control unit 28d.

[0055] As described below, the test execution control unit 28a executes a transmission performance test for measuring the transmission characteristics of the DUT 100, and a reception performance test for measuring the reception characteristics. Specifically, the test execution control unit 28a executes a transmission performance test and a reception performance test by treating the Bluetooth terminal as the DUT 100 and communicating (short-range wireless communication) with the DUT 100 according to the Bluetooth communication standard in accordance with a predetermined test procedure (performance test scenario). The test execution control unit 28a constitutes the test execution control means of the present invention. (Transmission performance test of DUT100) A test in which measuring instrument 10 sends a transmission command of a desired signal pattern (transmission signal) to DUT 100, and DUT 100, which has received this transmission command, sends a response signal pattern which is received by measuring instrument 10, thereby measuring the transmission characteristics of DUT 100. One example of a transmission performance test is a test in which the output level of the response transmission signal sent by DUT 100 is measured. (DUT100 reception performance test) A test in which a receive command is sent from measuring instrument 10 to DUT 100, and DUT 100 measures the reception characteristics of DUT 100 based on notification indicating the reception status of the reception test signal output from measuring instrument 10 in response to the receive command. One example of a reception performance test is a test to measure the error rate of DUT 100 for the reception test signal output from measuring instrument 10.

[0056] The interference warning unit 28b is a functional unit that monitors the measurement result of the interference signal by the interference signal detection unit 24 targeting the reception signal at the test antenna 54 input via the divider 26 during the transmission performance test or reception performance test of the DUT 100 described above, as shown in Fig. 4, and issues a warning that an interference signal has been detected when the interference signal detection unit 24 detects an interference signal exceeding a predetermined threshold output level in a frequency band within a frequency band to be measured that has been set in advance by the interference signal detection unit 24. Specifically, the interference warning unit 28b is configured to display, as the warning, an interference warning message 32 (see Fig. 9) indicating that an interference signal has been detected and the reliability of the measurement result has decreased, in addition to the measurement results of the transmission measurement and the reception characteristics of the DUT 100 obtained by analyzing the measurement results of the Bluetooth signal by the Bluetooth signal measurement unit 23 by the analysis processing unit 25. The interference warning unit 28b constitutes an interference warning means of the present invention.

[0057] The spectrogram generating unit 28c is a functional unit that analyzes the measurement results of the Bluetooth signal by the Bluetooth signal measuring unit 23 and the detection results of the interference signal by the interference signal detecting unit 24 (see FIG. 4), and generates spectrogram image data for displaying a spectrogram 35a (see FIG. 10) that shows the distribution of the Bluetooth signal and the interference signal in terms of the relationship between frequency and signal strength and time, based on the analysis results. The measurement results of the transmission characteristics of the DUT 100 and the detection results of the interference signal may be configured to be analyzed by the analysis processing unit 25. The spectrogram image data generated by the spectrogram generating unit 28c is, for example, image data for displaying a graph in which the horizontal axis represents frequency and the vertical axis represents time, and the signal strength is represented by color or shade, as shown in FIG. 10. Here, the measurement results of the Bluetooth signal by the Bluetooth signal measurement unit 23 and the detection results of the interference signal by the interference signal detection unit 24 may be stored (stored) in a predetermined storage area of ​​the storage unit 27, for example, and the spectrogram generation unit 28c may read and analyze the measurement results of the Bluetooth signal and the detection results of the interference information, and generate spectrogram image data based on the analysis results. The spectrogram generation unit 28c constitutes the spectrogram generation means of the present invention.

[0058] The display control unit 28d is a functional unit that displays information related to the measurement of the transmission characteristics and reception characteristics of the DUT 100 and the interference warning control on the display unit 30. As an example, the display control unit 28d displays the measurement results of the transmission characteristics and reception characteristics of the DUT 100, for example, using a measurement result screen 31 (see FIG. 9). The measurement result screen 31 in FIG. 9 particularly illustrates a display form of the measurement results of the transmission characteristics (output level of the transmission radio wave) of the DUT 100. In addition, when the display control unit 28d recognizes that an interference signal has been measured by the interference warning unit 28b and determines that an interference warning is necessary, for example, as information related to the interference warning control, the display control unit 28d generates an interference warning message 32 by controlling the interference warning unit 28b and displays the interference warning message 32 on the measurement result screen 31 together with the measurement result. Furthermore, when the interference warning message 32 is displayed on the measurement result screen 31 together with the measurement result, the display control unit 28d performs control to switch to the measurement result screen 31 to which the interference warning message 32 has been added, for example, by accepting input of a predetermined interference warning switch display command from the operation unit 40, and to display a spectrogram 35a (see FIG. 10) based on the spectrogram image data generated by the spectrogram generation unit 28c. The display control unit 28d constitutes the display control means of the present invention.

[0059] In the configuration of measuring instrument 10 shown in FIG. 2, display unit 30 is composed of a display device such as an LCD or CRT, and is configured to display the measurement results and operation objects such as soft keys, pull-down menus, text boxes, etc. for setting measurement conditions, based on a control signal from test control unit 28.

[0060] The operation unit 40 allows the user to input operations, and is configured, for example, as a touch panel provided on the surface of the display screen of the display unit 30. Alternatively, the operation unit 40 may be configured to include an input device such as a keyboard or a mouse. The operation unit 40 may also be configured as an external control device that performs remote control using remote commands, etc. Input operations by the operation unit 40 are detected by the test control unit 28.

[0061] The user can use the operation unit 40 to select the Bluetooth communication standard that the DUT 100 supports from among multiple communication standards. In accordance with this, the user can set the measurement target frequency band using the operation unit 40. At this time, the user can set the frequency bands corresponding to the multiple frequency channels that are hopping targets and are allocated to the 2.4 GHz band defined by the Bluetooth communication standard as the measurement target frequency bands. As a result, the above-mentioned interference signal detection unit 24 measures the interference signal within the frequency band corresponding to one frequency channel that is set from among the above-mentioned multiple frequency channels.

[0062] Furthermore, the user can use the operation unit 40 to set the test type to a transmission performance test or a reception performance test, and can also input a command to switch between the measurement result screen 31 with the interference warning message 32 added thereto and the spectrogram display screen 35 (see FIG. 10). In this way, the operation unit 40 constitutes the setting means of the present invention.

[0063] Next, an interference warning control operation when the TDMA terminal measurement device 1 according to this embodiment measures the DUT 100 will be described with reference to the flowcharts of Fig. 5 and Fig. 6. Fig. 5 shows the interference warning control operation when measuring the transmission characteristics (e.g., the output level of the transmitted radio wave) of the DUT 100, and Fig. 6 shows the interference warning control operation when measuring the reception characteristics (e.g., the reception sensitivity) of the DUT 100.

[0064] The DUT 100, which is the subject of measurement of transmission characteristics and reception characteristics, is a Bluetooth terminal having a Bluetooth communication unit as the short-range wireless communication unit 110 as described above. Communication standards (wireless standards) used by Bluetooth terminals include Bluetooth Basic Rate / Enhanced Data Rate (BR / EDR) and Bluetooth Low Energy (LE). Of these Bluetooth communication standards, Bluetooth BR / EDR divides the 2.4 GHz band into 79 frequency channels (40 in LE), and performs frequency hopping (up to 1600 changes per second) to randomly change the frequency used, while performing wireless communication at up to 3 Mbps with Bluetooth-equipped devices within a short distance (for example, a radius of about 10 to 100 m).

[0065] When measuring the transmission characteristics and reception characteristics of the DUT 100, first, the test antenna 54 and the DUT 100 are set inside the electromagnetic shielding box 50 (step S1). At this time, the test antenna 54 is attached using an appropriate antenna mounting base (not shown), and the DUT 100 is placed on the upper surface of the DUT holding part 53 so that the surface on which the short-range wireless communication part 110 is formed faces the attached test antenna 54 (see FIG. 1).

[0066] Furthermore, the DUT 100 is USB-connected to the USB cable 25b extending from the box 55, and then the lid 52 is closed on the housing body 51. In this way, the DUT 100 and the test antenna 54 are enclosed in the electromagnetic shielding box 50 so as to be able to block the intrusion of electromagnetic waves from the outside into the internal space of the housing body 51, and the DUT 100 is ready for testing. The measuring instrument 10 and the electromagnetic shielding box 50 are connected in advance via the box 55 by the coaxial cable 25a. The measuring instrument 10 and the electromagnetic shielding box 50 are connected in advance via the box 55. In this case, the box 55 connects the measuring instrument 10 and the electromagnetic shielding box 50 by, for example, the coaxial cable 25a, and also connects the coaxial cable 25a and the DUT 100 in the electromagnetic shielding box 50 so that the test execution control unit 28 can issue transmission commands, reception commands, and the like via the corresponding test signals and the test antenna 54. As another example, box 55 may connect measuring instrument 10 and electromagnetic shielding box 50, for example, via coaxial cable 25a, and may also be USB-connected, for example, via USB cable 25b, so that transmission commands, reception commands, etc. from test execution control unit 28 can be sent to DUT 100 in electromagnetic shielding box 50 via a control line separate from coaxial cable 25a.

[0067] After the test preparation is completed, the test conditions are accepted by the user (step S2). Here, the test execution control unit 28a accepts settings such as the communication standard of the DUT 100, the measurement frequency band, and the test type, for example, by the user's operation on the operation unit 40. The communication standard accepted at this time is, for example, either Bluetooth BR / ED or Bluetooth LE, and the measurement frequency band is a frequency band corresponding to a desired frequency channel out of 70 channels or 40 channels specified in each communication standard. In addition, the test type accepted is, for example, a transmission performance test, a reception performance test, or both. The processing of step S2 can be performed in the reverse order to the processing of step S1 described above.

[0068] Next, the test execution control unit 28a judges whether the test type set in step S2 is a transmission performance test or a reception performance test (step S3). If the test type set is a transmission performance test ("transmission performance test" in step S3), the process proceeds to step S4 to perform a transmission performance test on the DUT 100.

[0069] 5, the transmission performance test of the DUT 100 is carried out in steps S4 to S6. In the transmission performance test of the DUT 100, the test execution control unit 28a transmits a transmission command for a desired signal pattern in the measurement target frequency band set in step S2 to the DUT 100 (step S4), and the DUT 100, which receives the transmission command, transmits a response signal of the signal pattern (Bluetooth signal) in the measurement target frequency band at the test antenna 54, which is branched by the divider 26 and input to the Bluetooth signal measurement unit 23, and the Bluetooth signal measurement unit 23 measures the received signal (step S5). Furthermore, the analysis processing unit 25 analyzes the Bluetooth signal measured by the Bluetooth signal measurement unit 23, and stores the analysis result as a measurement result of the transmission characteristic of the DUT 100. Data of the measurement result of the transmission characteristic of the DUT 100 is stored, for example, in a predetermined transmission characteristic measurement result storage area in the memory unit 27.

[0070] In accordance with the transmission performance test of the DUT 100 in the above steps S4 to S6, the test execution control unit 28a transmits an interference signal detection command to the interference signal detection unit 24. Based on this detection command, the interference signal detection unit 24 performs an interference signal detection process for a frequency band (in-band frequency band) within the measurement target frequency band set in the above step S2 (step S7). The main interference signal to be detected here is an incoming signal from the outside that may interfere with the test result (measurement result of transmission characteristics) of the transmission performance test of the DUT 100 in the above steps S4 to S6. The interference signal may include, for example, a spurious signal near the measurement target frequency band that is output by the DUT 100 during the transmission performance test. Data on the detection result of the interference signal in step S7 is stored, for example, in a predetermined interference signal detection result storage area in the storage unit 27.

[0071] The operation of the interference signal detection process in step S7, which is targeted within the frequency band to be measured, will be described with reference to Fig. 7 and Fig. 8. In the interference signal detection process, as shown in the flow chart of Fig. 7, the interference signal detection unit 24 inputs the received signal, which is received by the test antenna 54 in the transmission performance test of the DUT 100 described above and has been signal-processed, as the signal to be detected (hereinafter, real signal) S1 from the input terminal Tin (step S30). The real signal S1 is, for example, a demodulated signal having an on interval and an off interval as shown in Fig. 8(b). In this example, the real signal S1 is one in which the interference signal Sitf (see Fig. 8(c)) is superimposed on the first on interval in the figure (see the dotted ellipse).

[0072] In the interference signal detection unit 24, the real signal S1 input from the input terminal Tin is branched into two paths, one of which is input to the subtractor 24b and the other to the ideal signal generation unit 24a. The ideal signal generation unit 24a generates a demodulated signal having an ideal waveform when no interference is present, that is, an ideal signal, based on the input real signal S1 (step S31), and outputs the ideal signal to the subtractor 24b. The ideal signal Si is, for example, a perfect square wave with no interference signal Sitf (see FIG. 8(c)) superimposed thereon, as shown in FIG. 8(a).

[0073] Next, the subtractor 24b receives the real signal S1 sent directly through the ideal signal generator 24a and the ideal signal generated by the ideal signal generator 24a, and performs signal processing to subtract (cancel) the ideal signal from the real signal S1 (step S32). The signal Sitf, which is the real signal S1 with the ideal signal Si component cancelled, is output to the interference signal capture unit 24c.

[0074] The interference signal capture unit 24c captures the signal Sitf input from the subtractor 24b and detects the interference signal based on the signal Sitf (step S33). Here, the signal Sitf corresponds to the interference signal superimposed on the leading ON section of the real signal S1 as shown in FIG. 8(c).

[0075] Although FIG. 8 illustrates a case where an interference signal is detected during an ON interval of the real signal S1, the interference signal detector 24D can also detect an interference signal during an OFF interval of the real signal S1 in the same manner.

[0076] Returning to Fig. 5 again, the interference warning process operation will be described. When the transmission performance test of the DUT 100 in the above steps S4 to S6 and the detection process of the interference signal in the above step S7 are completed, the interference warning unit 28b then checks whether or not there is an interference signal having an output level exceeding a preset threshold among the interference signals detected in step S7 (step S8). If it is determined that there is no interference signal having an output level exceeding the threshold (NO in step S8), the display control unit 28d reads data of the measurement result of the transmission characteristics of the DUT 100 from the transmission characteristics measurement result storage area of ​​the memory unit 27, and displays the measurement result of the transmission characteristics of the DUT 100 on the display unit 30 based on the data (step S9). The measurement result of the transmission characteristics displayed here has, for example, a display content obtained by deleting the interference warning message 32 from the measurement result screen 31 shown in Fig. 9.

[0077] On the other hand, if it is determined that an interference signal having an output level exceeding the threshold value is present (YES in step S8), the interference warning unit 28b instructs the display control unit 28d to display a screen for interference warning, and in response to this instruction, the display control unit 28d displays, on the display unit 30 (step S10), a measurement result screen 31 for interference warning (see FIG. 9) including, for example, the measurement result of the transmission characteristics of the DUT 100 displayed in step S9 and an interference warning message 32 that warns that an interference signal has been detected during a transmission performance test of the DUT 100 (see steps S4 to S6). Here, the measurement result displayed in the main area 31a of the measurement result screen 31 is the measurement result of the transmission characteristics of the DUT 100.

[0078] When the measurement result screen 31 for interference warning is displayed, for example, if the above-mentioned switching command is input by user operation on the operation unit 40, the interference warning unit 28b instructs the display control unit 28d to display a spectrogram, and in response to this instruction, the display control unit 28d reads (or generates) image data of a spectrogram display screen 35 having a spectrogram 35a (see Figure 10) from a specified storage area, and based on the image data, switches the spectrogram display screen 35 to the measurement result screen 31 that had been displayed until then and displays it on the display unit 30 (step S11).

[0079] Image data (spectrogram image data) of the spectrogram 35a to be displayed on the spectrogram display screen 35 is generated in advance by the spectrogram generating unit 28c based on data of the measurement results of the transmission characteristics of the DUT 100 stored in the transmission characteristics measurement result storage area of ​​the memory unit 27 and data of the detection results of the interference signal stored in the interference signal detection result storage area, and is stored, for example, in a predetermined storage area of ​​the memory unit 27. In step S11, the display control unit 28d reads out the spectrogram image data from the memory unit 27 and displays the spectrogram 35a using the spectrogram display screen 35 based on the spectrogram image data. The timing at which the spectrogram generating unit 28c generates the spectrum image data is not particularly limited, and may be, for example, either when it is determined in step S8 that an interference signal having an output level exceeding the threshold exists, or when the input of the switching command is received in step S11.

[0080] However, the spectrogram 35a shown in Fig. 10 corresponds to the interference signal detection result for a frequency band outside the measurement target frequency band. That is, Fig. 10 merely illustrates the display form of the spectrogram 35a for convenience, and when switching the display in step S11, a spectrogram image based on the interference signal detection result in a preset measurement target frequency range (frequency band near the focus point Pa) is displayed from the spectrogram 35a shown in Fig. 10. An example of this spectrogram image is shown in Fig. 11.

[0081] The series of interference warning control operations related to the measurement of the transmission characteristics of DUT100 shown in Figure 5 can be terminated by a user operation to close the screen showing the measurement results of the transmission performance test displayed in step S9, or the measurement result screen 31 (see Figure 9) including the interference warning message 32 displayed in step S10, or the spectrogram display screen 35 displayed in step S11.

[0082] On the other hand, if it is determined in step S3 above that the test type is a reception performance test ("reception performance test" in step S3), the test execution control unit 28a proceeds to step S20 in FIG.

[0083] 6, the reception performance test of the DUT 100 is carried out in steps S20 to S22. In the reception performance test of the DUT 100, the test execution control unit 28a transmits, for example, a reception test signal having a desired signal pattern in the measurement target frequency band set in step S2 to the DUT 100 from the test antenna 54, and a reception command for the reception test signal, for example, remotely (step S20). Subsequently, the test execution control unit 28a receives a notification (reception status notification) that the DUT 100 transmits to the measuring instrument 10 via the short-range wireless communication unit 110 in response to the reception command, of the reception status of the reception test signal (step S21). Here, the DUT 100 transmits (notifies) the number of received packets, the number of error packets, etc., as the reception status.

[0084] From this reception status notification (step S21), the error rate result (whether the error rate is below a specified value or not) is obtained, and the measurement result data is stored as the measurement result of the reception characteristics of the DUT 100, for example, in a predetermined reception characteristics measurement result storage area in the memory unit 27 (step S22).

[0085] In accordance with the reception performance test of the DUT 100 in the above steps S20 to S22, the test execution control unit 28a transmits an interference signal detection command to the interference signal detection unit 24. Based on this detection command, the interference signal detection unit 24 performs an interference signal detection process for the frequency range within the frequency band of the measurement target frequency band set in the above step S2 (step S23). The main interference signal to be detected here is an incoming signal from outside that may interfere with the test result (reception specific measurement result) of the reception performance test of the DUT 100 in the above steps S20 to S22. The interference signal may include, for example, a spurious signal near the measurement target frequency band that is output by the DUT 100 during the reception performance test. Data on the measurement result of the interference signal in step S23 is stored, for example, in a predetermined interference signal detection result storage area in the memory unit 27.

[0086] The process of detecting an interference signal within the measurement target frequency band in step S23 is also basically performed according to the flowchart shown in Fig. 7. However, in the process of detecting an interference signal in step S23, while a reception test signal is being transmitted to the DUT 100 in the reception performance test of the DUT 100 described above, a demodulated signal that is received by the test antenna 54 from the surroundings and subjected to signal processing is input as a real signal S1 from the input terminal Tin. Thereafter, the interference signal detection unit 24 performs a process of canceling the ideal signal Si from the real signal S1, as in step S7, and performs a capture (detection) process on the signal after the cancellation of the ideal signal Si as an interference signal.

[0087] When the reception performance test of the DUT 100 in the above steps S20 to S22 and the detection process of the interference signal in the above step S23 are completed, the interference warning unit 28b then checks whether or not there is an interference signal having a signal level exceeding a preset threshold among the interference signals detected in step S23 (step S24). If it is determined that there is no interference signal having a signal level exceeding the threshold (NO in step S24), the display control unit 28d reads out data of the measurement result of the reception characteristics of the DUT 100 from the reception characteristics measurement result storage area of ​​the memory unit 27, and displays the measurement result of the reception characteristics of the DUT 100 on the display unit 30 based on the data (step S25). The measurement result of the reception characteristics displayed here is, for example, one that does not have the interference warning message 32 displayed on the measurement result screen 31 shown in FIG.

[0088] On the other hand, if it is determined that an interference signal having a signal level exceeding the threshold exists (YES in step S24), the interference warning unit 28b instructs the display control unit 28d to display a screen for interference warning, and in response to this instruction, the display control unit 28d displays on the display unit 30 (step S26) a measurement result screen 31 for interference warning, which includes, for example, the measurement result of the reception characteristics of the DUT 100 displayed in step S25 and an interference warning message 32 (see FIG. 9) that warns that an interference signal has occurred during a reception performance test of the DUT 100 (see steps S20 to S23). However, the measurement result displayed in the main area 31a of the measurement result screen 31 here is not the transmission characteristics measurement result displayed in the main area 31a of the measurement result screen 31 shown in FIG. 9, but is replaced with the measurement result of the reception characteristics of the DUT 100 described above.

[0089] When the measurement result screen 31 for interference warning is displayed, for example, if the above-mentioned switching command is input by user operation on the operation unit 40, the interference warning unit 28b instructs the display control unit 28d to display a spectrogram, and in response to this instruction, the display control unit 28d reads (or generates) image data of the spectrogram display screen 35 having the spectrogram 35a (see Figure 10) from a specified storage area, and based on the image data, switches the spectrogram display screen 35 to the measurement result screen 31 that had been displayed until then and displays it on the display unit 30 (step S27).

[0090] Image data (spectrogram image data) of the spectrogram 35a to be displayed on the spectrogram display screen 35 is generated in advance by the spectrogram generating unit 28c based on data of the measurement result of the reception characteristics of the DUT 100 stored in the reception characteristics measurement result storage area of ​​the storage unit 27 and data of the detection result of the interference signal stored in the interference signal detection result storage area, and is stored, for example, in a predetermined storage area of ​​the storage unit 27. In step S27, the display control unit 28d reads out the spectrogram image data from the storage unit 27 and displays the spectrogram 35a using the spectrogram display screen 35 based on the spectrogram image data. The timing at which the spectrogram generating unit 28c generates the spectrum image data is not particularly limited, and may be, for example, either when it is determined in step S24 that an interference signal having an output level exceeding the threshold exists, or when the input of the switching command is received in step S27.

[0091] The series of interference warning control operations related to the measurement of the reception characteristics of DUT100 shown in FIG. 6 can be terminated by a user operation to close the screen showing the measurement results of the reception characteristics displayed in step S25, or the measurement results screen 31 of the reception characteristics including the interference warning message 32 displayed in step S26, or the spectrogram display screen 35 displayed in step S27.

[0092] The display form of the measurement result screen 31 for warning interference, which is displayed in step S10 in Fig. 5 and step S26 in Fig. 6 during the measurement operation of the transmission characteristics and reception characteristics of the DUT 100 shown in Fig. 5 and Fig. 6, will be described in detail. Fig. 9 shows an example of a display of an interference warning message 32 on the measurement result screen 31 for warning interference when an interference signal is detected in a transmission performance test or reception performance test of the DUT 100. The measurement result screen 31 shown in Fig. 9 shows an example of a display when an interference signal is detected in a transmission performance test of the DUT 100, and the measurement results of the transmission characteristics of the DUT 100 are displayed in the main area 31a. In particular, in Fig. 9, each item showing the measurement results of the output level of the transmission radio wave of the DUT 100 is displayed in a vertical array of multiple columns.

[0093] In the measurement result screen 31 for interference warning shown in FIG. 9 (the same is true for the measurement result screen 31 for reception characteristics for interference warning, not shown), an interference warning notification area is provided, for example, in the upper area of ​​the area displaying the measurement results of each of the above items, and an interference warning message 32 stating "An interference signal has been detected" is displayed in the interference warning notification area.

[0094] According to the measurement result screen 31, which is composed of the measurement result of the transmission characteristics of the DUT 100 (or the measurement result of the reception characteristics of the DUT 100) and an interference warning message 32 stating "Interference signal detected," the user can recognize that the displayed measurement result may be subject to interference from the surroundings. This makes it easier for the user to question the accuracy of the displayed measurement result, and improves the accuracy of the measurement result, compared to the conventional display format in which the possibility of interference from the surroundings could not be known at all.

[0095] In addition, the interference warning message 32 need only contain content that can inform the user that there is a possibility of interference from the surroundings, and it goes without saying that the message content can be various and is not limited to "Interference signal detected."

[0096] For example, if the result of the interference signal detection process indicates that interference is occurring due to a Bluetooth hopping pattern, a wireless LAN (Wi-Fi) spectrum pattern, a signal emitted by a device such as a microwave oven, or the like (see FIG. 10), a message that estimates the identified content as a cause may be displayed as interference warning message 32. In this case, it can be inferred that the influence is due to the above-mentioned factors around the electromagnetic shielding box 50, and appropriate measures can be taken.

[0097] In addition, FIG. 9 shows an example of the interference warning message 32 being displayed in black text in a white area, but the display form is not limited to this, and various display forms can be selected, such as displaying the interference warning message 32 in various colors, lighting up, or flashing.

[0098] Next, a detailed description will be given of the display form of the spectrogram display screen 35 displayed in step S11 of Fig. 5 and step S27 of Fig. 6 during measurement of the transmission characteristics and reception characteristics of the DUT 100 shown in Fig. 5 and Fig. 6. One display form of the spectrogram 35a generated based on the measurement results of the interference signal in the reception performance test of the DUT 100 (however, the content corresponds to the interference signal detection result for a frequency band outside the frequency band to be measured) is shown in Fig. 10. The spectrogram generation unit 28c is capable of generating the spectrogram 35a based on the measurement results of the interference signal in the transmission performance test of the DUT 100.

[0099] As shown in Fig. 10, the spectrogram 35a displayed on the spectrogram display screen 35 has frequency on the horizontal axis and time on the vertical axis, and is a graph showing the relationship between frequency and signal strength and time of the distribution of the interference signal obtained by analyzing the measurement result of the interference signal in step S23 of Fig. 5 (however, the measurement result of the interference signal when the frequency band outside the measurement target frequency band is targeted). Specifically, the spectrogram 35a in this example is a graph showing the relationship between frequency and signal strength and time of the distribution of the interference signal in the time interval from 0 to 5.79 seconds of a Bluetooth signal that is the measurement target for the frequency range from 2.4 GHz to 2.5 GHz.

[0100] According to this spectrogram 35a, when the frequency direction (horizontal direction) is considered as the width and the time direction (vertical direction) is considered as the height, each interference signal is represented by a rectangular shape of constant height and having a width corresponding to each frequency width, and the strength of the interference signal is represented by the shade of the color of the rectangular shape.

[0101] This allows the user to recognize that measurements of Bluetooth signals in a frequency band near the point of interest Pa are being performed at regular time intervals, for example, from a small-width image 36 that appears to extend continuously in the time direction in the frequency band near the point of interest Pa in the spectrogram 35a shown in Fig. 10. Here, the width of the image corresponds to, for example, the frequency bandwidth of one frequency channel in the Bluetooth communication standard. For this reason, images at other positions having a width equivalent to that of the image above can be considered to be other Bluetooth signals in a frequency band other than the measurement target frequency band.

[0102] On the other hand, images at each position outside the measurement target frequency band having a width larger than the width of the above image are presumed to be interference signals other than Bluetooth signals. For these images at each position outside the measurement target frequency band, it can be presumed from the size of their width that, for example, image 37 having a predetermined width is a wireless LAN (Wi-Fi) signal, and image 38 having a width larger than that is a signal of another short-range wireless communication standard. Furthermore, for example, image group 39 having a large width and overlapping multiple mixed signals in the time direction can be presumed to be interference signals generated by, for example, a microwave oven or the like.

[0103] Fig. 11 shows an example of a spectrogram 35a based on the interference signal detection result within a preset measurement target frequency range among the spectrograms 35a shown in Fig. 10. In Fig. 11, the frequency band near the focus point Pa in Fig. 10 is shown as the "measurement frequency range", and an image 36 extending continuously in the time direction near the focus point Pa in Fig. 10 is shown as the "measurement target". From the image in Fig. 10, it can be recognized that when measuring the DUT 100 (measurement of transmission characteristics or reception characteristics) while performing communication while performing frequency hopping that randomly changes the frequency channel within the "measurement frequency range" for a Bluetooth terminal as the DUT 100, each frequency channel (79 for Bluetooth BR / EDR, 40 for LE) as the "measurement target" is measured at a predetermined hopping period, and interference signals Is1 and Is2 are also detected for the frequency band within the band of the "measurement frequency range".

[0104] Here, it can be seen that the interference signal Is1 is a Bluetooth signal in a frequency band within the "measurement frequency range" transmitted from another Bluetooth terminal, and the interference signal Is2 is a Bluetooth signal in a frequency band within the "measurement frequency range" transmitted from the other Bluetooth terminal described above or from yet another Bluetooth terminal. Here, it can be inferred that the interference signal Is1 is, for example, an interference signal in the off interval of the real signal S1 shown in Fig. 8(b), and the interference signal Is2 is similarly an interference signal in the on interval of the real signal S1.

[0105] As described above, in the TDMA terminal measuring device 1 according to the present embodiment, for example, as shown in FIG. 9, after the interference warning measurement result screen 31 with the interference warning message 32 added thereto is displayed, the display screen 35 can be switched to a spectrogram display screen 35 having a spectrogram 35a shown in FIG. 11, whereby the user can at a glance check from the spectrogram 35a which frequency channel of which Bluetooth communication standard is currently being measured and how the interference signal in the in-band frequency band of the measurement target frequency band is distributed. This allows the user to recognize the measurement result displayed on the measurement result screen 31 (see FIG. 9) before switching, taking into consideration the possibility that the measurement result is influenced by the interference signal having the distribution shown in FIG. 11. In short, a user who performs a performance test of the DUT 100 (Bluetooth terminal) using the TDMA terminal measuring device 1 according to the present embodiment can correctly judge the accuracy of the measurement result of the transmission and reception characteristics of the Bluetooth terminal under the OTA environment in light of the radio wave conditions within the measurement target frequency band. Furthermore, it is possible to quickly respond to the cause investigation when the expected measurement result is not obtained.

[0106] As described above, TDMA terminal measurement device 1 according to the first embodiment accommodates a TDMA terminal as DUT100 in electromagnetic shielding box 50 and measures the transmission characteristics and reception characteristics of DUT100 in an OTA environment, and is configured to include: operation unit 40 for setting measurement conditions including the frequency band to be measured; test execution control unit 28a for executing a transmission performance test to measure the transmission characteristics of DUT100 and a reception performance test to measure the reception characteristics of DUT100 by performing short-range wireless communication with DUT100 in accordance with a predetermined test procedure; interference signal detection unit 24 for detecting an interference signal exceeding a predetermined threshold output level for a frequency band within the frequency band to be measured set by operation unit 40 during the transmission performance test or reception performance test; and interference warning unit 28b for issuing a warning that an interference signal has been detected in association with the measurement results of the transmission characteristics or the measurement results of the reception characteristics of DUT100 when an interference signal is detected by interference signal detection unit 24.

[0107] With this configuration, the TDMA terminal measurement device 1 according to the first embodiment can recognize, for example, an interference signal within the measurement frequency band when measuring the transmission and reception characteristics (transmission characteristics and reception characteristics) of the TDMA terminal as the DUT 100 under an OTA environment, by issuing a warning. It is possible to suggest to the user that the measurement result of the transmission and reception characteristics associated with the warning may be affected by the interference signal within the band, and this allows the user to judge the accuracy of the measurement result in light of the radio wave conditions within the frequency band to be measured, and it is possible to expect an improvement in the accuracy of the measurement result. Also, even when the expected measurement result is not obtained (an uncertain measurement result is obtained), it is possible to quickly respond to the cause investigation based on the possibility of the influence of the interference signal.

[0108] Furthermore, in the TDMA terminal measurement device 1 according to the first embodiment, the test execution control unit 28a is configured to execute a transmission performance test in which a transmission command for a desired transmission signal is sent to the DUT 100, and the transmission characteristics of the DUT 100 are measured based on the measurement results of the transmission signal sent by the DUT 100 in response to the transmission command, and a reception performance test in which a reception command and a reception test signal are sent to the DUT 100, and the reception characteristics of the DUT 100 are measured based on a notification of the reception status sent by the DUT 100 upon receiving the reception test signal.

[0109] With this configuration, the TDMA terminal measuring device 1 of the first embodiment measures the transmission level, signal quality, or receiving sensitivity of the radio waves of a TDMA terminal, and when an interfering signal is detected within the frequency band to be measured during the measurement, it issues a warning to the effect that an interfering signal has been detected in association with the measurement results, thereby suggesting to the user that the measured transmission level or receiving sensitivity of the radio waves may be affected by an interfering signal, which is expected to improve the reliability of the measurement results, and also makes it possible to quickly respond to the investigation of the cause when an uncertain measurement result is obtained.

[0110] In addition, in the TDMA terminal measuring device 1 of the first embodiment, the interference signal detection unit 24 is configured to have an ideal signal generation unit 24a that inputs a demodulated signal S1 generated by reception processing of a transmission signal from DUT 100 in a transmission performance test of DUT 100 or by reception processing of a signal received from the surroundings when a reception test signal is transmitted to DUT 100 in a reception performance test of DUT 100, and generates an ideal signal Si of the demodulated signal S1 based on the demodulated signal S1, and an interference signal capture unit 24c that captures a signal Sitf obtained by subtracting the ideal signal Si from the demodulated signal S1 as an interference signal.

[0111] With this configuration, the TDMA terminal measurement device 1 according to the first embodiment can reliably detect interference signals within the frequency band to be measured, with a simple configuration having an ideal signal generating unit 24a and an interference signal capturing unit 24c.

[0112] In addition, in the TDMA terminal measuring device 1 of the first embodiment, the electromagnetic wave shielding box 50 houses a Bluetooth terminal that communicates according to the Bluetooth communication standard as a TDMA terminal, and the test execution control unit 28a treats the Bluetooth terminal as a DUT 100 and performs a transmission performance test and a reception performance test of the DUT 100 by communicating with the DUT 100 according to the Bluetooth communication standard in accordance with a test procedure.

[0113] With this configuration, the TDMA terminal measurement device 1 according to the first embodiment can be applied to measuring the transmission characteristics and reception characteristics of a Bluetooth terminal that communicates according to the Bluetooth communication standard in an OTA environment. When an interference signal is measured within the frequency band to be measured, a warning to that effect is issued, so that it is easy to determine whether the measurement results related to the transmission characteristics and reception characteristics of the Bluetooth terminal displayed together are reliable. In addition, when a warning is issued to the effect that an interference signal has been detected, even in a situation where an unreliable measurement result is obtained, it becomes easy to isolate the cause as being due to an interference signal rather than an abnormality in the Bluetooth terminal.

[0114] In addition, in the TDMA terminal measuring device 1 according to the first embodiment, the operation unit 40 sets, as the measurement target frequency bands, frequency bands corresponding to the multiple frequency channels to be hopped that are allocated to the 2.4 GHz band defined by the Bluetooth communication standard, and the interference signal detection unit 24 is configured to measure the interference signal as a frequency band within the frequency band corresponding to one frequency channel set by the operation unit 40 from among the multiple frequency channels.

[0115] With this configuration, the TDMA terminal measuring device 1 of the first embodiment can easily check the accuracy of the measurement results of the transmission characteristics and reception characteristics of a desired frequency channel among multiple frequency channels that are successively switched over in hopping-type communication by a Bluetooth terminal, making it easy to isolate the cause even if an unreliable measurement result is obtained.

[0116] In addition, in the TDMA terminal measuring device 1 according to the first embodiment, the interference warning unit 28b is configured to display, as the warning, an interference warning message 32 indicating that an interference signal has been detected and the reliability of the measurement results of the transmission characteristics or the reception characteristics of the DUT 100 has decreased, in addition to the measurement results of the transmission characteristics or the reception characteristics.

[0117] With this configuration, the TDMA terminal measurement device 1 of the first embodiment warns that an interference signal has been measured by displaying an interference warning message 32 added to the measurement result, making the user more aware that the measurement result may be affected by an interference signal, and making it possible to reliably determine the accuracy of the measurement result taking interference into account.

[0118] In addition, the TDMA terminal measuring device 1 according to the first embodiment further includes a spectrogram generating unit 28c that analyzes the detection result of the interference signal by the interference signal detection unit 24 and generates, based on the analysis result, a spectrogram 35a that represents the distribution of the interference signal in terms of the relationship between frequency and signal strength and time, and a display control unit 28d that switches to a screen that displays an interference warning message 32 and displays the spectrogram in response to a predetermined switching command.

[0119] With this configuration, the TDMA terminal measurement device 1 according to the first embodiment can more easily grasp the accuracy of the measurement result in light of the distribution of interference signals within the measurement target frequency band in the displayed spectrogram 35a. Also, by looking at the distribution of interference signals in the spectrogram 35a, it becomes easier to investigate the cause when an uncertain measurement result is obtained.

[0120] The TDMA measurement method according to the first embodiment is a TDMA measurement method that uses TDMA terminal measurement device 1 having any of the above-described configurations, houses a TDMA terminal as DUT 100 in electromagnetic shielding box 50, and measures transmission characteristics and reception characteristics of DUT 100 in an OTA environment, and includes a setting step (S2) of setting measurement conditions including a measurement target frequency band, and a transmission performance test of DUT 100 that measures the transmission characteristics and a reception performance test that measures the reception characteristics by performing short-range wireless communication with DUT 100 according to a predetermined test procedure. the test execution control step (S4 to S6, S20 to S22) for detecting an interference signal exceeding a predetermined threshold output level for a frequency band within the measurement target frequency band set in the setting step while a transmission performance test or a reception performance test of the DUT100 is being executed; and an interference warning step (S10, S26) for issuing a warning that an interference signal has been detected in association with the measurement results of the transmission characteristics or the reception characteristics of the DUT100 if an interference signal is detected in the interference signal detection step.

[0121] With this configuration, the TDMA terminal measurement method according to the first embodiment uses the TDMA terminal measurement device 1 having any of the above configurations, and when measuring the transmission and reception characteristics of the TDMA terminal as the DUT 100 under an OTA environment, for example, if an interference signal is measured within the measurement frequency band, the user can recognize this by a warning. It is possible to suggest to the user that the measurement result of the transmission and reception characteristics of the DUT 100 associated with the warning may be affected by the interference signal within the band, and this allows the user to judge the accuracy of the measurement result in light of the radio wave conditions within the frequency band to be measured, and the accuracy of the measurement result can be expected to improve. Also, even when the expected measurement result is not obtained (an uncertain measurement result is obtained), it is possible to quickly respond to the cause investigation based on the possibility of the influence of the interference signal.

[0122] Second Embodiment A TDMA terminal measurement device according to the second embodiment of the present invention (hereinafter, for convenience, it will be identified by the reference symbol 1A) is configured to include a measurement device 10A equipped with an interference signal detection unit 24D having the functional configuration shown in FIG. 12, for example, instead of the interference signal detection unit 24 (see FIG. 3) according to the first embodiment. In the TDMA terminal measurement device 1A according to the second embodiment, the configuration other than the interference signal detection unit 24D equipped in the measurement device 10A is the same as that of the TDMA terminal measurement device 1 according to the first embodiment. In the following, the points different from the interference signal detection unit 24 will be mainly described, and a detailed description of the points in common with the interference signal detection unit 24 will be omitted.

[0123] The interference signal detection unit 24D according to the second embodiment mounted on the measuring instrument 10A, like the interference signal detection unit 24 according to the first embodiment, detects an interference signal from a baseband signal (demodulated signal) generated by reception processing of a transmission signal from the DUT 100 in a transmission performance test of the DUT 100, or by reception processing of a signal received from the periphery when a reception test signal is transmitted to the DUT 100 in a reception performance test of the DUT 100. However, the interference signal detection unit 24D has a different functional configuration from the interference signal detection unit 24, and is configured by, for example, a reference signal holding unit 24e, a comparator 24f, and an interference signal acquisition unit 24g as shown in FIG.

[0124] In the interference signal detector 24D, the demodulated signal (real signal S1: see the first embodiment) input from the input terminal Tin is branched into two paths, which are input to a reference signal holder 24e and a comparator 24f, respectively.

[0125] The reference signal holding unit 24e sequentially holds one of the split demodulated signals as a reference signal S11 for a predetermined time length. The held reference signal S11 for the predetermined time length can be sequentially referred to by the comparison unit 24f.

[0126] The comparator 24f compares the demodulated signal (real signal S1) directly input from the input terminal Tin with the reference signal S11 held in the reference signal holder 24e for a predetermined timing interval, and outputs a signal corresponding to the difference between the two signals for the timing interval. The comparison targets of the comparator 24f are, for example, the on-interval of the real signal S1 and the on-interval of the reference signal S11 other than the on-interval of the real signal S1, or the off-interval of the real signal S1 and the off-interval of the reference signal S11 other than the off-interval of the real signal S11.

[0127] The interference signal capture unit 24g performs processing to capture the signal output from the comparison unit 24f, i.e., the signal Sitf (a signal having an output level exceeding a predetermined threshold) corresponding to the difference between different on-intervals or off-intervals of the real signal S1 and the reference signal S11, as an interference signal.

[0128] When the interference signal capturing unit 24g captures an interference signal (signal Sitf), the interference signal detecting unit 24D outputs a detection result indicating that an interference signal has been detected. The interference signal detecting unit 24D constitutes an interference signal detecting means of the present invention.

[0129] In the TDMA terminal measurement device 1A according to the second embodiment having the measuring device 10A equipped with the interference signal detection unit 24D configured as described above, the interference warning control operation according to the flowcharts of FIGS. 5 and 6 is also carried out.

[0130] The operation of the interference signal detection process (see step S7 in FIG. 5 and step S23 in FIG. 6) performed by the interference signal detection unit 24D of the TDMA terminal measurement device 1A according to the second embodiment, which is performed within the frequency band to be measured, will be described with reference to FIG. 13 and FIG. 14. In the interference signal detection process, the interference signal detection unit 24D inputs a signal to be detected (hereinafter, real signal) S1 from the input terminal Tin as shown in the flowchart of FIG. 13 (step S40). The real signal S1 is, for example, a demodulated signal having an on interval and an off interval as shown in FIG. 14(b). The real signal S1 in this example is a signal in which an interference signal Sitf (see FIG. 14(c)) is superimposed (see the dotted ellipse) on the second off interval.

[0131] In the interference signal detection unit 24D, the real signal S1 inputted from the input terminal Tin is branched into two paths, one of which is inputted to the comparison unit 24f, and the other is inputted to the reference signal holding unit 24e. The reference signal holding unit 24e holds the input real signal S1 as a reference signal S11 so that it can be referred to appropriately (step S41). Fig. 14(a) shows a holding form of the reference signal S11 at a timing shifted from the real signal S1, and the interference signal Sitf (see Fig. 14(c)) is not superimposed in any of the on and off intervals.

[0132] Next, the comparison unit 24f compares different on-sections or off-sections of the real signal S1 input from the input terminal Tin with the reference signal S11 held by the reference signal holding unit 24e, and outputs a signal Sitf corresponding to the difference to the interference signal acquisition unit 24g (step S42).

[0133] The interference signal capturing unit 24g captures the signal Sitf output from the comparator 24f and detects the interference signal based on the signal Sitf (step S43). Here, the signal Sitf corresponds to the interference signal superimposed on the second off interval of the real signal S1 as shown in FIG. 14(c).

[0134] Although FIG. 14 illustrates a case where an interference signal is detected during an OFF interval of the real signal S1, the interference signal detector 24D can also detect an interference signal during an ON interval of the real signal S1 in a similar manner.

[0135] In this way, the TDMA terminal measuring device 1A according to the second embodiment is provided with an interference signal detection unit 24D having: a reference signal holding unit 24e that inputs a demodulated signal S1 generated by the reception processing of a transmission signal from the DUT 100 in a transmission performance test of the DUT 100, or by the reception processing of a signal received from the surroundings when a reception test signal is transmitted to the DUT 100 in a reception performance test of the DUT 100, and holds it as a reference signal S11; and an interference signal capture unit 24g that captures a signal Sitf that is the difference between different on-intervals or off-intervals of the demodulated signal S1 and the reference signal S11 as an interference signal.

[0136] According to this configuration, it is possible to more easily and reliably detect an interference signal from the difference between each section (on section or off section) of the input demodulated signal S1 and a section (a section where an interference signal is not superimposed) of the reference signal S11 other than each section. Also, according to the configuration including the interference signal detector 24D, as with the TDMA terminal measuring device 1 according to the first embodiment including the measuring device 10 equipped with the interference signal detector 24, it is possible to correctly determine the reliability of the measurement result of the transmission and reception characteristics of the Bluetooth terminal in the OTA environment in light of the radio wave conditions within the frequency band to be measured, and it is also possible to quickly respond to the cause investigation when the expected measurement result is not obtained.

[0137] According to the above embodiments (first and second embodiments), the setting means realized by the operation unit 40 is exemplified as being configured to set, as the measurement target frequency band, frequency bands corresponding to a plurality of frequency channels to be hopped defined by the Bluetooth communication standard, respectively. However, the setting means is not limited to this, and may be configured to directly set, for example, any frequency range (a frequency band corresponding to the above-mentioned band).

[0138] In addition, in the above embodiment, an example is given in which some of the communication during performance testing (transmission performance testing and reception performance testing) between the Bluetooth terminal contained as DUT 100 in the electromagnetic shielding box 50 and the measuring instrument 10 is performed via wired communication, but all of the communication may be performed via wireless communication.

[0139] Furthermore, the present invention can be practiced in ways other than those described above, and it goes without saying that various modifications and applications of the interference warning control function in particular can be applied. [Industrial Applicability]

[0140] As described above, the TDMA measurement device and TDMA measurement method of the present invention have the effect of being able to correctly judge the reliability of the measurement results of the transmission and reception characteristics of a TDMA terminal in an OTA environment in light of the radio wave conditions within the frequency band to be measured, and are also able to quickly respond to investigation into the cause when the expected measurement results are not obtained. These effects are useful for TDMA measurement devices and TDMA measurement methods in general that measure the transmission and reception characteristics of TDMA terminals such as Bluetooth terminals. [Explanation of symbols]

[0141] 1. 1A TDMA terminal measuring device 24, 24D Interference signal detection unit (interference signal detection means) 24a Ideal signal generation section 24c, 24g Interference signal acquisition section 24e Reference signal holding unit 28a Test execution control unit (test execution control means) 28b Interference warning unit (interference warning means) 28c Spectrogram generation unit (spectrogram generation means) 28d Display control unit (display control means) 30 Display section 32 Interference warning message 35a Spectrogram 40 Operation unit (setting means) 50 Electromagnetic shielding box 100 DUT (TDMA terminal) S1 Demodulated signal Si ideal signal S11 reference signal Sitf signal (interference signal)

Claims

1. A TDMA measurement device that contains a TDMA terminal that performs short-distance wireless communication by a time division multiple access (TDMA) system as an object to be measured (100) in an electromagnetic shielding box (50) and measures transmission characteristics and reception characteristics of the object to be measured in a wireless environment, A setting means (40) for setting test conditions including a frequency band to be measured; a test execution control means (28a) for executing a transmission performance test for measuring the transmission characteristics and a reception performance test for measuring the reception characteristics by performing short-range wireless communication with the device under test in accordance with a predetermined test procedure; an interference signal detection means (24) for detecting an interference signal exceeding a predetermined threshold output level for a frequency band within the measurement target frequency band set by the setting means during execution of the transmission performance test or the reception performance test; an interference warning means (28b) for, when the interference signal is detected by the interference signal detection means, issuing a warning that the interference signal has been detected in association with the measurement result of the transmission characteristics or the measurement result of the reception characteristics of the device under test; A TDMA measuring device comprising:

2. 2. The TDMA measurement device according to claim 1, wherein the test execution control means executes the transmission performance test, which transmits a transmission command of a desired transmission signal to the device under test and measures the transmission characteristics based on a measurement result of the transmission signal transmitted by the device under test in response to the transmission command, and the reception performance test, which transmits a reception command and a reception test signal to the device under test and measures the reception characteristics based on a reception status notification transmitted by the device under test upon receiving the reception test signal.

3. A TDMA measurement device that contains a TDMA terminal that performs short-range wireless communication by a time division multiple access (TDMA) method as a measured object (100) in an electromagnetic wave shielding box (50) and measures the transmission characteristics and reception characteristics of the measured object in a wireless environment, A setting means (40) for setting test conditions including a frequency band to be measured; a test execution control means (28a) for executing a transmission performance test for measuring the transmission characteristics and a reception performance test for measuring the reception characteristics by performing short-range wireless communication with the device under test in accordance with a predetermined test procedure; an interference signal detection means (24) for detecting an interference signal exceeding a predetermined threshold output level for a frequency band within the measurement target frequency band set by the setting means during execution of the transmission performance test or the reception performance test; an interference warning means (28b) for, when the interference signal is detected by the interference signal detection means, issuing a warning that the interference signal has been detected in association with the measurement result of the transmission characteristics or the measurement result of the reception characteristics of the device under test; Equipped with the test execution control means executes the transmission performance test, which transmits a transmission command of a desired transmission signal to the device under test, and measures the transmission characteristics based on a measurement result of the transmission signal transmitted by the device under test in response to the transmission command, and the reception performance test, which transmits a reception command and a reception test signal to the device under test, and measures the reception characteristics based on a reception status notification transmitted by the device under test that has received the reception test signal; The interference signal detection means an ideal signal generating unit (24a) which receives a demodulated signal (S1) generated by a reception process of the transmission signal from the device under test in the transmission performance test, or a reception process of a signal received from the periphery when the reception test signal is transmitted to the device under test in the reception performance test, and generates an ideal signal (Si) of the demodulated signal based on the demodulated signal; and an interference signal capture unit (24c) that captures a signal (Sitf) obtained by subtracting the ideal signal from the demodulated signal as the interference signal.

4. A TDMA measurement device that contains a TDMA terminal that performs short-range wireless communication by a time division multiple access (TDMA) method as a measured object (100) in an electromagnetic wave shielding box (50) and measures the transmission characteristics and reception characteristics of the measured object in a wireless environment, A setting means (40) for setting test conditions including a frequency band to be measured; a test execution control means (28a) for executing a transmission performance test for measuring the transmission characteristics and a reception performance test for measuring the reception characteristics by performing short-range wireless communication with the device under test in accordance with a predetermined test procedure; an interference signal detection means (24) for detecting an interference signal exceeding a predetermined threshold output level for a frequency band within the measurement target frequency band set by the setting means during execution of the transmission performance test or the reception performance test; an interference warning means (28b) for, when the interference signal is detected by the interference signal detection means, issuing a warning that the interference signal has been detected in association with the measurement result of the transmission characteristics or the measurement result of the reception characteristics of the device under test; Equipped with the test execution control means executes the transmission performance test, which transmits a transmission command of a desired transmission signal to the device under test, and measures the transmission characteristics based on a measurement result of the transmission signal transmitted by the device under test in response to the transmission command, and the reception performance test, which transmits a reception command and a reception test signal to the device under test, and measures the reception characteristics based on a reception status notification transmitted by the device under test that has received the reception test signal; The interference signal detection means a reference signal holding unit (24e) that receives a demodulated signal (S1) generated by a reception process of the transmission signal from the device under test in the transmission performance test, or a reception process of a signal received from the periphery when the reception test signal is transmitted to the device under test in the reception performance test, and holds the demodulated signal (S1) as a reference signal (S11); and an interference signal capture unit (24g) that captures a signal (Sitf) that is a difference between different on-intervals or off-intervals of the demodulated signal and the reference signal as the interference signal.

5. A TDMA measuring device that contains a TDMA terminal that performs short-range wireless communication by a time division multiple access (TDMA) method as a measured object (100) in an electromagnetic wave shielding box (50) and measures the transmission characteristics and reception characteristics of the measured object in a wireless environment, A setting means (40) for setting test conditions including a frequency band to be measured; a test execution control means (28a) for executing a transmission performance test for measuring the transmission characteristics and a reception performance test for measuring the reception characteristics by performing short-range wireless communication with the device under test in accordance with a predetermined test procedure; an interference signal detection means (24) for detecting an interference signal exceeding a predetermined threshold output level for a frequency band within the measurement target frequency band set by the setting means during execution of the transmission performance test or the reception performance test; an interference warning means (28b) for, when the interference signal is detected by the interference signal detection means, issuing a warning that the interference signal has been detected in association with the measurement result of the transmission characteristics or the measurement result of the reception characteristics of the device under test; Equipped with the test execution control means executes the transmission performance test, which transmits a transmission command of a desired transmission signal to the device under test, and measures the transmission characteristics based on a measurement result of the transmission signal transmitted by the device under test in response to the transmission command, and the reception performance test, which transmits a reception command and a reception test signal to the device under test, and measures the reception characteristics based on a reception status notification transmitted by the device under test that has received the reception test signal; the electromagnetic wave shielding box accommodates a Bluetooth terminal that communicates according to the Bluetooth communication standard as the TDMA terminal, The test execution control means performs the transmission performance test and the reception performance test by performing communication between the Bluetooth terminal and the measured object in accordance with the test procedure using the Bluetooth communication standard.

6. A TDMA measurement device that contains a TDMA terminal that performs short-range wireless communication by a time division multiple access (TDMA) method as a measured object (100) in an electromagnetic wave shielding box (50) and measures the transmission characteristics and reception characteristics of the measured object in a wireless environment, A setting means (40) for setting test conditions including a frequency band to be measured; a test execution control means (28a) for executing a transmission performance test for measuring the transmission characteristics and a reception performance test for measuring the reception characteristics by performing short-range wireless communication with the device under test in accordance with a predetermined test procedure; an interference signal detection means (24) for detecting an interference signal exceeding a predetermined threshold output level for a frequency band within the measurement target frequency band set by the setting means during execution of the transmission performance test or the reception performance test; an interference warning means (28b) for, when the interference signal is detected by the interference signal detection means, issuing a warning that the interference signal has been detected in association with the measurement result of the transmission characteristics or the measurement result of the reception characteristics of the device under test; Equipped with The setting means sets, as the measurement target frequency band, a frequency band corresponding to each of a plurality of frequency channels to be hopped that are allocated to a 2.4 GHz band defined by a Bluetooth communication standard; The TDMA measurement device is characterized in that the interference signal detection means measures the interference signal by setting a frequency range of a frequency band corresponding to one of a plurality of frequency channels set by the setting means as a frequency band within the band.

7. A TDMA measurement device that contains a TDMA terminal that performs short-range wireless communication by a time division multiple access (TDMA) method as a measured object (100) in an electromagnetic wave shielding box (50) and measures the transmission characteristics and reception characteristics of the measured object in a wireless environment, A setting means (40) for setting test conditions including a frequency band to be measured; a test execution control means (28a) for executing a transmission performance test for measuring the transmission characteristics and a reception performance test for measuring the reception characteristics by performing short-range wireless communication with the device under test in accordance with a predetermined test procedure; an interference signal detection means (24) for detecting an interference signal exceeding a predetermined threshold output level for a frequency band within the measurement target frequency band set by the setting means during execution of the transmission performance test or the reception performance test; an interference warning means (28b) for, when the interference signal is detected by the interference signal detection means, issuing a warning that the interference signal has been detected in association with the measurement result of the transmission characteristics or the measurement result of the reception characteristics of the device under test; Equipped with The interference warning means displays, as the warning, an interference warning message (32) indicating that the interference signal has been detected and the reliability of the measurement result of the transmission characteristics or the reception characteristics has decreased, in addition to the measurement result of the transmission characteristics or the reception characteristics.

8. a spectrogram generating means (28c) for analyzing a detection result of the interference signal by the interference signal detection means and generating a spectrogram (35a) representing a distribution of the interference signal in terms of a relationship between frequency and signal strength and time based on the analysis result; a display control means (28d) for switching to the interference warning message and displaying the spectrogram in response to a predetermined switching command; 8. The TDMA measurement device according to claim 7, further comprising:

9. A TDMA measurement method for measuring transmission characteristics and reception characteristics of a TDMA terminal that performs short-distance wireless communication by a time division multiple access (TDMA) system as an object to be measured (100) in a wireless environment by using the TDMA measurement device according to claim 1, the method comprising: A setting step (S2) of setting test conditions including a frequency band to be measured; a test execution control step (S4 to S6, S20 to S22) for executing a transmission performance test for measuring the transmission characteristics and a reception performance test for measuring the reception characteristics by performing short-range wireless communication with the device under test according to a predetermined test procedure; an interference signal detection step (S7, S23) of detecting an interference signal exceeding a predetermined threshold output level for a frequency band within the measurement target frequency band set in the setting step during execution of the transmission performance test or the reception performance test; an interference warning step (S10, S26) of issuing a warning that the interference signal has been detected in association with the measurement result of the transmission characteristic or the measurement result of the reception characteristic of the device under test when the interference signal is detected by the interference signal detection step; A TDMA measurement method comprising:

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