JP5715544B2 - Noise component processing method, noise component processing program, communication apparatus, communication system - Google Patents

Description

  The present invention relates to a method for processing a noise component in a communication signal and a communication apparatus.

  Control data and meter reading data are used in a power distribution automation system for separating accident sections when an accident occurs in a power distribution line for supplying power, and an automatic meter reading system for automating the meter usage of power usage. For transmission, a power line communication system, a wireless communication system, or the like is used. In a power line communication system, noise that is a communication failure is generated from a device connected to a distribution line, and thus an error may occur in communication data, which may impair communication reliability. Therefore, a noise component removal technique has been developed as one technique for reducing the influence of noise.

  As background art of this technical field, there is Patent Document 1 below. In the noise component removal technique described in Patent Document 1, a noise component is detected during a transmission suspension period of a fixed period, and the amplitude of the detected noise component is equal to or close to the amplitude at the frequency. By generating a cancel signal that is a continuous wave of the phase and adding it to the received signal, the noise component is removed.

JP 2009-21678 A

  In the technique described in Patent Document 1, a cancel signal is generated based on a noise component detected in the previous stage of the received signal. For this reason, determination regarding the periodicity and randomness of noise is not performed, and an erroneous cancel signal may be generated particularly when aperiodic random noise is included. Further, since the cancel signal is added to the reception signal before the analog / digital (A / D) conversion process, it is necessary to add the reception signal and the cancel signal at a highly accurate timing, and the noise component removal accuracy is improved. There is a problem that it tends to decrease. Furthermore, since a plurality of signal reception circuits and transmission circuits are provided for detecting a noise component and generating a cancel signal, there is a problem that the circuit scale increases and the size and cost of the apparatus increase.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide a technique for efficiently and accurately identifying periodic noise and non-periodic noise included in a communication signal.

  In the noise component processing method according to the present invention, the phase or amplitude of the noise component in the signal interval between the first no-signal interval and the second no-signal interval is calculated, and the first noise and signal interval in the first no-signal interval are calculated. Is used to determine whether the first noise is periodic noise or non-periodic noise using the phase or amplitude of the noise component and the second noise in the second no-signal section.

  According to the noise component processing method of the present invention, the reliability of communication can be improved by removing the noise component from the communication signal. In particular, the noise component can be accurately removed by distinguishing between periodic noise and non-periodic noise.

1 is a configuration diagram of a distribution automation system 1000 according to Embodiment 1. FIG. It is a figure which shows the structure of the communication apparatus 10a. It is a figure which shows the structure of the power supply device 23a. 2 is a diagram illustrating a configuration of a communication unit 21. FIG. 3 is a diagram illustrating a configuration of a transmission processing unit 104. FIG. It is a figure which shows the structure of the communication signal 150 which the transmission process part 104 produces | generates. 3 is a diagram illustrating a configuration of a reception processing unit 107. FIG. It is a figure which shows an example of the noise phase in a no-signal area. It is a figure which shows the example of a method in which the noise periodicity determination part 176 determines noise periodicity. It is a figure which shows the example of the pseudo noise pattern which the pseudo noise pattern production | generation part 177 produces | generates. It is a figure which shows the example of the method by which the noise component removal part 178 removes a noise component.

<Embodiment 1>
FIG. 1 is a configuration diagram of a power distribution automation system 1000 according to Embodiment 1 of the present invention. The distribution automation system 1000 is a system that controls a switch for dividing or connecting sections when an accident or the like occurs in a distribution line.

  The distribution substation 1 is supplied with high voltage power such as 22 kV via the high voltage distribution line 70, and is converted into a lower voltage such as 6.6 kV in the high voltage transformer 80. And electric power, such as 6.6 kV, is supplied to the intermediate voltage distribution lines 50a and 50b via the circuit breakers 90a, 90b and 90c.

  The circuit breakers 90a, 90b, 90c are used to shut off the power supply to the accident section for safety when an accident occurs in the high-voltage distribution line 70, the medium-voltage distribution lines 50a, 50b, and the like.

  The switch 20a and the communication device 10a are both connected to the medium voltage distribution line 50a. Similarly, the switches 20b, 20c, 20d, 20e, and 20f and the communication devices 10b, 10c, 10d, 10e, and 10f are connected to the medium voltage distribution line.

  The switch 20a has a function of separating an accident section when a ground fault or a short circuit accident occurs in the medium voltage distribution line 50a. For example, when an accident occurs between the switches 20a and 20b, an opening / closing process is performed so as to separate the sections.

  The low voltage transformer 40a has a function of converting medium voltage power such as 6.6 kV into low voltage power such as 100V or 200V. The electric power converted into the low-voltage power of 100V or 200V is supplied to the low-voltage consumer 30a via the low-voltage distribution line 60a, and is consumed in the low-voltage consumer 30a. Similarly, the low-voltage transformer 40b converts medium-voltage power such as 6.6 kV into low-voltage power such as 100 V or 200 V and supplies the low-voltage consumers 30b and 30c via the low-voltage distribution line 60b.

  The switch 20f is normally in an open state, and the medium voltage distribution lines 50a and 50b are not connected. When an accident occurs in one distribution line and it is necessary to supply power from the other distribution line, the switch 20f is closed and the medium-voltage distribution lines 50a and 50b are connected.

  The communication devices 10a, 10b, 10c, 10d, 10e, and 10f are the communication device 10g or 10a, 10b, 10c, 10d, 10e, and 10f installed in the distribution substation 1 and the medium-voltage distribution line 50a. Alternatively, they are connected by 50b and communicate with each other by superimposing a communication signal on the medium-voltage distribution line 50a or 50b. The communication devices 10a, 10b, 10c, 10d, 10e, and 10f collect the distribution line voltage and current values by the sensors built in the switches 20a, 20b, 20c, 20d, 20e, and 20f, and send them to the communication device 10g. To transmit.

  The communication device 10g superimposes a control signal output from the control device 11 on the medium-voltage distribution line 50a or 50b in order to change the power supply path in the event of an accident or the like, so that the communication devices 10a, 10b, 10c, 10d, 10e and 10f. The communication devices 10a, 10b, 10c, 10d, 10e, and 10f control the switches 20a, 20b, 20c, 20d, 20e, and 20f according to this control signal.

  FIG. 2 is a diagram illustrating a configuration of the communication device 10a. The communication devices 10b, 10c, 10d, 10e, 10f, and 10g have the same configuration. The communication device 10a includes a communication unit 21, a switch control unit 22, power supply devices 23a and 23b, a power supply line 24, and communication lines 25, 26, 27a, and 27b.

  The communication unit 21 has a function of generating a communication signal for performing communication with another communication device. The power supply devices 23 a and 23 b convert 6.6 kV medium voltage power supplied from the distribution line 50 a into low voltage power such as 100 V and superimpose it on the power supply line 24. This power is power for operating the communication device 10a. The communication signal generated by the communication unit 21 is superimposed on the power supply line 24 and is superimposed on the distribution line 50a via the power supply devices 23a and 23b. In the present embodiment, the power supply devices 23a and 23b are shown separately for the sake of simplicity, but may be configured as a single unit.

  The communication unit 21 is connected to the switch control unit 22 via the communication line 25, and transmits a signal for controlling the switch 20a. The switch control unit 22 controls the switch 20a according to the control signal. In addition, the switch control unit 22 collects values such as voltage and current collected by the switch 20 a via the communication line 26.

  The communication unit 21 can switch a switch 28 (described later in FIG. 3) included in the power supply device 23a or 23b via the communication lines 27a and 27b. Since each of the power supply devices 23a and 23b has a function of converting medium-voltage power into low-voltage power and providing the same to the communication device 10a, the switch 28 to be operated of the power supply devices 23a and 23b is turned on, and the other is Turn off. For example, when the medium-voltage distribution line 50a connected to the power supply device 23a fails, the switch 28 provided in the power supply device 23a is turned off, and the switch 28 provided in the power supply device 23b is turned on.

  FIG. 3 is a diagram illustrating a configuration of the power supply device 23a. The power supply device 23b has a similar configuration. The medium-voltage power of 6.6 kV supplied from the distribution line 50 a is converted into low-voltage power such as 100 V by a circuit composed of a transformer and a capacitor and is superimposed on the power supply line 24. A communication signal transmitted between the communication devices 10 is also transmitted via a transformer and a capacitor. The switch 28 turns on / off the connection of the power supply line 24 in accordance with a control signal transmitted via the communication line 27a. By switching ON / OFF of the switch 28, one connection can be disconnected so that a communication signal is not transmitted twice through both the power supply devices 23a and 23b.

  FIG. 4 is a diagram illustrating a configuration of the communication unit 21. The communication unit 21 includes a coupler 111, band pass filters (BP filters) 101a and 101b, a transmission amplifier 102, a reception amplifier 109, a digital / analog converter (D / A) 103, and an analog / digital converter (A / D). 108, a transmission processing unit 104, a reception processing unit 107, an access controller 105, a protocol conversion unit 106, and a power supply unit 110. A communication line 25 connects between the communication unit 21 and the switch control unit 22. Or you may comprise the communication part 21 and the switch control part 22 as integral.

  The protocol conversion unit 106 receives data to be transmitted via the power supply line 24 via the communication line 25 and converts it into communication data in a predetermined format handled by the communication unit 21. Upon receiving communication data from the protocol converter 106, the access controller 105 outputs this data to the transmission processing unit 104 and generates a communication signal. The D / A 103 converts the communication signal into an analog signal. The transmission amplifier 102 amplifies the analog signal. The BP filter 101a cuts unnecessary high-frequency components included in the analog communication signal, and then outputs them to the power supply line 24 via the coupler 111.

  The BP filter 101 b suppresses signals other than the communication band among the communication signals transmitted to the communication unit 21 via the power supply line 24, and outputs the communication band signal to the reception amplifier 109. The reception amplifier 109 amplifies the reception signal. The A / D 108 converts the amplified received signal into a digital signal. The reception processing unit 107 acquires a digital signal from the A / D 108, demodulates the data, and outputs it to the access controller 105. The access controller 105 converts the demodulated data into communication data of a predetermined format and outputs it to the protocol conversion unit 106. The protocol conversion unit 106 converts the communication data so that an interface with the switch control unit 22 can be obtained and outputs the communication data to the switch control unit 22.

  When controlling the switch 28 of the power supply device 23a, the access controller 105 transmits control data via the communication line 27a. When controlling the switch of the power supply device 23b, control data is transmitted through the communication line 27b. The power supply line 24 is also connected to the power supply unit 110, and the power supply unit 110 receives power used by the communication unit 21 via the power supply line 24, and converts a voltage of 100V to DC5V or the like as necessary. .

  FIG. 5 is a diagram illustrating a configuration of the transmission processing unit 104. It is assumed that the transmission processing unit 104 uses an Orthogonal Frequency Division Multiplexing (OFDM) system as a communication system. However, the communication method used in the present invention is not necessarily limited to the OFDM method. For example, the present invention can be applied to a BPSK communication system that performs single carrier modulation.

  The transmission processing unit 104 includes a serial / parallel (S / P) conversion unit 140, a modulation unit 141, an inverse fast Fourier transform (IFFT) processing unit 142, a guard interval (GI) addition unit 143, a no-signal section generation unit 144, a synchronization A signal generation unit 145 is provided.

  The S / P converter 140 converts data input from the access controller 105 from serial data to parallel data. In this process, transmission data configured as serial data for digital signal processing is parallelized for analog transmission. Modulation section 141 allocates transmission data to a plurality of carriers (carrier waves) and modulates the carriers. The IFFT processing unit 142 performs a reverse fast Fourier transform process on a plurality of carriers, and generates a time waveform of a communication signal for each symbol. Here, the symbol is a data unit for processing a communication signal when transmitting and receiving communication data. The GI adding unit 143 copies (duplicates) a part of the communication signal and adds it as a GI to the communication signal. GI is added for the purpose of mitigating the influence on a communication signal when a delayed wave is generated due to multipath fading or the like. The no-signal section generation unit 144 provides a no-signal section that does not include a communication signal between symbols of the communication signal. An example of the no-signal section will be described with reference to FIG. The synchronization signal generation unit 145 adds a synchronization signal to the communication signal. The synchronization signal is for the communication device 10 on the receiving side to detect a communication signal and specify a symbol cut-out position for performing reception processing.

  FIG. 6 is a diagram illustrating a configuration of the communication signal 150 generated by the transmission processing unit 104. The communication signal 150 includes a synchronization signal 151, symbols 152a, 152b, 152c, 152d, 152e, and 152f and no-signal sections 153a and 153b. In the first embodiment, in order to simplify the description, a configuration example of one synchronization signal, six symbols, and two no-signal sections will be described. However, the number and configuration of the synchronization signals, symbols, and no-signal sections are changed. It doesn't matter.

  Between the symbols 152a, 152b, 152c, 152d, 152e, and 152f, no-signal sections 153a and 153b are provided. If the time intervals of the no-signal sections 153a and 153b are the same as those of the symbols 152a, 152b, 152c, 152d, 152e, and 152f, the transmission processing and the reception processing can be simplified, but the time intervals are not necessarily the same. Not necessarily.

  FIG. 7 is a diagram illustrating a configuration of the reception processing unit 107. The reception processing unit 107 includes a synchronization unit 170, a guard interval (GI) removal unit 171, a fast Fourier transform (FFT) processing unit 172, a memory unit 173, a no-signal interval determination unit 174, a noise amplitude / phase calculation unit 175, a noise period. A determination unit 176, a pseudo noise pattern generation unit 177, a noise component removal unit 178, a demodulation unit 179, and a parallel / serial (P / S) conversion unit 180.

  Synchronizing section 170 specifies a symbol cutout position, which is a processing unit of a communication signal input from A / D converter 108, using a synchronization signal. The GI removal unit 171 removes a guard interval (GI) that is normally added when the OFDM method is used as a communication method. The FFT processing unit 172 performs fast Fourier transform (FFT) processing, and generates digital data obtained by dividing the communication signal for each frequency carrier. The memory unit 173 is a storage device that stores the FFT-processed communication signal as digital data for each frequency carrier. Note that the amplitude and phase components of noise for each frequency can be extracted by performing the FFT processing in the same manner in the no-signal section.

  The no-signal section determination unit 174 identifies a no-signal section that does not include a communication signal among communication signals (digital data) stored in the memory unit 173, and determines a noise component superimposed on the no-signal section. Extract. As a method for specifying the no-signal section, for example, the no-signal section may be extracted at a timing determined between the communication devices 10 that transmit and receive in advance, or the amplitude of the communication signal is equal to or less than a predetermined threshold. When it becomes, you may determine with it being a no-signal area. Other suitable techniques may be used. In the first embodiment, it is assumed that the timing of the no-signal section is determined between the communication devices 10 in advance.

  The noise amplitude / phase calculation unit 175 calculates the amplitude and phase of the noise component in the next no-signal interval using the amplitude and phase of the noise component included in the no-signal interval extracted by the no-signal interval determination unit 174. A specific calculation method will be described later with reference to FIG.

  The noise periodicity determination unit 176 determines whether the noise component is periodic noise or non-periodic noise based on the amplitude or phase of the noise component calculated by the noise amplitude / phase calculation unit 175. A specific determination method will be described later with reference to FIG.

  The pseudo noise pattern generation unit 177 generates a pseudo noise pattern based on the determination result by the noise periodicity determination unit 176. An example of the pseudo noise pattern will be described later with reference to FIG.

  The noise component removing unit 178 removes a noise component based on the pseudo noise pattern generated by the pseudo noise pattern generating unit 177 and the carrier amplitude and phase data of the symbol stored in the memory unit 173. A specific removal method will be described later with reference to FIG.

  The demodulator 179 demodulates the carrier data for each symbol from which the noise component has been removed. The parallel / serial (P / S) conversion unit 180 converts the parallel data into serial data and outputs the serial data to the access controller 105. In this process, parallel data that has been parallelized for analog transmission is serialized for digital processing.

  FIG. 8 is a diagram illustrating an example of a noise phase in a no-signal section. As shown in the noise phase (A), the noise component detected in the no-signal section 153a has a different phase Φ for each of the frequencies f1, f2, f3, and f4. Similarly, the noise component detected in the no-signal section 153b has a phase Φ different from the noise phase (A) for each of the frequencies f1, f2, f3, and f4, as shown in the noise phase (B). When the noise signal detected in the no-signal section 153a and the noise signal detected in the no-signal section 153b are continuous, each phase in the noise phase (A) is advanced by an amount corresponding to the signal time T. A noise phase (B) should be obtained.

  The noise amplitude / phase calculation unit 175 calculates the amplitude and phase of the noise component in the no-signal section 153b for each frequency of the noise component using the amplitude and phase of the noise component extracted in the no-signal section 153a. Specifically, assuming that the carrier frequency of the communication signal is f and the signal time between the symbols 152c to 152d is T, the amount of change ΔΦ in the noise phase between the no-signal sections 153a to 153b is expressed by the following equation (1). Can be calculated.

ΔΦ = 2πf · T (1)
If the noise phase in the no-signal section 153a is Φ1, the phase Φ2 in the no-signal section 153b can be calculated by the following equation (2).

Φ2 = Φ1 + ΔΦ (2)
Since the phase has periodicity every 2π, if the phase obtained by calculation does not fall within the range of 0 to 2π, Φ2 ± 2πn (n is an integer) is calculated for 0 ≦ φ1 ≦ 2π. Thus, the value can be converted into a value in the range of 0 ≦ φ2 ≦ 2π.

  Although the phase of the noise component has been described above, since the initial power value of the noise component for each frequency can be obtained in the FFT processing, the amplitude change amount of the noise component is also calculated from the initial power value and the phase change amount ΔΦ. be able to.

  FIG. 9 is a diagram illustrating a method example in which the noise periodicity determination unit 176 determines noise periodicity. FIG. 9A shows an example where the noise is periodic noise, and FIG. 9B shows an example where the noise is non-periodic noise.

  In FIG. 9A, the noise periodicity determination unit 176 calculates a noise calculated value 155 corresponding to the noise component in the period between the symbols 152c and 152d based on the noise measurement value 154a extracted in the no-signal section 153a. Calculate Next, the noise periodicity determination unit 176 compares the noise measurement value 154b extracted in the no-signal section 153b with the noise calculation value 155, and determines whether or not the phases are continuous. Specifically, for example, if the difference between the signal values at the boundary between the noise measurement value 154b and the noise calculation value 155 is within a predetermined range, it can be considered that the phases are continuous. When the phases are continuous, the noise periodicity determination unit 176 determines that periodic noise is superimposed between the no-signal sections 153a and 153b.

  In FIG. 9B, since the phase is discontinuous at the boundary between the noise measurement value 154c and the noise calculation value 155, the noise periodicity determination unit 176 has a non-periodicity between the no-signal intervals 153a and 153b. It is determined that (random) noise is superimposed.

  When determining the continuity of the noise component, only the noise phase may be used, only the amplitude may be used, or the phase and the amplitude may be used in combination. For example, when only the phase is used, it may be determined whether or not the noise measurement value 154b is within a predetermined range on the time axis at the boundary between the noise measurement value 154b and the noise calculation value 155. When only the amplitude is used, the determination may be made similarly on the signal power axis. When both are used together, for example, the determination may be made based on whether or not the plane distance is within a predetermined range.

  FIG. 10 is a diagram illustrating an example of a pseudo noise pattern generated by the pseudo noise pattern generation unit 177. FIG. 10A shows the power of the pseudo noise pattern for each frequency. FIG. 10B shows an example of pseudo noise at the frequency f1.

  In FIG. 10A, since the noise of the frequencies f1, f3, and f4 is determined to be periodic noise, pseudo noise is generated, whereas the noise of the frequency f2 is determined to be non-periodic noise. Noise is not generated.

  In FIG. 10B, when the pseudo noise 156a is expressed on the constellation of the in-phase component I and the quadrature component Q, the length from the origin to the pseudo noise 156a is set as the pseudo noise amplitude 157, and the pseudo noise 156a from the in-phase component I axis. Can be expressed as a pseudo noise phase 158.

  FIG. 11 is a diagram illustrating an example of a method by which the noise component removing unit 178 removes noise components. When the carrier of the frequency f1 in the symbol 152c is shown on the axes of the in-phase component I and the quadrature component Q, it is assumed that the carrier 160 before correction is obtained. By adding the noise vector 159b obtained by inverting the phase of the noise vector 159a indicating the pseudo noise 156a to the carrier 160 before correction, the carrier 161 after correction can be obtained. Similarly, noise components can be removed from the other frequencies f3 and f4.

  For the carrier of frequency f2 that did not generate pseudo noise, it is not necessary to remove the noise component, and if the non-periodic noise can be accurately identified, the noise component may be positively removed. . In general, it is difficult to accurately identify non-periodic noise, so it is desirable that the non-periodic noise component should not be positively removed on the assumption that it will naturally disappear over time.

<Embodiment 1: Summary>
As described above, in the communication system 1000 according to the first embodiment, the communication apparatus 10 calculates the phase or amplitude of the noise component in the signal section, and whether the noise component in the plurality of no-signal sections is periodic noise. Is determined using the phase or amplitude of the calculated noise component. Thereby, periodic noise and aperiodic noise can be distinguished and a noise component can be removed appropriately. In particular, it is preferable to use the communication system 1000 according to the first embodiment in a communication system in which an error is likely to occur in communication data due to noise, for example, a power line communication system.

  Further, in the communication system 1000 according to the first embodiment, the communication device 10 can operate so as to remove only the noise component determined as periodic noise and not remove the noise component determined as non-periodic noise. . As a result, only the noise component can be accurately identified and removed, so that the noise processing can be performed while suppressing the influence on the signal quality.

  Further, in the communication system 1000 according to the first embodiment, the communication device 10 can remove the noise component with high accuracy because the communication device 10 removes the noise component for each carrier in the frequency domain.

  Further, in the communication system 1000 according to the first embodiment, the communication apparatus 10 performs the process of removing the noise component in the digital process after the analog / digital (A / D) conversion process. Specifically, noise processing is performed on the data stored in the memory unit 173 as digital data as a result of the Fourier transform performed by the FFT processing unit 172. Therefore, the noise removal process can be implemented with a simple process. Furthermore, since cancellation processing is executed in digital processing, it is not necessary to provide a plurality of transmission circuits and reception circuits of the communication device, and the size and cost of the communication device can be reduced.

  In the communication system 1000 according to the first embodiment, the communication device 10 performs noise removal processing on the communication signal data once stored in the memory 173. As a result, it is not always necessary to perform the noise removal processing in real time, and it is possible to suppress the calculation capability necessary for the noise processing.

<Embodiment 2>
The present invention is not limited to the embodiments described above, and includes various modifications. For example, the above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to one having all the configurations described. A part of the configuration of an embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of an embodiment. Further, with respect to a part of the configuration of each embodiment, another configuration can be added, deleted, or replaced.

  For example, in the first embodiment, the configuration in which the communication signal is superimposed on the power line has been described as an example of the communication system 1000. The application target of the present invention is not limited to this, and the present invention can also be applied to a communication system that adopts other forms. A configuration in which a communication line for data communication is separately provided instead of superimposing a communication signal on a power line, a configuration in which data communication is performed by wireless communication, and the like are considered as examples.

  Each of the above-described configurations, functions, processing units, processing means, and the like may be realized by hardware by designing a part or all of them with, for example, an integrated circuit. Each of the above-described configurations, functions, and the like may be realized by software by interpreting and executing a program that realizes each function by the processor. Information such as programs, tables, and files for realizing each function can be stored in a memory, a hard disk, a recording device such as an SSD (Solid State Drive), or a recording medium such as an IC card, an SD card, or a DVD. For example, it is considered that at least one of the transmission processing unit 104, the reception processing unit 107, the access controller 105, and the protocol conversion unit 106 is implemented as an arithmetic circuit on a programmable arithmetic device such as an FPGA (Field Programmable Gate Array). It is done.

  Further, the control lines and information lines indicate what is considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. Actually, it may be considered that almost all the components are connected to each other.

  In addition, the order of the processes performed by each of the functional units described above can be interchanged or executed in parallel without departing from the spirit of the present invention. For example, the process of acquiring the phase and amplitude of the noise component in the no-signal section 153b may be executed either before or after the process of calculating the phase and amplitude of the noise component in the signal sections 152c to 152d, or these are executed in parallel. May be.

1: Distribution substation 10a, 10b, 10c, 10d, 10e, 10f, 10g: Communication device 11: Control device 20a, 20b, 20c, 20d, 20e, 20f: Switch 21: Communication unit 22: Switch control unit 23a, 23b: Power supply device 24: Power supply line 25: Communication line 26: Communication line 27a, 27b: Communication line 28: Switches 30a, 30b, 30c: Low voltage consumer 40a, 40b: Low voltage transformer 50a, 50b: Medium Pressure distribution line 60a, 60b: Low voltage distribution line 70: High voltage distribution line 80: High voltage transformers 90a, 90b, 90c: Circuit breakers 101a, 101b: Band pass (BP) filter 102: Transmission amplifier 103: Digital / analog (D / A) Converter 104: Transmission processing unit 105: Access controller 106: Protocol conversion unit 107: Reception processing unit 108: Analog Digital (A / D) converter 109: Reception amplifier 110: Power supply unit 111: Coupler 140: Serial / parallel (S / P) conversion unit 141: Modulation unit 142: Inverse fast Fourier transform (IFFT) processing unit 143: Guard Interval (GI) adding section 144: No signal section generation section 145: Synchronization signal generation section 150: Communication signal 151: Synchronization signals 152a, 152b, 152c, 152d, 152e, 152f: Symbols 153a, 153b: No signal sections 154a, 154b 154c: measured noise value 155: calculated noise value 156a, 156b, 156c: pseudo noise 157: pseudo noise amplitude 158: pseudo noise phase 159a, 159b: noise vector 160: pre-correction carrier 161: post-correction carrier 170: synchronization unit 171 : Guard interval (GI) removal unit 72: Fast Fourier transform (FFT) processing unit 173: Memory unit 174: No signal section determination unit 175: Noise amplitude / phase calculation unit 176: Noise periodicity determination unit 177: Pseudo noise pattern generation unit 178: Noise component removal unit 179 : Demodulator 180: Parallel / serial (P / S) converter

Claims (17)

A method for processing a noise component included in a communication signal,
Extracting a first noise component included in a first no-signal section in the communication signal;
Calculating at least one of a phase or an amplitude of the first noise component;
Extracting a second noise component included in a second no-signal section in the communication signal;
Calculating the phase or amplitude of the first noise component in a signal interval between the first no-signal interval and the second no-signal interval using the calculated phase or amplitude of the first noise component;
Using the first noise component, the calculated phase or amplitude of the first noise component in the signal interval, and the second noise component, it is determined whether the first noise component is periodic noise or non-periodic noise. A periodicity determining step for determining;
A noise component processing method characterized by comprising: In the periodicity determining step,
Using the calculated phase or amplitude of the first noise component in the signal interval to complement the phase or amplitude of the first noise component in the signal interval;
As a result of the complementation, when the first noise component, the complemented first noise component in the signal interval, and the second noise component are continuous, it is determined that the first noise component is periodic noise. The noise component processing method according to claim 1, wherein when it is not continuous, it is determined as non-periodic noise. The noise component processing method according to claim 1, further comprising: a noise removal step of removing a noise component determined to be periodic noise at least in the periodicity determination step from the communication signal. The noise component processing method according to claim 3, wherein in the noise removal step, the noise component determined to be non-periodic noise in the periodicity determination step is not removed. A storage step of converting the communication signal into digital data and storing it in a storage device;
In the step of extracting the first noise component and the step of extracting the second noise component, the first noise component and the second noise component are obtained from the communication signal stored as digital data in the storage device. The noise component processing method according to any one of claims 1 to 4, wherein each of the noise component processing methods is extracted. Comprising Fourier transforming the communication signal;
The noise component processing method according to claim 5, wherein in the storing step, digital data of the communication signal obtained by the Fourier transform is stored in the storage device.   A noise component processing program that causes an arithmetic device to execute the noise component processing method according to claim 1. A no-signal section determination unit that identifies a no-signal section in a communication signal and extracts a noise component included in the no-signal section;
An amplitude phase calculation unit for calculating at least one of the phase and the amplitude of the noise component;
A periodicity determination unit that determines whether the noise component is periodic noise or non-periodic noise using the calculated phase or amplitude of the noise component;
With
The no-signal section determination unit
Extracting a first noise component included in a first no-signal section in the communication signal and a second noise component included in a second no-signal section in the communication signal;
The amplitude phase calculation unit is
Calculating the phase or amplitude of the first noise component, and using the calculated phase or amplitude of the first noise component, the first noise component in the signal interval between the first no-signal interval and the second no-signal interval; Calculate the phase or amplitude of one noise component,
The periodicity determination unit includes:
Using the first noise component, the calculated phase or amplitude of the first noise component in the signal interval, and the second noise component, it is determined whether the first noise component is periodic noise or non-periodic noise. A communication device characterized by determining. The periodicity determination unit includes:
Using the calculated phase or amplitude of the first noise component in the signal interval to complement the phase or amplitude of the first noise component in the signal interval;
As a result of the complementation, when the first noise component, the complemented first noise component in the signal interval, and the second noise component are continuous, it is determined that the first noise component is periodic noise. The communication device according to claim 8, wherein when it is not continuous, it is determined as non-periodic noise. The communication apparatus according to claim 8 or 9, further comprising: a noise removing unit that removes at least the noise component determined by the periodicity determining unit as periodic noise from the communication signal. The communication device according to claim 10, wherein the noise removing unit does not remove a noise component determined by the periodicity determining unit as non-periodic noise. A Fourier transform unit for Fourier transforming the communication signal;
A storage device for storing digital data of the communication signal obtained by the Fourier transform;
With
The no-signal section determination unit
The communication device according to any one of claims 8 to 11, wherein the first noise component and the second noise component are respectively extracted from the communication signal stored as digital data in the storage device. . The said no signal area determination part, the said amplitude phase calculation part, and the said periodicity determination part are comprised as an arithmetic circuit on a programmable arithmetic device. The one of Claims 8-12 characterized by the above-mentioned. Communication device.   A communication system comprising a plurality of communication devices according to claim 8. The communication system according to claim 14, wherein at least one of the plurality of communication apparatuses includes a transmission processing unit that generates and transmits a communication signal having a no-signal section. The communication system according to claim 14 or 15, wherein the plurality of communication devices use a distribution line as a communication line. The communication system according to any one of claims 14 to 16, wherein the communication device transmits and receives control data for controlling an operation of a switch in a power network.

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