US-12621740-B2 - Transmission method and node device implementing said method

US12621740B2US 12621740 B2US12621740 B2US 12621740B2US-12621740-B2

Abstract

A transmission method makes it possible to transmit data from a first node device to a second node device belonging to a network neighbourhood of the first node device, the first and second node devices belonging to an electrical supply network. These nodes are configured for transmitting the data by powerline and by radio frequency. The method comprises the following steps performed by the first node device: distributing the data in two groups of data by an operation of interlacing the data, each group being associated with a communication medium from powerline and radio frequency, and transmitting each data item to a MAC layer of the communication medium associated with the group to which the data item belongs.

Inventors

Jérôme BAROIS
Guillaume BACRI

Assignees

SAGEMCOM ENERGY & TELECOM SAS

Dates

Publication Date: 20260505
Application Date: 20220811
Priority Date: 20210826

Claims (10)

1 . A transmission method for transmitting data from a first node device to a second node device belonging to a network neighbourhood of said first node device, said first and second node devices belonging to an electrical supply network and being configured for transmitting said data by powerline and by radio frequency, wherein the method causes said first node device to perform: distributing the data in two groups of data by an operation of interlacing said data, each group being associated with a communication medium from among powerline and radio frequency, and said operation of interlacing said data being carried out using either: (i) generating a first bit stream of N bits, each binary value being associated with one of the communication medium from among powerline and radio frequency, N being the number of data to be transmitted to the MAC layer, N being an integer greater than 0; permuting, by bit reversal, the bits in the first bit stream to obtain a second bit stream; and assigning each data item to the communication medium corresponding to the value of the bit at the same position in the second bit stream or, (ii) obtaining two interlacing tables, each interlacing table being associated with a communication medium and arranging the data to be transmitted within the interlacing tables; transmitting each data item to a MAC layer of the communication medium associated with the group to which said data item belongs.
2 . The method according to claim 1 , which causes said first node to perform encoding the data by a Reed-Solomon encoder and wherein distributing the data in two groups of data by an operation of interlacing said data applies to the encoded data.
3 . The method according to claim 1 , wherein transmitting each data item to a MAC layer of the communication medium associated with a group to which said data item belongs comprises: transmitting each data item to the MAC layer of the communication medium associated with the value of the bit corresponding to said data item in the second bit stream.
4 . The method according to claim 3 , wherein generating a first bit stream of N bits comprises: a) initialising the parameters k, N RF and N PLC to 0; b) if D PLC <D RF , positioning a bit b k at a first value and incrementing N RF by 1, otherwise positioning the bit b k at a second value and incrementing N PLC by 1, where D PLC is a rate available for the powerline communication medium and D RF is a rate available for the radio-frequency communication medium; c) if N PLC /(N PLC +N RF )≤D PLC /(D PLC +D RF ) positioning a bit b k+1 at said second value and incrementing N PLC by 1, otherwise positioning the bit b k+1 at said first value and incrementing N RF by 1; d) if (k+1)<N−1, incrementing k by 1 and resuming at the step c), k being an index that identifies a bit b k in the first bit stream; N PLC , respectively N RF representing a number of bits transmitted on the powerline communication medium, respectively the radio-frequency communication medium; D PLC being a rate of data available for the powerline communication medium and D RF being a rate of data available for the radio-frequency communication medium.
5 . The method according to claim 1 , wherein distributing the data in two groups of data by an operation of interlacing said data comprises: transmitting each data item to the MAC layer of the communication medium associated with the interlacing table in which said data item is located.
6 . The method according to claim 5 , wherein obtaining two interlacing tables, each interlacing table being associated with a communication medium, comprises: obtaining a first interlacing table noted T [m, n] of bits representing the data to be transmitted and wherein m is a number of row and n the number of column of the table T, the first interlacing table T comprising as many second interlacing tables Ti [m i , n i ] of bits as there are communication media, each second interlacing table Ti [m i , n i ] being attributed to only one of said communication media, differences in dimensions between second interlacing tables being liable to generate one or more so-called invalid positions included in the first interlacing table but not included in the at least one of the second interlacing tables, interlacing the bits by successive shifts of the rows m and of the columns n of the first interlacing table T [m, n], the successive shifts being performed in the form of circular permutations of the bits respectively by row and by column, moving any bit detected as present at an invalid position in the first interlacing table to a position in a second interlacing table that is available after the interlacing of the bits of the first interlacing table, so that each second interlacing table comprises bits allocated to one of said groups of data.
7 . The method according to claim 1 , wherein, in the case where a data item is transmitted by powerline, said data item is transmitted on at least one frequency band belonging to a set of frequency bands comprising: the CENELEC A frequency band which ranges from 35 kHz to 91 kHz; the CENELEC B frequency band which ranges from 98 kHz to 122 kHz; and the FCC frequency band which ranges from 150 kHz to 480 kHz or the ARIB frequency band which ranges from 150 kHz to 400 kHz.
8 . The method according to claim 1 , wherein, in the case where a data item is transmitted by radio frequency, said data item is transmitted on a frequency band ranging from 863 MHz to 870 MHz.
9 . A non-transitory storage medium storing a computer program comprising instructions for implementing, by a processor, the transmission method according to claim 1 , when said program is executed by said processor.
10 . A node device belonging to an electrical supply network, said node device being configured for transmitting data by powerline and by radio frequency to another node in said electrical supply network belonging to its network neighbourhood, wherein the node device comprises circuitry causing the node device to perform: distributing the data in two groups of data by an operation of interlacing said data, each group being associated with a communication medium from among powerline and radio frequency, said operation of interlacing said data being carried out using either: (i) generating a first bit stream of N bits, each binary value being associated with one of the communication medium from among powerline and radio frequency, N being the number of data to be transmitted to the MAC layer, N being an integer greater than 0; permuting, by bit reversal, the bits in the first bit stream to obtain a second bit stream; and assigning each data item to the communication medium corresponding to the value of the bit at the same position in the second bit stream or, (ii) obtaining two interlacing tables, each interlacing table being associated with a communication medium and arranging the data to be transmitted within the interlacing tables, and transmitting each data item to a MAC layer of the communication medium associated with a group to which said data item belongs.

Description

TECHNICAL FIELD At least one embodiment relates to a transmission method for transmitting data from a first node device to a second node device belonging to a network neighbourhood of the first node device, the first and second node devices being configured for transmitting the data by powerline and by radio frequency. At least one embodiment relates to a node device implementing said transmission method. PRIOR ART Powerline communications PLC are developing, in particular in the context of electrical supply networks of the AMM type (the acronym signifying “automated meter management”). Communication networks are thus implemented in electrical supply networks for the automated collection, by a base node device (also referred to as a “data concentrator”) in the network, from smart electricity meters, of energy consumption reading data that said smart electricity meters are respectively responsible for monitoring. The G3-PLC communication standard is defined to enable the various node devices (in particular data concentrator and smart electricity meters) in such a network to communicate with each other. The standard is specified in the ITU-T recommendation G.9903, which describes in particular the physical layer (PHY) and the data link layer (DLL) of the OSI model (the acronym for “Open Systems Interconnection”). The G3-PLC standard is intended to be used in frequency bands ranging from 10 to 490 kHz. It supports more particularly the following frequency bands: the CENELEC A frequency band, which ranges approximately from 35 kHz to 91 kHz; the FCC frequency band, which ranges approximately from 150 kHz to 480 kHz; the ARIB frequency band, which ranges approximately from 150 kHz to 400 kHz; and the CENELEC B frequency band, which ranges approximately from 98 kHz to 122 kHz. These various frequency bands have different characteristics in terms of rate, range and resistance to disturbances, in particular. In a development of the G3-PLC standard defined in an Annex H of the ITU-T recommendation G.9903 (2017) Amendment 1 (May 2021), called G3-PLC Hybrid PLC & RF, an RF (the acronym for radio-frequency) radio channel can be used in place of one of said PLC frequency bands. More precisely, this version of the standard allows the occasional use of a secondary radio physical layer based on an SUN FSK modulation as defined in IEEE 802.15.4:2015. Thus, by using the various G3-PL and RF media for transmitting data, the electrical supply network maximises its coverage and its resilience. An electrical-supply network node capable of sending and receiving data using the two media (PLC and RF) is called a hybrid node. However, in G3-PLC Hybrid PLC & RF, the choice of communicating between two hybrid nodes of the communication network either by powerline on a PLC frequency band or by radio frequency on an RF channel is determined at the time of construction or reconstruction of the communication routes. This choice of the communication medium used between two hybrid nodes of the network is generally fixed for several hours. Thus the unicast messages are transmitted between said two hybrid nodes during this period either on a PLC frequency band or on an RF channel according to the choice made at the time of the construction or reconstruction of the route. The G3-PLC Hybrid PLC & RF standard defined in Amendment 1 (May 2021) therefore does not make it possible to use all the flexibility and robustness offered by PLC/RF hybridisation. It is desirable to overcome these various drawbacks of the prior art. It is in particular desirable to propose a transmission method that makes it possible to improve the robustness to errors of such a hybrid communication network. DISCLOSURE OF THE INVENTION At least one embodiment relates to a transmission method for transmitting data from a first node device to a second node device belonging to a network neighbourhood of said first node device, said first and second node devices belonging to an electrical supply network and being configured for transmitting said data by powerline and by radio frequency. The method comprises the following steps performed by said first node device: distributing the data in two groups of data by an operation of interlacing said data, each group being associated with a communication medium from powerline and radio frequency, andtransmitting each data item to a MAC layer of the communication medium associated with the group to which said data item belongs. Advantageously, robustness to errors is improved by interlacing the data that are distributed between the various communication media. According to a particular embodiment, the method furthermore comprises encoding the data by a Reed-Solomon encoder. The step of distributing the data in two groups of data by an operation of interlacing said data applies to the encoded data. According to a particular embodiment, distributing the data in two groups of data by an operation of interlacing said data comprises: generatin