JP6417671B2 - Electronic device, noise suppression system, and noise suppression method - Google Patents

Description

  The present invention relates to an electronic device, a noise suppression system, and a noise suppression method.

  Filters have been used as countermeasures against unnecessary radiation noise from electric signal cables connected to electronic devices (devices).

  An example of a technique related to a noise filter used for noise suppression of an electronic device (apparatus) is described in Patent Document 1. This technique measures the attenuation characteristics of a noise filter, creates a database, and selects a noise filter suitable for each noise countermeasure target device.

JP-A-11-248775

  In the technique disclosed in Patent Document 1, one selected filter is mounted on an electronic apparatus (device). However, an electric signal cable having different characteristics may be connected to the electronic device (device) for the convenience of the user. Therefore, the filter may not be suitable, and noise countermeasures may fail.

  The objective of this invention is providing the electronic device, noise suppression system, and noise suppression method which solve the said problem.

An electronic device of the present invention includes an internal signal line connected to an internal circuit, and a signal generator switch for selecting either the signal generator,
A switch for SWR meter for selecting connection or non-connection of the SWR meter to the internal signal line;
A filter selection circuit that includes a plurality of filter circuits, and that selects one of the filter circuits that connects between the switch for SWR and an electric signal cable;
According to an instruction from the control device, a test signal from the signal generator is output to the electric signal cable via the signal generator switch, the SWR meter switch, the SWR meter, and the filter selection circuit. The signal generator switch and the SWR meter switch are controlled, and the filter circuit selected based on the measurement result of each SWR value for the plurality of filter circuits by the SWR meter is controlled to be used in operation. The internal circuit.

  According to the noise suppression method of the present invention, a test signal from a signal generator is passed through a signal generator switch, an internal signal line, an SWR meter switch, a filter selection circuit including a plurality of filter circuits, and an SWR meter. Thus, each SWR value for the filter circuit can be measured by the SWR meter, and the filter circuit of the electronic device selected based on the selection index including the SWR value is used during operation.

  The present invention has an effect that noise can be easily suppressed and reliability can be improved.

It is a block diagram which shows the structure of the 1st Embodiment of this invention. It is operation | movement explanatory drawing which shows operation | movement of the 1st Embodiment of this invention. It is a block diagram which shows the structure of the 2nd Embodiment of this invention. It is a block diagram which shows the structure of the switch for signal generators. It is a block diagram which shows the structure of the switch for SWR meters. It is a block diagram which shows the structure of a filter selection circuit. It is operation | movement explanatory drawing which shows operation | movement of the 2nd Embodiment of this invention. It is operation | movement explanatory drawing which shows operation | movement of the 2nd Embodiment of this invention. It is explanatory drawing which shows the calculation result in the control apparatus of the 2nd Embodiment of this invention. It is explanatory drawing which shows the calculation result in the control apparatus of the 3rd Embodiment of this invention.

  Next, a first embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing the configuration of the first embodiment. Referring to FIG. 1, an electronic device 100 (for example, a computer or a control device) according to the first embodiment includes an internal circuit 110, a signal generator switch 120, an SWR meter switch 130, a filter selection circuit 140, and a switch control line. 150 and an internal signal line 160. Here, SWR is Standing Wave Ratio.

  The internal circuit 110 includes a clock generator 111. The internal circuit 110 is connected to an external control device. The internal circuit 110 and the filter selection circuit 140 are connected by an internal signal line 160 via a signal generator switch 120 and an SWR meter switch 130. The internal circuit 110 controls the signal generator switch 120, the SWR meter switch 130, and the filter selection circuit 140 by the switch control line 150.

  The signal generator switch 120 is connected to an external signal generator. The SWR meter switch 130 is connected to an external SWR meter. The filter selection circuit 140 is connected to an electric signal cable.

  The signal generator switch 120 selects either the internal signal line 160 connected to the internal circuit 110 or an external signal generator according to the switch control line 150. The SWR meter switch 130 selects connection / disconnection of the external SWR meter to the internal signal line 160 according to the switch control line 150.

  The filter selection circuit 140 includes a plurality of filter circuits having different characteristics, and selects one filter circuit according to the switch control line 150.

  Next, the operation of the first embodiment will be described with reference to the drawings.

  In normal operation, the internal circuit 110 selects the signal generator switch 120 and the SWR meter switch 130 by the switch control line 150, and selects the internal signal line 160, respectively, so that it is disconnected from the SWR meter. To control. That is, in a normal operation, the internal circuit 110 and the filter selection circuit 140 are connected by the internal signal line 160. A signal from the internal circuit 110 passes through the internal signal line 160 and the filter selection circuit 140 and is output to the electric signal cable.

  Next, the operation of selecting a filter circuit for suppressing noise (radiation, conduction) from the electric signal cable will be described. FIG. 2 is an operation explanatory diagram illustrating an operation of the electronic device 100 according to the first embodiment. First, an external control device, a signal generator, an SWR meter, and an electric signal cable are connected to the electronic device 100 by hand or the like. Electrical signal cables having various characteristics can be connected.

  Referring to FIG. 2, the internal circuit 110 selects a signal generator for the signal generator switch 120 and the SWR meter switch 130 and connects to the SWR meter in accordance with an instruction from an external control device. Control is performed (step S1).

  Next, the internal circuit 110 performs control so that one filter circuit of the filter selection circuit 140 is selected by the switch control line 150 in accordance with an instruction from the external control device (step S2).

  Next, a test signal (traveling wave) having the fundamental frequency of the clock generator 111 and its harmonic number is output from the signal generator. Here, the harmonic number means a frequency that is 2, 3,..., N times the fundamental frequency. n is an integer of 1 or more and is set in advance.

  The electronic device 100 receives the test signal by the signal generator switch 120, and outputs the test signal to the electric signal cable via the internal signal line 160, the SWR meter switch 130, and the filter selection circuit 140 (step S3).

  The electronic device 100 outputs the traveling wave of each test signal and the reflected wave from the electric signal cable that has passed through the filter selection circuit 140 to the SWR meter via the SWR meter switch 130 (step S4).

  The SWR meter measures the traveling wave and reflected wave of each test signal and calculates each SWR value.

  Next, the internal circuit 110 performs control so that another filter circuit of the filter selection circuit 140 is selected by the switch control line 150 in accordance with an instruction from an external control device (step S2). And the process of step S2-step S4 is repeated sequentially with respect to all the filter circuits of the filter selection circuit 140. FIG.

  In this way, the SWR meter measures the traveling wave and reflected wave of each test signal for all the filter circuits of the filter selection circuit 140, and calculates each SWR value.

  Then, the external control device, the signal generator, the SWR meter, and the like are removed from the electronic device 100 by hand.

  The external control device receives each SWR value for all filter circuits of the filter selection circuit 140 from the SWR meter, and selects a filter circuit suitable for suppressing noise (radiation, conduction) from the electric signal cable. Perform the calculation.

  For example, the external control device calculates the sum of the SWR values for each test signal or the standard deviation of the SWR values for each filter circuit. Furthermore, the external control device uses, for example, one of the sum of the SWR values for each filter circuit, the reciprocal of the standard deviation of the SWR values, or a combination thereof as the selection index value. Then, the external control device, for example, selects the maximum one from all the selection index values, and specifies the corresponding filter circuit.

  Here, the calculation formula of the selection index value used for selecting the filter circuit is not limited to the above-described method. In other words, the selection index value used for selection of the filter circuit may be obtained by a calculation formula related to the SWR value.

  Next, the electronic device 100 stores information regarding the filter circuit (of the filter selection circuit 140) specified by the external control device, and performs normal operation using the specified filter circuit (step S5). ).

  When electrical signal cables having different characteristics are connected, it is possible to select a filter circuit for suppressing noise (radiation, conduction) from the electrical signal cable.

  Next, the effect of the first embodiment will be described.

  The electronic device 100 according to the first embodiment has a configuration including a signal generator switch 120, an SWR meter switch 130, and a filter selection circuit 140 including a plurality of filter circuits. That is, the electronic device 100 can receive a test signal from the outside, measure the SWR value for each filter circuit, and select a filter circuit suitable for suppressing noise (radiation, conduction) from the electric signal cable. .

  Therefore, the first embodiment has an effect that noise (radiation, conduction) can be easily suppressed and reliability can be improved.

  Next, a second embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 3 is a block diagram showing the configuration of the second embodiment. Referring to FIG. 3, the noise suppression system 800 according to the second embodiment includes an electronic device 100, a control device 200, a signal generator 300, an SWR meter 400, and an electric signal cable 500.

  The electronic device 100 is an example of the electronic device 100 according to the first embodiment, and includes a connector 171, a connector 172, a connector 173, and a connector 174. Further, the electronic device 100 can have various shapes such as a shelf type and a pizza box type.

  Further, the control device 200, the signal generator 300, the SWR meter 400, and the electric signal cable 500 each perform the operations described in the first embodiment. The internal circuit 110 outputs a control signal on the switch control line 150. In the following description, the switch control line 150 is a control signal on the switch control line 150.

  The connector 171 is used for connection between the internal circuit 110 and the control bus 600 (that is, the control device 200). The connector 172 is used for connection between the signal generator switch 120 and the signal generator 300. The connector 173 is used to connect the SWR meter switch 130 and the SWR meter 400. The connector 174 is used to connect the filter selection circuit 140 and the electric signal cable 500.

  Next, the internal circuit 110 will be described. Referring to FIG. 3, the internal circuit 110 includes, for example, a clock oscillator 111 and a clock oscillator 112. There is no limit to the number of clock generators. Clock signals from the clock generators 111 and 112 are frequency-divided or multiplied and used in the internal circuit 110.

  Next, the signal generator switch 120 will be described. FIG. 4 is a block diagram showing the configuration of the signal generator switch 120. Referring to FIG. 4, the signal generator switch 120 connects the internal circuit 110 and the SWR meter switch 130 or connects the signal generator 300 and the SWR meter switch 130 according to the switch control line 150. Select what to do.

  Next, the SWR meter switch 130 will be described. FIG. 5 is a block diagram showing the configuration of the switch 130 for the SWR meter. Referring to FIG. 5, the SWR meter switch 130 includes a first switch 131 and a second switch 132.

  The first switch 131 selects whether the signal generator switch 120 and the filter selection circuit 140 are directly connected by the internal signal line 160 (ON) or not connected (OFF) according to the switch control line 150. The second switch 132 selects whether the signal generator switch 120 and the filter selection circuit 140 are connected (ON) or not connected (OFF) via the SWR meter 400 according to the switch control line 150.

  The first switch 131 and the second switch 132 operate exclusively. That is, when the first switch 131 is on (off), the second switch 132 is off (on).

  Next, the filter selection circuit 140 will be described. FIG. 6 is a block diagram showing the configuration of the filter selection circuit 140. Referring to FIG. 6, the filter selection circuit 140 includes, for example, a filter circuit 141, a filter circuit 142, and a filter circuit 143 having different characteristics. There is no limit to the number of filter circuits.

  The filter selection circuit 140 includes a filter switch 14A. The filter switch 14 </ b> A selects any one of the filter circuits 141 to 143 according to the switch control line 150 and connects to the SWR meter switch 130 and the electric signal cable 500.

  Next, the operation of the second embodiment will be described with reference to the drawings.

  7 and 8 are operation explanatory diagrams showing the operation of the second embodiment. First, the control device 200 is connected to the electronic device 100 via the connector 171 and the control bus 600 by hand or the like. Furthermore, the signal generator 300, the SWR meter 400, and the electric signal cable 500 are connected to the electronic device 100 via connectors 172, 173, and 174, respectively.

  Referring to FIGS. 7 and 8, the control device 200 instructs the internal circuit 110 of the electronic device 100 to control the signal generator switch 120, the SWR meter switch 130, and the filter selection circuit 140. Output (step S11).

  The internal circuit 110 controls the signal generator switch 120 and the SWR meter switch 130 to select the signal generator 300 and connect to the SWR meter 400 according to an instruction from the control device 200. (Step S12).

  That is, in the internal circuit 110, the switch control line 150 is disconnected at the signal generator switch 120 between the internal circuit 110 and the SWR meter switch 130, and the signal generator 300 and the SWR meter switch 130 are connected. Value. Further, the internal circuit 110 disconnects the switch control line 150 directly between the signal generator switch 120 and the filter selection circuit 140, and the signal generator switch 120 and the filter selection circuit 140 pass through the SWR meter 400. Value to be connected.

  The signal generator switch 120 disconnects the internal circuit 110 and the SWR meter switch 130 according to the value of the switch control line 150, and connects the signal generator 300 and the SWR meter switch 130 (step S13).

  The SWR meter switch 130 turns off the first switch 131 according to the value of the switch control line 150 and disconnects the signal generator switch 120 and the filter selection circuit 140 directly. Further, the SWR meter switch 130 turns on the second switch 132 in accordance with the value of the switch control line 150, and connects the signal generator switch 120 and the filter selection circuit 140 via the SWR meter 400 (step S14).

  Next, in accordance with an instruction from the control device 200, the internal circuit 110 sets (controls) the switch control line 150 to a value selected by the filter circuit 141 in the filter selection circuit 140 (step S15).

  The filter selection circuit 140 selects the filter circuit 141 with the filter switch 14A according to the value of the switch control line 150, and the SWR meter switch 130 and the electric signal cable 500 are connected via the filter circuit 141. (Step S16).

  Next, the control device 200 outputs an instruction for generating a test signal having a frequency f1 (for example, 1 [Gz]) to the signal generator 300 (step S17, from here, FIG. 8). The signal generator 300 outputs a test signal (traveling wave) having a frequency f1 to the signal generator switch 120 in accordance with an instruction from the control device 200 (step S18).

  The electronic device 100 receives the test signal (frequency f1) from the signal generator 300. The electronic device 100 outputs a test signal, which is a traveling wave, to the electric signal line cable 500 via the signal generator switch 120, the SWR meter switch 130, the SWR meter 400, and the filter selection circuit 140 (filter circuit 141). (Step S19).

  When the electrical signal cable 500 receives the test signal (traveling wave), a reflected wave in the reverse direction is generated. The reflected wave from the electric signal cable 500 propagates in the order of the filter selection circuit 140 (filter circuit 141), the SWR meter switch 130, and the SWR meter 400 (step S20).

  The SWR meter 400 measures the traveling wave voltage V1 and the reflected wave voltage V2, and calculates the SWR value for the test signal (frequency f1) (step S21). For example, the SWR value is (V1 + V2) / (V1-V2).

  Next, the control device 200 acquires the SWR value for the filter circuit 141 and the test signal (frequency f1) from the SWR meter 400 (step S22).

  Next, the control device 200 outputs an instruction for generating a test signal having a frequency f2 (for example, 2 [Gz]) (step S17). Subsequently, an operation (step S18 to step S22) for the filter circuit 141 and the test signal (frequency f2) is executed. In this way, the operation (steps S17 to S22) for the test signals of all frequencies instructed by the control device 200 with respect to the filter circuit 141 is executed.

  In the control device 200, the frequency of the test signal is set in advance by hand or the like. For example, the frequency of the test signal is the fundamental frequency of the clock generators 111 and 112 of the internal circuit 110 and the frequency of their harmonics. Moreover, the structure containing the frequency (1/2, 1/3, ...) of the divided frequency is possible.

  For example, if the basic frequency f1 of the clock oscillator 111 is 1 [Gz], the frequency f1 = 1 [Gz], f2 = 2 [Gz], f3 = 3 [Gz],..., F10 = 10 [Gz]. Is set. When the frequency f11 of the clock oscillator 112 is 10 [Mz], the frequencies of f11 = 10 [Mz], f12 = 20 [Mz], f13 = 30 [Mz],..., F20 = 100 [Mz] are obtained. Is set.

  Next, the control device 200 outputs an instruction to select the filter circuit 142 of the filter selection circuit 140 to the internal circuit 110 (step S11). Subsequently, the operation (step S12 to step S22) for the filter circuit 142 is executed. In this way, the operations (steps S11 to S22) for all the filter circuits 141 to 143 are executed.

  Next, the control device 200 calculates the sum of the SWR values and the standard deviation for each of the filter circuits 141 to 143 (step S23). FIG. 9 is an explanatory diagram illustrating a calculation result in the control device 200 according to the second embodiment.

  Referring to FIG. 9, the sum ΣS1i of SWR values S101, S102,... Further, a sum ΣS2i of SWR values S201, S202,..., S220 and a standard deviation σ2 with respect to the frequencies f1 to f20 of the filter circuit 142 are calculated. In addition, the sum ΣS3i of the SWR values S301, S302,..., S320 and the standard deviation σ3 with respect to the frequencies f1 to f20 of the filter circuit 143 are calculated.

  Next, the control device 200 calculates selection index values (reciprocal of standard deviation of SWR value / sum of SWR values) for the filter circuits 141 to 143, respectively (step S24). That is, the control device 200 calculates (ΣS1i) / σ1 for the filter circuit 141, (ΣS2i) / σ2 for the filter circuit 142, and (ΣS3i) / σ3 for the filter circuit 143.

  Next, the control device 200 identifies the one (for example, the filter circuit 142) corresponding to the calculated maximum selection index value (for example, (ΣS2i) / σ2) from the filter circuits 141 to 143 (step S25). . Then, the control device 200 outputs filter specifying information (information indicating the specified filter circuit 142) to the internal circuit 110 (step S26).

  When receiving the filter specifying information, the internal circuit 110 stores the filter specifying information in a nonvolatile storage unit or the like (not shown) (step S27). Further, the internal circuit 110 controls the switch control line 150 so that the internal circuit 110 and the signal generator switch 120, the SWR meter switch 130, and the filter selection circuit 140 are connected.

  Then, the control device 200, the signal generator 300, the SWR meter 400, and the control bus 600 are removed from the electronic device 100 by hand or the like.

  Thereafter, the internal circuit 110 controls the filter selection circuit 140 based on the stored filter specifying information during normal operation. That is, thereafter, the electronic device 100 uses, for example, the filter circuit 142 indicated by the filter specifying information during normal operation (step S28).

  Next, the reason why (reciprocal of standard deviation of SWR value / sum of SWR value) is used as the selection index value will be described.

  The minimum value that can be taken by the SWR value is “1”, but this value is a state in which impedance matching is completely achieved, and the current of the target frequency flows out from the electronic device 100 to the electric signal cable 500. Means. That is, the greater the SWR value, the greater the reflection from the electric signal cable 500, and the current of the target frequency does not flow to the electric signal cable 500.

  Further, if the current flowing into the electric signal cable 500 is small, noise (radiation, conduction) from the electric signal cable 500 due to the frequency of the flowing current is reduced. Therefore, in order to reduce noise (radiation, conduction) from the electric signal cable 500, it is effective to select a filter circuit having a large SWR value of the frequency that causes noise.

  Further, since the noise can be suppressed more uniformly as the variation for each frequency is smaller, it is effective to use (the reciprocal of the standard deviation of the SWR value).

  Next, the effect of the second embodiment will be described.

  Since the second embodiment includes the electronic device 100 of the first embodiment, the second embodiment has the same effect as the first embodiment.

  Further, since the second embodiment uses (the reciprocal of the standard deviation of the SWR value / the sum of the SWR values) as the selection index value, the noise (radiation, conduction) from the electric signal cable 500 is efficiently obtained. It has the effect of being able to suppress.

  Next, a third embodiment will be described in detail with reference to the drawings.

  The hardware configuration of the third embodiment is the same as the hardware configuration of the second embodiment shown in FIG. The third embodiment differs from the second embodiment in the selection index value calculation formula. FIG. 10 is an explanatory diagram illustrating a calculation result in the control device 200 according to the third embodiment.

  Referring to FIG. 10, weights wi (w1 to w20) are defined for the frequencies f1 to f20, and the control device 200 calculates a weighted SWR value obtained by multiplying the weight and each SWR value. Then, the control device 200 calculates the sum Σ (wi · S1i) of the weighted SWR values for the filter circuit 141 and the standard deviation wσ1 of the weighted SWR values.

  Further, the control device 200 calculates the sum Σ (wi · S2i) of the weighted SWR values for the filter circuit 142 and the standard deviation wσ2 of the weighted SWR values. Further, the control device 200 calculates the sum Σ (wi · S3i) of the weighted SWR values for the filter circuit 143 and the standard deviation wσ3 of the weighted SWR values.

  Next, the control device 200 calculates selection index values {Σ (wi · S2i)} / wσ1, {Σ (wi · S2i)} / wσ2, and {Σ (wi · S3i)} / wσ3. Next, control device 200 identifies the one corresponding to the calculated maximum selection index value (for example, {Σ (Wi · S2i)} / wσ1) (for example, filter circuit 141) from filter circuits 141-143. . Thus, the filter circuit 141 is used in normal operation.

  The weight Wi is determined in consideration of the use of the clock signal in the internal circuit 110, and is set in advance in the control device 200 manually.

  For example, during normal operation, the frequency weight of the clock signal used to create a normal signal output from the internal circuit 110 to the electrical signal cable 500 via the internal signal line 160 is set to “0”, It is possible to set all frequency weights to “1”. In this way, it is possible to prevent a normal signal (not noise) that should originally be transmitted from becoming difficult to be transmitted to the electric signal cable 500.

  Next, the effect of the third embodiment will be described.

  Since the third embodiment uses the weight of each frequency as the selection index value, the third embodiment has an effect that more suitable filter circuits 141 to 143 can be selected compared to the second embodiment.

  A part or all of the above-described embodiment can be described as in the following supplementary notes, but is not limited thereto.

[Appendix 1]
An internal signal line connected to the internal circuit, and a signal generator switch for selecting one of the signal generators;
A switch for SWR meter for selecting connection or non-connection of the SWR meter to the internal signal line;
A filter selection circuit that includes a plurality of filter circuits, and that selects one of the filter circuits that connects between the switch for SWR and an electric signal cable;
According to an instruction from the control device, a test signal from the signal generator is output to the electric signal cable via the signal generator switch, the SWR meter switch, the SWR meter, and the filter selection circuit. The signal generator switch and the SWR meter switch are controlled, and the filter circuit selected based on the measurement result of each SWR value for the plurality of filter circuits by the SWR meter is controlled to be used in operation. Said internal circuit to
An electronic device comprising:

[Appendix 2]
The control device, the signal generator, the SWR meter, the electronic device according to appendix 1,
A noise suppression system comprising:

[Appendix 3]
The noise suppression system according to appendix 2, wherein the signal generator outputs a harmonic or a divided frequency of the internal circuit with respect to the frequency of the clock generator as the test signal.

[Appendix 4]
The SWR meter measures a traveling wave as the test signal and a reflected wave from the electric signal cable, and calculates an SWR value for each filter circuit and each test signal. 3. Noise suppression system.

[Appendix 5]
The control device calculates, for each filter circuit, the sum of the SWR values or the standard deviation of the SWR values for each test signal, and the sum of the SWR values, the standard deviation of the SWR values, or the One of the combinations of the sum of SWR values and the standard deviation of the SWR values is used as a selection index, one filter circuit is identified based on the selection index, and filter identification information indicating the identified filter circuit is stored in the internal Output to the circuit,
The noise suppression system according to appendix 4, wherein the internal circuit operates using the filter circuit indicated in the filter specifying information.

[Appendix 6]
The control device specifies (the reciprocal of the standard deviation of the SWR value) · (sum of the SWR values) as the selection index, specifies the filter circuit having the maximum selection index, and indicates the specified filter circuit The noise suppression system according to appendix 5, wherein the filter specifying information is output.

[Appendix 7]
The control circuit calculates a weighted SWR value obtained by multiplying a weight for each test signal, calculates a sum of the weighted SWR values and a standard deviation of the weighted SWR values for each filter circuit, and The selection index is a sum of weighted SWR values, a standard deviation of the weighted SWR values, or a combination of the sum of the weighted SWR values and the standard deviation of the weighted SWR values, and is based on the selection index. Identifying one of the filters, outputting filter identification information indicating the identified filter circuit to the internal circuit;
The noise suppression system according to appendix 4, wherein the internal circuit operates using the filter circuit indicated in the filter specifying information.

[Appendix 8]
The control device uses (the reciprocal of the standard deviation of the weighted SWR value) · (sum of the weighted SWR values) as the selection index, identifies the filter circuit having the maximum selection index, and identifies the filter circuit The noise suppression system according to appendix 7, wherein the filter specifying information indicating a filter circuit is output.

[Appendix 9]
The test signal from the signal generator is output to the electrical signal cable via the signal generator switch of the electronic device, the internal signal line, the switch for the SWR meter, the filter selection circuit including a plurality of filter circuits, and the SWR meter. A noise suppression method characterized in that each SWR value for the filter circuit can be measured by the SWR meter, and the filter circuit of the electronic device selected based on a selection index including the SWR value is used during operation.

[Appendix 10]
The noise suppression system according to appendix 9, wherein a harmonic or a sub-frequency with respect to the frequency of the clock generator in the electronic device is used as the test signal.

[Appendix 11]
The noise suppression system according to appendix 10, wherein a traveling wave as the test signal and a reflected wave from the electric signal cable are measured, and an SWR value for each of the filter circuits and the test signals is calculated. .

[Appendix 12]
For each filter circuit, the sum of the SWR values or the standard deviation of the SWR values for each test signal is calculated, and the sum of the SWR values, the standard deviation of the SWR values, or the sum of the SWR values One of the combinations with the standard deviation of the SWR value is used as a selection index, one filter circuit is identified based on the selection index, and filter identification information indicating the identified filter circuit is output to the internal circuit,
The noise suppression system according to appendix 11, wherein the electronic device is operated using the filter circuit indicated in the filter specifying information.

[Appendix 13]
(Reciprocal of standard deviation of the SWR value) · (sum of the SWR values) is used as the selection index, the filter circuit having the maximum selection index is specified, and the filter specifying information indicating the specified filter circuit is The noise suppression system according to appendix 12, wherein the noise suppression system is generated.

[Appendix 14]
A weighted SWR value obtained by multiplying a weight for each test signal is calculated, a sum of the weighted SWR values and a standard deviation of the weighted SWR values are calculated for each filter circuit, and a sum of the weighted SWR values is calculated. , A standard deviation of the weighted SWR values, or a combination of a sum of the weighted SWR values and a standard deviation of the weighted SWR values as a selection index, and one filter based on the selection index Identify and output filter identification information indicating the identified filter circuit to the internal circuit;
The noise suppression system according to appendix 11, wherein the electronic device is operated using the filter circuit indicated in the filter specifying information.

[Appendix 15]
The (reciprocal of the standard deviation of the weighted SWR value) · (sum of the weighted SWR values) is used as the selection index, the filter circuit having the maximum selection index is identified, and the identified filter circuit is indicated. The noise suppression system according to supplementary note 14, wherein the filter specifying information is generated.

DESCRIPTION OF SYMBOLS 100 Electronic device 110 Internal circuit 111 Clock generator 112 Clock generator 120 Signal generator switch 130 SWR meter switch 131 First switch 132 Second switch 140 Filter selection circuit 141 Filter circuit 142 Filter circuit 143 Filter circuit 14A Filter switch 150 switch Control line 160 Internal signal line 171 Connector 172 Connector 173 Connector 174 Connector 200 Control device 300 Signal generator 400 SWR meter 500 Electric signal cable 600 Control bus

Claims (9)

An internal signal line connected to the internal circuit, and a signal generator switch for selecting one of the signal generators;
A switch for SWR meter for selecting connection or non-connection of the SWR meter to the internal signal line;
A filter selection circuit that includes a plurality of filter circuits and selects one of the filter circuits that connects between the switch for the SWR meter and the electric signal cable;
According to an instruction from the control device, a test signal from the signal generator is output to the electric signal cable via the signal generator switch, the SWR meter switch, the SWR meter, and the filter selection circuit. The signal generator switch and the SWR meter switch are controlled, and the filter circuit selected based on the measurement result of each SWR value for the plurality of filter circuits by the SWR meter is controlled to be used in operation. Said internal circuit to
The signal generator outputs a harmonic or a divided frequency as the test signal with respect to the frequency of the clock generator of the internal circuit.
Electronics. The control device, the signal generator, the SWR meter, and the electronic device according to claim 1;
A noise suppression system comprising: The SWR meter measures a traveling wave that is the test signal and a reflected wave from the electric signal cable, and calculates an SWR value for each of the filter circuits and each of the test signals. Item 2. The noise suppression system according to Item 2 . The control device calculates, for each filter circuit, the sum of the SWR values or the standard deviation of the SWR values for each test signal, and the sum of the SWR values, the standard deviation of the SWR values, or the One of the combinations of the sum of SWR values and the standard deviation of the SWR values is used as a selection index, one filter circuit is identified based on the selection index, and filter identification information indicating the identified filter circuit is stored in the internal Output to the circuit,
The noise suppression system according to claim 3 , wherein the internal circuit operates using the filter circuit indicated in the filter specifying information. The control device specifies (the reciprocal of the standard deviation of the SWR value) · (sum of the SWR values) as the selection index, specifies the filter circuit having the maximum selection index, and indicates the specified filter circuit 5. The noise suppression system according to claim 4 , wherein the filter specifying information is output. The control device calculates a weighted SWR value obtained by multiplying a weight for each test signal, calculates a sum of the weighted SWR values and a standard deviation of the weighted SWR values for each filter circuit, and The selection index is a sum of weighted SWR values, a standard deviation of the weighted SWR values, or a combination of the sum of the weighted SWR values and the standard deviation of the weighted SWR values, and is based on the selection index. Specify one filter circuit , and output filter specifying information indicating the specified filter circuit to the internal circuit,
The noise suppression system according to claim 3, wherein the internal circuit operates using the filter circuit indicated in the filter specifying information.

The control device uses (the reciprocal of the standard deviation of the weighted SWR value) · (sum of the weighted SWR values) as the selection index, identifies the filter circuit having the maximum selection index, and identifies the filter circuit 7. The noise suppression system according to claim 6 , wherein the filter specifying information indicating a filter circuit is output. The test signal from the signal generator is output to the electrical signal cable via the signal generator switch of the electronic device, the internal signal line, the switch for the SWR meter, the filter selection circuit including a plurality of filter circuits, and the SWR meter. , Each SWR value for the filter circuit can be measured by the SWR meter, and the filter circuit of the electronic device selected based on a selection index including the SWR value is used during operation .
A noise suppression method using a harmonic or a divided frequency with respect to a frequency of a clock transmitter in the electronic device as the test signal . A noise suppression system using the noise suppression method according to claim 8 .