Measurement system, transmission system, and reception system

Abstract

To provide a measurement system that, in measurement of the characteristics of a millimeter-wave band antenna in a multi-wave environment, can extend the applicability of measurement without decreasing frequency stability.SOLUTION: A measurement system comprises a transmission system and a reception system. The transmission system receives a common reference signal wirelessly transmitted from an external common device, and on the basis of the common reference signal, generates and wirelessly transmits a test signal for measuring the characteristics of an antenna to be measured, while switching between a plurality of transmission frequencies within a predetermined frequency range at a predetermined frequency switching timing. The reception system receives the common reference signal wirelessly transmitted from the external common device, receives the test signal transmitted from the transmission system, and measures the characteristics of the antenna, on the basis of the common reference signal, information on the plurality of transmission frequencies within the predetermined frequency range, and a trigger signal corresponding to the predetermined frequency switching timing.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a measurement system for measuring the characteristics of an antenna, a transmission system and a reception system. [Background technology]

[0002] Conventionally, as a measurement system of this kind, a system is known that includes a signal generator (SG) of a transmission system that transmits a high-frequency test signal in the millimeter wave band (30 GHz to 300 GHz) and a vector network analyzer (VNA) of a reception system that analyzes the test signal received by the antenna to be measured, and that connects the SG and the VNA by multiple cables for transmitting control signals. With this system, the transmission system is installed outside the reception system and away from the reception system, and the reception system is directly connected to the antenna to be measured, bypassing the S-parameter set, making it possible to perform measurements in a millimeter wave band multi-wave environment where the distance between the input and output ends of the test signal is long.

[0003] Non-cited document 1 discloses a system in which the SG is installed outside the transmission system and the antenna to be measured is directly connected to the VNA, and control commands and trigger signals (frequency switching trigger signal and frequency switching busy signal) are transmitted between the SG and the VNA via a control wireless line. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Ryo Yamaguchi, Koichi Serizawa, Kazuma Toyomimoto, Masayuki Miyashita, "Doppler Spectrum of Tandem V2V Direct Communication", IEICE Transactions on Information and Communication Engineers, Vol. J103-B, No. 11, pp. 515-527. Summary of the Invention [Problem to be solved by the invention]

[0005] The above conventional system has the following problems. That is, the above conventional system has a problem that the range of application is limited because of the wired connection between the SG and the VNA using multiple cables. Also, the system of Non-Patent Document 1 is premised on stabilizing the quality of the wireless line that transmits the control command and trigger signal, so the range of application is limited to measurements in open sites, between vehicles traveling in a tandem, etc. [Means for solving the problem]

[0006] A system according to one aspect of the present invention is a measurement system for measuring characteristics of a millimeter wave antenna, comprising: a transmission system that receives a common reference signal wirelessly transmitted from an external common device, and generates and wirelessly transmits a test signal for measuring characteristics of an antenna to be measured while switching among a plurality of transmission frequencies in a predetermined frequency range at a predetermined frequency switching timing based on the common reference signal, and a reception system that receives the common reference signal wirelessly transmitted from the external common device, and receives the test signal transmitted from the transmission system based on the common reference signal, information on the plurality of transmission frequencies in the predetermined frequency range, and a trigger signal corresponding to the predetermined frequency switching timing, to measure the characteristics of the antenna.

[0007] A system according to another aspect of the present invention is a transmission system constituting a measurement system for measuring characteristics of a millimeter wave band antenna, comprising: means for receiving a common reference signal wirelessly transmitted from an external common device; and means for generating and wirelessly transmitting a test signal for measuring characteristics of an antenna to be measured while switching a plurality of transmission frequencies in a predetermined frequency range at a predetermined frequency switching timing based on the common reference signal.

[0008] A system according to another aspect of the present invention is a receiving system constituting a measurement system for measuring characteristics of a millimeter wave band antenna, the receiving system including: means for receiving the common reference signal wirelessly transmitted from an external common device; and means for receiving a test signal transmitted from a transmitting system and measuring characteristics of the antenna based on the common reference signal, information on a plurality of transmission frequencies in a predetermined frequency range, and a trigger signal corresponding to a predetermined frequency switching timing.

[0009] In the measurement system, the transmission system may include a reference signal generating unit that generates a frequency reference signal and a synchronization reference signal based on the common reference signal, a trigger signal generating unit that generates a trigger signal corresponding to the frequency switching timing based on the synchronization reference signal, a signal generator that switches the transmission frequency based on the frequency reference signal and the trigger signal to generate the test signal, and a transmission antenna that transmits the radio wave of the test signal generated by the signal generator. Also, the reception system may include a reference signal generating unit that generates a frequency reference signal and a synchronization reference signal based on the common reference signal, a trigger signal generating unit that generates a trigger signal corresponding to the frequency switching timing based on the synchronization reference signal, and a vector network analyzer that measures characteristics of the antenna to be measured based on a received signal output from the antenna to be measured that receives the radio wave of the test signal transmitted from the transmission system, the trigger signal, and information on a plurality of transmission frequencies in the predetermined frequency range.

[0010] In the measurement system, the reference signal generating unit of the transmitting system and the reference signal generating unit of the receiving system may each have a GNSS (Global Navigation Satellite System) receiver that outputs a received signal of the common reference signal, and a rubidium oscillator that generates the frequency reference signal and the synchronization reference signal based on the received signal of the GNSS receiver.

[0011] In the measurement system, the vector network analyzer may receive a trigger signal from the trigger signal generating unit for each of a plurality of transmission frequencies in the predetermined frequency range, and operate using the trigger signal as a measurement point trigger.

[0012] In the measurement system, the antenna to be measured is an antenna that has directionality and can be rotated in predetermined rotation angle steps, and the vector network analyzer may receive the trigger signal from the trigger signal generating unit for each transmission frequency in the predetermined frequency range and for each rotation angle step of the antenna. Effect of the Invention

[0013] According to the present invention, it is possible to expand the range of application of measurement without deteriorating frequency stability in measurement of the characteristics of millimeter wave band antennas in a multipath environment. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram showing an example of a configuration of a main part of a measurement system having a wired VNA configuration according to a reference example. [Diagram 2] FIG. 2 is a diagram showing an example of an observation of the waveform of a trigger signal transmitted and received in the measurement system configured with a wired VNA in FIG. [Diagram 3] FIG. 3 is a diagram showing an example of a configuration of a main part of a measurement system having a virtual connection VNA configuration according to an embodiment. [Figure 4] FIG. 4 is a diagram showing an example of an observation of the waveform of a trigger signal transmitted and received in the measurement system having the virtual connection VNA configuration of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that each drawing merely shows the shape, size, and positional relationship in a schematic manner to the extent that the contents of the present invention can be understood, and therefore the present invention is not limited to the shape, size, and positional relationship exemplified in each drawing. In addition, the numerical values ​​exemplified below are merely preferred examples of the present invention, and therefore the present invention is not limited to the numerical values ​​exemplified.

[0016] The system according to the embodiment described in this specification is a measurement system configured as a vector network analyzer (hereinafter also referred to as "VNA") with a virtually connected external transmission system that can expand the range of measurement application without deteriorating frequency stability in measuring the characteristics of an antenna in the millimeter wave band (30 to 300 GHz) in a multi-wave environment. Also, the measurement system according to this embodiment can efficiently evaluate the characteristics of a millimeter wave band antenna in a multi-wave environment.

[0017] VNA is often used for antenna measurement in multipath environments. VNA has advantages such as phase measurement, multichannel measurement, ultra-wideband measurement, real-time high-resolution delay measurement by frequency sweep, frequency conversion measurement, calibration function, and high dynamic range associated with narrowband signals, making it a practical measuring instrument for millimeter-wave field measurements. In a typical configuration of an antenna measurement system using VNA, the three elements of the VNA, the transmission system, the reception system, and the S-parameter set, are mounted in the same housing. In cases where the input / output end distance is short, such as in microwave devices, this typical configuration is not a problem, but in antenna measurements in large anechoic chambers and open sites, the transmission antenna distance is long, so a configuration is used in which the VNA's transmission system is connected externally, the S-parameter set is bypassed, and the VNA of the reception system is directly connected to the antenna to be measured for reception (hereinafter referred to as the "VNA direct connection configuration"). It is considered that the use of the external connection of the transmission system and the VNA direct connection configuration is effective for evaluating antenna characteristics and direction of arrival characteristics in a multipath environment.

[0018] Fig. 1 is a diagram showing an example of the main configuration of a measurement system 90 having a wired VNA according to a reference example. In the measurement system of Fig. 1, control commands and trigger signals are transmitted and received between the VNAs of the transmission system and the VNAs of the reception system via cables.

[0019] 1, the measurement system 90 includes a transmission system 910 constituting a transmission system, and a reception system 920 constituting a reception system. The transmission system 910 includes a signal generator (SG) 911 that generates a test signal by switching a transmission frequency based on a frequency reference signal (10 MHz reference signal) and a trigger signal (frequency switching trigger signal) corresponding to the frequency switching timing, and a transmission antenna 912 that transmits the radio wave of the test signal generated by the signal generator 911.

[0020] The receiving system 920 includes a VNA 921 that measures the characteristics of the antenna 200 to be measured based on a sweep trigger signal, and generates and outputs a sweep trigger signal based on an angle pulse output at each predetermined rotation angle from a rotation drive unit 210 that rotates the antenna 200 in the antenna device 20.

[0021] Here, there are two types of measurement control methods using a VNA: a trigger method and a command method. In the trigger method, both the transmitting and receiving systems (the transmitting system and the receiving system) have a sweep frequency list in advance, and the frequency switching instruction and the switching completion report are handshake using a trigger signal, which is a faster operation than the command method. The trigger method has two trigger modes: a sweep trigger mode and a point trigger mode. The former, the sweep trigger mode, is used in the measurement system 90 with the wired connection VNA configuration in FIG. 1, and the latter, the point trigger mode, is used in the measurement system 10 with the virtual connection VNA configuration in FIG. 3, which will be described later. On the other hand, the command method is slow because it sets the sweep frequency each time using a control command, and is not used in the measurement system 90 with the wired connection VNA configuration in FIG. 1 or the measurement system 10 with the virtual connection VNA configuration in FIG. 3, which will be described later.

[0022] The transmitting system 910 and the receiving system 920 are connected by a cable group 930 consisting of four cables. As shown in FIG. 1, the cable group 930 includes a LAN cable 931 for transmitting and receiving a control command, a cable 932 for transmitting and receiving a frequency switching busy signal, a cable 933 for transmitting and receiving a frequency switching trigger signal, and a cable 934 for transmitting and receiving a frequency reference signal (10 MHz reference signal). A sweep trigger signal output from the measurement pulse generator 922 for each predetermined rotation angle of the antenna 200 is input to the VNA 921 as an external trigger. A frequency switching trigger signal output from the VNA 921 based on the external trigger (sweep trigger signal) is transmitted via the cable 933 and input to the signal generator (SG) 911. A frequency switching busy signal output from the signal generator (SG) 911 is transmitted via the cable 932 and input to the VNA 921. Furthermore, a frequency reference signal (10 MHz reference signal) output from a signal generator (SG) 911 is transmitted via a cable 934 and input to a VNA 921 .

[0023] Fig. 2 is a diagram showing an example of observed waveforms of trigger signals in a sweep trigger mode transmitted and received in the measurement system configured with a wired VNA in Fig. 1. In Fig. 2, when the VNA 921 on the receiving system side receives an external trigger sweep trigger signal (the signal in the upper part of the figure) from the measurement pulse generator 922, it measures the received signal from the antenna 200 for the initial frequency (the first frequency of the sweep) at a predetermined measurement time Tm. When the measurement ends, it transmits a frequency switching trigger signal (the signal in the middle part of the figure) to the signal generator (SG) 911. In the observation example in Fig. 2, the first two frequency switching trigger signals during the sweep of 201 points per rotation angle are observed. The signal generator (SG) 911 on the transmitting system side transmits a frequency switching busy signal (the signal in the lower part of the figure) to the VNA 921 at the same time as the start of frequency switching. After a predetermined frequency switching time (Ts) has elapsed and VNA 911 detects the falling edge of the frequency switching busy signal (switching completed), it waits for a certain period of time (waiting time Tw in the figure) and then measures the received signal from antenna 200 for the next new frequency.

[0024] In the measurement system with a wired VNA configuration for reference shown in Figures 1 and 2, the transmitting system 910 and the receiving system 920 must be connected with four cables 931 to 934, which limits the range of application of antenna measurements in millimeter wave band multipath environments.

[0025] As a method that does not use the above-mentioned wired connection, a wireless connection method may be considered in which the transmitting system 910 and the receiving system 920 are connected wirelessly instead of by a wired connection, and the above-mentioned control command, frequency switching busy signal, frequency switching trigger signal, and frequency reference signal (10 MHz reference signal) are transmitted and received via a wireless line. This wireless connection method can also be applied to evaluation of propagation characteristics in, for example, tandem vehicle-to-vehicle communication. However, the wireless connection method is premised on stabilization of the quality of the wireless line used to transmit the control command and various signals, so the scope of application is limited to open sites, tandem vehicle-to-vehicle communication, etc.

[0026] In order to further expand the scope of application of millimeter wave band multipath environment antenna measurements, the measurement system of this embodiment is configured to apply a method of virtually connecting a transmission system and a receiving system (VNA) as shown below (hereinafter also referred to as a ``virtual connection VNA configuration'') as an extended wireless connection method.

[0027] Fig. 3 is a diagram showing an example of a configuration of a main part of a measurement system 10 having a virtually connected VNA configuration according to an embodiment. In the example of Fig. 3, a case is described in which the external common device is a GNSS satellite and the common reference signal is a GNSS signal received from the GNSS satellite, but the external common device may be a device other than a GNSS satellite, and the common reference signal may be a signal received from a common device other than a GNSS satellite.

[0028] 3, the measurement system 10 operates in the point trigger mode described above and includes a transmission system, a transmission system, and a reception system, a reception system. The transmission system 110 receives a common reference signal (GNSS signal) wirelessly transmitted from an external common device (GNSS satellite), and generates and wirelessly transmits a test signal for measuring the characteristics of the antenna 200 to be measured while switching a plurality of transmission frequencies in a predetermined frequency range at a predetermined frequency switching timing based on the common reference signal. The reception system 120 receives the common reference signal wirelessly transmitted from an external common device (GNSS satellite), and receives the test signal transmitted from the transmission system 110 based on the common reference signal, information on a plurality of transmission frequencies in a predetermined frequency range, and a trigger signal (measurement point trigger signal) corresponding to the predetermined frequency switching timing, to measure the characteristics of the antenna 200.

[0029] The transmission system 110 includes a reference signal generating unit 114 that generates a frequency reference signal and a synchronization reference signal based on a common reference signal (GNSS signal), a measurement pulse generator 113 as a trigger signal generating unit that generates a trigger signal corresponding to the frequency switching timing based on the synchronization reference signal, a signal generator (SG) 111 that switches the transmission frequency based on the frequency reference signal and the trigger signal to generate a test signal, and a transmitting antenna 112 that transmits the radio waves of the test signal generated by the signal generator (SG) 111.

[0030] The reference signal generating unit 114 has a GNSS receiver 115 that outputs a received signal of a common reference signal (GNSS signal), and a rubidium (Rb) oscillator 116 that generates the frequency reference signal and the synchronization reference signal based on the received signal of the GNSS receiver 115. The frequency reference signal is, for example, a 10 MHz reference signal, and the synchronization reference signal is, for example, a 1 PPS (Pulse per Second) signal.

[0031] The receiving system 120 includes a reference signal generating unit 123 that generates a frequency reference signal and a synchronization reference signal based on a common reference signal (GNSS signal), a measurement pulse generator 122 as a trigger signal generating unit that generates a trigger signal corresponding to the frequency switching timing based on the synchronization reference signal, and a VNA (vector network analyzer) 121 that measures the characteristics of the antenna 200 to be measured based on a received signal output from the antenna 200 to be measured that has received the radio wave of the test signal transmitted from the transmitting system 110, the trigger signal, and information on a plurality of transmission frequencies in the specified frequency range.

[0032] The reference signal generating unit 123 includes a GNSS receiver 115 that outputs a received signal of a common reference signal (GNSS signal), and a rubidium (Rb) oscillator 116 that generates a frequency reference signal and a synchronization reference signal based on the received signal of the GNSS receiver 115. The frequency reference signal is, for example, a 10 MHz reference signal, and the synchronization reference signal is, for example, a 1 PPS (Pulse per Second) signal.

[0033] The VNA 121 receives a measurement point trigger signal from the measurement pulse generator 122 and operates using the measurement point trigger signal as a measurement point trigger.

[0034] The antenna 200 of the antenna device 20 to be measured is an antenna that has directivity and can be rotated in a predetermined rotation angle step. The VNA 121 receives the measurement point trigger signal from the measurement pulse generator 122 for each transmission frequency and for each rotation angle step of the antenna 200 for a plurality of transmission frequencies in a predetermined frequency range.

[0035] Fig. 4 is a diagram showing an example of observing the waveform of a trigger signal transmitted and received in the measurement system 10 having the virtual connection VNA configuration of Fig. 3. Note that, for reference, Fig. 4 also shows a frequency busy signal output from the signal generator (SG) 111, but this is not used in the measurement system 10 of this embodiment.

[0036] In the measurement system 10 with the virtual connection VNA configuration, the behavior of each trigger signal (measurement point trigger signal and frequency switching trigger signal) shown in Fig. 4 was observed, and it was found that each trigger signal is transmitted at a specific period every time the settings are changed, and that the reproducibility is also high. In general antenna measurements, the settings of the sweep frequency, number of points, IF (intermediate frequency) bandwidth, etc. are not dynamically changed but are fixed, so in the configuration of this embodiment, each trigger signal (measurement point trigger signal and frequency switching trigger signal) is emulated by measurement pulse generators 113, 122 installed in both the transmitting system 110 and the receiving system 120, making it possible to eliminate cable connections.

[0037] In the measurement system 10 having the virtually connected VNA configuration of this embodiment, as described above, the transmission system 110 of the transmission system and the reception system 120 of the reception system are provided with separate GNSS receivers 115, 124, and the signal generator (SG) 111 of the transmission system and the VNA 121 of the reception system are connected with separate rubidium oscillators (Rb) and measurement pulse generators 113, 122. Since the transmission system (transmission system) 110 is not controlled by the VNA 121, it uses a so-called continuous sweep method in which the test signal is transmitted by sweeping the frequency at a timing synchronized with the GNSS 1PPS signal as a reference. Similarly, the VNA 121 (reception system) also receives the test signal by sweeping the frequency at a timing based on the GNSS 1PPS signal, so that the transmission and reception of the test signal are synchronized.

[0038] In addition, in the measurement system 10 of the present embodiment having a virtually connected VNA configuration, unlike the measurement system 90 having a wired connected VNA configuration of the reference example of Figure 1 described above, a point trigger mode is adopted, and a measurement point trigger signal (the signal in the upper part of Figure 4) is provided to the VNA 121 as an external trigger for each sweep frequency point.

[0039] 1, the VNA 121 receives an external trigger for each predetermined rotation angle (e.g., every 1°) of the antenna 200, and the system as a whole internally issues a frequency switching trigger signal and a frequency switching busy signal. On the other hand, in the point trigger mode of the measurement system 10 of the virtual connection VNA configuration of this embodiment, for a plurality of sweep frequencies (transmission frequencies) in a predetermined frequency range, a total of 72360 (=360×201) external triggers are used for each predetermined rotation angle (e.g., every 1°) of the antenna 200 and for each sweep frequency in each of the transmission system 110 and the reception system 120. For example, a total of 72,360 (= 360 × 201) frequency switching trigger signals are input to the signal generator (SG) 111 of the transmitting system 110 as external triggers, and a total of 72,360 (= 360 × 201) measurement point trigger signals are input to the VNA 121 of the receiving system 120 as external triggers.

[0040] As described above, in the measurement system 10 with the virtually connected VNA configuration of this embodiment, since there is no control of the transmission system (transmission system) 110, no LAN cable for control commands is required, since a synchronized trigger signal is available, no cable for a trigger signal is required, and since rubidium oscillators 116 and 125 with GNSS receivers are provided, no cable for a frequency reference signal is required, resulting in a configuration without any cables at all. Therefore, it is possible to expand the range of application of antenna measurement in a millimeter wave band multiple wave environment.

[0041] Table 1 shows a measurement example of frequency stability (fluctuation of received signal) in the frequency band of 8.5 GHz to 300 GHz when operating with the measurement system 10 with the virtual connection VNA configuration of this embodiment. The values ​​in parentheses in the table are the fluctuation width of the received signal. For comparison, Table 1 also shows a measurement example of the measurement system 90 with the wired connection VNA configuration of the reference example. In the wired connection VNA configuration of the reference example, a 10 MHz reference signal of the transmission system (transmission system) was used. In the virtual connection VNA configuration of this embodiment, measurement examples are shown for (A) the case where a reference signal from a built-in signal source is used, and (B) the case where a reference signal from a rubidium oscillator of the configuration of FIG. 3 is used. The case of the wired connection VNA configuration (IF bandwidth 10 kHz) in each frequency band is shown as a reference value (0 dB).

[0042] [Table 1]

[0043] As shown in Table 1, when using the reference signal from the built-in signal source (A), a frequency shift occurred and a significant drop in the reception level (shown in bold in the table) was observed. On the other hand, when using the reference signal from the rubidium oscillator in the configuration in Figure 3 (B), high frequency stability comparable to that of the wired VNA configuration was confirmed, demonstrating its effectiveness.

[0044] As described above, according to this embodiment, it is possible to expand the range of application of measurement without deteriorating frequency stability in measuring the characteristics of millimeter wave band antennas in a multipath environment.

[0045] In addition, the present invention can expand the scope of application of measurements without reducing frequency stability when measuring the characteristics of millimeter wave band antennas in multi-wave environments, thereby contributing to the achievement of Goal 9 of the Sustainable Development Goals (SDGs), which is to "build resilient infrastructure, promote industry, innovation and infrastructure."

[0046] It should be noted that the process steps and components of the measurement system described herein may be implemented by various means. For example, the steps and components may be implemented in hardware, firmware, software, or a combination thereof.

[0047] For hardware implementations, the processing units and other means used to realize the above steps and components in the entity (e.g., signal generator, network analyzer, oscillator) may be implemented in one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processors (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, electronic devices, other electronic units designed to perform the functions described herein, computers, or combinations thereof.

[0048] Also, for firmware and / or software implementation, the means such as processing units used to realize the above components may be implemented with programs (e.g., codes such as procedures, functions, modules, instructions, etc.) that execute the functions described herein. In general, any computer / processor readable medium tangibly embodying firmware and / or software codes may be used to implement the means such as processing units used to realize the above steps and components described herein. For example, the firmware and / or software codes may be stored in a memory and executed by a computer or processor, for example in a controller. The memory may be implemented within the computer or processor, or may be implemented externally to the processor. Also, the firmware and / or software codes may be stored in a computer or processor readable medium, such as a random access memory (RAM), a read-only memory (ROM), a non-volatile random access memory (NVRAM), a programmable read-only memory (PROM), an electrically erasable programmable read-only memory (EEPROM), a flash memory, a floppy disk, a compact disk (CD), a digital versatile disk (DVD), a magnetic or optical data storage device, etc. The code may be executed by one or more computers or processors and may cause the computers or processors to perform certain aspects of the functionality described herein.

[0049] The medium may be a non-transitory recording medium. The code of the program may be in any format as long as it can be read and executed by a computer, a processor, or another device or machine, and the format is not limited to a specific format. For example, the code of the program may be any of source code, object code, and binary code, or may be a mixture of two or more of these codes.

[0050] Moreover, the description of the embodiments disclosed herein is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to the present disclosure will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of the present disclosure. Thus, the present disclosure is not intended to be limited to the examples and designs described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. [Explanation of symbols]

[0051] 10: Measurement system 20: Antenna device 110: Transmission system 112: Transmitting antenna 113: Measurement pulse generator 114: Reference signal generating section 115: GNSS receiver 116: Rubidium oscillator 120: Receiving system 122: Measurement pulse generator 123: Reference signal generator 124: Receiver 125: Rubidium oscillator 200: Antenna 210: Rotation drive unit

Claims

1. A measurement system for measuring characteristics of a millimeter wave antenna, comprising: a transmission system that receives a common reference signal wirelessly transmitted from an external common device, and generates and wirelessly transmits a test signal for measuring characteristics of an antenna to be measured while switching a plurality of transmission frequencies in a predetermined frequency range at a predetermined frequency switching timing based on the common reference signal; a receiving system that receives the common reference signal wirelessly transmitted from the external common device, and receives the test signal transmitted from the transmitting system based on the common reference signal, information on a plurality of transmission frequencies in the predetermined frequency range, and a trigger signal corresponding to the predetermined frequency switching timing, to measure characteristics of the antenna; A measurement system comprising:

2. 2. The measurement system of claim 1, The transmission system includes: a reference signal generating unit that generates a frequency reference signal and a synchronization reference signal based on the common reference signal; a trigger signal generating unit that generates a trigger signal corresponding to the frequency switching timing based on the synchronization reference signal; a signal generator that switches the transmission frequency based on the frequency reference signal and the trigger signal to generate the test signal; a transmitting antenna for transmitting the radio wave of the test signal generated by the signal generator, The receiving system comprises: a reference signal generating unit that generates a frequency reference signal and a synchronization reference signal based on the common reference signal; a trigger signal generating unit that generates a trigger signal corresponding to the frequency switching timing based on the synchronization reference signal; a vector network analyzer that measures characteristics of the antenna to be measured based on a received signal output from the antenna to be measured that receives the radio wave of the test signal transmitted from the transmission system, the trigger signal, and information on a plurality of transmission frequencies in the predetermined frequency range, Measurement system.

3. 3. The measurement system of claim 2, The transmitting system and the receiving system each have a Global Navigation Satellite System (GNSS) receiver that outputs a received signal of the common reference signal; The reference signal generating unit of the transmission system and the reference signal generating unit of the receiving system are rubidium oscillators that generate the frequency reference signal and the synchronization reference signal based on the received signal of the GNSS receiver, Measurement system.

4. In the measurement system according to claim 2 or 3, The vector network analyzer comprises: the trigger signal generating unit inputs the trigger signal for each of a plurality of transmission frequencies in the predetermined frequency range; operating the trigger signal as a measurement point trigger; Measurement system.

5. 5. The measurement system of claim 4, The antenna to be measured is an antenna that has directivity and can be rotated in predetermined rotation angle steps, the vector network analyzer receives the trigger signal from the trigger signal generating unit for each of a plurality of transmission frequencies in the predetermined frequency range and for each rotation angle step of the antenna; Measurement system.

6. A transmission system constituting a measurement system for measuring characteristics of a millimeter wave antenna, comprising: A means for receiving a common reference signal wirelessly transmitted from an external common device; a means for generating and wirelessly transmitting a test signal for measuring characteristics of an antenna under test while switching a plurality of transmission frequencies in a predetermined frequency range at a predetermined frequency switching timing based on the common reference signal; A transmission system comprising:

7. A receiving system constituting a measurement system for measuring characteristics of a millimeter wave antenna, comprising: means for receiving the common reference signal wirelessly transmitted from an external common device; a means for receiving a test signal transmitted from a transmission system and measuring characteristics of the antenna based on the common reference signal, information on a plurality of transmission frequencies in a predetermined frequency range, and a trigger signal corresponding to a predetermined frequency switching timing; A receiving system comprising:

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