CN114830546B

CN114830546B - Signal receiving and transmitting circuit and method for power line communication

Info

Publication number: CN114830546B
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: 2023-12-08
Anticipated expiration: 2039-12-30
Also published as: WO2021134379A1; CN114830546A

Abstract

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

Description

Signal receiving and transmitting circuit and method for power line communication

Technical Field

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

Background

Power line communication (power line communication, PLC) technology refers to a communication scheme that utilizes power lines to transmit data and media signals.

Noise in power line communication mainly originates from electric appliances in a power line network, and load impedance of various electric appliances added on the power line network changes in real time, and noise interference also changes in real time. The electric appliance noise in the power line communication generally appears as various forms of impulse noise, and the impulse amplitude is large, deteriorating the performance of the power line communication. It is common today to utilize the periodic nature of the appliance noise to communicate at different time periods using the channel carrying capacity of that time period. However, the power line communication is poor in performance because the power line communication is only carried out by matching the channel carrying capacity under the existing noise condition without improving the noise of the electric appliance.

Disclosure of Invention

The embodiment of the application provides a signal transceiving circuit and a signal transceiving method for power line communication, which are characterized in that 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 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 transceiver 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, and 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 signal on the power line is obtained by introducing the common mode coupling circuit, and the noise in the differential mode signal obtained by the differential mode coupling circuit has correlation with the noise in the common mode signal, so that 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, 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 of the at least one coupling transformer is connected with at least two lines in the power line, each of the at least one coupling transformer is coupled to one transceiver circuit in the at least one transceiver circuit, wherein each of the at least one coupling transformer is configured to couple a differential mode signal received from at least two lines in the power line to one transceiver circuit in the at least one transceiver circuit; each of the at least one transceiver circuit is configured to receive the differential mode signal coupled to the each transceiver circuit by the each coupling transformer.

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 with a live wire, a neutral wire and a ground wire, and the common mode transformer is coupled to the common mode signal receiving circuit, wherein the common mode transformer is used for coupling 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 configured to receive the common mode signal of the common mode transformer coupled to the common mode signal receiving circuit.

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 transceiver circuit, a second coupling transformer and a second transceiver circuit, where the first coupling transformer is connected to two lines of the power lines, the first coupling transformer is coupled to the first transceiver circuit, the second coupling transformer is connected to two lines of the power lines, the second coupling transformer is coupled to the second transceiver circuit, the two lines of the power lines are two lines of a live line, a neutral line and a ground line, the two lines of the power lines connected by the first coupling transformer are different from the two lines of the power lines connected by the second coupling transformer, and the first coupling transformer is used to couple the first differential mode signal received from the two lines of the power lines to the first transceiver circuit; the first transceiver circuit is configured to receive the first differential mode signal coupled to the first transceiver circuit by the first coupling transformer; the second coupling transformer is used for coupling second differential mode signals received from two lines 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 transceiver circuit, the third coupling transformer is connected with two lines of the power lines, the third coupling transformer is coupled to the third transceiver circuit, the two lines of the power lines connected by the third coupling transformer are different from the two lines of the power lines connected by the first coupling transformer, and the two lines of the power lines connected by the second coupling transformer are different from each other, wherein the third coupling transformer is configured to couple a third differential mode signal received from the two lines 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.

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 transceiver circuit, a fifth coupling transformer and a fifth transceiver circuit, where the fourth coupling transformer is connected to at least two lines of the power line, the fourth coupling transformer is coupled to the fourth transceiver circuit, the fifth coupling transformer is connected to at least two lines of the power line, the fifth coupling transformer is coupled to the fifth transceiver circuit, at least two lines of the power line are two lines of a live line, a neutral line and a ground line, or a live line, a neutral line and a ground line, and at least one of the fourth coupling transformer and the fifth coupling transformer is connected to a live line, a neutral line and a ground line, and the fourth coupling transformer is used to couple a fourth differential mode signal received from at least two lines of the power line to the fourth transceiver circuit; the fourth transceiver circuit is configured to receive the fourth differential mode signal coupled to the fourth transceiver circuit by the fourth coupling transformer; the fifth coupling transformer is configured to couple a fifth differential mode signal received from at least two lines 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 transceiver circuit, the sixth coupling transformer is connected with at least two lines of the power line, the sixth coupling transformer is coupled to the sixth transceiver circuit, wherein 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 transceiver circuit; the sixth transceiver circuit is configured to receive the sixth differential mode signal coupled to the sixth transceiver circuit by the sixth coupling transformer.

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, and 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 a common mode signal; the analog-to-digital converter is used for sampling the amplified differential mode signal and the 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, 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 hot, neutral and 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 to receive 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 the noise in the differential mode signal obtained by the differential mode coupling circuit has correlation with the noise in the common mode signal, so that the noise in the differential mode signal and the common mode signal can be processed by the noise processing circuit to eliminate the noise in the received signal, thereby improving the performance of power line communication.

With reference to the second aspect, in one 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 with 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 coupling the differential mode signal received on the power line includes: 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 is coupled 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 with a live wire, a neutral wire and a 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 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 of the common mode transformer coupled to the common mode signal receiving circuit.

With reference to the second aspect, in one 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, where 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 lines 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 coupling receives a differential mode signal on the power line includes: the first coupling transformer couples first differential mode signals received from two of the power lines to the first transceiver circuit; the first transceiver circuit receives the first differential mode signal coupled to the first transceiver circuit by the first coupling transformer; the second coupling transformer couples second differential mode signals received from two of the power lines to the second transceiver circuit; the second transceiver circuit receives the second differential mode signal coupled to the second transceiver circuit by the second coupling transformer.

With reference to the second aspect, in one 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 with two lines of the power lines, the third coupling transformer is coupled to the third transceiver circuit, the two lines of the power lines connected by the third coupling transformer are different from the two lines of the power lines connected by the first coupling transformer, and the two lines of the power lines connected by the second coupling transformer are different, and the differential mode coupling circuit coupling receives the differential mode signal on the power lines further includes: the third coupling transformer couples a third differential mode signal received from two of the power lines to the third transceiver circuit; the third transceiver circuit receives the third differential mode signal coupled to the third transceiver circuit by the third coupling transformer.

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 transceiver circuit, a fifth coupling transformer, and a fifth transceiver circuit, where the fourth coupling transformer is connected to at least two lines of the power line, the fourth coupling transformer is coupled to the fourth transceiver circuit, the fifth coupling transformer is connected to at least two lines of the power line, the fifth coupling transformer is coupled to the fifth transceiver circuit, at least two lines of the power line are two lines of a live line, a neutral line, and a ground line, or a live line, a neutral line, and a ground line, at least one of the fourth coupling transformer and the fifth coupling transformer is connected to a live line, a neutral line, and a ground line, and the differential mode coupling circuit coupling receives a differential mode signal on the power line includes: the fourth coupling transformer couples fourth differential mode signals received from at least two of the power lines to the fourth transceiver circuit; the fourth transceiver circuit receives the fourth differential mode signal coupled to the fourth transceiver circuit by the fourth coupling transformer; the fifth coupling transformer couples fifth differential mode signals received from at least two of the power lines to the fifth transceiving circuit; the fifth transceiver circuit receives the fifth differential mode signal coupled to the fifth transceiver circuit by the fifth coupling transformer.

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 transceiver circuit, the sixth coupling transformer is connected with at least two lines of the power line, the sixth coupling transformer is coupled to the sixth transceiver circuit, and the differential mode coupling circuit is coupled to receive the differential mode signal on the power line further includes: the sixth coupling transformer couples a sixth differential mode signal received from at least two of the power lines to the sixth transceiver circuit; the sixth transceiver circuit receives the sixth differential mode signal coupled to the sixth transceiver circuit by the sixth coupling transformer.

With reference to the second aspect, in one 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 a common mode signal; the analog-to-digital converter samples the amplified differential mode signal and the common mode signal to obtain a digital signal; the digital interface receives the digital signal; the digital front end processes the digital signals received by the digital interface 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 Delixiviation lamp during an AC period;

FIG. 1e is a schematic diagram of a received signal under interference from a Delixiviation lamp;

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

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

FIG. 3 is a schematic 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 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 according to 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 comprised by the electronic device 4 in fig. 5 a;

FIG. 5c is a schematic diagram of another differential mode coupling circuit 4 and 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 application;

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

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

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

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

fig. 11 is a schematic diagram of performance gain achieved by receiving signals by the signal transceiver circuit according to the 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 accompanying drawings in the embodiments of the present application.

In the following, some terms in the embodiments of the present application are explained for easy understanding by those skilled in the art.

Reference to "at least one" in embodiments of the application means one or more, and "plurality" means two or more. "and/or", describes an association relationship of an association object, and indicates that there may be three relationships, for example, a and/or B, and may indicate: a alone, a and B together, and B alone, wherein a, B may be singular or plural. The character "/" generally indicates that the context-dependent object is an "or" relationship. "at least one of" or the like means any combination of these items, including any combination of single item(s) or plural items(s). 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 plural.

And, unless specified to the contrary, references to "first," "second," etc. ordinal words of embodiments of the present application are used for distinguishing between multiple objects and are not used for limiting the order, timing, priority, or importance of the multiple objects. For example, the first information and the second information are only for distinguishing different information, and are not indicative of the difference in content, priority, transmission order, importance, or the like of the two information.

In order to facilitate understanding of the present application, the background art of the application is first described herein:

power line communication: power line communication (power line communication, PLC) technology refers to a communication scheme that utilizes power lines to transmit data and media signals, also known as a power line network. PLC technology uses existing low frequency (50/60 hz) power lines to transmit broadband data. Digital subscriber line (digital subscriber line, DSL) technology uses telephone lines for data transmission, cable Modems (CM) use cable television coaxial lines for data transmission, relatively speaking, power line communication technology is used without substantial additional re-wiring of network lines, and power lines cover a wider area than other carriers.

The broadband technology of the power line communication mainly comprises an IEEE Homeplug AV and an ITU-T G.hn at present, and both technologies adopt an orthogonal frequency division multiplexing (orthogonal frequency division multiplexing, OFDM) modulation mode, wherein the orthogonal frequency division multiplexing modulation mode is beneficial to ensuring stable and complete transmission of data in a severe electromagnetic interference communication environment.

The power line communication has the advantages that the coverage range of the power line is wide, and the power line naturally covers households 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 put on the design of a transceiver. The power line communication is most affected by various electrical loads added on the power line, and time-varying load impedance changes and time-varying noise changes are introduced.

Electric cat: a modem, i.e., a power line communication modem, is a modem that performs broadband internet access via a power line. A personal computer (personal computer, PC), broadband internet appliance (e.g., asymmetric subscriber digital loop modem (asymmetric digital subscriber line modem, ADSL modem)), set top box, audio appliance, monitoring appliance, and other intelligent electrical appliances are connected to transmit data, voice, and video using a home or office existing power line and outlet assembly. The electric cat has the characteristics of plug and play, and can transmit network IP digital signals through a common home power line.

Power line multiple input multiple output technique: the multiple-input multiple-output (MIMO) technology refers to a technology for performing multiple-input multiple-output communication by three lines, i.e., power line fire (L), zero (N), and earth (PE). In the power line multiple input multiple output technology, three lines of the power line can form two paths of signals, and a mode of two-transmission and two-transmission (2T 2R) or two-transmission and three-transmission (2T 3R) is generally adopted during signal receiving and transmitting. Currently, a Delta-type coupling circuit or a T-type coupling circuit is 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 receiving and transmitting terminals D1, D2 and D3, wherein the three signal receiving and transmitting terminals D1, D2 and D3 are respectively used for transmitting or receiving signals, and the Delta-type differential mode coupling circuit further includes coupling transformers C1, C2 and C3, wherein the coupling transformers are used for coupling differential mode signals transmitted by the signal receiving and transmitting terminals to a power line or coupling differential mode signals received from the power line to the signal receiving and transmitting terminals. When a 2T2R signal receiving and transmitting mode is adopted, two signal receiving and transmitting ends of D1, D2 and D3 are adopted to transmit or receive signals. For example, D1 and D2 are used for signal transceiving, when D1 is used for transmitting signals, C1 is connected with the live wire and the neutral wire, and C1 is coupled to D1, the 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 can be transmitted through the live wire and the neutral wire; when the D2 is adopted to send signals, C2 is connected with a fire wire and a ground wire, C2 is coupled to D2, differential mode signals sent by D2 can be coupled to the fire wire and the ground wire through C2, and then the differential mode signals are sent through the fire wire and the ground wire; when D1 is used to receive the signal, the differential mode signals on the hot and neutral wires may be coupled to D1 through C1, and then D1 receives the differential mode signals on the hot and neutral wires; when D2 is used to receive the signal, the differential mode signals on the hot and ground lines may be coupled to D2 through C2, and then D2 receives the differential mode signals on the hot and ground lines. When adopting the 2T3R signal receiving and transmitting mode, two or three of the signal receiving and transmitting ends in D1, D2 and D3 are adopted to transmit signals. For example, D1 and D2 are used for signal transmission, D1, D2 and D3 are used for signal reception, C1 is connected to the live and neutral wires when D1 is used for signal transmission, C1 is coupled to D1, and the differential mode signal transmitted by D1 can be coupled to the live and neutral wires through C1, and then the differential mode signal can be transmitted through the live and neutral wires; when the D2 is adopted to send signals, C2 is connected with a fire wire and a ground wire, C2 is coupled to D2, differential mode signals sent by D2 can be coupled to the fire wire and the ground wire through C2, and then the differential mode signals are sent through the fire wire and the ground wire; when D1 is used to receive the signal, the differential mode signals on the hot and neutral wires may be coupled to D1 through C1, and then D1 receives the differential mode signals on the hot and neutral wires; when the D2 receiving signal is adopted, the differential mode signals on the fire wire and the ground wire can be coupled to the D2 through the C2, and then the D2 receives the differential mode signals on the fire wire and the ground wire; when the D3 reception signal is employed, C3 is connected to the neutral line and the ground line, and C3 is coupled to D3, the differential mode signals on the neutral line and the ground line may be coupled to D3 through C3, and then D3 receives the differential mode signals on the neutral line and the ground line.

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 receiving and transmitting terminals T1 and T2, wherein the T1 and T2 are respectively used for transmitting or receiving signals, and the T-type differential mode coupling circuit further includes coupling transformers C4 and C5 for coupling differential mode signals transmitted from the signal receiving and transmitting terminals to the power line or for coupling differential mode signals received from the power line to the signal receiving and transmitting terminals. When a 2T2R signal transmission and reception method is adopted, T1 and T2 are adopted for signal transmission and reception. When T1 is adopted to send signals, C4 is connected with the live wire and the zero wire, C4 is coupled to T1, differential mode signals sent by T1 can be coupled to the live wire and the zero wire through C4, and then the differential mode signals are sent through the live wire and the zero wire; when T2 is adopted to send signals, C5 is connected with a live wire, a neutral wire and a ground wire, C5 is coupled to T2, and differential mode signals sent by T2 can be coupled to the live wire, the neutral wire and the ground wire through C5, and then differential mode signals (common mode signals of the live wire and the neutral wire and differential mode signals formed by the common mode signals of the live wire and the neutral wire and the ground wire) are sent through the live wire, the neutral wire and the ground wire; when T1 is adopted to receive signals, differential mode signals on a live wire and a zero wire can be coupled to T1 through C4, and then T1 receives the differential mode signals on the live wire and the zero wire; when T2 is used to receive signals, differential mode signals on the live, neutral and ground lines (common mode signals on the live and neutral lines, and differential mode signals consisting of ground) may be coupled to T2 through C5, and then T2 receives differential mode signals on the live, neutral and ground lines. When adopting the signal receiving and transmitting mode of 2T3R, this T type differential mode coupling circuit includes three signal receiving and transmitting ends, adopts wherein two signal receiving and transmitting ends to send the signal or adopts three signal receiving and transmitting ends to receive the signal. When two of the signal receiving and transmitting terminals are used to transmit signals, reference may be made to the above-described transmission of signals through T1 and T2; when three signal receiving and transmitting ends are adopted to receive signals, two signal receiving and transmitting ends can refer to the signals received through T1 and T2, and the other signal receiving and transmitting end can receive differential mode signals on a live wire and a ground wire or differential mode signals on a zero wire and the ground wire.

Electric appliance noise: electrical noise is one of the main noises in power line communication, and is generally presented as impulse noise in various forms, and the amplitude of part of electrical noise is large, resulting in a great influence on the performance of power line communication. Meanwhile, the electrical noise has rich frequency characteristics, and the real-time change of the noise of most electrical noise in the power line system has the periodic characteristic which is matched with the alternating current (alternate 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 periodic variation of alternating current. 1c-2 is a schematic diagram of the channel response of different frequencies over time, the real-time variation of the channel response having a periodic characteristic that coincides with the alternating current period. 1c-3 is a schematic diagram of the variation of noise with time, the real-time variation of noise having a periodic characteristic matching the alternating current period.

The variety of electric appliances and models in actual families and working environments causes the diversity of noise characteristics in the power line system. In addition, noise generated by the same electric appliance has inconsistent noise characteristics in the power line period, 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 noise generated by the deluxe spotlight varying in an ac cycle. Wherein 1d-1, 1d-2 and 1d-3 are schematic diagrams of the variation of noise generated by the Delixiviation lamp 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 interference of a deluxe spotlight. As shown in fig. 1e, the received signal acquired at 40dB attenuation is greatly affected by noise generated by the deluxe lamp, and thus affects demodulation performance.

Having described the background of the application as above, 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 transceiver circuit for power line communication according to an embodiment of the present application. 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 electronic equipment, and the electronic equipment can be, for example, a power cat.

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

The differential mode coupling circuit 201 is used for coupling differential mode signals on the receiving power line. Wherein the differential mode signal on the power line comprises differential mode signals on two lines of the power line or differential mode signals on three lines of the power line. The differential mode signals on the two lines in the power line include differential mode signals on the live and neutral lines, differential mode signals on the live and ground lines, or differential mode signals on the neutral and ground lines. The differential mode signals on the three lines of the power line comprise differential mode signals formed by common mode signals on a live line and a zero line and a 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 comprises at least one coupling transformer and at least one transceiving circuit, wherein each of the at least one coupling transformer is connected to at least two of the power lines and is coupled to one of the at least one transceiving circuit. Each coupling transformer is configured to couple a differential mode signal 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 being configured to receive the differential mode signal coupled to each transceiver circuit by the each coupling transformer.

The common mode coupling circuit 202 is used for coupling the common mode signal on the receiving power line. The common mode signals on the power line are common mode signals on the live line, the zero line and the ground line.

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 hot, neutral and ground lines, 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 of the common mode transformer coupled to the common mode signal receiving circuit.

And a noise processing circuit 203 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, since various electric appliances are added to the power line, the electric appliance noise is included in the signal transmitted on the power line, the differential mode signal (including the electric appliance noise of the differential mode) on the power line can be obtained by coupling through the differential mode coupling circuit 201, and meanwhile, the common mode signal (including the electric appliance noise of the common mode) on the power line can be obtained by introducing the common mode coupling circuit 202 because the electric appliance noise has a strong common mode characteristic. Since 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, 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, thereby improving the performance of the power line communication.

Wherein the correlation of the electrical noise of the differential mode and the electrical noise of the common mode is seen in fig. 2b. As shown in fig. 2b, 2b-1 is a schematic diagram of time domain noise collected through a differential mode path and a common mode path, wherein a solid line is a schematic diagram of electrical noise of a differential mode received through a differential mode coupling circuit, and a dotted line is a schematic diagram of electrical noise of a common mode received through a common mode coupling circuit. 2b-2 is a schematic diagram of correlation coefficients of the electrical noise of the differential mode and the electrical noise of the common mode, it can be seen that the correlation operation is performed on the electrical noise of the differential mode and the electrical noise of the common mode, and it can be seen that the electrical noise of the differential mode and the electrical noise of the common mode have stronger correlation.

The working principle of the common-mode transformer (common-mode transformer) of fig. 2a is specifically described 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 power lines. For example, the live wire is connected with the port 1 and the port 2, and a signal on the live wire is input into the common mode transformer through the port 1 and output through the port 2; the zero line is connected with the port 3 and the port 4, and signals on the zero line are input into the common mode transformer through the port 3 and output through the port 4; the ground wire is connected with the port 5 and the port 6, and a signal on the ground wire is input into the common mode transformer through the port 5 and output through the port 6. The coil A, the coil B, the coil C and the coil D are wound on a 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 inductance at the moment, magnetic fields generated by the differential mode signals cancel each other, and the differential mode signal can pass through a differential mode signal output port basically without attenuation; when the common mode signal flows through the common mode transformer, the magnetic fields generated by the common mode signal are mutually enhanced, at the moment, the coil A, the coil B and the coil C show high impedance for the differential mode signal output port, the differential mode signal output port has stronger attenuation effect on the common mode signal, and the coil D senses the magnetic flux of the common mode signal for the common mode signal output port, so that induced electromotive force is generated and passes through the common mode signal output port. Therefore, when the signal on the power line is input to the common mode transformer through the ports 1, 3 and 5, and output through the ports 2, 4 and 6, the differential mode signal loss is small, and the common mode signal loss is large. When signals on the power line are input into the common mode transformer through the port 1, the port 3 and the port 5 and 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 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 application. As shown in fig. 4a, a common mode coupling circuit is introduced as a third receiving path based on a Delta type differential mode coupling circuit and 2T 2R. On the signal transmitting side, a signal is transmitted through the electronic device 1, and the electronic device 1 includes a differential mode coupling circuit 1. Specifically, the differential mode signals are transmitted by the first transceiver circuit and the second transceiver circuit of the differential mode coupling circuit 1, the differential mode signals are coupled to the power line through the differential mode coupling circuit 1, so that the differential mode signals are transmitted by the live wire and the zero wire, the differential mode signals are transmitted by the live wire and the ground wire, and then the signals transmitted 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, and the electronic device 2 includes a differential mode coupling circuit 2 and a common mode coupling circuit. Specifically, signals on three lines of the power line are coupled out through a common mode transformer, the common mode transformer receives common mode signals on a live line, a zero line and a ground line 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, the differential mode signals on the power line are coupled to a first transceiver circuit and a second transceiver circuit of the differential mode coupling circuit 2, and the first transceiver circuit and the second transceiver circuit of the differential mode coupling circuit 2 receive the differential mode signals, so that the differential mode signals on the live line and the zero line are received, and the differential mode signals on the live line and the ground line 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 TX0 of the first transceiver circuit 402 is used for transmitting signals, and an output RX0 of the first transceiver circuit 402 is used for receiving signals. The second coupling transformer 403 is connected to the live wire and the ground wire, the second coupling transformer 403 is coupled to the second transceiver circuit 404, an input TX1 of the second transceiver circuit 404 is used for transmitting signals, and an output RX1 of the second transceiver circuit 404 is used for receiving signals. The common mode transformer 405 is connected to the live, neutral and ground wires, and the common mode transformer 405 is coupled to a common mode signal receiving circuit 406, and an output RX2 of the common mode signal receiving circuit 406 is used for receiving signals.

Specifically, when receiving a signal on the power line, the signals on the live and neutral lines are input to the first coupling transformer 401, the first coupling transformer 401 couples the first differential mode signal received from the live and neutral lines to the first transceiver circuit 402, and receives the first differential mode signal through the output terminal RX0 of the first transceiver circuit 402. The signals on the live and ground lines are input to a second coupling transformer 403, which second coupling transformer 403 couples the second differential mode signal received from the live and ground lines to a 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 live, neutral and ground are input to a common mode transformer 405, respectively, the common mode transformer 405 couples the common mode signals received from the live, neutral and ground to a common mode signal receiving circuit 406 and receives the common mode signals 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, the second differential mode signal is received through the output terminal RX1 of the second transceiver circuit 404, and since various electric appliances are added to the power line, the electric 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 the electric appliance noise of the differential mode. Meanwhile, since the electrical noise has a strong common mode characteristic, a common mode signal (including 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 through 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 have correlation with the electrical noise of the common mode, the three received signals (the first differential mode signal, the second differential mode signal and the common mode signal) can be processed through a digital end algorithm subsequently so as to eliminate the electrical noise in the differential mode signals, thereby improving the performance of power line communication.

In one possible example, the differential mode coupling circuit 2 further comprises a third coupling transformer 407 and a third transceiver circuit 408, and a schematic diagram of the differential mode coupling circuit 2 and the common mode coupling circuit is shown in fig. 4 c. The third coupling transformer 407 is connected to the zero line and the ground line, the third coupling transformer 407 is coupled to the third transceiver circuit 408, and an output RX3 of the third transceiver circuit 408 is used for receiving signals.

Specifically, the signals on the neutral line and the ground line are input to the third coupling transformer 407, and the third coupling transformer 407 couples the third differential mode signal received from the neutral line and the ground line to the third transceiver circuit 408, and receives the third differential mode signal through the output terminal RX3 of the third transceiver circuit 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 electric appliances are added to the power line, the electric appliance noise is included in the signals 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 the electric appliance noise of the differential mode. Meanwhile, since the electrical noise has a strong common mode characteristic, a common mode signal (including 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 through 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 have correlation with the electrical noise of 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 through a digital end algorithm subsequently so as to eliminate the electrical noise in the differential mode signals, thereby improving the performance of power line communication.

Referring to fig. 5a, fig. 5a is a schematic diagram of another power line communication system according to an embodiment of the present application. As shown in fig. 5a, a common mode coupling circuit is introduced as a third receiving path based on a T-type differential mode coupling circuit and 2T 2R. On the signal transmitting side, a signal is transmitted through the electronic device 3, and the electronic device 3 includes a differential mode coupling circuit 3. Specifically, the fourth transceiver circuit and the fifth transceiver circuit of the differential mode coupling circuit 3 are used to transmit differential mode signals, the differential mode signals are coupled to the power line through the differential mode coupling circuit 3, so that the differential mode signals are transmitted by using the live wire and the neutral wire, the differential mode signals (the differential mode signals formed by the common mode signals on the live wire and the neutral wire and the ground wire) are transmitted by using the live wire, the neutral wire and the ground wire, 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, and the electronic device 4 includes a differential mode coupling circuit 4 and a common mode coupling circuit. Specifically, signals on three lines of the power line are coupled out through a common mode transformer, the common mode transformer receives common mode signals on a live line, a zero line and a ground line 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, the differential mode signals on the power line are coupled to a fourth transceiver circuit and a fifth transceiver circuit of the differential mode coupling circuit 4, and the fourth transceiver circuit and the fifth transceiver circuit of the differential mode coupling circuit 4 receive the differential mode signals, so that the differential mode signals on the live line and the zero line and the differential mode signals on the live line, the zero line and the ground line (the differential mode signals formed by the common mode signals on the live line and the zero line and the ground line) are received.

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 TX0 of the fourth transceiver circuit 502 is used for transmitting signals, and an output RX0 of the fourth transceiver circuit 502 is used for receiving signals. The fifth coupling transformer 503 is connected to the live wire, the neutral wire and the ground wire, the fifth coupling transformer 503 is coupled to the fifth transceiver circuit 504, the input TX1 of the fifth transceiver circuit 504 is used for transmitting signals, and the output 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, and the common mode transformer 505 is coupled to the common mode signal receiving circuit 506, and an output RX2 of the common mode signal receiving circuit 506 is used for receiving signals.

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

In the differential mode coupling circuit 4 shown in fig. 5b, the fourth differential mode signal is received through the output terminal RX0 of the fourth transceiver circuit 502, and the fifth differential mode signal is received through the output terminal RX1 of the fifth transceiver circuit 504, and since various electric appliances are added to the power line, the electric appliance noise is included in the signal transmitted on the power line, that is, the fourth differential mode signal and the fifth differential mode signal both include the electric appliance noise of the differential mode. Meanwhile, since the electrical noise has a strong common mode characteristic, a common mode signal (including common mode electrical noise) on the power line can be obtained by coupling through the introduction of the common mode transformer 505, and the common mode signal is received through 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 have correlation with the electrical noise of the common mode, the received three-way signals (the fourth differential mode signal, the fifth differential mode signal and the common mode signal) can be processed through a digital end algorithm subsequently so as to eliminate the electrical noise in the differential mode signals, thereby improving the performance of power line communication.

In a possible example, the differential mode coupling circuit 4 further comprises a sixth coupling transformer 507 and a sixth transceiver circuit 508, and a schematic diagram of the differential mode coupling circuit 4 and the common mode coupling circuit is shown in fig. 5 c. The 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 RX3 of the sixth transceiver circuit 508 is used for receiving signals.

Specifically, the signals on the live 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 live and ground lines to the sixth transceiver circuit 508, and receives the sixth differential mode signal through the output terminal RX3 of the sixth transceiver circuit 508.

In the differential mode coupling circuit 4 shown in fig. 5c, the fourth differential mode signal is received through the output terminal RX0 of the fourth transceiver circuit 502, the fifth differential mode signal is received through the output terminal RX1 of the fifth transceiver circuit 504, and the sixth differential mode signal is received through the output terminal RX3 of the sixth transceiver circuit 508, and since various electric appliances are added to the power line, the electric appliance noise is included in the signals 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 the electric appliance noise of the differential mode. Meanwhile, since the electrical noise has a strong common mode characteristic, a common mode signal (including common mode electrical noise) on the power line can be obtained by coupling through the common mode transformer 505, and the common mode signal is received through 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 have correlation with the electrical noise of 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 through a digital end algorithm subsequently so as to eliminate the electrical noise in the differential mode signals, thereby improving the performance of power line communication.

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

Wherein 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 programmable-gain amplifier 6021 and an analog-to-digital converter (analog digital converter) 6022.

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

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

A digital interface 603 for receiving the digital signal.

The digital front end 604 is configured to process the digital signal received by the digital interface 603 to eliminate noise.

Optionally, the analog interface 601 further includes a line driver (line driver), where the line driver is used to drive the signal power on the amplified line.

Alternatively, the analog front end 602 and the digital front end 604 are on the same chip, or the analog front end 602 and the digital front end 604 are on separate chips, or the analog-to-digital converter 6022 and the digital front end 604 in the analog front end 602 are on one chip, and the adjustable amplifier 6021 and the line driver in the analog front end 602 are 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 demodulation of the signal. According to the above, the common mode noise and the differential mode noise have correlation, so that the noise characteristics of the common mode signal can be utilized by a digital processing method to eliminate the electrical noise in the differential mode signal, thereby improving the performance of the power line communication. While various approaches are known in the industry to cancel noise given its characteristics, in embodiments of the present invention, the noise can be processed by a digital-side algorithm, such as a minimum mean square error-interference rejection combining (minimum mean square error-interference rejection combining, MMSE-IRC) algorithm. The MMSE-IRC algorithm is a common MIMO receiver technology, 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 offset through a specific weighting, so that the effect of suppressing the interference is achieved, that is, 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 digital front end 604 performs the following process of performing noise cancellation processing on the received signal:

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 kth carrier _r X 1-dimensional received signal, S (k) is N _t The x 1-dimensional transmission signal, N (k) is the noise plus interference on the kth carrier, S (k) is set to 0, and the variance is set to 1.

And (3) carrying out equalization processing on the received signal, and representing the equalized received signal as:

R(k)＝W(k)Y(k)＝W(k)H(k)S(k)+W(k)N(k)

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

Taking the minimum mean square error and the maximum signal to interference and noise ratio as criteria, the following are:

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 )]

＝E[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 item-by-item pair W (k) ^H And obtaining a deviation guide, namely:

W(k)E[Y(k)Y(k) ^H ]＝E[S(k)Y(k) ^H ]

the method comprises the following steps:

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

＝E[S(k)S(k) ^H H(k) ^H +S(k)N(k) ^H ]

according to S (k) mean value of 0 and variance of 1, there are:

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

covariance matrix E [ N (k) with noise ^H ]Is R _uu (k) And (3) obtaining an equalization matrix:

wherein R is _uu As a noise covariance matrix, R is defined when interference in the multipath received signals has no correlation _uu The interference rejection combining (interference rejection combining, IRC) algorithm is degenerated to the maximum ratio combining (maximal ratio combining, MRC) algorithm with the off-diagonal element of 0. The MRC algorithm corrects the phases of each path of received signals to be consistent, weights and sums the phases according to the signal to noise ratio, and the signal to noise ratio of the combined received signals is maximum, but the interference suppression effect is not achieved, and the maximum signal to interference and noise ratio cannot be achieved. The interference in the multipath signals received by the signal receiving and transmitting circuit provided by the embodiment of the application has correlation, namely R _uu And the method is a non-diagonal array, so that the received signal is processed by adopting an MMSE-IRC algorithm to achieve the maximization of signal-to-interference-plus-noise ratio, namely, the electrical noise in the received signal is eliminated.

The 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 a signal transceiver circuit for another power line communication according to an embodiment of the present application. As shown in fig. 7, the signal transceiver circuit is located on a 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 power lines, and the power lines include at least one line 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 connected to the differential mode coupling circuit 7011 and the common mode coupling circuit 7012, respectively, and are configured to receive three analog signals (including two differential mode signals and one common mode signal) obtained by 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, the first analog interface 7021 is configured to receive a first differential mode signal, and the second analog interface 7022 is configured to receive a second differential mode signal. 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 an amplification line when transmitting signals.

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 all include an adjustable amplifier and an analog-to-digital converter, where the adjustable amplifier is used to amplify an analog signal, and the analog-to-digital converter is used to sample the analog signal. The first analog front end 7031 is configured to amplify and sample a first differential mode signal received by the first analog interface 7021 to obtain a first digital signal, the second analog front end 7032 is configured to amplify and sample a second differential mode signal received by the second analog interface 7022 to obtain a second digital signal, and the third analog front end 7033 is configured to amplify and sample a third common mode signal received by the third analog interface 7023 to obtain a third digital signal.

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 digital signal obtained through the first analog front end 7031, the second digital interface 7042 is configured to receive a second digital signal obtained through the second analog front end 7032, and the third digital interface 7043 is configured to receive a third digital signal obtained through the third analog front end 7033.

The digital front end 705 is connected to the first digital interface 7041, the second digital interface 7042, and the third digital interface 7043, and the digital front end 705 includes a noise cancellation module 7051. The digital front end 705 is configured to process three digital signals received through the first digital interface 7041, the second digital interface 7042, and the third digital interface 7043, so as to implement signal receiving demodulation. The noise cancellation module 7051 is configured to perform noise cancellation processing on the received three paths of digital signals, so as to improve performance of power line communication. The noise elimination processing can be performed on the three paths of digital signals through a digital end algorithm, and the digital end algorithm can be 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 for power line communication, the 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 with a power line, the noise processing circuit is connected with the differential mode coupling circuit and the common mode coupling circuit, and the power line comprises at least one of the following: the signal receiving and transmitting method comprises the steps of S801-S803, and specifically comprises the following steps:

s801, a differential mode coupling circuit couples and receives a differential mode signal on a power line.

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

S802, the common mode coupling circuit is coupled with a common mode signal on a receiving power line.

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

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 noise of the electric appliances is included in the signal transmitted through the power line. In the signal transceiving method of the power line communication, the differential mode coupling circuit couples the received differential mode signal on the power line to comprise the electrical noise of the differential mode, and meanwhile, the common mode coupling circuit couples the received common mode signal on the power line to comprise the electrical noise of the common mode because the electrical noise has stronger common mode characteristic. The electrical noise in the differential mode signal has correlation with the electrical noise of the common mode, so that the noise processing circuit processes the common mode signal and the differential mode signal, and the electrical noise in the differential mode signal can be eliminated, thereby improving the performance of power line communication.

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 transceiver circuit, a second coupling transformer and a second transceiver 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 zero wire, and the first coupling transformer is coupled to the first transceiver circuit. The second coupling transformer is connected with the live wire and the ground wire, and is coupled to the second transceiver circuit. The common mode transformer is connected with the live wire, the zero wire and the ground wire, and 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 receiving and transmitting method comprises the steps of S901-S911, and specifically comprises the following steps:

S901, a first coupling transformer couples a first differential mode signal received from a live line and a neutral line to a first transceiver circuit.

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

S903, the second coupling transformer couples the second differential mode signal received from the live wire and the ground wire to the second transceiver circuit.

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

S905, a common mode transformer couples the common mode signals received from the live, neutral and ground wires to a common mode signal receiving circuit.

S906, the common mode signal receiving circuit receives a common mode signal of which the common mode transformer is coupled to the common mode signal receiving circuit.

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

And S908, amplifying the first differential mode signal, the second differential mode signal and the common mode signal received by the analog interface by the adjustable amplifier so as to obtain amplified differential mode signals and common mode signals.

S909, the analog-to-digital converter samples the amplified differential mode signal and the 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 to eliminate noise.

The digital signal may be specifically subjected to noise cancellation processing by a digital end algorithm, which may be, for example, an MMSE-IRC algorithm.

In the above signal transceiving method, since various electric appliances are added on the power line, electric appliance noise is included in the signal transmitted on the power line, that is, electric appliance noise of a differential mode is included in both the two differential mode signals received by coupling. Meanwhile, since the electrical noise has strong common mode characteristics, the electrical noise of the common mode is included in the coupled received common mode signal. Because the electrical noise in the two paths of differential mode signals has correlation with the electrical noise of the common mode, the electrical 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 transceiver circuit, a fifth coupling transformer and a fifth transceiver 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 with the live wire and the zero wire, and the fourth coupling transformer is coupled to the fourth transceiver circuit. The fifth coupling transformer is connected with the live wire, the zero wire and the ground wire, and 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 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 receiving and transmitting method comprises the steps S1001-S1011, and specifically comprises the following steps:

S1001, a fourth coupling transformer couples a fourth differential mode signal received from the live and neutral wires to a fourth transceiver circuit.

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

S1003, the fifth coupling transformer couples the fifth differential mode signals received from the live, neutral and ground wires to the fifth transceiver circuit.

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

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

S1005, a common mode transformer couples the common mode signals received from the live, neutral and ground lines to the common mode signal receiving circuit.

S1006, the common mode signal receiving circuit receives a common mode signal of which the common mode transformer is coupled to the common mode signal receiving circuit.

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 so as to obtain amplified differential mode signals and common mode signals.

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

S1010, the digital interface receives the digital signal.

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

Referring to fig. 11, fig. 11 is a schematic diagram of performance gain achieved by receiving signals by the signal transceiver circuit according to the embodiment of the present application. As shown in fig. 11, a white bar graph is a schematic diagram of performance gain achieved by receiving three signals through a conventional T-type coupling circuit, and a black bar graph is a schematic diagram of performance gain achieved by introducing a common mode coupling circuit to receive three signals (including a common mode signal) on the basis of the T-type coupling circuit provided by the embodiment of the present application. The signal receiving and transmitting circuit provided by the embodiment of the application receives signals, and compared with the conventional circuit, the signal receiving and transmitting circuit achieves performance gain, and the signal receiving and transmitting circuit provided by the embodiment of the application can achieve performance improvement of 5-78% under the interference of various electrical noises.

The foregoing has outlined rather broadly the more detailed description of embodiments of the application, wherein the principles and embodiments of the application are explained in detail using specific examples, the above examples being provided solely to facilitate the understanding of the method and core concepts of the application; meanwhile, as those skilled in the art will appreciate, modifications will be made in the specific embodiments and application scope in accordance with the idea of the present application, and the present disclosure should not be construed as limiting the present application.

Claims

1. The signal transceiving circuit for power line communication is characterized in that the circuit comprises a differential mode coupling circuit, a common mode coupling circuit and a noise processing circuit, wherein the differential mode coupling circuit and the common mode coupling circuit are respectively connected with a power line, the noise processing circuit is connected with the differential mode coupling circuit and the common mode coupling circuit, the common mode coupling circuit comprises a common mode transformer, and the power line comprises at least one of the following components: a live wire, a zero wire and a ground wire, wherein,

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, wherein the common mode transformer is connected in series 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.

2. 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 is configured to receive the differential mode signal coupled to the each transceiver circuit by the each coupling transformer.

3. The circuit of claim 1, wherein the common mode coupling circuit further comprises 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, wherein,

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

the common mode signal receiving circuit is configured to receive the common mode signal of the common mode transformer coupled to the common mode signal receiving circuit.

4. The circuit of claim 1, wherein the differential mode coupling circuit comprises a first coupling transformer, a first transceiver circuit, a second coupling transformer, and a second transceiver circuit, the first coupling transformer being connected to two of the power lines, the first coupling transformer being coupled to the first transceiver circuit, the second coupling transformer being connected to two of the power lines, the second coupling transformer being coupled to the second transceiver circuit, the two of the power lines being one of a hot line, a neutral line, and a ground line, the two of the power lines to which the first coupling transformer is connected being different from the two of the power lines to which the second coupling transformer is connected, wherein,

the first coupling transformer is used for coupling first differential mode signals received from two lines of the power lines to the first transceiver circuit;

The first transceiver circuit is configured to receive the first differential mode signal coupled to the first transceiver circuit by the first coupling transformer;

the second coupling transformer is used for coupling second differential mode signals received from two lines 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.

5. The circuit of claim 4, wherein the differential mode coupling circuit further comprises a third coupling transformer and a third transceiver circuit, the third coupling transformer being connected to two of the power lines, the third coupling transformer being coupled to the third transceiver 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 the two of the power lines to which the second coupling transformer is connected being different,

the third coupling transformer is used for coupling a third differential mode signal received from two lines 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.

6. The circuit of claim 1, wherein the differential mode coupling circuit comprises a fourth coupling transformer, a fourth transceiver circuit, a fifth coupling transformer, and a fifth transceiver circuit, the fourth coupling transformer being coupled to at least two of the power lines, the fourth coupling transformer being coupled to the fourth transceiver circuit, the fifth coupling transformer being coupled to at least two of the power lines, the fifth coupling transformer being coupled to the fifth transceiver circuit, at least two of the power lines being either a hot, a neutral, and a ground line or a hot, a neutral, and a ground line, at least one of the fourth coupling transformer and the fifth coupling transformer being coupled to the hot, the neutral, and the ground line, wherein,

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

the fourth transceiver circuit is configured to receive the fourth differential mode signal coupled to the fourth transceiver circuit by the fourth coupling transformer;

The fifth coupling transformer is configured to couple a fifth differential mode signal received from at least two lines 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.

7. The circuit of claim 6, wherein the differential mode coupling circuit further comprises a sixth coupling transformer and a sixth transceiver circuit, the sixth coupling transformer being connected to at least two of the power lines, the sixth coupling transformer being coupled to the sixth transceiver circuit, wherein,

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

the sixth transceiver circuit is configured to receive the sixth differential mode signal coupled to the sixth transceiver circuit by the sixth coupling transformer.

8. The circuit of any one 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 coupled to the differential mode coupling circuit and the common mode coupling circuit through the analog interface, the digital front end being coupled to the analog front end through the digital interface, the analog front end comprising an adjustable 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 a common mode signal;

the analog-to-digital converter is used for sampling the amplified differential mode signal and the 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.

9. The signal transceiving method for the power line communication is characterized in that the signal transceiving circuit applied to the power line communication comprises a differential mode coupling circuit, a common mode coupling circuit and a noise processing circuit, wherein the differential mode coupling circuit and the common mode coupling circuit are respectively connected with a power line, the noise processing circuit is connected with the differential mode coupling circuit and the common mode coupling circuit, the common mode coupling circuit comprises a common mode transformer, and the power line comprises at least one of the following components: a hot, neutral and ground wire, the method comprising:

the noise processing circuit processes the common mode signal and the differential mode signal to eliminate noise in the differential mode signal.

10. The method of claim 9, 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 circuits, the differential mode coupling circuit coupling receiving a differential mode signal on the power lines 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 is coupled to the each transceiver circuit.

11. The method of claim 9, wherein the common mode coupling circuit further comprises 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 coupling receiving 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 of the common mode transformer coupled to the common mode signal receiving circuit.

12. The method of claim 9, wherein the differential mode coupling circuit comprises a first coupling transformer, a first transceiver circuit, a second coupling transformer, and a second transceiver circuit, the first coupling transformer being connected to two of the power lines, the first coupling transformer being coupled to the first transceiver circuit, the second coupling transformer being connected to two of the power lines, the second coupling transformer being coupled to the second transceiver circuit, the two of the power lines being two of a hot line, a neutral line, and a ground line, the two of the power lines connected by the first coupling transformer being different than the two of the power lines connected by the second coupling transformer, the differential mode coupling circuit coupling receiving a differential mode signal on the power lines comprising:

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

the first transceiver circuit receives the first differential mode signal coupled to the first transceiver circuit by the first coupling transformer;

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

the second transceiver circuit receives the second differential mode signal coupled to the second transceiver circuit by the second coupling transformer.

13. 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 being connected to two of the power lines, the third coupling transformer being coupled to the third transceiver 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 the two of the power lines to which the second coupling transformer is connected being different, the differential mode coupling circuit coupling receiving a differential mode signal on the power lines further comprising:

The third coupling transformer couples a third differential mode signal received from two of the power lines to the third transceiver circuit;

the third transceiver circuit receives the third differential mode signal coupled to the third transceiver circuit by the third coupling transformer.

14. The method of claim 9, wherein the differential mode coupling circuit comprises a fourth coupling transformer, a fourth transceiver circuit, a fifth coupling transformer, and a fifth transceiver circuit, the fourth coupling transformer being coupled to at least two of the power lines, the fourth coupling transformer being coupled to the fourth transceiver circuit, the fifth coupling transformer being coupled to at least two of the power lines, the fifth coupling transformer being coupled to the fifth transceiver circuit, at least two of the power lines being either a hot, a neutral, and a ground line or a hot, a neutral, and a ground line, at least one of the fourth coupling transformer and the fifth coupling transformer being coupled to the hot, neutral, and ground line, the differential mode coupling circuit coupling receiving a differential mode signal on the power line comprising:

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

the fourth transceiver circuit receives the fourth differential mode signal coupled to the fourth transceiver circuit by the fourth coupling transformer;

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

the fifth transceiver circuit receives the fifth differential mode signal coupled to the fifth transceiver circuit by the fifth coupling transformer.

15. The method of claim 14, wherein the differential mode coupling circuit further comprises a sixth coupling transformer and a sixth transceiver circuit, the sixth coupling transformer being connected to at least two of the power lines, the sixth coupling transformer being coupled to the sixth transceiver circuit, the differential mode coupling circuit coupling receiving a differential mode signal on the power lines further comprising:

the sixth coupling transformer couples a sixth differential mode signal received from at least two of the power lines to the sixth transceiver circuit;

the sixth transceiver circuit receives the sixth differential mode signal coupled to the sixth transceiver circuit by the sixth coupling transformer.

16. 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 being coupled to the differential mode coupling circuit and the common mode coupling circuit through the analog interface, the digital front end being coupled to the analog front end through the digital interface, the analog front end comprising an adjustable amplifier and an analog-to-digital converter, the noise processing circuit processing the common mode signal and the differential mode signal to cancel noise in the differential mode signal comprising:

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 a common mode signal;

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

the digital interface receives the digital signal;

the digital front end processes the digital signals received by the digital interface to eliminate noise.