Dual-protocol optoelectronic interface

Abstract

An optoelectronic interface (2) comprising: - a bandpass filter to the input of which the incoming light signals are applied, and arranged to produce filtered light signals, the bandpass filter being designed to allow the passage of all wavelengths of the signal carrying the plurality of predefined communication protocols; - a photoreceptor (12); - a processing unit (6) arranged to select a particular software module associated with the particular communication protocol (33p), from among a plurality of different software modules (33a, 33b) each associated with one of the predefined communication protocols. Figure from the summary: Fig. 1

Description

Title of the invention: Dual-protocol optoelectronic interface

[0001] The invention relates to the field of optoelectronic interfaces.

[0002] BACKGROUND

[0003] Internet gateways are known which are equipped with a fiber optic communication interface intended to be connected to a PON (Passive Optical Network).

[0004] PON-type optical fiber access networks are based on the transport of various information streams in a single optical fiber. These different information streams are generated and injected from upstream and / or downstream of the access network by means of monochromatic laser sources and are differentiated by the wavelength of the light signals carrying the information of the stream to be transported.

[0005] Historically, G-PON access technology was deployed around 2015, offering downstream speeds (from the core network to the user's terminal) of 2.5 Gbps and upstream speeds (from the user's terminal to the core network) of 1.25 Gbps. Then, starting in 2020, XGS-PON access technology was added to certain networks, offering symmetrical speeds of 10 Gbps, thus allowing an operator to offer different performance levels to its subscribers.

[0006] The G-PON (Gigabit-capable Passive Optical Network) access network defined by ITU-T Recommendation G.984.2 (“ITU-T G.984.2 - Gigabit-capable Passive Optical Networks (G-PON): Physical Media Dependent (PMD) lease specification of the International Telecommunication Union (ITU), Recommendation ITU-T G.984.2 Ed 2.0, Sep. 2019) implements a downstream flow for which the wavelength of the carrier signal is 1490 nm, as well as an upstream flow for which the wavelength of the carrier signal is 1310 nm.

[0007] The XGS-PON access network (for 10 Gigabit Symmetric Passive Optical Network), defined by ITU-T Recommendation G.9807.1 (ITU-T G.9807.1 (2016) Amd. 2, Edition 1.3, “10-Gigabit-capable symmetric passive optical network (XGS-PON) - Amendment 2.” International Telecommunication Union (ITU), Oct. 29, 2020), implements a downstream flow for which the wavelength of the carrier signal is 1577 nm, as well as an upstream flow for which the wavelength of the carrier signal is 1270 nm.

[0008] Recently, two new access networks have been defined by standardization bodies, and share a nascent market for very high-speed access networks.

[0009] The 25GS-PON (for 25 Gigabit Symmetric Passive Optical Network) access network defined by the MSA GROUP 25GS-PON Specification standard (25GS-PON Specification, 3.0, “25GS-PON Specification - 25 Gigabit Symmetric Passive Optical Network. ” Nov. 02, 2023. [Online]. Available: www.25gspon-msa.org), implements a downstream flow for which the wavelength of the carrier signal is 1358 nm, as well as an upstream flow for which the wavelength of the carrier signal can take three optional values.

[0010] The 50G-PON (for 50 Gigabit Passive Optical Network) access network defined by the ITU-T G.9804.3 standard (ITU-T G.9804.3 (2021) Amd. 2 (03 / 2024), Ed. 1.2, “50-Gigabit-capable passive optical networks (50GPON): Physical media dependent (PMD) rent specification Amendment 2. ” International Telecommunication Union (ITU), Mar. 22, 2024), implements a downstream flow for which the carrier signal wavelength is 1342 nm, as well as an upstream flow for which the carrier signal wavelength can take the same three optional values.

[0011] These two new technologies share characteristics for their information modulation scheme in NRZ (for Non Retum Zero), as well as their upstream flow rate of 25 Gbps (Gigabits per second).

[0012] The major difference between these two access networks lies in the downstream flow rate: 25 Gbps for 25GS-PON and 50 Gbps for 50G-PON, as well as in the wavelengths of the carrier signals of these downstream signals.

[0013] A characteristic of these two access networks is that they are based on the implementation of upstream carrier signals sharing the same optional wavelengths.

[0014] The three wavelength options for the upstream light signal allow for various coexistence solutions with previous access technologies G-PON and XGS-PON.

[0015] The first variant, named UW0 for 25GS-PON and Option 1 for 50G-PON, implements an upstream carrier signal with a wavelength of 1270 nm, which allows coexistence with a G-PON access network.

[0016] The second variant, named UW1 for 25GS-PON and Option 2 for 50G-PON, implements an upstream carrier signal with a wavelength of 1300 nm, which allows coexistence with an XGS-PON access network.

[0017] The third variant, named UW3 for 25GS-PON and Option 3 for 50G-PON, implements an upstream carrier signal with a wavelength of 1286 nm, which allows simultaneous coexistence with a G-PON access network and with an XGS-PON access network.

[0018] The industry focuses primarily on the third variant which offers the best coexistence coverage.

[0019] The two next-generation technologies are based on similar wavelengths to ensure coexistence with upstream flows from previous generations previous ones, but they are directly competitive, and they are in no way designed to coexist on the same fiber optic distribution network.

[0020] The gateway manufacturer is therefore faced with the following problem.

[0021] The optoelectronic interface of its gateways connected to a network using 25GS-PON technology must be able to receive light signals defined according to the protocol of the 25GS-PON technology, while the optoelectronic interface of its gateways connected to a network using 50G-PON technology must be able to receive light signals defined according to the protocol of the 50G-PON technology.

[0022] It therefore seems very advantageous to design a single optoelectronic interface that is natively functional with either version of the new access technology.

[0023] It is known, within the framework of PON fiber optic interfaces intended to operate with multiple optical access networks, to use a QOSA (Quadri-directional Optical Sub Assembly) type optical subassembly adapted to the two wavelength pairs of each protocol, and to associate with it two transmit and receive amplification chains whose processor accesses are selected according to a triggering element. However, such a QOSA component is complex to implement and requires the deployment of two complete communication chains.

[0024] OBJECT

[0025] The invention aims to reduce the complexity and cost of an optoelectronic interface compatible with several communication protocols.

[0026] SUMMARY

[0027] To achieve this goal, an optoelectronic interface is proposed, arranged to be connected to an optical fiber along which incoming light signals can travel, including specific light signals defined according to a single specific communication protocol from among a plurality of predefined communication protocols, each using a different carrier signal wavelength, the optoelectronic interface comprising:

[0028] - a bandpass filter at the input of which the incoming light signals are applied, and arranged to produce filtered light signals, the bandpass filter being designed to allow all wavelengths of the signal carrying the plurality of predefined communication protocols to pass through;

[0029] - a photoreceptor arranged to produce incoming electrical signals from the filtered light signals;

[0030] - a processing unit arranged to acquire incoming electrical signals, select a specific software module associated with the specific communication protocol, from among a plurality of different software modules, each associated with one predefined communication protocols, and interpret incoming electrical signals using said particular software module.

[0031] The bandpass filter is therefore designed to allow the passage of specific light signals associated with all predefined communication protocols. The processing unit then acquires the incoming electrical signals produced from these specific light signals and selects the specific software module associated with the particular communication protocol actually present on the network. The optoelectronic interface is thus compatible with all predefined communication protocols, so that the equipment (a gateway, for example) can be connected to any network on which any of these predefined communication protocols is used, even if the protocol in use is not known at the time of the gateway's design and manufacture.The optoelectronic interface requires a single receiving chain, which simplifies the optoelectronic interface and reduces its design and manufacturing costs.

[0032] An optoelectronic interface as previously described is further proposed, in which, for selecting the particular software module, the processing unit is arranged to:

[0033] - at startup of the optoelectronic interface, use an initial software module among the plurality of different software modules;

[0034] - attempt to interpret the incoming electrical signals with the initial software module;

[0035] - in case of failure, attempt to interpret the incoming electrical signals with another software module;

[0036] - repeat these steps until the incoming electrical signals can be interpreted with a suitable software module, the particular software module being said suitable software module.

[0037] An optoelectronic interface as previously described is further proposed, in which the processing unit includes a detection module arranged to analyze target signals from incoming electrical signals and to produce a detection signal representative of the particular communication protocol of the particular light signals,

[0038] the processing unit being arranged to select the particular software module according to the detection signal.

[0039] An optoelectronic interface as previously described is further proposed, comprising in addition a receiver processing component connected to an output of the photoreceptor and arranged to produce a presence signal having a predefined value when a level of the filtered light signals received by the photoreceptor is greater than a predefined threshold, and wherein the processing unit is arranged to select the particular software module based on a combination of the detection signal and the presence signal.

[0040] An optoelectronic interface as previously described is further proposed, in which the detection module includes at least one detector arranged to detect an energy level of at least one predefined electrical frequency, each predefined electrical frequency being associated with one of the predefined communication protocols.

[0041] We further propose an optoelectronic interface as previously described, in which the detection module is arranged to perform a correlation operation between the target signals, and one or more reference signals each associated with one of the predefined communication protocols.

[0042] We further propose an optoelectronic interface as previously described, in which a bandpass filter response curve includes, for each carrier signal wavelength associated with a predefined communication protocol, a local maximum covering said carrier signal wavelength.

[0043] We further propose an optoelectronic interface such as previously described, in which the response curve includes, between two successive local maxima, a substantially constant portion having an amplitude substantially equal to that of the local maxima.

[0044] An optoelectronic interface as previously described is further proposed, comprising also a light source arranged to emit outgoing light signals onto the optical fiber, a coupling element and a splitter blade positioned between, on the one hand, the optical fiber, and on the other hand, the light source and the photoreceptor,

[0045] the light source, the photoreceptor, the coupling element, the beam splitter and the bandpass filter being integrated into the same optoelectronic component.

[0046] An optoelectronic interface as previously described is further proposed, comprising also a light source arranged to emit outgoing light signals onto the optical fiber, a coupling element and a splitter blade positioned between, on the one hand, the optical fiber, and on the other hand, the light source and the photoreceptor,

[0047] the light source, the photoreceptor, the coupling element, the beam splitter being integrated into the same optoelectronic component,

[0048] the optoelectronic interface further comprising a Bragg grating forming the bandpass filter and an isolator, the Bragg grating and the isolator being located outside and upstream of said optoelectronic component.

[0049] We further propose equipment integrating an optoelectronic interface as previously described.

[0050] Equipment is also proposed as previously described, the equipment being an Internet gateway arranged to be connected to a PON network.

[0051] A configuration method is further proposed, implemented in a processing unit of an optoelectronic interface as previously described, and comprising the steps of acquiring the incoming electrical signals, selecting a particular software module associated with the particular communication protocol, from among a plurality of different software modules each associated with one of the predefined communication protocols, and interpreting the incoming electrical signals using said particular software module.

[0052] A computer program is further proposed comprising instructions which lead the processing unit of the optoelectronic interface as previously described to execute the steps of the configuration process as previously described.

[0053] A computer-readable recording medium is also proposed, on which the computer program as previously described is recorded.

[0054] The invention will be better understood in the light of the following description of particular, non-limiting embodiments of the invention. Brief description of the drawings

[0055] Reference will be made to the attached drawings, among which:

[0056] [Fig-1] [Fig. 1] represents a gateway comprising an optoelectronic interface according to a first embodiment;

[0057] [Fig.2] [Fig.2] represents an optoelectronic subset;

[0058] [Fig.3] [Fig.3] represents a response curve of a bandpass filter according to a first embodiment;

[0059] [Fig.4] [Fig.4] represents a response curve of a bandpass filter according to a second embodiment;

[0060] [Fig.5] [Fig.5] represents a gateway comprising an optoelectronic interface according to a second embodiment;

[0061] [Fig.6] [Fig.6] represents steps of a configuration process implemented in the gateway. DETAILED DESCRIPTION

[0062] In the description that follows, identical, similar or analogous elements will be designated by the same reference numerals.

[0063] With reference to Figures 1 and 2, the Internet gateway 1 comprises an optoelectronic interface 2 according to a first embodiment. This optoelectronic interface 2 is connected to an optical fiber 3 of a PON network 4.

[0064] The optoelectronic interface 2 allows the gateway 1 to transmit outgoing light signals Sk to the network (downstream to upstream communication) and to receive incoming light signals Sie from the network 4 (upstream to downstream communication).

[0065] The incoming light signals Sie, originating from the network 4 and traveling along the optical fiber 3, comprise specific light signals Sip, which are defined respectively according to a single specific communication protocol from among a plurality of predefined communication protocols. The incoming light signals Sie may therefore include: • either only the specific Sip light signals, • either the particular light signals Sipainsi than other light signals which are not defined according to one of the predefined communication protocols.

[0066] Here, the plurality of predefined communication protocols includes two possible protocols: that associated with the 25GS-PON access network technology and that associated with the 50G-PON access network technology.

[0067] The design of gateway 1 allows it to cooperate with a single and any protocol among these two protocols which, it should be recalled, are competing: only one of these two protocols is present on network 4. The particular communication protocol, actually present on optical fiber 3, is not known at the time of the design and manufacture of gateway 1.

[0068] The optoelectronic interface 2 comprises an optoelectronic subset 5 and a processing unit 6.

[0069] The optoelectronic subassembly 5 is bidirectional and is here integrated into a single optoelectronic component 7 of the BOSA type (for Bidirectional Optical Sub Assembly).

[0070] The optoelectronic subassembly 5 comprises an emitting device including a light source 8, a coupling element 9, a beam splitter 10, a bandpass filter 11 and a receiving device including a photoreceptor 12.

[0071] The coupling element 9 and the separating blade 10 are positioned between, on the one hand, the optical fiber 3 (upstream side), and on the other hand, the light source 8 and the photoreceptor 12 (downstream side).

[0072] The light source 8 is here, for example, a "laser" source, and for example, a laser diode. The laser diode 8 emits the outgoing light signals Sk, in the form of monochromatic optical signals, towards the optical fiber 3. The outgoing light signals Sk are emitted by the laser diode 8 onto the optical fiber 3 via the beam splitter 10 and the coupling element 9.

[0073] Coupling element 9 is: - adapted to the transmission of outgoing light signals Sk received from the laser diode 8 in an airborne propagation space to the core of the optical fiber 3 so that they are directed upstream of the optical network 4; - and adapted to the transmission to an airborne propagation space of incoming light signals Sie from the core of the optical fiber 3 coming from upstream of the optical network 4.

[0074] The separating blade 10 is oriented in such a way that its reflective face can direct the incoming light signals Sie received from the coupling element 9 towards the sensitive surface of the photoreceptor 12 and that its absorbing face can allow the outgoing light signals Sk generated by the laser diode 8 to pass to the coupling element 9.

[0075] The incoming light signals Sie are applied to the input of the bandpass filter 11 via the coupling element 9 and the separating blade 10.

[0076] The bandpass filter 11 produces filtered light signals Sif from the incoming light signals Sie.

[0077] The photoreceptor 12 of the receiving device includes a photodiode. The photodiode 12 receives the filtered light signals Sif and generates incoming electrical signals See, images of the filtered light signals Sif that it receives.

[0078] Since a photodiode is by nature almost agnostic to the energy of the photons that strike it, and therefore to the wavelength of the light signal received from upstream of the optical network, it is customary to insert in the optical receiving path a filter such as filter 11. This precaution makes it possible to select an optical signal from among a plurality of signals potentially present on the optical network.

[0079] The BOSA component used is, for example, the BOSA model PB630005 from the supplier POTRON (registered trademark), which allows interfacing with a 50G-PON type access network. This component consists of: - a laser source adapted to emit at a rate of 25 Gbps a monochromatic light signal whose wavelength is 1286 nm corresponding to option 3 of the 50G-PON technology and to option UW3 of 25GS-PON; - a photoreceptor adapted to receive at a maximum rate of 50 Gbps a light signal in the O and E bands of infrared signals (1260 -1460 nm); - of a receiving bandpass filter whose bandwidth window covers the wavelength range 1330 - 1356 nm defined by ITU-T Recommendation G.9804.3 in chapter 10.1.

[0080] Here, however, as has been understood, gateway 1 is capable of receiving particular light signals Si p which are defined according to a single particular communication protocol (not known a priori) among a plurality of predefined communication protocols each using a different carrier signal wavelength.

[0081] The incoming light signals Sie, including the particular light signals Si p, are therefore applied to the input of the bandpass filter 11.

[0082] Here, the original BOSA component has been modified. The bandpass filter 11 has been modified and is now adapted to allow the transmission of all carrier signal wavelengths from the plurality of predefined communication protocols. Here, the bandpass filter 11 is therefore designed to allow the transmission of wavelengths 1342 nm and 1358 nm.

[0083] The idea was therefore conceived to adapt the original BOSA component to also operate with 25GS-PON technology by modifying the filter window 11 to allow it to also pass light signals downstream of the 25GS-PON technology, whose wavelength is 1258 nm as defined in the MSA GROUP 25GS-PON Specification in Figure Bl

[0084] This adjustment can be achieved using a method known to those skilled in the art in the field of optical filtering, which consists of adjusting the composition and structure of the thin films deposited on the surface of the glass plate composing the bandpass filter 11.

[0085] Advantageously, the pass window of the filter 11 must cover the wavelength range 1330 - 1380 nm so that the photodiode 12 is sensitive to optical signals received from upstream for both technologies.

[0086] With reference to [Fig.3], the response curve 25 of the bandpass filter 11 includes, for each carrier signal wavelength associated with a predefined communication protocol, a local maximum 26a, 26b covering said carrier signal wavelength.

[0087] The response curve 25 of the bandpass filter 11 therefore includes a first local maximum 26a covering the band 1342 + / - 2nm and a second local maximum 26b covering the band 1358 + / - 2nm.

[0088] This bandpass filter ensures compatibility in reception with optical signals in the downstream direction of 25GS-PON and 50G-PON technologies.

[0089] Template 19 shows a first window covering the signal band downstream of the 50G-PON technology for which the filter must exhibit a minimum reference attenuation. This attenuation, corresponding to the substantially constant portion, is ideally equal to a few tenths of a dB.

[0090] Template 20 shows a second window covering the signal band downstream of the 25GS-PON technology for which the filter must also show a minimum reference attenuation.

[0091] The substantially constant portion 17 of the response curve therefore covers all the wavelengths of the carrier signal of all the predefined communication protocols: here the 1342 + / - 2nm band and the 1358 + / - 2nm band.

[0092] Template 21 shows the minimum wavelength and attenuation boundary that the filter 11 must apply to the signal passing through it for the lower part of the spectrum. This boundary corresponds here to the lower boundary shown by ITU-T Recommendation G.9804.3 in Chapter 10.1.

[0093] Template 22 shows the minimum wavelength and attenuation boundary that the filter 11 must apply to the signal passing through it for the upper part of the spectrum. This boundary corresponds here to the upper boundary shown in the MSA GROUP 25GS-PON Specification in Figure Bl

[0094] The response curve 25 of the filter conforms to the definition of templates 19, 20, 21 and 22.

[0095] With reference to [Fig.4], the response curve 15 of the filter 11 according to a second embodiment includes, between two successive local maxima, a substantially constant portion 17 having an amplitude substantially equal to that of the local maxima.

[0096] The response curve 15 therefore includes an increasing portion 16, followed by the substantially constant portion 17, followed by a decreasing portion 18.

[0097] The response curve 15 of the filter 11 is again in accordance with the definition of templates 19, 20, 21 and 22.

[0098] This bandpass filtering principle described here in the context of the 25GS-PON and 50G-PON protocols can be applied to any other pair or set of protocols for which it would be advantageous to share the photoreceptor. In this case, it is necessary to define the window(s) to allow the passage of light signals downstream corresponding to each of the protocols, while blocking unwanted signals.

[0099] Here, as we have seen, the light source 8, the photoreceptor 12, the coupling element 9, the separating blade 10 and the bandpass filter 11 are integrated into the same optoelectronic component 7. This configuration is not mandatory.

[0100] The bandpass filter 11 could for example be located outside the optoelectronic component 7, which then integrates only the light source 8, the photoreceptor 12, the coupling element 9 and the separating blade 10.

[0101] The bandpass filter 11 is then positioned upstream of the optoelectronic component 7, in series on the optical fiber 3.

[0102] This configuration complicates the implementation by requiring an additional component. Indeed, the filter, as positioned in front of the photoreceptor in [Fig. 2], naturally blocks photons transmitted by the laser diode 8 that would otherwise be reflected by an element of the access network. This blocking function is crucial to avoid disturbing the photodiode 12, which is sensitive to a very broad spectrum.

[0103] If it were to be placed outside the component 7, the bandpass filter 11 should also allow the outgoing light signals Sk produced by the laser diode 8 to pass upstream while blocking any reflections from upstream.

[0104] The bandpass filter 11, in this configuration, includes, for example, a Bragg grating. The optoelectronic interface 2 further includes an optical isolator to block spurious signals resulting from reflections of the outgoing light signals. The Bragg grating and the isolator are located outside and upstream of the optoelectronic component 7.

[0105] The processing unit 6 (electronic and software), for its part, includes at least one processing component 30, which is for example a "general-purpose" processor, a processor specializing in signal processing (or DSP, for Digital Signal Processor), a processor specializing in artificial intelligence algorithms (of the NPU type, for Neural Processing Unit), a microcontroller, or a programmable logic circuit such as an FPGA (for Field Programmable Gate Arrays) or an ASIC (for Application Specified Integrated Circuit).

[0106] The processing component 30 is here a processor called the "main processor".

[0107] The processing unit 6 also includes one or more memories 31, connected to or integrated into the processing component 30. At least one of these memories 31 forms a computer-readable recording medium, on which is recorded at least one computer program comprising instructions which lead the processing component 30 to execute at least some of the steps of the configuration process which will be described.

[0108] The main processor 30 is responsible for the generation and decoding of the electrical signals implemented in the optoelectronic interface 2. It is also responsible for the execution of the software necessary for the implementation of this interface, and, in particular, it is responsible for the protocol aspect according to the selected access network technology.

[0109] Several different software modules 33, each responsible for a distinct predefined communication protocol, are stored in memory 31 and are capable of being executed by the main processor 30. Each software module 33 is therefore associated with a single distinct predefined communication protocol and is capable of interpreting (only) the incoming electrical signals See from the signals specific lighting conditions. If p is defined according to said distinct predefined communication protocol.

[0110] There are therefore at least two software modules stored in memory 31: a software module 33a associated with the 25GS-PON technology protocol and a software module 33b associated with the 50G-PON technology protocol.

[0111] The processing unit 6 further comprises a (single) transmission chain 35 and a (single) reception chain 36.

[0112] The emission chain 35 includes a laser driver component 37, which includes an adjustable amplifier and is connected to the laser diode 8. The laser driver component 37 is located here outside the optoelectronic component 5.

[0113] Thus, in the downstream-upstream direction, the software module responsible for implementing the interface with the access network defines a set of outgoing digital signals Sns, which are generated by a specific electrical interface of the processor 30 to be converted into outgoing light signals Sk for transmission upstream of the access network. These outgoing digital signals Sns are shaped by the laser driver component 37, which is driven by the processor 30 via control signals Sci. The analog electrical signals Sea, shaped by the laser driver component 37, are injected into the laser diode 8 integrated into the optoelectronic component 7 (BOSA), to be converted to produce the outgoing light signals Sk, which are transmitted upstream through the optical fiber 3.

[0114] In the upstream-downstream direction, the incoming electrical signals See, images of the particular light signals Si p received from upstream, are generated by the photodiode 12 integrated into the optoelectronic component 7. These incoming electrical signals See, which are analog electrical signals, are converted into a set of incoming digital signals Sne by a receiver processing component 38 of the receiver chain 36, which is connected to an output of the photodiode 12. The receiver processing component 38 includes an adjustable shaping amplifier driven by the processor 30 via control signals Sc2. The incoming digital signals Sne, shaped by the receiver processing component 38, are injected into a specific electrical interface of the main processor 30 to be processed and interpreted by the software module.

[0115] The MALD-37035B model from MACOM (registered trademark) is an example of a laser driver component.

[0116] The MACOM company's MATP-056026 model is an example of a receiving processing component.

[0117] The BCM55050 model from BROADCOM (registered trademark) is an example of a main processor component.

[0118] In an implementation variant, it is possible to group the laser driver and the reception processing into a single component, for example the GN27L90 model from SEMTECH (registered trademark).

[0119] It is also possible to integrate the receiver processing component and / or the laser driver component into the processor.

[0120] The optoelectronic interface 2 therefore comprises a single transmission chain 35 and a single reception chain 36.

[0121] As we have seen, the bandpass filter 11 allows all wavelengths of the carrier signal of the plurality of predefined communication protocols to pass through, that is to say here the wavelengths of the 25GS-PON technology protocol and the 50G-PON technology protocol.

[0122] The optoelectronic interface 2 therefore allows the gateway 1 to operate according to either access network technology.

[0123] As we have seen, one of the technologies is present on network 4, and this technology is not known a priori by gateway 1, which is designed to be able to operate with both technologies. However, in order to function correctly, gateway 1 must use a software module 33 in charge of the protocol, which is adapted to the particular communication protocol of the particular light signals Si p.

[0124] This software module is implemented by the processing component 30 and it allows, in particular, the interpretation of incoming electrical signals See-

[0125] The processing unit 6 is arranged to acquire the incoming electrical signals See, select a particular software module 33p associated with the particular communication protocol, from among the plurality of different software modules 33, and interpret the incoming electrical signals See using said particular software module 33p.

[0126] In a first embodiment, to select the specific software module 33p, the processing unit 6 is arranged to:

[0127] - at the start-up of gateway 1 and therefore of optoelectronic interface 2, use a initial software module (which is for example software module 33a);

[0128] - attempt to interpret the incoming See electrical signals with the software module initial ;

[0129] - if this fails, attempt to interpret the incoming electrical signals with another software module (here software module 33b);

[0130] - repeat these steps until the electrical signals can be interpreted with a adapted software module, the particular software module 33p being said adapted software module.

[0131] In this embodiment, the software configuration is therefore predefined to be executed automatically when the gateway 1 is started. It can also be engaged by a subsequent configuration action followed by a restart of the gateway 1.

[0132] By default, when manufacturing gateway 1, the initial software module in charge of the protocol is for example associated with the 25GS-PON technology protocol (module 33a).

[0133] As soon as the processing unit 6 receives the incoming electrical signals See, from particular light signals Si p, it therefore attempts to interpret them with this software module.

[0134] If successful, the software module associated with the 25GS-PON technology protocol is retained and thus selected. Incoming electrical signals are interpreted using this particular software module.

[0135] In case of failure, the software module associated with the 50G-PON technology protocol is selected (software module 33b), then loaded and executed.

[0136] Of course, the initial software module in charge of the protocol could be the one associated with the 50G-PON technology protocol.

[0137] However, this operation requires a restart of gateway 1, which is restrictive.

[0138] It is also possible to place the management of the software module 33 responsible for the protocol in a standby position during the startup of gateway 1, and then launch a specific version based on a subsequent action. This alternative advantageously avoids a restart of the entire gateway 1 due to an initial selection incompatible with the technology of the access network 4 connected to interface 2.

[0139] To take advantage of this alternative, it is necessary to detect the presence of one or the other access network technology on the fiber 3 as soon as the latter is connected to the optoelectronic interface 2.

[0140] Since the photodiode 12 is indiscriminately sensitive to particular light signals Si p coming from either type of access network, it is necessary to exploit other signals to ensure the distinction and thus detect the presence of one or the other protocol.

[0141] In a second embodiment, with reference to [Fig. 5], the processing unit 6 comprises a detection module 40 arranged to analyze target signals from the incoming electrical signals See and to produce a detection signal Sd representative of the particular communication protocol of the light signals particulars Si p, the processing unit 6 being arranged to select the particular software module 33p according to the detection signal Sd.

[0142] The target signals are, for example, the incoming electrical signals See themselves, or the incoming digital signals Sn e. Here, in this case, the detection module 40 is connected to the photodiode 12 and the target signals are the incoming electrical signals See-

[0143] Here, "analyze the target signals" means:

[0144] - acquire the target signals;

[0145] - extract at least one predefined characteristic of the target signals, which is representative of the particular communication protocol of the particular light signals Sip from which the target signals originate.

[0146] The "analysis" can therefore be carried out on incoming analog or digital electrical signals.

[0147] Here, moreover, the receiver processing component 38 is arranged to produce a presence signal Sp having a predefined value when a level of the filtered light signals Sif received by the photodiode 12 is greater than a first predefined threshold. The first predefined threshold is, for example, equal to -30 dBm. The presence signal Sp thus makes it possible to detect the presence of particular light signals Sip, whose carrier signal wavelength is included within the bandwidth of the bandpass filter 11.

[0148] In one embodiment, the processing unit 6 is arranged to select the particular software module 33p according to a combination of the detection signal Sd and the presence signal Sp.

[0149] The presence signal Sp is here, for example, the LOS (Loss Of Signal) protocol signal. Indeed, a first level of directly usable information exists in the form of the LOS protocol signal produced by the receiver processing component. This digital LOS signal is in an active state as soon as no optical signal is received with a predefined and sufficient level by the photodiode 12, and therefore as soon as the level of the filtered light signals Sif received by the photodiode 12 is below a second predefined threshold. The second predefined threshold is, for example, equal to -35 dBm.

[0150] This same first level of directly usable information also exists in the form of the RX_SD (Reception Signal Detect) protocol signal produced by the reception processing component 38. This digital signal RX_SD is positioned in an active state as soon as an optical signal is received by the photodiode 12 with a sufficient predefined level.

[0151] Either, or a combination of, the LOS and / or RX_SD signals can be used to ensure the detection by the main processor 30 of particular light signals Si p which are received by the photodiode 12 and whose wavelength corresponds to the pass window of the bandpass filter IL

[0152] The two access network technologies are distinguished in the downstream direction by the raw rate of the received signal, and therefore by the frequency signature of the electrical signal at the output of the photodiode 12 or at the output of the receiving processing component 38, depending on whether the analog or digital signal is considered.

[0153] The 25GS-PON technology implements a downstream signal modulated in NRZ and clocked at a rate of 25 gigasymbols per second. This signal, either at the output of photodiode 12, converted into the electrical domain by photodiode 12, or at the output of the receiver processing component 38 after reshaping and normalization, therefore exhibits a spectral signature extending from low frequencies up to 12.5 GHz for the useful signal. Harmonics related to edge steepness are also present beyond this range, but the energy level is not significant.

[0154] The 50G-PON technology implements a downstream signal modulated in NRZ and clocked at a rate of 50 gigasymbols per second. This signal, either at the output of photodiode 12, converted into the electrical domain by photodiode 12, or at the output of the receive processing component 38 after reshaping and normalization, therefore exhibits a spectral signature extending from low frequencies up to 25 GHz for the useful signal. Harmonics related to edge steepness are also present beyond this range, but the energy level is not significant.

[0155] In a first alternative, the detection module 40 includes at least one detector arranged to detect an energy level of at least one predefined electrical frequency, each predefined electrical frequency being associated with one of the predefined communication protocols.

[0156] The radio frequency detector 40 here has a center frequency which is defined at 25 GHz for a bandwidth of about ten GHz.

[0157] The incoming electrical signals See, from the photodiode 12, and therefore analog, are applied to the input of the radio frequency detector 40 (and therefore to the input of its radio frequency part).

[0158] The radio frequency detector 40 produces a detection signal Sd (digital) which is representative of an energy level present in the incoming electrical signals See and related to the presence (or not) of a signal clocked at a rate of 50 Giga symbols per second.

[0159] The digital output of the detection module 40 is connected to a digital input of the processor 30. The latter can evaluate the presence of the signature showing the presence of a signal downstream of the 50G-PON technology. It should be noted that the detection module 40 can be integrated into the receive processing component 38, the processor 30, or take the form of a separate module (as is the case in [Fig.5]) acquiring the incoming electrical signals See at the output of the photodiode 12 or at the output of the receive processing component 38.

[0160] Alternatively, the detection module is arranged to perform a correlation operation between the target signals and one or more reference signals, each associated with one of the predefined communication protocols.

[0161] The digital output of the detection module is again connected to a digital input of the processor.

[0162] The correlation operation can thus be carried out between the target signals (which are for example the "real" incoming electrical signals, analog, or the incoming digital signals Sne)), and one or more typical reference signals which would be present in the same place in the case of the reception of a signal downstream according to at least one of the possible technologies.

[0163] Here, the reference signal corresponds to 50G-PON technology.

[0164] Again, the detection module 40 can be integrated into the receiving processing component 38, the processor 30, or take the form of a separate module (as is the case in [Fig.5]) acquiring the incoming electrical signals See at the output of the photodiode 12 or at the output of the receiving processing component 38.

[0165] Following the detection of the specific communication protocol of the specific light signals Si p, the processing unit 6 loads and executes the specific "correct" software module 33p, which corresponds to the specific light signals Si p actually present. Therefore, it is not necessary to restart the gateway 1.

[0166] It is thus possible, by a combination of the information available to the processor 30 such as the LOS signal present on the signals from the receiving processing component 38 and the signals from the detection module 40, to determine the presence of a signal showing a very high speed access network connected to the optoelectronic interface.

[0167] The table in the Annex shows an example of using these two signals to determine the presence of none, one, or the other access network technology on the fiber 3 connected to interface 2.

[0168] With reference to [Fig.6], a particular embodiment of the configuration process implemented by the processing unit 6 is described (using the presence signal Sp, here LOS signal, and the detection module 40, using the radio frequency detection technique of a signature of the 50G-PON technology).

[0169] Gateway 1 is powered on: step EL

[0170] The processor 30 initializes the reception chain 36 and in particular the reception processing component 38 so that it activates at least its LOS (Sp) signal detection function: step E2. The processing unit 6 acquires the presence signal Sp.

[0171] The processor 30 then waits for the deactivation of the LOS signal resulting from a sufficient downstream optical signal level at the interface input in a band encompassing 25GS-PON and 50G-PON technologies: step E3. The processing unit 6 acquires the incoming electrical signals See.

[0172] Once this signal is detected, the processor 30 is able to detect, via the detection signal Sd, the presence or absence of the signature of a downstream signal corresponding to the 50G-PON technology: step E4.

[0173] When this signal is inactive, then the processor 30 will be able to load the software module 33a corresponding to the protocol and physical management of a 25GS-PON type access interface: step E5.

[0174] Otherwise, the processor 30 loads the software module 33b corresponding to the protocol and physical management of a 50G-PON type access interface: step E6.

[0175] The processor 30 has thus selected and loaded the particular software module associated with the particular communication protocol.

[0176] After the loading of the specific software module 33p corresponding to the detected technology, the processor 30 will be able to start its execution and thus initiate its synchronization mechanism with the selected access network: step E7. The processor 30 interprets the incoming electrical signals using the specific software module.

[0177] Thus, according to one or more embodiments, by modifying the bandpass filter window and selecting a specific software module associated with the specific communication protocol, it is possible, during the gateway initialization phase, to determine, upon receiving a downstream signal, whether the gateway should configure itself for 50G-PON access or 25GS-PON access. This provides a cost-effective solution for the gateway to efficiently detect which type of access to use.

[0178] It is noted that the optoelectronic interface is particularly advantageous when the outgoing light signals use the same wavelength (thus allowing the use of a single laser diode for both protocols).

[0179] Of course, the invention is not limited to the embodiments described but encompasses any variant falling within the scope of the invention as defined by the claims.

[0180] The equipment in which the optoelectronic interface is integrated is not necessarily an Internet gateway. It could also be a simple ONU (for

[0181]

[0182]

[0183]

[0184]

[0185] An Optical Network Unit (ONU) is responsible for converting optical signals and processing them according to one of the protocols present on the optical network into a higher-level protocol such as IP (Internet Protocol) for use in third-party equipment such as an internet router or internet gateway. The connection between these two devices, the ONU and the router, can take the form of, for example, an Ethernet link. The optoelectronic component, which at least partially integrates the optoelectronic subassembly, is not necessarily a BOSA component. Other assemblies exist, such as the QOSA (Quadridirectional Optical Subassembly) or the TriOSA (Triple Optical Subassembly). These components, which can be used to implement at least part of the optoelectronic subassembly, are derived from the main BOSA structure as described and include several transmitting subassemblies adapted to as many monochromatic light signals, and / or several receiving subassemblies also adapted, through different filters, to as many monochromatic light signals that can coexist in the same optical array. The number of predefined communication protocols that may be present on the network could be different from two. The optoelectronic interface is capable of operating with all types of PON protocols as long as the incoming light signals Sie are likely to be within the window of the bandpass filter 11. In one or more embodiments, a plurality of predefined communication protocols may be present on the optical fiber, this plurality comprising N protocols with N>2. The detection module is configured to detect a subset of the plurality of protocols, this subset comprising Nl protocol(s) from the plurality of protocols. The detection module is further configured to treat the Sp signal as an indication of the detection of the protocol, referred to as the "last protocol," not belonging to said subset. In one example, the detection module detects the last protocol by interpreting the LOS as detecting the last frequency of said last protocol. In one or more embodiments, the bandpass filter 11 is modified to be bandpassable for the operating frequencies of the plurality of N predefined communication protocols. In one example, the different templates of the bandpass filter 11 are adapted to the bandwidths of the N predefined protocols. Appendix Signal Sp Signal Sd High-Speed ​​Network Status ACTIVE INACTIVE Absent INACTIVE INACTIVE 25GS-PON Network Present INACTIVE ACTIVE 50G-PON Network present

Claims

Demands

1. Optoelectronic interface (2), arranged to be connected to an optical fiber (3) on which incoming light signals (Sie) can travel, comprising particular light signals (Si p) which are defined according to a single particular communication protocol from among a plurality of predefined communication protocols, each using a different carrier signal wavelength, the optoelectronic interface (2) comprising: - a bandpass filter (11) into whose input the incoming light signals (Sle) are applied, and arranged to produce filtered light signals (Sif), the bandpass filter being designed to allow all the carrier signal wavelengths of the plurality of predefined communication protocols to pass; - a photoreceptor (12) arranged to produce incoming electrical signals (See) from the filtered light signals (Sif);- a processing unit (6) arranged to acquire incoming electrical signals, select a particular software module associated with the particular communication protocol (33p), from among a plurality of different software modules (33a, 33b) each associated with one of the predefined communication protocols, and interpret the incoming electrical signals using said particular software module.

2. Optoelectronic interface according to claim 1, wherein, in order to select the particular software module (33p), the processing unit (6) is arranged to: - at startup of the optoelectronic interface (2), use an initial software module from among the plurality of different software modules (33a, 33b); - attempt to interpret the incoming electrical signals (See) with the initial software module; - in case of failure, attempt to interpret the incoming electrical signals with another software module; - repeat these steps until the incoming electrical signals are interpreted with a suitable software module, the particular software module (33p) being said suitable software module.

3. Optoelectronic interface according to claim 1, wherein the processing unit (6) comprises a detection module (40) arranged to analyze target signals from incoming electrical signals (See) and to produce a detection signal (Sd) representative of the particular communication protocol of particular light signals, the processing unit being arranged to select the particular software module (33p) according to the detection signal.

4. Optoelectronic interface according to claim 3, further comprising a receiver processing component (38) connected to an output of the photoreceptor (12) and arranged to produce a presence signal (Sp) having a predefined value when a level of the filtered light signals (Sif) received by the photoreceptor is greater than a predefined threshold, and wherein the processing unit is arranged to select the particular software module according to a combination of the detection signal (Sd) and the presence signal (Sp).

5. Optoelectronic interface according to any one of claims 3 or 4, wherein the detection module (40) comprises at least one detector arranged to detect an energy level of at least one predefined electrical frequency, each predefined electrical frequency being associated with one of the predefined communication protocols.

6. Optoelectronic interface according to any one of claims 3 or 4, wherein the detection module is arranged to perform a correlation operation between the target signals, and one or more reference signals each associated with one of the predefined communication protocols.

7. Optoelectronic interface according to any one of the preceding claims, wherein a response curve (15; 25) of the bandpass filter (11) comprises, for each carrier signal wavelength associated with a predefined communication protocol, a local maximum (26a, 26b) covering said carrier signal wavelength.

8. Optoelectronic interface according to claim 7, wherein the response curve (15) comprises, between two successive local maxima, a substantially constant portion (17) having an amplitude substantially equal to that of the local maxima.

9. Optoelectronic interface according to any one of the preceding claims, further comprising a light source (8) arranged to emit outgoing light signals (Sis) on the optical fiber (3), a coupling element (9) and a splitter blade (10) positioned between, on the one hand, the optical fiber (3), and on the other hand, the light source (8) and the photoreceptor (12), the light source, the photoreceptor, the coupling element, the splitter blade and the bandpass filter being integrated into the same optoelectronic component (7).

10. An optoelectronic interface according to any one of claims 1 to 8, further comprising a light source arranged (8) to emit outgoing light signals (Sk) onto the optical fiber (3), a coupling element (9) and a splitter blade (10) positioned between, on the one hand, the optical fiber (3), and on the other hand, the light source (8) and the photoreceptor (12), the light source, the photoreceptor, the coupling element, the splitter blade being integrated into the same optoelectronic component, the optoelectronic interface (2) further comprising a Bragg grating forming the bandpass filter and an isolator, the Bragg grating and the isolator being located outside and upstream of said optoelectronic component.

11. Equipment (1) incorporating an optoelectronic interface (2) according to one of the preceding claims.

12. Equipment according to claim 11, the equipment being an Internet gateway (1) arranged to be connected to a PON network (4).

13. A configuration method, implemented in a processing unit (6) of an optoelectronic interface (2) according to any one of claims 1 to 10, and comprising the steps of acquiring the incoming electrical signals (See), selecting a particular software module (33p) associated with the particular communication protocol, from among a plurality of different software modules each associated with one of the predefined communication protocols, and interpreting the incoming electrical signals using said particular software module.

14. Computer program comprising instructions that cause the processing unit (6) of the optoelectronic interface (2) according to any one of claims 1 to 10 to perform the steps of the configuration process according to claim 13.

15. Computer-readable recording medium on which the computer program according to claim 14 is recorded.

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