US-12625196-B2 - Detection apparatus and detection method

US12625196B2US 12625196 B2US12625196 B2US 12625196B2US-12625196-B2

Abstract

A detection apparatus according to the present disclosure includes a signal output unit configured to output a measurement signal that includes a component having a first frequency to a transmission line, a signal measurement unit configured to measure a response signal, from the transmission line, to the measurement signal output from the signal output unit and a processing unit configured to generate a difference signal that is a difference between the response signal measured by the signal measurement unit and a reference signal that is based on the measurement signal, calculate an index value that indicates a strength of a correlation between the reference signal and the difference signal, and detect an abnormality in the transmission line on the basis of the calculated index value.

Inventors

Satoru Sakurazawa
Masato Izawa
Isao Kato
Takumi Asaina
Shota Shimizu
Kanata Nishida

Assignees

SUMITOMO ELECTRIC INDUSTRIES, LTD.

Dates

Publication Date: 20260512
Application Date: 20220516
Priority Date: 20210602

Claims (20)

1 . A detection apparatus comprising: signal output circuitry configured to output a measurement signal that includes a component having a first frequency to a transmission line; signal measurement circuitry configured to measure a response signal, from the transmission line, to the measurement signal output from the signal output circuitry; and processing circuitry configured to generate a difference signal that is a difference between the response signal measured by the signal measurement circuitry and a reference signal that is based on the measurement signal, calculate an index value that indicates a strength of a correlation between the reference signal and the generated difference signal by performing correlation processing using, as direct operands to the correlation processing, (i) the reference signal that is based on the measurement signal and (ii) the generated difference signal that is the difference between the response signal measured by the signal measurement circuitry and the reference signal that is based on the measurement signal, and detect an abnormality in the transmission line on the basis of the calculated index value.
2 . The detection apparatus according to claim 1 , wherein the processing circuitry is configured to calculate, as the index value, a phase difference between (i) a component having the first frequency and included in the reference signal and (ii) a component having the first frequency and included in the generated difference signal.
3 . The detection apparatus according to claim 1 , wherein the processing circuitry is configured to calculate, as the index value, a reflection coefficient between the reference signal and the generated difference signal.
4 . The detection apparatus according to claim 1 , wherein the processing circuitry is configured to calculate the index value by using (i) an output signal output from a first filter in response to input, into the first filter, of a multiplication signal obtained from the generated difference signal and the reference signal, the first filter being configured to extract a direct-current component, and (ii) an output signal output from a second filter in response to input, into the second filter, of a multiplication signal obtained from the generated difference signal and a signal that is obtained by shifting a phase of a component having the first frequency and included in the reference signal by π/2, the second filter being configured to extract a direct-current component.
5 . The detection apparatus according to claim 1 , wherein the processing circuitry is configured to calculate the index value by using an output signal output from a third filter in response to input, into the third filter, of a multiplication signal obtained from the generated difference signal and a signal that includes a component having a second frequency different from the first frequency, the third filter being configured to extract a component having a difference frequency between the first frequency and the second frequency.
6 . The detection apparatus according to claim 2 , wherein the processing circuitry is configured to calculate the phase difference by using an argument of a complex analysis signal of the reference signal and an argument of a complex analysis signal of the generated difference signal.
7 . The detection apparatus according to claim 1 , wherein the reference signal is a signal obtained by making a delay adjustment to the measurement signal.
8 . The detection apparatus according to claim 7 , wherein a delay amount of the reference signal relative to the measurement signal is allowed to be changed and set.
9 . The detection apparatus according to claim 1 , wherein the reference signal is the response signal measured by the signal measurement circuitry upon a steady-state time.
10 . The detection apparatus according to claim 1 , wherein the processing circuitry is configured to detect a position of occurrence of the abnormality.
11 . A detection method performed in a detection apparatus, comprising: outputting a measurement signal that includes a component having a first frequency to a transmission line; measuring a response signal, from the transmission line, to the measurement signal; generating, with processing circuitry, a difference signal that is a difference between the response signal and a reference signal that is based on the measurement signal; calculating, with the processing circuitry, an index value that indicates a strength of a correlation between the reference signal and the generated difference signal by performing correlation processing using, as direct operands to the correlation processing, (i) the reference signal that is based on the measurement signal and (ii) the generated difference signal that is the difference between the response signal and the reference signal that is based on the measurement signal; and detecting, with the processing circuitry, an abnormality in the transmission line on the basis of the calculated index value.
12 . The detection method according to claim 11 , wherein the calculating includes calculating, as the index value, a phase difference between (i) a component having the first frequency and included in the reference signal and (ii) a component having the first frequency and included in the generated difference signal.
13 . The detection method according to claim 11 , wherein the calculating includes calculating, as the index value, a reflection coefficient between the reference signal and the generated difference signal.
14 . The detection method according to claim 11 , wherein the calculating includes calculating the index value by using (i) an output signal output from a first filter in response to input, into the first filter, of a multiplication signal obtained from the generated difference signal and the reference signal, the first filter being configured to extract a direct-current component, and (ii) an output signal output from a second filter in response to input, into the second filter, of a multiplication signal obtained from the generated difference signal and a signal that is obtained by shifting a phase of a component having the first frequency and included in the reference signal by π/2, the second filter being configured to extract a direct-current component.
15 . The detection method according to claim 11 , wherein the calculating includes calculating the index value by using an output signal output from a third filter in response to input, into the third filter, of a multiplication signal obtained from the generated difference signal and a signal that includes a component having a second frequency different from the first frequency, the third filter being configured to extract a component having a difference frequency between the first frequency and the second frequency.
16 . The detection method according to claim 12 , wherein the calculating includes calculating the phase difference by using an argument of a complex analysis signal of the reference signal and an argument of a complex analysis signal of the generated difference signal.
17 . The detection method according to claim 11 , wherein the reference signal is a signal obtained by making a delay adjustment to the measurement signal.
18 . The detection method according to claim 17 , wherein a delay amount of the reference signal relative to the measurement signal is allowed to be changed and set.
19 . The detection method according to claim 11 , wherein the reference signal that is the response signal measured upon a steady-state time.
20 . The detection method according to claim 11 , further comprising detecting a position of occurrence of the abnormality.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS The present application is based on PCT filing PCT/JP2022/020405, filed May 16, 2022, which claims priority from Japanese Patent Application No. 2021-092768, filed Jun. 2, 2021, the disclosure of each is incorporated herein in its entirety by reference. TECHNICAL FIELD The present disclosure relates to a detection apparatus and a detection method. BACKGROUND PTL 1 (Japanese Unexamined Patent Application Publication No. 2015-536456) discloses a method for monitoring a condition of an electrical cable. The method includes applying a broadband signal wave to an end of the electrical cable, wherein the broadband signal wave is phase and amplitude modulated, acquiring at the end of the cable the broadband signal wave transmitted and reflected by the electrical cable, and identifying impedance characteristics by using the acquired broadband signal wave. For example, PTL 2 (Japanese Unexamined Patent Application Publication No. 2018-179531) discloses a transmission apparatus as follows. Specifically, in the transmission apparatus in which a first card and a second card are connected via a connector, the transmission apparatus includes a signal generation unit that outputs an AC signal having a frequency higher than the transmission rate of data input to the transmission apparatus, and a judgment unit that receives the AC signal via the connector and judges whether the first card and the second card are fitted with the connector on the basis of the power level of the received AC signal. PRIOR ART DOCUMENT Patent Literature PTL 1: Japanese Unexamined Patent Application Publication No. 2015-536456PTL 2: Japanese Unexamined Patent Application Publication No. 2018-179531 SUMMARY A detection apparatus according to the present disclosure includes a signal output unit configured to output a measurement signal that includes a component having a first frequency to a transmission line; a signal measurement unit configured to measure a response signal, from the transmission line, to the measurement signal output from the signal output unit; and a processing unit configured to generate a difference signal that is a difference between the response signal measured by the signal measurement unit and a reference signal that is based on the measurement signal, calculate an index value that indicates a strength of a correlation between the reference signal and the difference signal, and detect an abnormality in the transmission line on the basis of the calculated index value. A detection method according to the present disclosure is a detection method performed in a detection apparatus. The method includes outputting a measurement signal that includes a component having a first frequency to a transmission line; measuring a response signal, from the transmission line, to the measurement signal; and calculating an index value that indicates a strength of a correlation between the measured response signal and a reference signal based on the measurement signal and detecting an abnormality in the transmission line on the basis of the calculated index value. One aspect of the present disclosure can be achieved not only as a detection apparatus including such a characteristic processing unit but also as a semiconductor integrated circuit that achieves a part or all of the detection apparatus or as a system including the detection apparatus. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a configuration of a communication system according to a first embodiment of the present disclosure. FIG. 2 is a diagram showing a configuration of a relay apparatus according to the first embodiment of the present disclosure. FIG. 3 is a diagram showing a simulation result of a response signal measured by a signal measurement unit in the relay apparatus according to the first embodiment of the present disclosure. FIG. 4 is a diagram showing a simulation result of an argument of a complex analysis signal calculated by a processing unit in the relay apparatus according to the first embodiment of the present disclosure. FIG. 5 is a diagram showing a method of specifying a position of occurrence of a disconnection by the processing unit in the relay apparatus according to the first embodiment of the present disclosure. FIG. 6 is a diagram showing a simulation result of a distance calculated by the processing unit in the relay apparatus according to the first embodiment of the present disclosure. FIG. 7 is a flowchart defining an example of an operation procedure when the relay apparatus according to the first embodiment of the present disclosure performs detection processing. FIG. 8 is a diagram showing a configuration of a relay apparatus according to a second embodiment of the present disclosure. FIG. 9 is a flowchart defining an example of an operation procedure when the relay apparatus according to the second embodiment of the present disclosure performs detection processing. FIG. 10 is a diagram showi