PLC communication method and device, chip, chip module and storage medium

Abstract

The invention discloses a PLC communication method and device, a chip, a chip module and a storage medium. The method comprises: generating a first signal, where the first signal is repeated in n orthogonal spatial domain directions or space-time directions; and sending the first signal in the n orthogonal airspace directions or space-time directions of an m-dimensional linear space, m and n being positive integers, and m > = n. By adopting the scheme of the invention, the reliability of PLC communication is improved by repeatedly sending signals in a plurality of orthogonal airspace directions or space-time directions.

Description

Technical Field

[0001] The present application relates to the field of power line communication (PLC), and in particular, to a PLC communication method, apparatus, chip, chip module, and storage medium. Background Art

[0002] Since power lines are not specifically used as a communication medium, the environmental characteristics of power lines (mainly power line noise, load and impedance, environmental time-variation, etc.) have created some characteristics of PLC communication (time-varying, large attenuation, complex various interference noises).

[0003] Space-time codes can be used for broadcast frames to improve the diversity gain.

[0004] However, the signals sent in some directions are less reliable due to strong noise interference. Therefore, how to improve the reliability of PLC communication is an urgent problem to be solved. Summary of the Invention

[0005] The present application provides a PLC communication method, apparatus, chip, chip module, and storage medium to improve the reliability of PLC communication.

[0006] In a first aspect, a PLC communication method is provided, which is applied to a first PLC node, or a circuit or chip for the first PLC node. The method includes: generating a first signal, where the first signal is repeated in n orthogonal spatial domain directions or space-time directions; and sending the first signal in the n orthogonal spatial domain directions or space-time directions in an m-dimensional linear space, where m and n are positive integers and m≥n.

[0007] In this aspect, by repeatedly sending signals in multiple orthogonal spatial domain directions or space-time directions, the reliability of PLC communication is improved.

[0008] In a second aspect, a PLC communication apparatus is provided, which can implement the method in the first aspect or any implementation in the first aspect. The above method can be implemented by software, hardware, or by hardware executing corresponding software.

[0009] In a possible implementation, the apparatus includes: a processing unit and a transceiver unit; where the processing unit is configured to generate a first signal, where the first signal is repeated in n orthogonal spatial domain directions or space-time directions; and the transceiver unit is configured to send the first signal in the n orthogonal spatial domain directions or space-time directions in an m-dimensional linear space, where m and n are positive integers and m≥n.

[0010] In another possible implementation, the device in the second aspect above includes a processor coupled to a memory; the processor is configured to support the device in performing the corresponding functions in the above method. The memory is used to be coupled to the processor and stores the necessary programs (instructions) and / or data of the device. Optionally, the device may further include an interface for supporting the interaction between the device and other devices. Optionally, the memory may be located inside the device or outside the device. Optionally, the memory and the processor may be integrated together.

[0011] In yet another possible implementation, the device in the second aspect above includes a processor and an interface circuit, the processor is coupled to the interface circuit, and the processor is used to execute a computer program or instruction to control the interface circuit to receive and send information; when the processor executes the computer program or instruction, the processor is further used to implement the above method through a logic circuit or execute code instructions. Wherein, the interface circuit may be a transceiver, a transceiver circuit or an input / output interface, and is used to receive a signal from another device outside the device and transmit it to the processor, or send a signal from the processor to another device outside the device. When the device is a chip, the interface circuit is a transceiver circuit or an input / output interface.

[0012] When the device in the second aspect above is a chip or a chip module, the sending unit may be an output unit, such as an output circuit or an interface; the receiving unit may be an input unit, such as an input circuit or an interface.

[0013] Combined with the first aspect or the second aspect, in one possible implementation, the first signal includes a control field, and the control field is used to indicate that the first signal is repeated in n orthogonal spatial domain directions or space-time directions.

[0014] In this implementation, by indicating in the control field of the first signal that the first signal is repeated in n orthogonal spatial domain directions or space-time directions, the receiving end (such as the second PLC node) can accurately receive and demodulate the first signal.

[0015] Combined with the first aspect or the second aspect, in another possible implementation, m = 2, n = 2, and the first signal is sent by two transmitters, and the first signal s 0 satisfies:

[0016]

[0017] where y(0) is the received signal at the 0th moment, and y * (1) is the conjugate of the received signal y(1) at the 1st moment, and h 0is the channel gain from the first transmitter to the receiving antenna, h 1 is the channel gain from the second transmitter to the receiving antenna, n(0) is the noise at the 0th moment, n * (1) is the conjugate of the noise n(1) at the 1st moment, is the conjugate of h 0 ; is the conjugate of h 1 ;

[0018] First direction Second direction The first direction and the second direction are orthogonal to each other.

[0019] Exemplarily, the received signal at the 0th moment can be the kth subcarrier of the 0th orthogonal frequency division multiplexing (OFDM) symbol; the received signal at the 1st moment can be the kth subcarrier of the 1st OFDM symbol. Herein, k is a positive integer.

[0020] Exemplarily, the control field includes 1 bit, and the 1 bit is used to indicate whether the first signal is repeated in 2 orthogonal spatial directions or space-time directions.

[0021] In this implementation, for the scenario of two transmitters, by repeating the signal transmission in 2 orthogonal spatial directions or space-time directions, the reliability of PLC communication is improved.

[0022] Combined with the first aspect or the second aspect, in another possible implementation, m = 4, n = 3, the first signal is transmitted by three transmitters, and the first signal s 0 satisfies:

[0023]

[0024] wherein, y(0) is the received signal at the 0th moment, y * (1) is the conjugate of the received signal y(1) at the 1st moment, y * (2) is the conjugate of the received signal y(2) at the 2nd moment, y * (3) is the conjugate of the received signal y(3) at the 3rd moment, h 0 is the channel gain from the first transmitter to the receiving antenna, h 1 is the channel gain from the second transmitter to the receiving antenna, h 2 is the channel gain from the third transmitter to the receiving antenna, n(0) is the noise at the 0th moment, n * (1) is the conjugate of the noise n(1) at the 1st moment, n *(2) is the conjugate of the noise n(2) at the second moment, n * (3) is the conjugate of the noise n(3) at the third moment, is the conjugate of h 0 ; is the conjugate of h 1 ; is the conjugate of h 2 ;

[0025] First direction Second direction Third direction The first direction, the second direction, and the third direction are orthogonal to each other pairwise.

[0026] Exemplarily, the received signal at the 0th moment can be the kth subcarrier of the 0th OFDM symbol; the received signal at the 1st moment can be the kth subcarrier of the 1st OFDM symbol; the received signal at the 2nd moment can be the kth subcarrier of the 2nd OFDM symbol; the received signal at the 3rd moment can be the kth subcarrier of the 3rd OFDM symbol. Wherein, k is a positive integer.

[0027] Exemplarily, the control field includes 1 bit, and the 1 bit is used to indicate whether the first signal is repeated in 3 orthogonal spatial directions or space-time directions.

[0028] In this implementation, for the scenario of three transmitters, by repeatedly transmitting signals in 3 orthogonal spatial directions or space-time directions, the reliability of PLC communication is improved.

[0029] Combined with the first aspect or the second aspect, in another possible implementation, m = 4, n = 4, the first signal is transmitted by three transmitters, and the first signal s 0 satisfies:

[0030]

[0031] Wherein, y(0) is the received signal at the 0th moment, y * (1) is the conjugate of the received signal y(1) at the 1st moment, y * (2) is the conjugate of the received signal y(2) at the 2nd moment, y(3) is the received signal at the 3rd moment, h 0 is the channel gain from the first transmitter to the receiving antenna, h 1 is the channel gain from the second transmitter to the receiving antenna, h 2 is the channel gain from the third transmitter to the receiving antenna, n(0) is the noise at the 0th moment, n * (1) is the conjugate of the noise n(1) at the 1st moment, n* (2) is the conjugate of the noise n(2) at the second moment, n * (3) is the conjugate of the noise n(3) at the third moment, is the conjugate of h 0 of, is the conjugate of h 1 of, is the conjugate of h 2 of;

[0032] First direction Second direction Third direction Fourth direction The first direction is orthogonal to the second direction and the third direction, the fourth direction is orthogonal to the second direction and the third direction, the second direction is orthogonal to the first direction and the fourth direction, and the third direction is orthogonal to the first direction and the fourth direction.

[0033] Exemplarily, the received signal at the 0th moment can be the kth subcarrier of the 0th OFDM symbol; the received signal at the 1st moment can be the kth subcarrier of the 1st OFDM symbol; the received signal at the 2nd moment can be the kth subcarrier of the 2nd OFDM symbol; the received signal at the 3rd moment can be the kth subcarrier of the 3rd OFDM symbol. Wherein, k is a positive integer.

[0034] In this implementation, for the scenario of three transmitters, by repeatedly transmitting signals in 4 orthogonal spatial directions or space-time directions, the reliability of PLC communication is improved.

[0035] Combined with the first aspect or the second aspect, in another possible implementation, the first signal is also repeated on multiple time-frequency domain resources.

[0036] In this implementation, in addition to repeatedly transmitting signals in orthogonal spatial directions or space-time directions, signals can also be repeatedly transmitted in the time-frequency domain, further improving the reliability of PLC communication.

[0037] In a third aspect, a computer-readable storage medium is provided, in which a computer program or instruction is stored. When a computer executes the computer program or instruction, the method described in the first aspect or any implementation of the first aspect is implemented.

[0038] In a fourth aspect, a computer program product containing instructions is provided. When the instructions run on a device, the device is caused to execute the method described in the first aspect or any implementation of the first aspect. Description of the Drawings

[0039] Figure 1Schematic diagram of the networking method for power line carrier communication;

[0040] Figure 2 Schematic diagram of the structure for PLC communication in three-phase electricity;

[0041] Figure 3 Schematic flowchart of a PLC communication method provided by an embodiment of the present application;

[0042] Figure 4 Schematic diagram of the structure of a PLC communication device provided by an embodiment of the present application;

[0043] Figure 5 Schematic diagram of the structure of another PLC communication device provided by an embodiment of the present application. Detailed implementation manners

[0044] The embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application.

[0045] PLC is a communication method that uses power lines as the transmission medium. The PLC technology is widely used and can be applied to fields such as smart grids, smart homes, and industrial automation. The basic principle of the PLC technology is to use power lines as the transmission medium and transmit digital signals by changing the voltage, current, etc. of the power lines. The PLC technology mainly includes links such as modulation and demodulation, signal transmission, and signal processing. Among them, modulation and demodulation is to convert digital signals into analog signals, signal transmission is to transmit analog signals through power lines, and signal processing is to convert the transmitted analog signals back into digital signals.

[0046] The power line high-speed carrier communication technology adopts the OFDM modulation technology, so as to ensure reliable data transmission in a harsh environment of multipath and electromagnetic interference. Power lines are not specifically used as a communication medium, so the characteristics of the power line environment have created some characteristics of PLC communication. The environmental characteristics mainly include power line noise, load and impedance, and environmental time-variation. The transmission characteristics of the power line carrier channel are: having time-variation, large attenuation, and complex various interference noises.

[0047] The networking method of power line carrier communication is as Figure 1 shown, a tree-shaped network with a central coordinator (CCO) as the center and a proxy coordinator (PCO) as the relay proxy, connecting all stations (STA) in a multi-level association. Among them, the CCO is the main node in the communication network, responsible for completing functions such as networking control and network maintenance management, and performing point-to-point communication with the STA; the PCO performs data relay forwarding between the CCO and the STA, or between the STA and the STA.

[0048] The PLC node in this application is a module with PLC communication capabilities and can be installed in power equipment such as concentrators, switches, and electricity meters. It is divided into roles such as CCO, PCO, and STA.

[0049] Among them, the concentrator is the central management device and control device of the remote centralized meter reading system, responsible for functions such as regularly reading terminal data, transmitting system commands, data communication, network management, event recording, and horizontal transmission of data.

[0050] Among them, the PLC network refers to a tree-shaped network composed of PLC nodes in roles such as CCO, PCO, and STA.

[0051] CCO: It is the root node of the PLC network, generally installed in the concentrator, collects information of all PLC nodes in the PLC network, and then transmits it to the power bureau computer room through communication methods such as 4G / 5G / fiber optic.

[0052] PCO: The communication nodes of the power line network will form a tree-shaped network. The leaf node STA communicates with the CCO through the proxy node PCO as a relay, and may pass through multiple levels of proxies. PLC nodes can be installed at positions such as power switches and electricity meters to act as PCOs. The topology of the tree-shaped network is adaptively changing, and when the topology changes, the PCO role of the PLC node may continuously switch with the STA role.

[0053] STA: It is the terminal node of the power line network and does not act as a relay for other nodes. PLC nodes can be installed at positions such as power switches and electricity meters to act as STAs. The topology of the tree-shaped network is adaptively changing, and when the topology changes, the PCO role of the PLC node may continuously switch with the STA role.

[0054] In the PLC network, there are two types of signal frames: broadcast frames and unicast frames.

[0055] For unicast frames, training for transmit beamforming (tx beamforming) and training for bit loading can be performed between two stations during point-to-point communication, and then communication can be carried out between the two stations.

[0056] For broadcast frames, generally no training can be performed because there are many receiving nodes, and there is no beamforming and bit loading scheme that is optimal for all nodes to receive broadcast frames.

[0057] Taking the application of PLC technology in the smart grid field as an example, most single-phase meters in the PLC network have only 1 receiving port, and the receiving performance of single-phase meters is limited.

[0058] For three-phase meters applying PLC technology, there is three-phase power at the distribution box position, and signals can be sent using 2 ports or 3 ports. Such asFigure 2 Schematic diagram of the structure for PLC communication in the three-phase power shown, the transmitting end (which can be located on the distribution box) includes three transmitting ports, namely port 0, port 1, and port 2, which are respectively connected to the AN phase, BN phase, and CN phase of the distribution box; the receiving end includes three receiving ports, namely port 0, port 1, and port 2, which are respectively connected to the AN phase, BN phase, and CN phase. Among them, A / B / C are the live wires of the 220V power line, and N is the neutral wire of the 220V power line.

[0059] Among them, the above-mentioned smart grid refers to a new type of power grid formed by highly integrating modern advanced sensing and measurement technologies, communication technologies, information technologies, computer technologies, and control technologies with the physical power grid based on the physical power grid.

[0060] Space-time codes can be used to improve the diversity gain of broadcast frames. The current space-time codes can be used in the scenario of multiple transmissions (TX) and one reception (RX) to improve the diversity reception performance of 1RX.

[0061] (1) The complex orthogonal space-time code for 2 transmit antennas and 1 receive antenna is as follows:

[0062]

[0063] Among them, the first transmitter TX0 sends s at the 0th moment 0 , and sends at the 1st moment. The second transmitter TX1 sends s at the 0th moment 1 , and sends is the conjugate of s 0 ; is the conjugate of s 1 .

[0064] y(0) is the received signal at the 0th moment, y(1) is the received signal at the 1st moment, h 0 is the channel gain from the first transmitter to the receive antenna, h 1 is the channel gain from the second transmitter to the receive antenna, n(0) is the noise at the 0th moment, and n(1) is the noise at the 1st moment.

[0065] The above formula 1 can be written in another form:

[0066]

[0067] can be regarded as v 0 and v 1 are orthogonal

[0068] It can be regarded as the signal being transmitted in two mutually orthogonal directions in a 2D linear space. This space-time code transmits two symbols in two time slots, and the code rate R = 1, which is less than the code rate R = 2 of spatial multiplexing.

[0069] (2) The complex orthogonal space-time code for 3 transmit antennas and 1 receive antenna is as follows:

[0070]

[0071] Formula 3

[0072] Among them, the first transmitter TX0 sends s at time 0 0 , and sends at time 1, at time 2, and

[0073] sends 0 at time 3: The second transmitter TX1 sends s at time 0 1 , and sends

[0074] at time 1, sends 0 at time 2, and sends at time 3

[0075] Among them, y(0) is the received signal at time 0, y(1) is the received signal at time 1, y(2) is the received signal at time 2, y(3) is the received signal at time 3, h 0 is the channel gain from the first transmitter to the receive antenna, h 1 is the channel gain from the second transmitter to the receive antenna, h 2 is the channel gain from the third transmitter to the receive antenna, n(0) is the noise at time 0, n(1) is the noise at time 1, n(2) is the noise at time 2, and n(3) is the noise at time 3.

[0076] is the conjugate of s 0 ; is the conjugate of s 1 ; is the conjugate of s 2 .

[0077] The above Formula 3 can be written in another form:

[0078]

[0079] It can be regarded as v 0 and v 1Orthogonal v 0 and v 2 Orthogonal v 1 and v 2 Orthogonal

[0080] The signals are transmitted in three mutually orthogonal directions in a 4D linear space. This space-time code transmits three symbols in four time slots, and the code rate R = 3 / 4, which is less than the code rate R = 1 of the space-time code of TX2.

[0081] (3) The quasi-orthogonal space-time code for 3 transmit antennas and 1 receive antenna is as follows:

[0082]

[0083] where y(0) is the received signal at the 0th moment, y(1) is the received signal at the 1st moment, y(2) is the received signal at the 2nd moment, y(3) is the received signal at the 3rd moment, h 0 is the channel gain from the first transmitter to the receive antenna, h 1 is the channel gain from the second transmitter to the receive antenna, h 2 is the channel gain from the third transmitter to the receive antenna, n(0) is the noise at the 0th moment, n(1) is the noise at the 1st moment, n(2) is the noise at the 2nd moment, and n(3) is the noise at the 3rd moment.

[0084] is the conjugate of s 0 ; is the conjugate of s 1 ; is the conjugate of s 2 ;

[0085] The above formula 5 can be written in another form:

[0086]

[0087] where the first direction the second direction the third direction the fourth direction

[0088] v 0 is orthogonal to v 1 and v 2 ;

[0089] v 3 is orthogonal to v 1 and v 2 ;

[0090] v 1 is orthogonal to v 0 and v 3 are orthogonal;

[0091] v 2 is orthogonal to v 0 and v 3 are orthogonal;

[0092] v 0 and v 3 as the first group, are orthogonal to v 1 and v 2 of the second group, but the v 0 and v 3 within the first group are not orthogonal, and the v 1 and v 2 within the second group are not orthogonal. The groups are orthogonal to each other, but the elements within the groups are not orthogonal, so it is called quasi-orthogonal.

[0093] For the quasi-orthogonal space-time code of 3 transmitters, 4 symbols are transmitted in 4 time slots, and the code rate is 1, which is higher than the code rate of 3 / 4 of the complex orthogonal space-time code.

[0094] In this article, "transmitter" can also be called "transmission port"; "receiver" can also be called "reception port".

[0095] However, different from white noise (the noise interference power is the same in each direction), for the main impulse noise in the PLC network, in the linear space, generally the impulse noise in a certain direction is stronger than that in other directions. For the complex orthogonal space-time code of 2 transmit antennas and 1 receive antenna or the complex orthogonal space-time code of 3 transmit antennas and 1 receive antenna above, different signals are transmitted in different orthogonal directions. It is possible that the signal in a certain orthogonal direction is strongly interfered by the impulse noise, resulting in the signal in that orthogonal direction not being received reliably.

[0096] In addition, in PLC communication, the OFDM signal format is generally used, and multiple repeated copies are made on different OFDM symbols and different frequency-domain subcarriers to obtain time-domain and frequency-domain diversity. However, only using time-domain and frequency-domain repeated diversity is insufficient in multi-input multi-output (MIMO) communication.

[0097] In view of this, this application provides a PLC communication scheme, which improves the reliability of PLC communication by repeatedly transmitting signals in multiple orthogonal spatial directions or space-time directions.

[0098] The PLC communication method provided by the embodiments of the present application will be described in detail below. It can be understood that in the present application, the first PLC node and the second PLC node are used as examples of the execution entities for this interaction schematic illustration, but the present application does not limit the execution entities of the interaction schematic illustration. For example, the first PLC node in the method provided by the present application may also be a chip, a chip system, a circuit or a processor applied to the first PLC node, and may also be a logical node, a logical module or software that can implement all or part of the functions of the first PLC node; the second PLC node in the method provided by the present application may also be a chip, a chip system, a circuit or a processor applied to the second PLC node, and may also be a logical node, a logical module or software that can implement all or part of the functions of the second PLC node.

[0099] As Figure 3 shown, it is a schematic flow chart of a PLC communication method provided by an embodiment of the present application. Exemplarily, the method may include the following steps:

[0100] S301. The first PLC node generates a first signal.

[0101] In this embodiment, the first PLC node serves as the sender. Exemplarily, the first PLC node may be Figure 1 any PLC node in the shown PLC network, such as CCO, PCO, STA.

[0102] Before sending the first signal, the first PLC node generates the first signal. In this embodiment, the first signal generated by the first PLC node is repeated in n orthogonal spatial directions or space-time directions, that is, the first PLC node makes a repeated copy of the first signal in n orthogonal spatial directions or space-time directions.

[0103] Among them, since the first signal is repeated in n orthogonal spatial directions, and the first PLC node sends in different spatial directions at different times, it can also be considered that the first signal is repeated in n orthogonal space-time directions.

[0104] In the PLC network, due to the main impulse noise in the PLC network, in the linear space, generally the impulse noise in a certain direction is stronger than that in other directions. Therefore, in this embodiment, the first PLC node making a repeated copy of the first signal in n orthogonal spatial directions or space-time directions can make the quality of the signal in at least one direction (the direction with weaker noise) at the receiving end (i.e., the second PLC node) better, so as to reliably receive and demodulate the first signal.

[0105] Further, for the first signal control field, the control field is used to indicate that the first signal is repeated in n orthogonal spatial directions or space-time directions. By indicating in the control field of the first signal that the first signal is repeated in n orthogonal spatial directions or space-time directions, the second PLC node can accurately receive and demodulate the first signal.

[0106] In the first example, m = 2, n = 2, the first signal is transmitted by two transmitters, and the first signal s 0 satisfies:

[0107]

[0108] where y(0) is the received signal at the 0th moment, and y * (1) is the conjugate of the received signal y(1) at the 1st moment, h 0 is the channel gain from the first transmitter to the receiving antenna, and h 1 is the channel gain from the second transmitter to the receiving antenna, n(0) is the noise at the 0th moment, and n * (1) is the conjugate of the noise n(1) at the 1st moment, is the conjugate of h 0 ; is the conjugate of h 1 ;

[0109] The first direction The second direction The first direction and the second direction are orthogonal to each other.

[0110] Exemplarily, the received signal at the 0th moment can be the kth subcarrier of the 0th OFDM symbol; the received signal at the 1st moment can be the kth subcarrier of the 1st OFDM symbol. Where k is a positive integer.

[0111] Exemplarily, the above control field can include 1 bit, and this 1 bit is used to indicate whether the first signal is repeated in 2 orthogonal spatial directions or space-time directions. For example, when the value of this 1 bit is "1", it is used to indicate that the first signal is repeated in 2 orthogonal spatial directions or space-time directions; when the value of this 1 bit is "0", it is used to indicate that the first signal is not repeated in 2 orthogonal spatial directions or space-time directions. Vice versa.

[0112] For the scenario of the above two transmitters, by repeatedly transmitting the signal in 2 orthogonal spatial directions or space-time directions, the reliability of PLC communication is improved.

[0113] In the second example, m = 4, n = 3, the first signal is transmitted by three transmitters, and the first signal s 0 satisfies:

[0114]

[0115] Among them, y(0) is the received signal at the 0th moment, and y * (1) is the conjugate of the received signal y(1) at the 1st moment, and y * (2) is the conjugate of the received signal y(2) at the 2nd moment, and y * (3) is the conjugate of the received signal y(3) at the 3rd moment, and h 0 is the channel gain from the first transmitter to the receiving antenna, and h 1 is the channel gain from the second transmitter to the receiving antenna, and h 2 is the channel gain from the third transmitter to the receiving antenna. n(0) is the noise at the 0th moment, and n * (1) is the conjugate of the noise n(1) at the 1st moment, and n * (2) is the conjugate of the noise n(2) at the 2nd moment, and n * (3) is the conjugate of the noise n(3) at the 3rd moment, is the conjugate of h 0 ; is 's conjugate, is the conjugate of h 2 ;

[0116] The first direction The second direction The third direction The first direction, the second direction, and the third direction are mutually orthogonal to each other.

[0117] Exemplarily, the received signal at the 0th moment can be the kth subcarrier of the 0th OFDM symbol; the received signal at the 1st moment can be the kth subcarrier of the 1st OFDM symbol; the received signal at the 2nd moment can be the kth subcarrier of the 2nd OFDM symbol; the received signal at the 3rd moment can be the kth subcarrier of the 3rd OFDM symbol. Among them, k is a positive integer.

[0118] Exemplarily, the above control field includes 1 bit, and this 1 bit is used to indicate whether the first signal is repeated in 3 orthogonal spatial directions or space-time directions. For example, when the value of this 1 bit is "1", it is used to indicate that the first signal is repeated in 3 orthogonal spatial directions or space-time directions; when the value of this 1 bit is "0", it is used to indicate that the first signal is not repeated in 3 orthogonal spatial directions or space-time directions. Vice versa.

[0119] For the scenario of the above three transmitters, by repeatedly transmitting signals in 3 orthogonal spatial directions or space-time directions, the reliability of PLC communication is improved.

[0120] In the third example, m = 4, n = 4, and the first signal is transmitted by three transmitters. The first signal s 0 satisfies:

[0121]

[0122] where y(0) is the received signal at the 0th moment, and y * (1) is the conjugate of the received signal y(1) at the 1st moment, y * (2) is the conjugate of the received signal y(2) at the 2nd moment, and y(3) is the received signal at the 3rd moment. h 0 is the channel gain from the first transmitter to the receiving antenna, and h 1 is the channel gain from the second transmitter to the receiving antenna, and h 2 is the channel gain from the third transmitter to the receiving antenna. n(0) is the noise at the 0th moment, and n * (1) is the conjugate of the noise n(1) at the 1st moment, and n * (2) is the conjugate of the noise n(2) at the 2nd moment, and n * (3) is the conjugate of the noise n(3) at the 3rd moment, is the conjugate of h 0 ; is the conjugate of h 1 ; is the conjugate of h 2 ;

[0123] First direction Second direction Third direction Fourth direction The first direction is orthogonal to the second and third directions, the fourth direction is orthogonal to the second and third directions, the second direction is orthogonal to the first and fourth directions, and the third direction is orthogonal to the first and fourth directions.

[0124] That is: v 0 is orthogonal to v 1 and v 2 ;

[0125] v 3 is orthogonal to v 1 and v 2 ;

[0126] v1 is orthogonal to v 0 and v 3 ;

[0127] v 2 is orthogonal to v0 and v 3 are orthogonal;

[0128] v can be 0 and v 3 as the first group, orthogonal to the second group of v 1 and v 2 However, the v 0 and v 3 within the first group are not orthogonal, and the v 1 and v 2 within the second group are not orthogonal. The groups are orthogonal to each other, but the elements within the groups are not orthogonal, so it is called quasi - orthogonal.

[0129] Exemplarily, the received signal at the 0th moment can be the k - th sub - carrier of the 0th OFDM symbol; the received signal at the 1st moment can be the k - th sub - carrier of the 1st OFDM symbol; the received signal at the 2nd moment can be the k - th sub - carrier of the 2nd OFDM symbol; the received signal at the 3rd moment can be the k - th sub - carrier of the 3rd OFDM symbol. Wherein, k is a positive integer.

[0130] In this example, s is repeatedly copied in 4 quasi - orthogonal spatial domain directions or space - time directions 0 .

[0131] For the scenario of the above three transmitters, by repeatedly transmitting signals in 4 orthogonal spatial domain directions or space - time directions, the reliability of PLC communication is improved.

[0132] Furthermore, the first signal can also be repeated on multiple time - frequency domain resources. Thus, in addition to repeatedly transmitting signals in orthogonal spatial domain directions or space - time directions, signals can also be repeatedly transmitted in the time - frequency domain, further improving the reliability of PLC communication.

[0133] For example, in the prior art, the first PLC node may make 4 copies at 4 time - frequency domain positions. However, simply using time - domain and frequency - domain repetition diversity is insufficient in MIMO communication.

[0134] In this embodiment, in the above first example, the first PLC node makes 2 copies in 2 orthogonal spatial domain directions or space - time directions, and at the same time makes 2 copies at 2 time - frequency domain positions, so that not only repeated copying is performed at time - frequency domain positions, but also repeated copying is performed in spatial domain directions or space - time directions, improving the diversity gain. Among them, if the first PLC node makes 2 copies in the space - time direction on the 0th and 1st OFDM symbols, then the first PLC node can make the first copy at the time - frequency domain position on the 0th or 1st OFDM symbol, and make the second copy at the time - frequency domain position on the 2nd or 3rd OFDM symbol.

[0135] Using this example, making 4 copies at 4 time-frequency domain positions relative to the first PLC node can further improve the diversity gain.

[0136] In the second example above, the first PLC node makes 3 copies in 3 orthogonal spatial directions or space-time directions, and also makes x copies at x time-frequency domain positions, so that repeated copies are made not only in the time-frequency domain positions but also in the spatial directions or space-time directions, improving the diversity gain. Among them, the first PLC node makes 3 copies in the space-time directions on the 0th, 1st, and 2nd OFDM symbols. Then the first PLC node can make the first copy at the time-frequency domain position on the 0th, 1st, or 2nd OFDM symbol, and make the (x - 1)th copy at the time-frequency domain position on the 3rd, 4th, or 5th OFDM symbol, and so on. Where x is a positive integer greater than or equal to 1.

[0137] In the third example above, the first PLC node makes 4 copies in 4 orthogonal spatial directions or space-time directions, and also makes y copies at y time-frequency domain positions, so that repeated copies are made not only in the time-frequency domain positions but also in the spatial directions or space-time directions, improving the diversity gain. Among them, the first PLC node makes 4 copies in the space-time directions on the 0th, 1st, 2nd, and 3rd OFDM symbols. Then the first PLC node can make the first copy at the time-frequency domain position on the 0th, 1st, 2nd, or 3rd OFDM symbol, and make the (y - 1)th copy at the time-frequency domain position on the 4th, 5th, 6th, or 7th OFDM symbol, and so on. Where y is a positive integer greater than or equal to 1.

[0138] S302. The first PLC node sends the first signal to the second PLC node in n orthogonal spatial directions or space-time directions in the m-dimensional linear space. Correspondingly, the second PLC node receives the first signal in n orthogonal spatial directions or space-time directions in the m-dimensional linear space.

[0139] After the first PLC node generates the first signal, it correspondingly sends the first signal to the second PLC node in n orthogonal spatial directions or space-time directions in the m-dimensional linear space. Where m and n are positive integers and m ≥ n.

[0140] This method can be applied to broadcast frames or unicast frames with fixed modulation and coding rate without bitloading or beamforming, which can improve the diversity gain.

[0141] According to a PLC communication method provided by an embodiment of the present application, by repeatedly sending signals in multiple orthogonal spatial directions or space-time directions, the reliability of PLC communication is improved.

[0142] In another embodiment, the first PLC node may repeatedly transmit signals in partially orthogonal spatial or space-time directions.

[0143] In a fourth example, m = 4, n = 3, the first signal is transmitted by three transmitters. In addition, the first PLC node also generates and transmits a second signal s 1 . Among them, the first signal s 0 and the second signal s 1 satisfy:

[0144]

[0145] Among them, y(0) is the received signal at the 0th moment, y * (1) is the conjugate of the received signal y(1) at the 1st moment, y * (2) is the conjugate of the received signal y(2) at the 2nd moment, y * (3) is the conjugate of the received signal y(3) at the 3rd moment, h 0 is the channel gain from the first transmitter to the receiving antenna, h 1 is the channel gain from the second transmitter to the receiving antenna, h 2 is the channel gain from the third transmitter to the receiving antenna, n(0) is the noise at the 0th moment, n * (1) is the conjugate of the noise n(1) at the 1st moment, n * (2) is the conjugate of the noise n(2) at the 2nd moment, n * (3) is the conjugate of the noise n(3) at the 3rd moment, is the conjugate of h 0 , is the conjugate of h 1 , is the conjugate of h 2 ;

[0146] The first direction The second direction The third direction The first direction, the second direction, and the third direction are mutually orthogonal to each other.

[0147] Exemplarily, the received signal at the 0th moment may be the kth subcarrier of the 0th OFDM symbol; the received signal at the 1st moment may be the kth subcarrier of the 1st OFDM symbol; the received signal at the 2nd moment may be the kth subcarrier of the 2nd OFDM symbol; the received signal at the 3rd moment may be the kth subcarrier of the 3rd OFDM symbol. Among them, k is a positive integer.

[0148] For the scenario of the above three transmitters, by repeatedly transmitting signals in two orthogonal spatial directions or space-time directions, the reliability of PLC communication is improved.

[0149] For the quasi-orthogonal space-time code of the above three transmit ports, there can be the following three copy schemes:

[0150] (1) Copy scheme 1, copy 4 times, and its quasi-orthogonal space-time code is as shown in the above formula 9;

[0151] (2) Copy scheme 2, copy 2 times, s 0 Transmit in two directions of the first group, s 1 Transmit in two directions of the second group, and its quasi-orthogonal space-time code is as follows:

[0152]

[0153] (3) Copy scheme 3, copy 2 times, s 0 and s 1 Transmit in two directions of the first group, and then copy to the second group orthogonal to the first group, and its quasi-orthogonal space-time code is as follows:

[0154]

[0155] For the quasi-orthogonal space-time code of three transmit ports, there are three copy schemes. The signal to be transmitted can include a control field, and the control field can include 2 bits. The values of the 2 bits respectively correspond to: "00" means no copy; "01" means copy scheme 1 is adopted; "10" means copy scheme 2 is adopted; "11" means copy scheme 3 is adopted. Both the first PLC node and the second PLC node have pre-stored the corresponding relationship between the above copy schemes and the values of the control field. Thus, after the second PLC node receives the signal and parses the control field, it can accurately receive and demodulate the received signal according to the control field.

[0156] In this application, "sending information to... (such as the second PLC node)" or the relevant schematic in the drawings can be understood as the destination of the information is the second PLC node. It can include directly or indirectly sending information to the second PLC node. "Receiving information from... (such as the second PLC node)" or "receiving information from... (such as the second PLC node)", or the relevant schematic in the drawings can be understood as the source of the information is the second PLC node, and it can include directly or indirectly receiving information from the second PLC node. The information may be subjected to necessary processing, such as format change, etc., between the source and the destination of the information transmission, but the destination can understand the valid information from the source. Similar expressions in this application can be understood similarly and will not be elaborated here.

[0157] The above mainly introduced the solution provided by the embodiments of the present application from the perspective of interactions between various nodes. Correspondingly, the embodiments of the present application also provide a PLC communication device, which is used to implement the above method. The PLC communication device may be the first PLC node in the above method embodiment, or a component applicable to the first PLC node; or, the PLC communication device may be the second PLC node in the above method embodiment, or a component applicable to the second PLC node. It can be understood that, in order to implement the above functions, the PLC communication device includes corresponding hardware structures and / or software modules for executing various functions. Those skilled in the art should easily realize that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a certain function is executed in the way of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present application.

[0158] The embodiments of the present application can divide functional modules for the PLC communication device according to the above method embodiments. For example, each functional module can be divided corresponding to each function, or two or more functions can be integrated into one processing unit. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiments of the present application is illustrative, only a logical function division, and there may be other division methods in actual implementation.

[0159] Based on the same concept of the above PLC communication method, the present application also provides the following PLC communication device:

[0160] As Figure 4 shown, it is a schematic structural diagram of a PLC communication device provided by an embodiment of the present application. The PLC communication device 400 includes a processing unit 410 and a transceiver unit 411; wherein,

[0161] When the PLC communication device 400 is used to implement the functions of the first PLC node in the method embodiment shown in Figure 3 : The processing unit 410 is used to implement step S301 in the embodiment shown in Figure 3 , and the transceiver unit 411 is used to implement the functions of the first PLC node in step S302 in the embodiment shown in Figure 3 .

[0162] For a more detailed description of the above processing unit 410 and transceiver unit 411, reference can be directly made to Figure 3The relevant descriptions in the method embodiments shown can be directly obtained and will not be elaborated here.

[0163] As Figure 5 shown, the figure is a schematic structural diagram of another PLC communication device provided by an embodiment of the present application. The PLC communication device 500 includes a processor 510 and may further include an interface circuit 520. The processor 510 and the interface circuit 520 are coupled to each other. It can be understood that the interface circuit 520 can be a transceiver or an input / output interface. Optionally, the PLC communication device 500 may further include a memory 530 (shown as a dotted line in the figure), which is used to store instructions executed by the processor 510, or input data required for the processor 510 to run the instructions, or data generated after the processor 510 runs the instructions.

[0164] When the PLC communication device 500 is used to implement Figure 3 the function of the first PLC node in the method embodiment shown: the processor 510 is used to implement step S301 in the embodiment shown as Figure 3 shown, and the interface circuit 520 is used to implement the function of the first PLC node in step S302 in the embodiment shown as Figure 3 shown.

[0165] For a more detailed description of the above-mentioned processor 510 and interface circuit 520, reference can be directly made to Figure 3 the relevant descriptions in the method embodiments shown. They will not be elaborated here.

[0166] The division of modules in the present application is illustrative, merely a logical function division. In actual implementation, there may be other division methods. In addition, in each example of the present application, each functional module can be integrated in a processor, or can exist independently physically, or two or more modules can be integrated in one module. The above-mentioned integrated modules can be implemented in the form of hardware or in the form of software functional modules.

[0167] It can be understood that the processor in the embodiments of the present application can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The general-purpose processor can be a microprocessor or any conventional processor.

[0168] The embodiments of the present application further provide a computer-readable storage medium, in which computer programs or instructions are stored. When the computer programs or instructions are executed, the methods in the above embodiments are implemented.

[0169] The embodiments of the present application further provide a computer program product containing instructions. When the instructions run on a computer, the computer is enabled to execute the methods in the above embodiments.

[0170] The embodiments of the present application further provide a communication system, including the above-mentioned first PLC node and second PLC node.

[0171] The embodiments of the present application further provide a circuit, which is coupled to a memory and is used to execute the methods shown in the above embodiments. The circuit may include a chip circuit.

[0172] When the above communication device is a module applied to the first PLC node, the first PLC node module implements the functions of the first PLC node in the above method embodiments. The first PLC node module receives information from other modules in the first PLC node, and the information is sent by the second PLC node to the first PLC node; or, the first PLC node module sends information to other modules in the first PLC node, and the information is sent by the first PLC node to the second PLC node.

[0173] It should be noted that one or more of the above units can be implemented by software, hardware, or a combination of both. When any of the above units is implemented by software, the software exists in the form of computer program instructions and is stored in a memory. The processor can be used to execute the program instructions and implement the above method processes.

[0174] In the present application, the processor can be a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field-programmable gate array, or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. Or, all or part of the circuits for implementing the processing functions in the foregoing devices can implement or execute the various methods, steps, and logic block diagrams disclosed in the present application. The general-purpose processor can be a microprocessor or any conventional processor, etc. The steps of the methods disclosed in combination with the present application can be directly embodied as being executed by a hardware processor, or executed by a combination of hardware and software modules in the processor.

[0175] When the above units or units are implemented in hardware, the hardware can be any one or any combination of a CPU, a microprocessor, a DSP chip, a microcontroller unit (MCU), an artificial intelligence processor, an ASIC, an SoC, an FPGA, a PLD, a dedicated digital circuit, a hardware accelerator, or a non-integrated discrete device, which can run the necessary software or execute the above method flow without relying on software.

[0176] Optionally, an embodiment of the present application further provides a chip system, including: at least one processor and an interface, the at least one processor is coupled to a memory through the interface, and when the at least one processor runs a computer program or instruction in the memory, the chip system is enabled to execute the method in any one of the above method embodiments. Optionally, the chip system may be composed of chips or may include chips and other discrete devices, and the embodiments of the present application do not make specific limitations thereto.

[0177] The memory in the present application may also be a circuit or any other device capable of implementing a storage function, for storing program instructions and / or data. The memory is any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. For example, the memory may be a non-volatile memory, such as a digital versatile disc (DVD), a hard disk drive (HDD), or a solid-state drive (SSD), etc., or may also be a volatile memory, such as a random-access memory (RAM).

[0178] It should be understood that in the description of this application, unless otherwise specified, " / " indicates that the objects associated before and after are in an "or" relationship. For example, A / B can represent A or B; where A and B can be singular or plural. Also, in the description of this application, unless otherwise specified, "a plurality of" means two or more than two. "At least one (item)" or its similar expression refers to any combination of these items, including any combination of a single item or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, a - b, a - c, b - c, or a - b - c, where a, b, and c can be single or multiple. Additionally, for the convenience of clearly describing the technical solutions of the embodiments of this application, in the embodiments of this application, terms such as "first" and "second" are used to distinguish the same or similar items with basically the same functions and roles. Those skilled in the art can understand that terms such as "first" and "second" do not limit the quantity and execution order, and terms such as "first" and "second" do not necessarily mean different. At the same time, in the embodiments of this application, words such as "exemplary" or "for example" are used to represent examples, illustrations, or explanations. Any embodiment or design solution described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Rather, using words such as "exemplary" or "for example" is intended to present relevant concepts in a specific manner for easy understanding.

[0179] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using a software program, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in the embodiments of this application are generated in whole or in part. The computer can be a general - purpose computer, a special - purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer - readable storage medium, or transmitted from one computer - readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wirelessly (such as infrared, wireless, microwave, etc.).

[0180] Although the present application has been described in connection with various embodiments, those skilled in the art can understand and achieve other variations of the disclosed embodiments by viewing the accompanying drawings, the disclosure, and the appended claims during the implementation of the claimed present application. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality. A single processor or other unit can implement several functions recited in the claims. Certain measures are recited in mutually different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0181] It can be understood that the various numerical numbers involved in the embodiments of the present application are only for the convenience of description and are not used to limit the scope of the embodiments of the present application. The magnitude of the serial numbers of the above processes does not mean the sequence of execution, and the execution sequence of each process should be determined by its function and internal logic.

[0182] In the above embodiments, the descriptions of the respective embodiments have their own emphases. For parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0183] The components in the device embodiments of the present application can be combined, divided, and deleted according to actual needs. Those skilled in the art can combine or combine the different embodiments and the features of different embodiments described in this specification.

[0184] In the present application, on the premise of no logical contradiction, the examples can refer to each other. For example, the methods and / or terms between method embodiments can refer to each other, for example, the functions and / or terms between device embodiments can refer to each other, and for example, the functions and / or terms between device examples and method examples can refer to each other.

Claims

1. A PLC communication method, characterized in that, the method includes: generating a first signal, wherein the first signal is repeated in n orthogonal spatial domain directions or space-time directions; transmitting the first signal in the n orthogonal spatial domain directions or space-time directions of an m-dimensional linear space, where m and n are positive integers and m ≥ n.

2. The method according to claim 1, characterized in that, the first signal includes a control field for indicating that the first signal is repeated in n orthogonal spatial domain directions or space-time directions.

3. The method according to claim 1 or 2, characterized in that, where m = 2, n = 2, the first signal is transmitted by two transmitters, and the first signal s 0 satisfies: where y(0) is the received signal at the 0th moment, y * (1) is the conjugate of the received signal y(1) at the 1st moment, h 0 is the channel gain from the first transmitter to the receiving antenna, h 1 is the channel gain from the second transmitter to the receiving antenna, n(0) is the noise at the 0th moment, n * (1) is the conjugate of the noise n(1) at the 1st moment, is the conjugate of h 0 ; is the conjugate of h 1 ; First direction Second direction The first direction and the second direction are orthogonal to each other.

4. The method according to claim 1 or 2, characterized in that, where m = 4, n = 3, the first signal is transmitted by three transmitters, and the first signal s 0 satisfies: Among them, y(0) is the received signal at the 0th moment, y * (1) is the conjugate of the received signal y(1) at the 1st moment, y * (2) is the conjugate of the received signal y(2) at the 2nd moment, y * (3) is the conjugate of the received signal y(3) at the 3rd moment, h 0 is the channel gain from the first transmitter to the receiving antenna, h 1 is the channel gain from the second transmitter to the receiving antenna, h 2 is the channel gain from the third transmitter to the receiving antenna, n(0) is the noise at the 0th moment, n * (1) is the conjugate of the noise n(1) at the 1st moment, n * (2) is the conjugate of the noise n(2) at the 2nd moment, n * (3) is the conjugate of the noise n(3) at the 3rd moment, is the conjugate of h 0 is the conjugate of h 1 is the conjugate of h 2 ;​​ First direction Second direction Third direction The first direction, the second direction, and the third direction are orthogonal to each other pairwise.

5. The method according to any one of claims 1-4, characterized in that, the first signal is also repeated on a plurality of time-frequency domain resources.

6. A PLC communication device, characterized in that, the device includes: a processing unit and a transceiver unit; wherein: the processing unit is configured to generate a first signal, wherein the first signal is repeated in n orthogonal spatial domain directions or space-time directions; the transceiver unit is configured to transmit the first signal in the n orthogonal spatial domain directions or space-time directions of an m-dimensional linear space, where m and n are positive integers and m ≥ n.

7. The device according to claim 6, characterized in that, the first signal includes a control field for indicating that the first signal is repeated in n orthogonal spatial domain directions or space-time directions.

8. The device according to claim 6 or 7, characterized in that, where m = 2, n = 2, the first signal is transmitted by two transmitters, and the first signal s 0 satisfies: where y(0) is the received signal at the 0th moment, y * (1) is the conjugate of the received signal y(1) at the 1st moment, h 0 is the channel gain from the first transmitter to the receiving antenna, h 1 is the channel gain from the second transmitter to the receiving antenna, n(0) is the noise at the 0th moment, n * (1) is the conjugate of the noise n(1) at the 1st moment, is the conjugate of h 0 ; is the conjugate of h 1 ; First direction Second direction The first direction and the second direction are orthogonal to each other.

9. The device according to claim 6 or 7, characterized in that, where m = 4, n = 3, the first signal is transmitted by three transmitters, and the first signal s 0 satisfies: Among them, y(0) is the received signal at the 0th moment, y * (1) is the conjugate of the received signal y(1) at the 1st moment, y * (2) is the conjugate of the received signal y(2) at the 2nd moment, y * (3) is the conjugate of the received signal y(3) at the 3rd moment, h 0 is the channel gain from the first transmitter to the receiving antenna, h 1 is the channel gain from the second transmitter to the receiving antenna, h 2 is the channel gain from the third transmitter to the receiving antenna, n(0) is the noise at the 0th moment, n * (1) is the conjugate of the noise n(1) at the 1st moment, n * (2) is the conjugate of the noise n(2) at the 2nd moment, n * (3) is the conjugate of the noise n(3) at the 3rd moment, is the conjugate of h 0 is the conjugate of h 1 is the conjugate of h 2 ;​​ First direction Second direction Third direction The first direction, the second direction and the third direction are orthogonal to each other in pairs.

10. The device according to any one of claims 6-9, characterized in that, the first signal is also repeated on a plurality of time-frequency domain resources.

11. A PLC communication device, characterized in that, it includes a processor and an interface circuit. The interface circuit is configured to receive a signal from another device outside the device and transmit it to the processor, or send a signal from the processor to another device outside the device. The processor is configured to implement the method according to any one of claims 1-5 through logic circuits or by executing code instructions.

12. A chip, characterized in that, the chip is configured to execute the method according to any one of claims 1-5.

13. A chip module, characterized in that, it includes a transceiver component and a chip. The chip is configured to execute the method according to any one of claims 1-5.

14. A computer-readable storage medium, characterized in that, the storage medium stores a computer program or instructions. When the computer program or instructions are executed by a PLC communication device, the method according to any one of claims 1-5 is implemented.

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