CN114830546A

CN114830546A - Signal transceiving circuit and method for power line communication

Info

Publication number: CN114830546A
Application number: CN201980103103.1A
Authority: CN
Inventors: 潘稻; 林泽锋; 钟威; 李亚奇; 孔令晓
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2019-12-30
Filing date: 2019-12-30
Publication date: 2022-07-29
Anticipated expiration: 2039-12-30
Also published as: CN114830546B; WO2021134379A1

Abstract

The application discloses signal receiving and transmitting circuit and method of power line communication, the circuit includes differential mode coupling circuit, common mode coupling circuit and noise processing circuit, the differential mode coupling circuit and the common mode coupling circuit are respectively connected with power line, the noise processing circuit is connected with the differential mode coupling circuit and the common mode coupling circuit, the power line includes at least one of the following: the differential mode coupling circuit is used for coupling and receiving differential mode signals on a power line; the common mode coupling circuit is used for coupling and receiving a common mode signal on a power line; the noise processing circuit is used for processing the common mode signal and the differential mode signal so as to eliminate noise in the differential mode signal. A common mode coupling circuit is introduced to obtain a common mode signal on a power line, and a noise processing circuit is used for processing the received differential mode signal and the received common mode signal to eliminate noise, so that the performance of power line communication is improved.

Description

Signal transceiving circuit and method for power line communication

Technical Field

The present disclosure relates to the field of communications technologies, and in particular, to a signal transceiver circuit and a signal transceiver method for power line communications.

Background

The Power Line Communication (PLC) technology is a communication method for transmitting data and media signals using a power line.

Noise in power line communication mainly originates from electric appliances in a power line network, and load impedance of various electric appliances added to the power line network changes in real time, and noise interference also changes in real time. Electrical noise in power line communication generally appears as various forms of impulse noise, and the amplitude of the impulse is large, deteriorating the performance of power line communication. It is now common to utilize the periodic nature of the electrical noise to communicate over different time periods using the channel carrying capability of that time period. However, the noise of the electrical appliance is not improved, and the communication is performed only under the existing noise condition by matching the carrying capacity of the channel, so that the performance of the power line communication is poor.

Disclosure of Invention

The embodiment of the application provides a signal transceiving circuit and a signal transceiving method for power line communication, wherein a common mode coupling circuit is introduced to obtain a common mode signal on a power line, and a noise processing circuit is used for processing a received differential mode signal and the received common mode signal to eliminate noise, so that the performance of the power line communication is improved.

In a first aspect, an embodiment of the present application provides a signal transceiving circuit for power line communication, where the circuit includes a differential mode coupling circuit, a common mode coupling circuit, and a noise processing circuit, where the differential mode coupling circuit and the common mode coupling circuit are respectively connected to a power line, the noise processing circuit is connected to the differential mode coupling circuit and the common mode coupling circuit, and the power line includes at least one of: the differential mode coupling circuit is used for coupling and receiving differential mode signals on the power line; the common mode coupling circuit is used for coupling and receiving a common mode signal on the power line; the noise processing circuit is used for processing the common mode signal and the differential mode signal so as to eliminate noise in the differential mode signal.

In the circuit, the common mode coupling circuit is introduced to obtain the common mode signal on the power line, and because the noise in the differential mode signal obtained by the differential mode coupling circuit has correlation with the noise in the common mode signal, the noise processing circuit can process the differential mode signal and the common mode signal to eliminate the noise in the received signal, thereby improving the performance of power line communication.

With reference to the first aspect, in one possible implementation manner of the first aspect, the differential mode coupling circuit includes at least one coupling transformer and at least one transceiver circuit, each coupling transformer of the at least one coupling transformer is connected to at least two lines of the power line, and each coupling transformer of the at least one coupling transformer is coupled to one transceiver circuit of the at least one transceiver circuit, wherein each coupling transformer of the at least one coupling transformer is configured to couple a differential mode signal received from at least two lines of the power line to one transceiver circuit of the at least one transceiver circuit; each of the at least one transceiver circuit for receiving the differential mode signal that the each coupling transformer is coupled to.

With reference to the first aspect, in a possible implementation manner of the first aspect, the common mode coupling circuit includes a common mode transformer and a common mode signal receiving circuit, the common mode transformer is connected to the live wire, the neutral wire and the ground wire, and the common mode transformer is coupled to the common mode signal receiving circuit, wherein the common mode transformer is configured to couple a common mode signal received from the live wire, the neutral wire and the ground wire to the common mode signal receiving circuit; the common mode signal receiving circuit is used for receiving the common mode signal which is coupled to the common mode signal receiving circuit by the common mode transformer.

With reference to the first aspect, in one possible implementation manner of the first aspect, the differential mode coupling circuit includes a first coupling transformer, a first transceiving circuit, a second coupling transformer, and a second transceiving circuit, the first coupling transformer is connected with two lines of the power line, the first coupling transformer is coupled to the first transceiving circuit, the second coupling transformer is connected with two lines of the power line, the second coupling transformer is coupled to the second transceiving circuit, two lines of the power lines are two lines of a live line, a zero line and a ground line, two lines of the power lines connected with the first coupling transformer are different from two lines of the power lines connected with the second coupling transformer, the first coupling transformer is used for coupling first differential mode signals received from two lines in the power line to the first transceiving circuit; the first transceiver circuitry is configured to receive the first differential-mode signal coupled to the first transceiver circuitry by the first coupling transformer; the second coupling transformer is configured to couple a second differential-mode signal received from two of the power lines to the second transceiver circuit; the second transceiver circuit is configured to receive the second differential-mode signal coupled to the second transceiver circuit by the second coupling transformer.

With reference to the first aspect, in a possible implementation manner of the first aspect, the differential-mode coupling circuit further includes a third coupling transformer and a third transceiving circuit, the third coupling transformer is connected to two lines of the power lines, the third coupling transformer is coupled to the third transceiving circuit, two lines of the power lines connected by the third coupling transformer are different from two lines of the power lines connected by the first coupling transformer, and two lines of the power lines connected by the second coupling transformer are different from two lines of the power lines connected by the second coupling transformer, wherein the third coupling transformer is configured to couple a third differential-mode signal received from two lines of the power lines to the third transceiving circuit; the third transceiver circuit is configured to receive the third differential-mode signal coupled to the third transceiver circuit by the third coupling transformer.

With reference to the first aspect, in one possible implementation manner of the first aspect, the differential mode coupling circuit includes a fourth coupling transformer, a fourth transceiving circuit, a fifth coupling transformer, and a fifth transceiving circuit, the fourth coupling transformer is connected to at least two lines of the power line, the fourth coupling transformer is coupled to the fourth transceiving circuit, the fifth coupling transformer is connected with at least two lines of the power lines, the fifth coupling transformer is coupled to the fifth transceiving circuit, at least two wires in the power line are two wires of a live wire, a zero wire and a ground wire or the live wire, the zero wire and the ground wire, at least one of the fourth coupling transformer and the fifth coupling transformer is connected with the live wire, the zero wire and the ground wire, wherein the fourth coupling transformer is configured to couple a fourth differential-mode signal received from at least two of the power lines to the fourth transceiver circuit; the fourth transceiving circuitry to receive the fourth differential-mode signal that the fourth coupling transformer is coupled to the fourth transceiving circuitry; the fifth coupling transformer is configured to couple a fifth differential-mode signal received from at least two of the power lines to the fifth transceiver circuit; the fifth transceiver circuit is configured to receive the fifth differential-mode signal coupled to the fifth transceiver circuit by the fifth coupling transformer.

With reference to the first aspect, in a possible implementation manner of the first aspect, the differential-mode coupling circuit further includes a sixth coupling transformer and a sixth transceiving circuit, the sixth coupling transformer is connected to at least two lines of the power line, and the sixth coupling transformer is coupled to the sixth transceiving circuit, where the sixth coupling transformer is configured to couple a sixth differential-mode signal received from at least two lines of the power line to the sixth transceiving circuit; the sixth transceiving circuitry to receive the sixth differential mode signal that the sixth coupling transformer is coupled to the sixth transceiving circuitry.

With reference to the first aspect, in a possible implementation manner of the first aspect, the noise processing circuit includes an analog interface, an analog front end, a digital interface, and a digital front end, where the analog front end is connected to the differential-mode coupling circuit and the common-mode coupling circuit through the analog interface, the digital front end is connected to the analog front end through the digital interface, and the analog front end includes an adjustable amplifier and an analog-to-digital converter, where the analog interface is configured to receive the differential-mode signal and the common-mode signal; the adjustable amplifier is used for amplifying the differential mode signal and the common mode signal received by the analog interface to obtain an amplified differential mode signal and an amplified common mode signal; the analog-to-digital converter is used for sampling the amplified differential mode signal and the amplified common mode signal to obtain a digital signal; the digital interface is used for receiving the digital signal; the digital front end is used for processing the digital signals received by the digital interface so as to eliminate noise.

In a second aspect, an embodiment of the present application provides a signal transceiving method for power line communication, which is applied to a signal transceiving circuit for power line communication, where the circuit includes a differential mode coupling circuit, a common mode coupling circuit, and a noise processing circuit, where the differential mode coupling circuit and the common mode coupling circuit are respectively connected to a power line, the noise processing circuit is connected to the differential mode coupling circuit and the common mode coupling circuit, and the power line includes at least one of: a live wire, a neutral wire, and a ground wire, the method comprising: the differential mode coupling circuit is used for coupling and receiving differential mode signals on the power line; the common mode coupling circuit is coupled with and receives a common mode signal on the power line; the noise processing circuit processes the common mode signal and the differential mode signal to eliminate noise in the differential mode signal.

In the method, the common-mode signal on the power line is obtained by introducing the common-mode coupling circuit, and because the noise in the differential-mode signal obtained by the differential-mode coupling circuit has correlation with the noise in the common-mode signal, the noise in the received signal can be eliminated by processing the differential-mode signal and the common-mode signal by the noise processing circuit, so that the performance of power line communication is improved.

In combination with the second aspect, in a possible implementation manner of the second aspect, the differential-mode coupling circuit includes at least one coupling transformer and at least one transceiver circuit, each of the at least one coupling transformer is connected to at least two lines of the power line, each of the at least one coupling transformer is coupled to one transceiver circuit of the at least one transceiver circuit, and the differential-mode coupling circuit is configured to receive a differential-mode signal on the power line by coupling, including: each of the at least one coupling transformer couples differential mode signals received from at least two of the power lines to one of the at least one transceiver circuit; each of the at least one transceiver circuit receives the differential mode signal that the each coupling transformer couples to the each transceiver circuit.

With reference to the second aspect, in a possible implementation manner of the second aspect, the common mode coupling circuit includes a common mode transformer and a common mode signal receiving circuit, the common mode transformer is connected to the live wire, the neutral wire and the ground wire, the common mode transformer is coupled to the common mode signal receiving circuit, and the common mode coupling circuit is coupled to receive a common mode signal on the power line and includes: the common mode transformer couples common mode signals received from the live wire, the zero wire and the ground wire to the common mode signal receiving circuit; the common mode signal receiving circuit receives the common mode signal that the common mode transformer is coupled to the common mode signal receiving circuit.

With reference to the second aspect, in a possible implementation manner of the second aspect, the differential-mode coupling circuit includes a first coupling transformer, a first transceiver circuit, a second coupling transformer and a second transceiver circuit, the first coupling transformer is connected to two lines of the power line, the first coupling transformer is coupled to the first transceiver circuit, the second coupling transformer is connected to two lines of the power line, the second coupling transformer is coupled to the second transceiver circuit, the two lines of the power line are two of a live line, a neutral line and a ground line, the two lines of the power line connected by the first coupling transformer are different from the two lines of the power line connected by the second coupling transformer, and the differential-mode coupling circuit is configured to receive the differential-mode signal on the power line by coupling, and includes: the first coupling transformer couples first differential mode signals received from two of the power lines to the first transceiving circuit; the first transceiving circuitry receives the first differential mode signal that the first coupling transformer is coupled to the first transceiving circuitry; the second coupling transformer couples second differential mode signals received from two of the power lines to the second transceiving circuitry; the second transceiver circuit receives the second differential mode signal that the second coupling transformer couples to the second transceiver circuit.

With reference to the second aspect, in a possible implementation manner of the second aspect, the differential-mode coupling circuit further includes a third coupling transformer and a third transceiver circuit, the third coupling transformer is connected to two lines of the power lines, the third coupling transformer is coupled to the third transceiver circuit, two lines of the power lines connected by the third coupling transformer are different from two lines of the power lines connected by the first coupling transformer, and two lines of the power lines connected by the second coupling transformer are different from two lines of the power lines connected by the second coupling transformer, and the differential-mode coupling circuit is coupled to receive the differential-mode signal on the power lines, and further includes: the third coupling transformer couples third differential mode signals received from two of the power lines to the third transceiving circuit; the third transceiving circuitry receives the third differential mode signal that the third coupling transformer is coupled to the third transceiving circuitry.

With reference to the second aspect, in one possible implementation manner of the second aspect, the differential mode coupling circuit includes a fourth coupling transformer, a fourth transceiving circuit, a fifth coupling transformer, and a fifth transceiving circuit, the fourth coupling transformer is connected to at least two lines of the power line, the fourth coupling transformer is coupled to the fourth transceiving circuit, the fifth coupling transformer is connected with at least two lines of the power line, the fifth coupling transformer is coupled to the fifth transceiving circuit, at least two wires in the power line are two wires of a live wire, a zero wire and a ground wire or the live wire, the zero wire and the ground wire, at least one of the fourth coupling transformer and the fifth coupling transformer is connected with the live wire, the zero wire and the ground wire, and the differential mode coupling circuit is coupled to receive the differential mode signal on the power line and comprises: the fourth coupling transformer couples fourth differential mode signals received from at least two of the power lines to the fourth transceiving circuitry; the fourth transceiving circuitry receives the fourth differential mode signal that the fourth coupling transformer couples to the fourth transceiving circuitry; the fifth coupling transformer couples fifth differential mode signals received from at least two of the power lines to the fifth transceiving circuitry; the fifth transceiving circuitry receives the fifth differential mode signal that the fifth coupling transformer is coupled to the fifth transceiving circuitry.

With reference to the second aspect, in a possible implementation manner of the second aspect, the differential-mode coupling circuit further includes a sixth coupling transformer and a sixth transceiving circuit, the sixth coupling transformer is connected to at least two lines of the power line, the sixth coupling transformer is coupled to the sixth transceiving circuit, and the differential-mode coupling circuit is coupled to receive the differential-mode signal on the power line, and further includes: the sixth coupling transformer couples sixth differential mode signals received from at least two of the power lines to the sixth transceiving circuitry; the sixth transceiving circuitry receives the sixth differential mode signal that the sixth coupling transformer is coupled to the sixth transceiving circuitry.

With reference to the second aspect, in a possible implementation manner of the second aspect, the noise processing circuit includes an analog interface, an analog front end, a digital interface, and a digital front end, the analog front end is connected to the differential-mode coupling circuit and the common-mode coupling circuit through the analog interface, the digital front end is connected to the analog front end through the digital interface, the analog front end includes an adjustable amplifier and an analog-to-digital converter, and the noise processing circuit processes the common-mode signal and the differential-mode signal to eliminate noise in the differential-mode signal includes: the analog interface receives the differential mode signal and the common mode signal; the adjustable amplifier amplifies the differential mode signal and the common mode signal received by the analog interface to obtain an amplified differential mode signal and an amplified common mode signal; the analog-to-digital converter samples the amplified differential mode signal and the amplified common mode signal to obtain a digital signal; the digital interface receives the digital signal; and the digital front end processes the digital signal received by the digital interface so as to eliminate noise.

Drawings

FIG. 1a is a schematic diagram of a Delta-type differential mode coupling circuit;

FIG. 1b is a schematic diagram of a T-type differential mode coupling circuit;

FIG. 1c is a schematic diagram of noise variation;

FIG. 1d is a schematic diagram of the variation of noise generated by a German-West spotlight over an AC cycle;

FIG. 1e is a schematic diagram of a received signal under interference from a Delwey spotlight;

fig. 2a is a schematic diagram of a signal transceiver circuit for power line communication according to an embodiment of the present disclosure;

FIG. 2b is a schematic illustration of the correlation of differential mode electrical noise to common mode electrical noise;

FIG. 3 is a schematic structural diagram of the common mode transformer in FIG. 2 a;

fig. 4a is a schematic diagram of a power line communication system according to an embodiment of the present application;

FIG. 4b is a schematic diagram of the differential mode coupling circuit 2 and the common mode coupling circuit included in the electronic device 2 of FIG. 4 a;

FIG. 4c is a schematic diagram of another differential mode coupling circuit 2 and a common mode coupling circuit included in the electronic device 2 of FIG. 4 a;

fig. 5a is a schematic diagram of another power line communication system provided in an embodiment of the present application;

FIG. 5b is a schematic diagram of the differential mode coupling circuit 4 and the common mode coupling circuit included in the electronic device 4 of FIG. 5 a;

FIG. 5c is a schematic diagram of another differential mode coupling circuit 4 and a common mode coupling circuit included in the electronic device 4 of FIG. 5 a;

fig. 6 is a schematic diagram of a noise processing circuit according to an embodiment of the present disclosure;

fig. 7 is a schematic diagram of another signal transceiver circuit for power line communication according to an embodiment of the present disclosure;

fig. 8 is a schematic diagram of a signal transceiving method for power line communication according to an embodiment of the present disclosure;

fig. 9 is a schematic diagram of another signal transceiving method for power line communication according to an embodiment of the present disclosure;

fig. 10 is a schematic diagram of another signal transceiving method for power line communication according to an embodiment of the present disclosure;

fig. 11 is a schematic diagram of performance gain achieved by receiving signals through a signal transceiver circuit according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application.

Hereinafter, some terms in the embodiments of the present application are explained to facilitate understanding by those skilled in the art.

The term "at least one" as used in the embodiments of the present application means one or more, and the "plurality" means two or more. "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone, wherein A and B can be singular or plural. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of the singular or plural items. For example, at least one (one) of a, b, or c, may represent: a, b, c, a-b, a-c, b-c, or a-b-c, wherein a, b, c may be single or multiple.

And, unless stated to the contrary, the embodiments of the present application refer to the ordinal numbers "first", "second", etc., for distinguishing a plurality of objects, and do not limit the sequence, timing, priority, or importance of the plurality of objects. For example, the first information and the second information are different information only for distinguishing them from each other, and do not indicate a difference in the contents, priority, transmission order, importance, or the like of the two kinds of information.

To facilitate understanding of the present application, the background of the present application is first presented herein:

power line communication: the Power Line Communication (PLC) technology is a communication method that uses power lines to transmit data and media signals, and is also called as a power line network. PLC technology uses existing low frequency (50/60 hz) power lines to transmit broadband data. Digital Subscriber Line (DSL) technology uses a telephone line for data transmission, and a Cable Modem (CM) uses a coaxial cable line of a cable television for data transmission, so that, relatively speaking, a network line basically does not need to be re-laid by using a power line communication technology, and the power line covers a wider area than the area covered by the lines of other carriers.

The broadband technology of power line communication mainly includes IEEE Homeplug AV and ITU-T g.hn at present, and both technologies adopt an Orthogonal Frequency Division Multiplexing (OFDM) modulation mode, wherein the OFDM modulation mode is favorable for ensuring stable and complete transmission of data in a communication environment with severe electromagnetic interference.

The advantage of power line communication is that the coverage of the power line is wide and naturally covers the homes and corridors of residents, but the load impedance on the power line changes in real time, the noise also changes in real time, the transmission rate on the power line is affected, and higher requirements are placed on the design of the transceiver. The most significant influence on power line communication is various electrical loads added on a power line, and time-varying load impedance change and time-varying noise change are introduced.

Electric cat: the modem for power line communication, which is a modem, is a modem (modem) for broadband internet access through a power line. Personal Computers (PCs), broadband internet devices (e.g., Asymmetric Digital Subscriber Line (ADSL) modems), set-top boxes, audio devices, monitoring devices, and other intelligent electrical devices are networked using existing power lines and socket assemblies in a home or office to transmit data, voice, and video. The modem has the characteristic of plug and play, and can transmit network IP digital signals through a common household power line.

Power line multiple input multiple output (mimo) technology: the power line multiple-input multiple-output (MIMO) technology refers to a technology for performing MIMO communication on three lines, namely live (L), neutral (N) and ground (PE). In the mimo technology, three lines of a power line can form two paths of signals, and the signals are generally transmitted and received by adopting a two-to-two transmission (2T2R) or a two-to-three transmission (2T3R) mode. At present, Delta type coupling circuits or T type coupling circuits are generally used for transmitting and receiving signals.

Referring to fig. 1a, fig. 1a is a schematic diagram of a Delta type differential mode coupling circuit. As shown in fig. 1a, the Delta-type differential mode coupling circuit includes three signal transceiving terminals D1, D2 and D3, D1, D2 and D3 are respectively used for transmitting or receiving signals, and further includes coupling transformers C1, C2 and C3, which are used for coupling differential mode signals transmitted by the signal transceiving terminals to the power lines or coupling differential mode signals received from the power lines to the signal transceiving terminals. When the 2T2R signaling method is adopted, two of the D1, D2, and D3 terminals are adopted to transmit or receive signals. For example, signals are transmitted and received by using D1 and D2, when signals are transmitted by using D1, C1 is connected with the live wire and the neutral wire, and C1 is coupled to D1, differential mode signals transmitted by D1 can be coupled to the live wire and the neutral wire through C1, and then the differential mode signals are transmitted through the live wire and the neutral wire; when signals are transmitted by using the D2, the C2 is connected with the live wire and the ground wire, and the C2 is coupled to the D2, the differential mode signals transmitted by the D2 can be coupled to the live wire and the ground wire by the C2, and then the differential mode signals are transmitted through the live wire and the ground wire; when the D1 is used to receive signals, the differential mode signals on the live and neutral lines can be coupled to the D1 through the C1, and then the D1 receives the differential mode signals on the live and neutral lines; when receiving signals using D2, differential mode signals on the hot and ground lines can be coupled to D2 through C2, and then D2 receives the differential mode signals on the hot and ground lines. When the 2T3R signaling method is adopted, two of the D1, D2, and D3 transmit signals or three of the D1, D2, and D3 receive signals. For example, signals are transmitted by using D1 and D2, signals are received by using D1, D2 and D3, when signals are transmitted by using D1, C1 is connected with the live wire and the neutral wire, and C1 is coupled to D1, differential mode signals transmitted by D1 can be coupled to the live wire and the neutral wire through C1, and then the differential mode signals are transmitted by the live wire and the neutral wire; when signals are transmitted by using the D2, the C2 is connected with the live wire and the ground wire, and the C2 is coupled to the D2, the differential mode signals transmitted by the D2 can be coupled to the live wire and the ground wire by the C2, and then the differential mode signals are transmitted through the live wire and the ground wire; when the D1 is used to receive signals, the differential mode signals on the live and neutral lines can be coupled to the D1 through the C1, and then the D1 receives the differential mode signals on the live and neutral lines; when receiving signals using D2, differential mode signals on the line and ground can be coupled to D2 through C2, and then D2 receives differential mode signals on the line and ground; when signals are received using D3, C3 connects to the neutral and ground wires and C3 couples to D3, the differential mode signals on the neutral and ground wires may be coupled to D3 via C3, and then D3 receives the differential mode signals on the neutral and ground wires.

Referring to fig. 1b, fig. 1b is a schematic diagram of a T-type differential mode coupling circuit. As shown in fig. 1b, the T-type differential mode coupling circuit includes two signal transceiving terminals T1 and T2, T1 and T2 are respectively used for transmitting or receiving signals, and further includes coupling transformers C4 and C5, which are used for coupling differential mode signals transmitted from the signal transceiving terminals to the power lines or coupling differential mode signals received from the power lines to the signal transceiving terminals. When the 2T2R signal transmission/reception method is adopted, the signals are transmitted/received using T1 and T2. When signals are transmitted by using T1, C4 is connected with the live wire and the zero wire, and C4 is coupled to T1, differential mode signals transmitted by T1 can be coupled to the live wire and the zero wire through C4, and then the differential mode signals are transmitted by the live wire and the zero wire; when a signal is sent by adopting T2, C5 is connected with a live wire, a zero wire and a ground wire, C5 is coupled to T2, a differential mode signal sent by T2 can be coupled to the live wire, the zero wire and the ground wire through C5, and then a differential mode signal is sent through the live wire, the zero wire and the ground wire (the common mode signal of the live wire and the zero wire and the differential mode signal of the live wire and the zero wire form a differential mode signal with the ground wire); when the T1 is used to receive signals, the differential mode signals on the live and neutral lines can be coupled to the T1 through the C4, and then the T1 receives the differential mode signals on the live and neutral lines; when the T2 is used to receive signals, the differential mode signals on the line, neutral and ground (common mode signals on the line and neutral, and then differential mode signals with the ground) can be coupled to T2 through C5, and then T2 receives the differential mode signals on the line, neutral and ground. When the signal transceiving mode of 2T3R is adopted, the T-type differential mode coupling circuit includes three signal transceiving ends, and two of the signal transceiving ends are adopted to transmit signals or three signal transceiving ends are adopted to receive signals. When signals are transmitted by two signal transceiving ends, reference may be made to the above-described transmission of signals through T1 and T2; when three transceiving terminals are used to receive signals, two of the transceiving terminals may receive signals through T1 and T2 as described above, and the other transceiving terminal may receive differential mode signals on the live line and the ground line, or differential mode signals on the neutral line and the ground line.

Noise of electric appliance: the appliance noise is one of the main noises in the power line communication, and is generally presented as various forms of impulse noise, and the amplitude of part of the appliance noise is large, so that the performance of the power line communication is greatly influenced. Meanwhile, the noise of the electric appliance has abundant frequency characteristics, and the real-time change of the noise of most electric appliances in the power line system has a periodic characteristic matched with an Alternating Current (AC) period.

Referring to fig. 1c, fig. 1c is a schematic diagram of noise variation. As shown in FIG. 1c, 1c-1 is a schematic diagram of the periodic variation of the alternating current. 1c-2 is a schematic diagram of the time variation of the channel responses of different frequencies, and the real-time variation of the channel responses has a periodic characteristic matched with the alternating current period. 1c-3 is a schematic diagram of the time variation of the noise, and the real-time variation of the noise has a periodic characteristic which is matched with the alternating current period.

The variety of types and models of electric appliances in actual households and working environments causes the diversity of noise characteristics in power line systems. In addition, noise generated by the same electric appliance has different noise characteristics in the power line cycle, and the variation of electric appliance noise received through different receiving paths is different. Referring to fig. 1d, fig. 1d is a schematic diagram of the noise generated by the delazey lamp varying within the ac cycle. Wherein, 1d-1, 1d-2 and 1d-3 are respectively schematic diagrams of the change of noise generated by the German and Western spotlight received by the three-way receiving path in the alternating current period.

The pulse amplitude of the electrical noise in the power line system is generally large, resulting in deterioration of the performance of the power line communication. Referring to fig. 1e, fig. 1e is a schematic diagram of a received signal under the interference of the delazey lamp. As shown in fig. 1e, the received signal collected at 40dB attenuation is greatly affected by the noise generated by the german spotlight, and thus, the demodulation performance is affected.

As described above in the background of the present application, the technical features of the embodiments of the present application are described below.

Referring to fig. 2a, fig. 2a is a schematic diagram of a signal transceiving circuit for power line communication according to an embodiment of the present disclosure. As shown in fig. 2a, the signal transceiving circuit includes a differential mode coupling circuit 201, a common mode coupling circuit 202, and a noise processing circuit 203. The signal transceiving circuit is applied to an electronic device, and the electronic device can be a power modem.

The differential mode coupling circuit 201 and the common mode coupling circuit 202 are respectively connected to a power line, the noise processing circuit 203 is connected to the differential mode coupling circuit 201 and the common mode coupling circuit 202, and the power line includes at least one of the following: live, neutral and ground wires.

And the differential mode coupling circuit 201 is used for coupling and receiving the differential mode signal on the power line. The differential mode signals on the power lines comprise differential mode signals on two lines of the power lines or differential mode signals on three lines of the power lines. The differential mode signals on the two lines in the power line comprise differential mode signals on the live line and the zero line, differential mode signals on the live line and the ground line, or differential mode signals on the zero line and the ground line. The differential mode signals on the three lines of the power line comprise differential mode signals formed by common mode signals on the live line and the zero line and the ground line, differential mode signals formed by common mode signals on the live line and the ground line and the zero line, or differential mode signals formed by common mode signals on the zero line and the ground line and the live line.

Optionally, the differential mode coupling circuit 201 includes at least one coupling transformer and at least one transceiver circuit, wherein each coupling transformer of the at least one coupling transformer is connected to at least two lines of the power line, and each coupling transformer is coupled to one transceiver circuit of the at least one transceiver circuit. Each coupling transformer is configured to couple differential mode signals received from at least two of the power lines to one of the at least one transceiver circuit, and each of the at least one transceiver circuit is configured to receive differential mode signals coupled to the at least one transceiver circuit from the each coupling transformer.

The common mode coupling circuit 202 is configured to couple and receive a common mode signal on a power line. The common-mode signals on the power line are common-mode signals on a live wire, a zero wire and a ground wire.

Optionally, the common mode coupling circuit 202 includes a common mode transformer and a common mode signal receiving circuit, wherein the common mode transformer is connected to the live line, the neutral line and the ground line, and the common mode transformer is coupled to the common mode signal receiving circuit. The common mode transformer is used for coupling common mode signals received from the live wire, the zero wire and the ground wire to the common mode signal receiving circuit, and the common mode signal receiving circuit is used for receiving the common mode signals coupled to the common mode signal receiving circuit by the common mode transformer.

And the noise processing circuit 203 is used for processing the common mode signal and the differential mode signal to eliminate noise in the differential mode signal. In the power line communication system, signals are transmitted through a power line, and various electrical appliances are added to the power line, so that electrical appliance noise is included in the signals transmitted through the power line, differential mode signals (including differential mode electrical appliance noise) on the power line can be obtained through coupling by the differential mode coupling circuit 201, and common mode signals (including common mode electrical appliance noise) on the power line can be obtained through introducing the common mode coupling circuit 202 because the electrical appliance noise has strong common mode characteristics. The electrical noise in the differential mode signal obtained by coupling through the differential mode coupling circuit 201 has correlation with the electrical noise obtained by coupling through the common mode coupling circuit 202, so that the electrical noise in the differential mode signal can be eliminated by processing the common mode signal and the differential mode signal through the noise processing circuit 203, and the performance of power line communication is improved.

The correlation between the electrical noise in the differential mode and the electrical noise in the common mode is shown in fig. 2 b. As shown in fig. 2b, 2b-1 is a schematic diagram of the time domain noise collected through the differential mode path and the common mode path, wherein the solid line is a schematic diagram of the electrical noise of the differential mode received through the differential mode coupling circuit, and the dotted line is a schematic diagram of the electrical noise of the common mode received through the common mode coupling circuit. 2b-2 is a schematic diagram of a correlation coefficient of the electrical appliance noise in the differential mode and the electrical appliance noise in the common mode, and it can be seen that the electrical appliance noise in the differential mode and the electrical appliance noise in the common mode have strong correlation by performing cross-correlation operation.

The operation principle of the common-mode transformer in fig. 2a is described in detail below, and the structure of the common-mode transformer is shown in fig. 3. The common mode transformer comprises a signal input port, a differential mode signal output port and a common mode signal output port, wherein the signal input port comprises a port 1, a port 3 and a port 5, the differential mode signal output port comprises a port 2, a port 4 and a port 6, and the common mode signal output port comprises a port 7 and a port 8. The common mode transformer is connected with three lines of the power line. For example, the live wire is connected to port 1 and port 2, and a signal on the live wire is input to the common mode transformer through port 1 and output through port 2; the zero line is connected with the port 3 and the port 4, and a signal on the zero line is input into the common mode transformer through the port 3 and is output through the port 4; the ground line is connected with the port 5 and the port 6, and a signal on the ground line is input into the common mode transformer through the port 5 and is output through the port 6. The coil A, the coil B, the coil C and the coil D are wound on one magnetic core together, when a differential mode signal flows through the common mode transformer, the common mode transformer can be equivalent to a common mode inductor, magnetic fields generated by the differential mode signal are mutually counteracted, and the differential mode signal can pass through an output port of the differential mode signal without attenuation basically; when a common-mode signal flows through the common-mode transformer, magnetic fields generated by the common-mode signal are mutually enhanced, at the moment, for a differential-mode signal output port, the coil A, the coil B and the coil C are high in impedance, the differential-mode signal output port has a strong attenuation effect on the common-mode signal, and for the common-mode signal output port, the coil D induces magnetic flux of the common-mode signal, and further generates induced electromotive force and passes through the common-mode signal output port. Therefore, when a signal on the power line is input to the common mode transformer through the port 1, the port 3, and the port 5 and output through the port 2, the port 4, and the port 6, the differential mode signal loss is small, and the common mode signal loss is large. Signals on the power line are input into the common mode transformer through the port 1, the port 3 and the port 5, when the signals are output through the port 7 and the port 8, the differential mode signal loss is large, and the common mode signal loss is small, so that the common mode signals on the three lines of the power line can be coupled and received through the common mode transformer.

Referring to fig. 4a, fig. 4a is a schematic diagram of a power line communication system according to an embodiment of the present disclosure. As shown in fig. 4a, on the basis of Delta type differential mode coupling circuit, 2T2R, a common mode coupling circuit is introduced as a third path receiving. On the signal transmission side, a signal is transmitted by the electronic apparatus 1, and the electronic apparatus 1 includes a differential mode coupling circuit 1. Specifically, a first transceiving circuit and a second transceiving circuit of the differential mode coupling circuit 1 are used for sending differential mode signals, the differential mode signals are coupled to the power line through the differential mode coupling circuit 1, so that the differential mode signals are sent by adopting a live wire and a zero wire, the differential mode signals are sent by adopting the live wire and a ground wire, and then the signals sent by the electronic equipment 1 are transmitted through the power line. On the signal receiving side, a signal is received by the electronic device 2, the electronic device 2 including a differential mode coupling circuit 2 and a common mode coupling circuit. Specifically, signals on three lines of the power line firstly pass through a common mode transformer, the common mode transformer couples out common mode signals on the live wire, the zero line and the ground wire, the common mode signal is received through a common mode signal receiving circuit, then the signals on the three lines of the power line are input into a differential mode coupling circuit 2, differential mode signals on the power line are coupled to a first transceiving circuit and a second transceiving circuit of the differential mode coupling circuit 2, and the first transceiving circuit and the second transceiving circuit of the differential mode coupling circuit 2 receive the differential mode signals, so that the differential mode signals on the live wire and the zero line are received, and the differential mode signals on the live wire and the ground wire are received.

Referring to fig. 4b, fig. 4b is a schematic diagram of the differential mode coupling circuit 2 and the common mode coupling circuit included in the electronic device 2 in fig. 4 a. As shown in fig. 4b, the differential-mode coupling circuit 2 includes a first coupling transformer 401, a first transceiver circuit 402, a second coupling transformer 403, and a second transceiver circuit 404, and the common-mode coupling circuit includes a common-mode transformer 405 and a common-mode signal receiving circuit 406. The first coupling transformer 401 is connected to the live wire and the neutral wire, the first coupling transformer 401 is coupled to the first transceiver circuit 402, an input terminal TX0 of the first transceiver circuit 402 is used for transmitting signals, and an output terminal RX0 of the first transceiver circuit 402 is used for receiving signals. The second coupling transformer 403 is connected to the hot and ground wires, the second coupling transformer 403 is coupled to the second transceiver circuit 404, an input terminal TX1 of the second transceiver circuit 404 is used for transmitting signals, and an output terminal RX1 of the second transceiver circuit 404 is used for receiving signals. Common mode transformer 405 is connected to hot, neutral and ground wires, common mode transformer 405 is coupled to common mode signal receiving circuit 406, and output RX2 of common mode signal receiving circuit 406 is used for receiving signals.

Specifically, when receiving signals on the power line, signals on the live and neutral lines are input to the first coupling transformer 401, the first coupling transformer 401 couples first differential-mode signals received from the live and neutral lines to the first transceiver circuit 402, and receives the first differential-mode signals through the output terminal RX0 of the first transceiver circuit 402. The signals on the hot and ground lines are input to a second coupling transformer 403. the second coupling transformer 403 couples a second differential mode signal received from the hot and ground lines to the second transceiver circuit 404 and receives the second differential mode signal via an output RX1 of the second transceiver circuit 404. The signals on the line, neutral and ground are input to a common mode transformer 405, respectively, which common mode transformer 405 couples the common mode signals received from the line, neutral and ground to a common mode signal receiving circuit 406 and receives the common mode signal through an output RX2 of the common mode signal receiving circuit 406.

In the differential mode coupling circuit 2 shown in fig. 4b, the first differential mode signal is received through the output terminal RX0 of the first transceiver circuit 402, and the second differential mode signal is received through the output terminal RX1 of the second transceiver circuit 404, and due to various electrical appliances added to the power line, electrical appliance noise is included in the signal transmitted on the power line, that is, the first differential mode signal and the second differential mode signal both include electrical appliance noise in the differential mode. Meanwhile, since the electrical noise has a strong common mode characteristic, a common mode signal (including the common mode electrical noise) on the power line can be coupled by introducing the common mode transformer 405, and the common mode signal is received by the output terminal RX2 of the common mode signal receiving circuit 406. Because the electrical noise in the first differential mode signal and the second differential mode signal has correlation with the electrical noise in the common mode, the received three signals (the first differential mode signal, the second differential mode signal and the common mode signal) can be processed by a digital end algorithm subsequently to eliminate the electrical noise in the differential mode signals, so that the performance of power line communication is improved.

In one possible example, the differential mode coupling circuit 2 further comprises a third coupling transformer 407 and a third transceiving circuit 408, and the schematic diagrams of the differential mode coupling circuit 2 and the common mode coupling circuit are shown in fig. 4 c. Wherein, a third coupling transformer 407 is connected to the neutral and ground wires, the third coupling transformer 407 is coupled to a third transceiver circuit 408, and an output terminal RX3 of the third transceiver circuit 408 is used for receiving signals.

Specifically, the signals on the neutral and ground lines are input to a third coupling transformer 407, and the third coupling transformer 407 couples a third differential mode signal received from the neutral and ground lines to the third transceiver 408, and receives the third differential mode signal through an output terminal RX3 of the third transceiver 408.

In the differential mode coupling circuit 2 shown in fig. 4c, the first differential mode signal is received through the output terminal RX0 of the first transceiver circuit 402, the second differential mode signal is received through the output terminal RX1 of the second transceiver circuit 404, and the third differential mode signal is received through the output terminal RX3 of the third transceiver circuit 408, and since various electrical appliances are added to the power line, electrical appliance noise is included in the signal transmitted on the power line, that is, the first differential mode signal, the second differential mode signal, and the third differential mode signal all include electrical appliance noise in the differential mode. Meanwhile, since the electrical noise has a strong common mode characteristic, a common mode signal (including the common mode electrical noise) on the power line can be coupled by introducing the common mode transformer 405, and the common mode signal is received by the output terminal RX2 of the common mode signal receiving circuit 406. Because the electrical noise in the first differential mode signal, the second differential mode signal and the third differential mode signal has correlation with the electrical noise in the common mode, the received four paths of signals (the first differential mode signal, the second differential mode signal, the third differential mode signal and the common mode signal) can be processed by a digital end algorithm subsequently to eliminate the electrical noise in the differential mode signals, so that the performance of power line communication is improved.

Referring to fig. 5a, fig. 5a is a schematic diagram of another power line communication system provided in an embodiment of the present application. As shown in fig. 5a, on the basis of the T-type differential mode coupling circuit, 2T2R, a common mode coupling circuit is introduced as a third path receiving. On the signal transmission side, a signal is transmitted by the electronic device 3, the electronic device 3 including a differential mode coupling circuit 3. Specifically, the differential mode signals are transmitted by the fourth transceiver circuit and the fifth transceiver circuit of the differential mode coupling circuit 3, and are coupled to the power line through the differential mode coupling circuit 3, so that the differential mode signals are transmitted by the live line and the zero line, the differential mode signals (the differential mode signals formed by the common mode signals on the live line and the zero line and the ground line) are transmitted by the live line, the zero line and the ground line, and then the signals transmitted by the electronic device 3 are transmitted through the power line. On the signal receiving side, a signal is received by the electronic device 4, the electronic device 4 including a differential mode coupling circuit 4 and a common mode coupling circuit. Specifically, signals on three lines of the power line firstly pass through a common mode transformer, the common mode transformer couples out common mode signals on the live line, the zero line and the ground line, the common mode signal is received through a common mode signal receiving circuit, then the signals on the three lines of the power line are input into a differential mode coupling circuit 4, differential mode signals on the power line are coupled to a fourth transceiving circuit and a fifth transceiving circuit of the differential mode coupling circuit 4, the fourth transceiving circuit and the fifth transceiving circuit of the differential mode coupling circuit 4 receive the differential mode signals, and therefore differential mode signals on the live line and the zero line are received, and differential mode signals on the live line, the zero line and the ground line are received (differential mode signals formed by the common mode signals on the live line and the zero line and the ground line).

Referring to fig. 5b, fig. 5b is a schematic diagram of the differential mode coupling circuit 4 and the common mode coupling circuit included in the electronic device 4 in fig. 5 a. As shown in fig. 5b, the differential-mode coupling circuit 4 includes a fourth coupling transformer 501, a fourth transceiver circuit 502, a fifth coupling transformer 503 and a fifth transceiver circuit 504, and the common-mode coupling circuit includes a common-mode transformer 505 and a common-mode signal receiving circuit 506. The fourth coupling transformer 501 is connected to the live wire and the neutral wire, the fourth coupling transformer 501 is coupled to the fourth transceiver circuit 502, an input terminal TX0 of the fourth transceiver circuit 502 is used for transmitting signals, and an output terminal RX0 of the fourth transceiver circuit 502 is used for receiving signals. The fifth coupling transformer 503 is connected to the live, neutral and ground wires, the fifth coupling transformer 503 is coupled to the fifth transceiver circuit 504, an input terminal TX1 of the fifth transceiver circuit 504 is used for transmitting signals, and an output terminal RX1 of the fifth transceiver circuit 504 is used for receiving signals. The common mode transformer 505 is connected to the live, neutral and ground wires, the common mode transformer 505 is coupled to the common mode signal receiving circuit 506, and an output terminal RX2 of the common mode signal receiving circuit 506 is used for receiving signals.

Specifically, when receiving signals on the power line, signals on the live and neutral lines are input to the fourth coupling transformer 501, the fourth coupling transformer 501 couples the fourth differential-mode signals received from the live and neutral lines to the fourth transceiver circuit 502, and receives the fourth differential-mode signals through the output terminal RX0 of the fourth transceiver circuit 502. The signals on the live, neutral and ground lines are input to a fifth coupling transformer 503, and the fifth coupling transformer 503 couples fifth differential mode signals (differential mode signals composed of common mode signals on the live and neutral lines and the ground line) received from the live, neutral and ground lines to the fifth transceiving circuit 504 and receives the fifth differential mode signals through an output RX1 of the fifth transceiving circuit 504. The signals on the live, neutral and ground lines are input to a common mode transformer 505, respectively, which common mode transformer 505 couples the common mode signals received from the live, neutral and ground lines to a common mode signal receiving circuit 506 and receives the common mode signal through an output RX2 of the common mode signal receiving circuit 506.

In the differential-mode coupling circuit 4 shown in fig. 5b, the output terminal RX0 of the fourth transceiver circuit 502 receives the fourth differential-mode signal, and the output terminal RX1 of the fifth transceiver circuit 504 receives the fifth differential-mode signal, and due to various electrical appliances added to the power line, the signal transmitted on the power line includes electrical appliance noise, that is, the fourth differential-mode signal and the fifth differential-mode signal both include electrical appliance noise in the differential mode. Meanwhile, since the electrical noise has a strong common mode characteristic, a common mode signal (including the common mode electrical noise) on the power line can be coupled by introducing the common mode transformer 505, and the common mode signal is received by the output terminal RX2 of the common mode signal receiving circuit 506. Because the electrical noise in the fourth differential mode signal and the fifth differential mode signal has correlation with the electrical noise in the common mode, the received three signals (the fourth differential mode signal, the fifth differential mode signal and the common mode signal) can be processed by a digital end algorithm subsequently to eliminate the electrical noise in the differential mode signals, so that the performance of power line communication is improved.

In one possible example, the differential mode coupling circuit 4 further comprises a sixth coupling transformer 507 and a sixth transceiving circuit 508, and the schematic diagrams of the differential mode coupling circuit 4 and the common mode coupling circuit are shown in fig. 5 c. Wherein, a sixth coupling transformer 507 is connected to the live wire and the ground wire, the sixth coupling transformer 507 is coupled to the sixth transceiver circuit 508, and an output terminal RX3 of the sixth transceiver circuit 508 is used for receiving signals.

Specifically, the signals on the hot and ground lines are input to the sixth coupling transformer 507, the sixth coupling transformer 507 couples the sixth differential-mode signal received from the hot and ground lines to the sixth transceiving circuit 508, and the sixth differential-mode signal is received through the output terminal RX3 of the sixth transceiving circuit 508.

In the differential-mode coupling circuit 4 shown in fig. 5c, the output terminal RX0 of the fourth transceiver circuit 502 receives the fourth differential-mode signal, the output terminal RX1 of the fifth transceiver circuit 504 receives the fifth differential-mode signal, and the output terminal RX3 of the sixth transceiver circuit 508 receives the sixth differential-mode signal, and as various electrical appliances are added to the power line, electrical appliance noise is included in the signal transmitted on the power line, that is, the fourth differential-mode signal, the fifth differential-mode signal, and the sixth differential-mode signal all include electrical appliance noise in the differential mode. Meanwhile, since the electrical noise has a strong common mode characteristic, a common mode signal (including the common mode electrical noise) on the power line can be coupled by introducing the common mode transformer 505, and the common mode signal is received by the output terminal RX2 of the common mode signal circuit 506. Because the electrical noise in the fourth differential mode signal, the fifth differential mode signal and the sixth differential mode signal has correlation with the electrical noise in the common mode, the received four paths of signals (the fourth differential mode signal, the fifth differential mode signal, the sixth differential mode signal and the common mode signal) can be processed by a digital end algorithm subsequently to eliminate the electrical noise in the differential mode signals, so that the performance of power line communication is improved.

Referring to fig. 6, fig. 6 is a schematic diagram of a noise processing circuit according to an embodiment of the present disclosure. As shown in fig. 6, the noise processing circuit includes an analog interface 601, an analog front end (analog front end)602, a digital interface 603, and a digital front end (digital front end) 604.

The analog front end 602 is connected to the differential-mode coupling circuit and the common-mode coupling circuit in the above embodiments through the analog interface 601, the digital front end 604 is connected to the analog front end 602 through the digital interface 603, and the analog front end 602 includes a tunable amplifier (programmable-gain amplifier)6021 and an analog-to-digital converter (analog digital converter) 6022.

The analog interface 601 is configured to receive the differential mode signal and the common mode signal obtained by the differential mode coupling circuit and the common mode coupling circuit. The differential mode signal and the common mode signal obtained by the differential mode coupling circuit and the common mode coupling circuit comprise a combination of the following components: two paths of differential mode signals obtained by the differential mode coupling circuit 2 shown in fig. 4b and common mode signals obtained by the common mode coupling circuit, three paths of differential mode signals obtained by the differential mode coupling circuit 2 shown in fig. 4c and common mode signals obtained by the common mode coupling circuit, two paths of differential mode signals obtained by the differential mode coupling circuit 4 shown in fig. 5b and common mode signals obtained by the common mode coupling circuit, three paths of differential mode signals obtained by the differential mode coupling circuit 4 shown in fig. 5c and common mode signals obtained by the common mode coupling circuit.

The adjustable amplifier 6021 is configured to amplify the differential-mode signal and the common-mode signal received by the analog interface 601 to obtain an amplified differential-mode signal and an amplified common-mode signal.

Analog-to-digital converter 6022 is configured to sample the amplified differential-mode signal and common-mode signal to obtain a digital signal.

A digital interface 603 for receiving the digital signal.

A digital front end 604 for processing the digital signal received by the digital interface 603 to remove noise.

Optionally, the analog interface 601 further includes a line driver (line driver), and the line driver is configured to drive signal power on the amplifying line.

Optionally, the analog front end 602 and the digital front end 604 are located on the same chip, or the analog front end 602 and the digital front end 604 are located on two separate chips, or the analog-to-digital converter 6022 and the digital front end 604 in the analog front end 602 are located on one chip, and the adjustable amplifier 6021 and the line driver in the analog front end 602 are located on the other chip.

Optionally, the digital front end 604 includes a noise cancellation module, and the digital front end 604 processes the received digital signal to implement receiving and demodulating of the signal. According to the foregoing, the common mode noise and the differential mode noise have correlation, so that the noise characteristic of the common mode signal can be utilized to eliminate the electrical noise in the differential mode signal by a digital processing method, thereby improving the performance of the power line communication. While various schemes exist in the industry for canceling noise based on the known characteristics of the noise, in the embodiments of the present invention, the noise can be processed by a digital side algorithm, such as minimum mean square error-interference suppression combining (MMSE-IRC) algorithm. The MMSE-IRC algorithm is a commonly used MIMO receiver technique, and when interference in a received signal is mainly colored interference (the interference has a certain correlation on a plurality of receiving lines, and is not completely independent), the interference on the combined received signal can be mutually cancelled through specific weighting, so that the interference suppression effect is achieved, that is, the noise in the received signal is eliminated.

Specifically, when the MMSE-IRC algorithm is used to perform noise cancellation processing on the received signal, the process of performing noise cancellation processing on the received signal by the digital front end 604 is as follows:

the signal received by the digital front end 604 is represented as:

Y(k)＝H(k)S(k)+N(k)

wherein Y (k) is N on the k carrier _r A received signal of x1 dimension, S (k) being N _t The x 1-dimensional transmission signal, n (k) is the noise plus interference on the kth carrier, and s (k) is set to mean 0 and variance 1.

If the received signal is equalized, the equalized received signal is represented as:

R(k)＝W(k)Y(k)＝W(k)H(k)S(k)+W(k)N(k)

wherein W (k) is an equalization matrix and W (k) is N _t ×N _r A dimension matrix.

The minimum mean square error and the maximum signal-to-interference-and-noise ratio are taken as the criteria, and the following are provided:

namely, the method comprises the following steps:

J＝E[||W(k)Y(k)-S(k)|| ² ]＝E[tr((W(k)Y(k)-S(k))(W(k)Y(k)-S(k)) ^H )]

＝Ε[tr(W(k)Y(k)Y(k) ^H W(k) ^H +S(k)S(k) ^H -W(k)Y(k)S(k) ^H -S(k)Y(k) ^H W(k) ^H )]

the above formula itemizing pairs W (k) ^H The partial derivatives are calculated to obtain:

W(k)E[Y(k)Y(k) ^H ]＝Ε[S(k)Y(k) ^H ]

namely, the method comprises the following steps:

W(k)E[(H(k)S(k)+N(k))(H(k)S(k)+N(k)) ^H ]＝Ε[S(k)(H(k)S(k)+N(k)) ^H ]

namely:

W(k)E[H(k)S(k)S(k) ^H H(k) ^H +H(k)S(k)N(k) ^H +N(k)S(k) ^H H(k) ^H +N(k)N(k) ^H ]

＝Ε[S(k)S(k) ^H H(k) ^H +S(k)N(k) ^H ]

according to S (k), if the mean is 0 and the variance is 1, then:

W(k)(H(k)H(k) ^H +Ε[N(k)N(k) ^H ])＝H(k) ^H

covariance matrix E [ N (k) with noise ^H ]Is R _uu (k) And obtaining an equalization matrix:

wherein R is _uu For noise covariance matrices, R is used when interference in multiple received signals is uncorrelated _uu Is 0, the Interference Rejection Combining (IRC) algorithm is reduced to the Maximum Ratio Combining (MRC) algorithm. The MRC algorithm corrects the phase of each path of received signals to be consistent, weights and sums the signals according to the signal-to-noise ratio as weight, and the combined received signals have the maximum signal-to-noise ratio but have no interference suppression effect and cannot reach the maximum signal-to-interference-and-noise ratio. The signal transceiving circuit provided by the embodiment of the application has correlation of interference in the received multipath signals, namely R _uu The received signal is processed by adopting the MMSE-IRC algorithm to achieve the maximization of the signal-to-interference-and-noise ratio, namely, the electrical appliance noise in the received signal is eliminated.

A system implementation of the signal transceiving circuit for power line communication is described below.

Referring to fig. 7, fig. 7 is a schematic diagram of another signal transceiving circuit for power line communication according to an embodiment of the present disclosure. As shown in fig. 7, the signal transceiver circuit is located on a single board, and the signal transceiver circuit includes a differential mode coupling circuit 7011, a common mode coupling circuit 7012, a first analog interface 7021, a second analog interface 7022, a third analog interface 7023, a first analog front end 7031, a second analog front end 7032, a third analog front end 7033, a first digital interface 7041, a second digital interface 7042, a third digital interface 7043, and a digital front end 705.

The differential mode coupling circuit 7011 and the common mode coupling circuit 7012 are located outside the chip and are respectively connected to a power line, where the power line includes at least one of a live line, a neutral line, and a ground line. The differential mode coupling circuit 7011 and the common mode coupling circuit 7012 may be the differential mode coupling circuit 2 and the common mode coupling circuit shown in fig. 4b, or the differential mode coupling circuit 7011 and the common mode coupling circuit 7012 may be the differential mode coupling circuit 4 and the common mode coupling circuit shown in fig. 5 b.

The first analog interface 7021, the second analog interface 7022, and the third analog interface 7023 are respectively connected to the differential mode coupling circuit 7011 and the common mode coupling circuit 7012, and are configured to receive three analog signals (including two differential mode signals and one common mode signal) obtained through the differential mode coupling circuit 7011 and the common mode coupling circuit 7012. The first analog interface 7021 and the second analog interface 7022 are respectively connected to the differential mode coupling circuit 7011, where the first analog interface 7021 is configured to receive a first channel of differential mode signals, and the second analog interface 7022 is configured to receive a second channel of differential mode signals. The third analog interface 7023 is connected to the common mode coupling circuit 7012, and the third analog interface 7023 is configured to receive a third common mode signal. Optionally, the first analog interface 7021, the second analog interface 7022, and the third analog interface 7023 include line drivers for driving signal power on the amplification line when transmitting a signal.

The first analog front end 7031 is connected to the first analog interface 7021, the second analog front end 7032 is connected to the second analog interface 7022, and the third analog front end 7033 is connected to the third analog interface 7023. The first analog front end 7031, the second analog front end 7032, and the third analog front end 7033 each include an adjustable amplifier for amplifying an analog signal and an analog-to-digital converter for sampling the analog signal. The first analog front end 7031 is configured to amplify and sample a first path of differential mode signals received by the first analog interface 7021 to obtain a first path of digital signals, the second analog front end 7032 is configured to amplify and sample a second path of differential mode signals received by the second analog interface 7022 to obtain a second path of digital signals, and the third analog front end 7033 is configured to amplify and sample a third path of common mode signals received by the third analog interface 7023 to obtain a third path of digital signals.

The first digital interface 7041 is connected to the first analog front end 7031, the second digital interface 7042 is connected to the second analog front end 7032, and the third digital interface 7043 is connected to the third analog front end 7033. The first digital interface 7041 is configured to receive a first path of digital signals obtained through the first analog front end 7031, the second digital interface 7042 is configured to receive a second path of digital signals obtained through the second analog front end 7032, and the third digital interface 7043 is configured to receive a third path of digital signals obtained through the third analog front end 7033.

The digital front end 705 is connected to a first digital interface 7041, a second digital interface 7042, and a third digital interface 7043, the digital front end 705 including a noise cancellation module 7051. The digital front end 705 is configured to process three paths of digital signals received through the first digital interface 7041, the second digital interface 7042, and the third digital interface 7043, so as to implement receiving and demodulating of the signals. The noise elimination module 7051 is configured to perform noise elimination processing on the received three paths of digital signals, so as to improve performance of power line communication. Specifically, the noise cancellation processing may be performed on the three paths of digital signals through a digital-side algorithm, which may be, for example, an MMSE-IRC algorithm.

Referring to fig. 8, fig. 8 is a schematic diagram of a signal transceiving method for power line communication according to an embodiment of the present application. As shown in fig. 8, the signal transceiving method is applied to a signal transceiving circuit of power line communication, the circuit includes a differential mode coupling circuit, a common mode coupling circuit, and a noise processing circuit, the differential mode coupling circuit and the common mode coupling circuit are respectively connected to a power line, the noise processing circuit is connected to the differential mode coupling circuit and the common mode coupling circuit, the power line includes at least one of: the signal transceiving method comprises the following steps of S801-S803:

and S801, coupling and receiving the differential mode signal on the power line by the differential mode coupling circuit.

The differential mode signals on the power lines comprise differential mode signals on two lines of the power lines or differential mode signals on three lines of the power lines. The differential mode signals on the two lines in the power line comprise differential mode signals on the live line and the zero line, differential mode signals on the live line and the ground line, or differential mode signals on the zero line and the ground line. The differential mode signals on the three lines of the power line comprise differential mode signals formed by common mode signals on the live line and the zero line and the ground line, differential mode signals formed by common mode signals on the live line and the ground line and the zero line, or differential mode signals formed by common mode signals on the zero line and the ground line and the live line.

And S802, the common mode coupling circuit is used for coupling and receiving the common mode signal on the power line.

The common-mode signals on the power line are common-mode signals on a live wire, a zero wire and a ground wire.

And S803, the noise processing circuit processes the common-mode signal and the differential-mode signal to eliminate noise in the differential-mode signal.

In the power line communication system, a signal is transmitted through a power line, and various electric appliances are added to the power line, so that electric appliance noise is included in the signal transmitted through the power line. In the signal transceiving method for power line communication, the differential mode coupling circuit couples and receives the differential mode signal on the power line, which includes differential mode electrical noise, and meanwhile, the common mode coupling circuit couples and receives the common mode signal on the power line, which includes common mode electrical noise, because the electrical noise has strong common mode characteristics. The electrical noise in the differential mode signal has correlation with the electrical noise in the common mode, so that the noise processing circuit processes the common mode signal and the differential mode signal, the electrical noise in the differential mode signal can be eliminated, and the performance of power line communication is improved.

Referring to fig. 9, fig. 9 is a schematic diagram of another signal transceiving method for power line communication according to an embodiment of the present application. As shown in fig. 9, the signal transceiving method is applied to a signal transceiving circuit for power line communication, which includes a differential mode coupling circuit, a common mode coupling circuit, and a noise processing circuit. The differential mode coupling circuit comprises a first coupling transformer, a first transceiving circuit, a second coupling transformer and a second transceiving circuit, and the common mode coupling circuit comprises a common mode transformer and a common mode signal receiving circuit. The first coupling transformer is connected with the live wire and the neutral wire, and the first coupling transformer is coupled to the first transceiver circuit. The second coupling transformer is connected to the hot and ground wires, the second coupling transformer being coupled to the second transceiving circuitry. The common mode transformer is connected with the live wire, the zero wire and the ground wire, and the common mode transformer is coupled to the common mode signal receiving circuit. The noise processing circuit comprises an analog interface, an analog front end, a digital interface and a digital front end, wherein the analog front end is connected with the differential mode coupling circuit and the common mode coupling circuit through the analog interface, the digital front end is connected with the analog front end through the digital interface, and the analog front end comprises an adjustable amplifier and an analog-to-digital converter. The signal transceiving method comprises the following steps of S901-S911:

and S901, coupling the first differential mode signals received from the live wire and the zero wire to a first transceiver circuit by using a first coupling transformer.

S902, the first transceiver circuit receives a first differential-mode signal coupled to the first transceiver circuit by the first coupling transformer.

And S903, coupling the second differential mode signal received from the live wire and the ground wire to a second transceiver circuit by using a second coupling transformer.

And S904, the second transceiver circuit receives a second differential-mode signal which is coupled to the second transceiver circuit by the second coupling transformer.

And S905, coupling the common-mode signals received from the live wire, the zero wire and the ground wire to a common-mode signal receiving circuit by using the common-mode transformer.

And S906, the common mode signal receiving circuit receives the common mode signal which is coupled to the common mode signal receiving circuit by the common mode transformer.

S907, the analog interface receives the first differential mode signal, the second differential mode signal and the common mode signal.

S908, the adjustable amplifier amplifies the first differential-mode signal, the second differential-mode signal, and the common-mode signal received by the analog interface to obtain an amplified differential-mode signal and an amplified common-mode signal.

And S909, the analog-to-digital converter samples the amplified differential mode signal and the amplified common mode signal to obtain a digital signal.

S910, the digital interface receives the digital signal.

And S911, the digital front end processes the digital signals received by the digital interface so as to eliminate noise.

Specifically, the noise cancellation processing may be performed on the digital signal through a digital-end algorithm, and the digital-end algorithm may be, for example, an MMSE-IRC algorithm.

In the above signal transceiving method, because various electrical appliances are added to the power line, the signal transmitted on the power line includes electrical appliance noise, that is, the differential mode electrical appliance noise is included in both of the two differential mode signals received by coupling. Meanwhile, the electrical noise has strong common-mode characteristics, so that the coupled and received common-mode signal comprises the common-mode electrical noise. Because the electrical appliance noise in the two paths of differential mode signals has correlation with the common-mode electrical appliance noise, the electrical appliance noise can be eliminated by processing the received digital signals through a digital end algorithm, so that the performance of power line communication is improved.

Referring to fig. 10, fig. 10 is a schematic diagram of another signal transceiving method for power line communication according to an embodiment of the present application. As shown in fig. 10, the signal transceiving method is applied to a signal transceiving circuit for power line communication, which includes a differential mode coupling circuit, a common mode coupling circuit, and a noise processing circuit. The differential mode coupling circuit comprises a fourth coupling transformer, a fourth transceiving circuit, a fifth coupling transformer and a fifth transceiving circuit, and the common mode coupling circuit comprises a common mode transformer and a common mode signal receiving circuit. The fourth coupling transformer is connected to the live line and the neutral line, and the fourth coupling transformer is coupled to the fourth transceiving circuit. The fifth coupling transformer is connected with the live wire, the zero wire and the ground wire, and the fifth coupling transformer is coupled to the fifth transceiving circuit. The common mode transformer is connected with the live wire, the zero wire and the ground wire, and the common mode transformer is coupled to the common mode signal receiving circuit. The noise processing circuit comprises an analog interface, an analog front end, a digital interface and a digital front end, wherein the analog front end is connected with the differential mode coupling circuit and the common mode coupling circuit through the analog interface, the digital front end is connected with the analog front end through the digital interface, and the analog front end comprises an adjustable amplifier and an analog-to-digital converter. The signal transceiving method comprises steps S1001-S1011, and specifically comprises the following steps:

and S1001, the fourth differential mode signal received from the live wire and the zero wire is coupled to a fourth transceiving circuit by the fourth coupling transformer.

And S1002, the fourth transceiver circuit receives a fourth differential-mode signal which is coupled to the fourth transceiver circuit by the fourth coupling transformer.

And S1003, the fifth coupling transformer couples the fifth differential mode signals received from the live wire, the zero wire and the ground wire to the fifth transceiver circuit.

And the fifth differential mode signal is a differential mode signal formed by a common mode signal on the live wire and the zero wire and the ground wire.

And S1004, the fifth transceiver circuit receives a fifth differential-mode signal which is coupled to the fifth transceiver circuit by the fifth coupling transformer.

And S1005, coupling the common-mode signals received from the live wire, the zero wire and the ground wire to a common-mode signal receiving circuit by using the common-mode transformer.

S1006, the common mode signal receiving circuit receives the common mode signal coupled to the common mode signal receiving circuit by the common mode transformer.

S1007, the analog interface receives the fourth differential mode signal, the fifth differential mode signal and the common mode signal.

And S1008, amplifying the fourth differential mode signal, the fifth differential mode signal and the common mode signal received by the analog interface by the adjustable amplifier to obtain an amplified differential mode signal and an amplified common mode signal.

S1009, the analog-to-digital converter samples the amplified differential-mode signal and common-mode signal to obtain a digital signal.

And S1010, receiving the digital signal by the digital interface.

And S1011, the digital front end processes the digital signal received by the digital interface so as to eliminate noise.

In the above-mentioned signal transceiving method, because various electrical appliances are added on the power line, the signal transmitted on the power line includes electrical appliance noise, that is, the two coupled and received differential mode signals both include differential mode electrical appliance noise. Meanwhile, the electrical noise has strong common-mode characteristics, so that the coupled and received common-mode signal comprises the common-mode electrical noise. Because the electrical appliance noise in the two paths of differential mode signals has correlation with the common-mode electrical appliance noise, the electrical appliance noise can be eliminated by processing the received digital signals through a digital end algorithm, so that the performance of power line communication is improved.

Referring to fig. 11, fig. 11 is a schematic diagram of performance gain achieved by receiving signals through the signal transceiver circuit provided in the embodiment of the present application. As shown in fig. 11, the white histogram is a schematic diagram of performance gain achieved by receiving three signals through a conventional T-type coupling circuit, and the black histogram is a schematic diagram of performance gain achieved by introducing a common mode coupling circuit to receive three signals (including one common mode signal) based on the T-type coupling circuit according to the embodiment of the present application. The line graph is a schematic diagram of performance gain achieved by comparing signals received by the signal transceiver circuit provided by the embodiment of the present application with signals received by a conventional circuit, and it can be seen that, under interference of various electrical appliance noises, performance improvement of 5-78% can be achieved by receiving signals by the signal transceiver circuit provided by the embodiment of the present application.

The foregoing detailed description of the embodiments of the present application has been presented to illustrate the principles and implementations of the present application, and the above description of the embodiments is only provided to help understand the method and the core concept of the present application; meanwhile, for a person skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in view of the above, the content of the present specification should not be construed as a limitation to the present application.

Claims

A signal transceiver circuit for power line communication, the circuit comprising a differential mode coupling circuit, a common mode coupling circuit and a noise processing circuit, the differential mode coupling circuit and the common mode coupling circuit being respectively connected to a power line, the noise processing circuit being connected to the differential mode coupling circuit and the common mode coupling circuit, the power line comprising at least one of: a live line, a neutral line, and a ground line, wherein,

the differential mode coupling circuit is used for coupling and receiving a differential mode signal on the power line;

the common mode coupling circuit is used for coupling and receiving a common mode signal on the power line;

the noise processing circuit is used for processing the common mode signal and the differential mode signal so as to eliminate noise in the differential mode signal.
The circuit of claim 1, wherein the differential mode coupling circuit comprises at least one coupling transformer and at least one transceiver circuit, each of the at least one coupling transformer being connected to at least two of the power lines, each of the at least one coupling transformer being coupled to one of the at least one transceiver circuit, wherein,

each of the at least one coupling transformer for coupling differential mode signals received from at least two of the power lines to one of the at least one transceiver circuit;

each of the at least one transceiver circuit for receiving the differential mode signal that the each coupling transformer is coupled to.
The circuit of claim 1 or 2, wherein the common-mode coupling circuit comprises a common-mode transformer and a common-mode signal receiving circuit, the common-mode transformer being connected to hot, neutral and ground lines, the common-mode transformer being coupled to the common-mode signal receiving circuit, wherein,

the common mode transformer is used for coupling common mode signals received from the live wire, the zero wire and the ground wire to the common mode signal receiving circuit;

the common mode signal receiving circuit is used for receiving the common mode signal which is coupled to the common mode signal receiving circuit by the common mode transformer.
The circuit of any of claims 1 to 3, wherein the differential mode coupling circuit comprises a first coupling transformer connected to two lines of the power line, a first transceiving circuit coupled to the first coupling transformer, a second coupling transformer connected to two lines of the power line, and a second transceiving circuit coupled to the second transceiving circuit, wherein the two lines of the power line connected to the first coupling transformer are two lines of a hot line, a neutral line, and a ground line, and wherein the two lines of the power line connected to the first coupling transformer are different from the two lines of the power line connected to the second coupling transformer, wherein,

the first coupling transformer is used for coupling first differential mode signals received from two lines in the power line to the first transceiving circuit;

the first transceiver circuitry is configured to receive the first differential-mode signal coupled to the first transceiver circuitry by the first coupling transformer;

the second coupling transformer is configured to couple a second differential-mode signal received from two of the power lines to the second transceiver circuit;

the second transceiver circuit is configured to receive the second differential-mode signal coupled to the second transceiver circuit by the second coupling transformer.
The circuit of claim 4, wherein the differential mode coupling circuit further comprises a third coupling transformer and a third transceiving circuit, the third coupling transformer being connected to two of the power lines, the third coupling transformer being coupled to the third transceiving circuit, the two of the power lines to which the third coupling transformer is connected being different from the two of the power lines to which the first coupling transformer is connected and being different from the two of the power lines to which the second coupling transformer is connected, wherein,

the third coupling transformer is configured to couple a third differential-mode signal received from two of the power lines to the third transceiver circuit;

the third transceiver circuit is configured to receive the third differential-mode signal coupled to the third transceiver circuit by the third coupling transformer.
The circuit according to any of claims 1 to 3, wherein the differential mode coupling circuit comprises a fourth coupling transformer connected to at least two lines of the power line, a fourth transceiving circuit, a fifth coupling transformer coupled to the fourth transceiving circuit, and a fifth transceiving circuit, the fifth coupling transformer connected to at least two lines of the power line, the fifth coupling transformer coupled to the fifth transceiving circuit, the at least two lines of the power line being two of the hot line, the neutral line and the ground line or the hot line, the neutral line and the ground line, at least one of the fourth coupling transformer and the fifth coupling transformer being connected to the hot line, the neutral line and the ground line, wherein,

the fourth coupling transformer is configured to couple a fourth differential-mode signal received from at least two of the power lines to the fourth transceiver circuit;

the fourth transceiving circuitry to receive the fourth differential-mode signal that the fourth coupling transformer is coupled to the fourth transceiving circuitry;

the fifth coupling transformer is configured to couple a fifth differential-mode signal received from at least two of the power lines to the fifth transceiver circuit;

the fifth transceiver circuit is configured to receive the fifth differential-mode signal coupled to the fifth transceiver circuit by the fifth coupling transformer.
The circuit of claim 6, wherein the differential mode coupling circuit further comprises a sixth coupling transformer and a sixth transceiving circuit, the sixth coupling transformer connected with at least two of the power lines, the sixth coupling transformer coupled to the sixth transceiving circuit, wherein,

the sixth coupling transformer is configured to couple sixth differential-mode signals received from at least two of the power lines to the sixth transceiver circuit;

the sixth transceiving circuitry to receive the sixth differential mode signal that the sixth coupling transformer is coupled to the sixth transceiving circuitry.
The circuit according to any of claims 1 to 7, wherein the noise processing circuit comprises an analog interface, an analog front end, a digital interface, and a digital front end, the analog front end being connected to the differential mode coupling circuit and the common mode coupling circuit via the analog interface, the digital front end being connected to the analog front end via the digital interface, the analog front end comprising a tunable amplifier and an analog-to-digital converter, wherein,

the analog interface is used for receiving the differential mode signal and the common mode signal;

the adjustable amplifier is used for amplifying the differential mode signal and the common mode signal received by the analog interface to obtain an amplified differential mode signal and an amplified common mode signal;

the analog-to-digital converter is used for sampling the amplified differential mode signal and the amplified common mode signal to obtain a digital signal;

the digital interface is used for receiving the digital signal;

the digital front end is used for processing the digital signals received by the digital interface so as to eliminate noise.
A signal transceiving method for power line communication, wherein the signal transceiving circuit is applied to power line communication, the signal transceiving circuit comprises a differential mode coupling circuit, a common mode coupling circuit and a noise processing circuit, the differential mode coupling circuit and the common mode coupling circuit are respectively connected to a power line, the noise processing circuit is connected to the differential mode coupling circuit and the common mode coupling circuit, and the power line includes at least one of: a live wire, a neutral wire, and a ground wire, the method comprising:

the differential mode coupling circuit is used for coupling and receiving a differential mode signal on the power line;

the common mode coupling circuit is coupled with and receives a common mode signal on the power line;

the noise processing circuit processes the common mode signal and the differential mode signal to eliminate noise in the differential mode signal.
The method of claim 9, wherein the differential-mode coupling circuit comprises at least one coupling transformer and at least one transceiver circuit, each coupling transformer of the at least one coupling transformer being connected to at least two lines of the power line, each coupling transformer of the at least one coupling transformer being coupled to one transceiver circuit of the at least one transceiver circuit, the differential-mode coupling circuit coupling receiving differential-mode signals on the power line comprising:

each of the at least one coupling transformer couples differential mode signals received from at least two of the power lines to one of the at least one transceiver circuit;

each of the at least one transceiver circuit receives the differential mode signal that the each coupling transformer couples to the each transceiver circuit.
The method of claim 9 or 10, wherein the common-mode coupling circuit comprises a common-mode transformer and a common-mode signal receiving circuit, the common-mode transformer being connected to the hot, neutral and ground lines, the common-mode transformer being coupled to the common-mode signal receiving circuit, the common-mode coupling circuit being coupled to receive a common-mode signal on the power line comprising:

the common mode transformer couples common mode signals received from the live wire, the zero wire and the ground wire to the common mode signal receiving circuit;

the common mode signal receiving circuit receives the common mode signal that the common mode transformer is coupled to the common mode signal receiving circuit.
The method of any of claims 9 to 11, wherein the differential mode coupling circuit comprises a first coupling transformer connected to two lines of the power line, a first transceiver circuit coupled to the first transceiver circuit, a second coupling transformer connected to two lines of the power line, and a second transceiver circuit coupled to the second transceiver circuit, wherein the two lines of the power line are two of a hot line, a neutral line, and a ground line, wherein the two lines of the power line connected by the first coupling transformer are different from the two lines of the power line connected by the second coupling transformer, and wherein the differential mode coupling circuit is configured to receive the differential mode signal on the power line by coupling comprising:

the first coupling transformer couples first differential mode signals received from two of the power lines to the first transceiving circuit;

the first transceiving circuitry receives the first differential mode signal that the first coupling transformer is coupled to the first transceiving circuitry;

the second coupling transformer couples second differential mode signals received from two of the power lines to the second transceiving circuitry;

the second transceiving circuitry receives the second differential mode signal that the second coupling transformer couples to the second transceiving circuitry.
The method of claim 12, wherein the differential-mode coupling circuit further comprises a third coupling transformer and a third transceiver circuit, the third coupling transformer connected to two of the power lines, the third coupling transformer coupled to the third transceiver circuit, the two of the power lines connected by the third coupling transformer being different from the two of the power lines connected by the first coupling transformer and different from the two of the power lines connected by the second coupling transformer, the differential-mode coupling circuit coupled to receive differential-mode signals on the power lines further comprising:

the third coupling transformer couples third differential mode signals received from two of the power lines to the third transceiving circuit;

the third transceiving circuitry receives the third differential mode signal that the third coupling transformer is coupled to the third transceiving circuitry.
The method of any of claims 9 to 11, wherein the differential mode coupling circuit comprises a fourth coupling transformer, a fourth transceiving circuit, a fifth coupling transformer, and a fifth transceiving circuit, the fourth coupling transformer is connected to at least two lines of the power line, the fourth coupling transformer is coupled to the fourth transceiving circuit, the fifth coupling transformer is connected with at least two lines of the power lines, the fifth coupling transformer is coupled to the fifth transceiving circuit, at least two wires in the power line are two wires of a live wire, a zero wire and a ground wire or the live wire, the zero wire and the ground wire, at least one of the fourth coupling transformer and the fifth coupling transformer is connected with the live wire, the zero wire and the ground wire, and the differential mode coupling circuit is coupled to receive the differential mode signal on the power line and comprises:

the fourth coupling transformer couples fourth differential mode signals received from at least two of the power lines to the fourth transceiving circuitry;

the fourth transceiving circuitry receives the fourth differential mode signal that the fourth coupling transformer is coupled to the fourth transceiving circuitry;

the fifth coupling transformer couples fifth differential mode signals received from at least two of the power lines to the fifth transceiving circuitry;

the fifth transceiving circuitry receives the fifth differential mode signal that the fifth coupling transformer is coupled to the fifth transceiving circuitry.
The method of claim 14, wherein the differential-mode coupling circuit further comprises a sixth coupling transformer and a sixth transceiving circuit, the sixth coupling transformer connected to at least two lines of the power line, the sixth coupling transformer coupled to the sixth transceiving circuit, the differential-mode coupling circuit coupled to receive differential-mode signals on the power line further comprising:

the sixth coupling transformer couples sixth differential mode signals received from at least two of the power lines to the sixth transceiving circuitry;

the sixth transceiving circuitry receives the sixth differential mode signal that the sixth coupling transformer is coupled to the sixth transceiving circuitry.
The method of any of claims 9 to 15, wherein the noise processing circuit comprises an analog interface, an analog front end, a digital interface, and a digital front end, the analog front end is connected to the differential-mode coupling circuit and the common-mode coupling circuit through the analog interface, the digital front end is connected to the analog front end through the digital interface, the analog front end comprises a tunable amplifier and an analog-to-digital converter, and the noise processing circuit processes the common-mode signal and the differential-mode signal to remove noise in the differential-mode signal comprises:

the analog interface receives the differential mode signal and the common mode signal;

the adjustable amplifier amplifies the differential mode signal and the common mode signal received by the analog interface to obtain an amplified differential mode signal and an amplified common mode signal;

the analog-to-digital converter samples the amplified differential mode signal and the amplified common mode signal to obtain a digital signal;

the digital interface receives the digital signal;

and the digital front end processes the digital signal received by the digital interface so as to eliminate noise.