Light detection circuit
Patent Information
- Application Number
- PCT/EP2025/057721
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-03-20
- Publication Date
- 2026-09-24
Smart Images
Figure EP2025057721_24092026_PF_FP_ABST
Abstract
Description
[0001] LIGHT DETECTION CIRCUIT
[0002] Technical Field
[0003] The present disclosure relates to a light detection circuit, a device for use with the optical detection circuit, and a method for detecting a data signal in at least one fiber optic cable as implemented by the light detection circuit.
[0004] Background
[0005] A radio access network (RAN) is a major component of a wireless telecommunications system that connects individual devices to other parts of a network through a radio link. The use of light signals (also often referred to as “optical signals”, irrespective of the light wavelength used) as transferred through one or more fiber optic cables is increasingly being implemented within RAN architecture in telecommunications networks. An optical fiber (sometimes referred to as an “optical fibre”), is a flexible glass or plastic fiber that can transmit light from one end to the other using the well-known phenomena of internal reflections of a light signal within a solid core of the optical fiber. A fiber-optic cable (also known as an “optical-fiber cable”) is an assembly similar to an electrical cable but contains one or more optical fibers that are used to carry light signals.
[0006] Fiber optic cables offer many advantages over conventional copper cables, such as high bandwidth and low latency, which makes them important for transferring large amount of data needed for future generations of wireless technology (e.g., 6G networks). Fiberoptic cables are also typically more immune to interference when compared to copper cables (e.g., are not susceptible to electromagnetic interference, ensuring signal integrity) and can offer greater flexibility in different interconnection scenarios (e.g., different types of fiber optic cables can be used depending on the specific network requirements and deployment scenario). Fiber optic cables are typically used in three main areas if RAN architecture, the “fronthaul”, the “midhaul” (or “mid-haul”), and the “backhaul”. Fronthaul refers to the front-end interface, while backhaul refers to the back end. Midhaul refers to an architectural link with between backhaul and fronthaul of the RAN, such as for example, between the O-RAN Distributed Unit (O-DU) and the O-RAN Central Unit (O-CU).
[0007] Wavelength Division Multiplexing (WDM) is an optical networking technology that allows for an expansion of the capacity of an optical fiber by adding a multiplexer and a demultiplexer at each end of the fiber. This enables multiple data streams to betransmitted over different wavelengths of light through a single fiber (or fiber optic cable) simultaneously. In networking, "grey WDM" refers to a standard, single-channel optical transceiver that does not utilise specific wavelengths of light, unlike “coloured WDM”. In other words, grey WDM transmits data on a single "uncoloured" light source, often used for basic connections within a network where multiple wavelengths are not needed. In this context, "grey" refers to a lack of colour or specific wavelength used.
[0008] A passive optical network (PON) is a fiber-optic network that uses unpowered devices to deliver data to multiple users. PONs are often used by internet service providers (ISPs) to provide broadband to homes and businesses. Grey and coloured WDM optical networking technology are commonly used in PONs and mobile Fronthaul networks.
[0009] The transfer of electrical signals in the form of a net-flow of free electrons (or electrical current) through legacy RAN architecture (e.g., copper wires) is known to generate an electromagnetic (EM) field around the material through which the electrical signals flow in accordance with ‘Fleming's Right Hand Rule’. More specifically, generated EM field lines flow concentrically around the metal wire through which current flows. This EM field is readily detectable externally to the wires without any disruption of the electrical signal being carried within. On the other hand, light signals are instead made up of photons that are carried long distances through a core of the fiber optic cables. In this way, light signals are impossible to detect externally to the fiber optic cable they are being carried in. As such, legacy fiber-optic RAN architecture requires an intrusive monitoring to determine the presence of light signals being carried within the fiber core.
[0010] Intrusive monitoring of fiber optic cables can however cause significant disruption of the light signal being caried which can result in unwanted misconnections, disconnections (e.g., signal loss), and / or disruptions (e.g., increased signal latency and / or reduced bandwidth), all of which can be costly and inconvenient to remedy. The level of disruption is often independent of the wavelength of the light signal being carried and / or the type of WDM (i.e., grey or coloured) being used. The risks of causing unwanted disruptions are problematic for in-field engineers or installers that are required to determine the presence of light signals in fiber optic cables in order to successfully carry out their maintenance, installation, and / or network upgrade work.
[0011] Tunable transceivers are known to be used in the access and fronthaul network domains but are not viable in passive and cheap network solutions. Fully automated proceduresfor end-to-end (E2E) connectivity are therefore not viable in these contexts. The automatic tuning protocols work fine provided that the transmitting and receiving ports of a transceiver pair are coupled to the same wavelength port of the respective WDM multiplexer (mux) I demultiplexers (demux), however if a wrong port is connected (e.g., via human error), any auto-tuning protocols will fail since no E2E communication is setup. It may then be hard to determine what went wrong, which comes with an associated high time / cost of troubleshooting.
[0012] A known problem therefore exists in respect to the difficulty in-field engineers or installers experience in carrying out their work with fiber optic cables whilst also trying to mitigate against light signal disruptions.
[0013] Statements of Invention
[0014] It is an objective of present application to provide a practical apparatus and a method of detecting a presence of “live” light (or optical) signals carried in fiber optic cables, particularly in ports of a generic optical passive component or directly on a fiber optic connector. To achieve this result, a light detection circuit for using with at least one fiber optic cable, and a corresponding method for detecting a light signal, is proposed:
[0015] In a first aspect of the invention there is a light detection circuit, the detection circuit in optical connection with at least one fiber optic cable configured to carry a light signal; the detection circuit comprising:
[0016] at least one splitter in optical connection with the at least one fiber optic cable; at least one photodiode in optical connection with the at least one splitter;
[0017] a processor in electronic communication with the at least one photodiode; and a transceiver in electronic communication with the processor;
[0018] wherein the at least one splitter is configured to divert a percentage of light from the light signal to the at least one photodiode; the at least one photodiode configured to convert the percentage of light into at least one current, and further configured to transfer the at least one current to the processor,
[0019] wherein the processor is configured to determine, from the at least one current, a data signal associated with the at least one fiber optic cable, and the processor is further configured to transfer the data signal to the transceiver. The transceiver is configured to wirelessly transmit the data signal external to the detection circuit.In some embodiments, the above-mentioned detection circuit is for use with at least one fiber optic cable that may be incorporated into a connector or incorporated into each port of the passive optical component to provide the possibility to detect the presence of a light signal and then to add to the component an interface for an end-user (e.g., an infield engineer or installer).
[0020] Advantageously, the detection circuit apparatus allows an in-field-engineer / installer to easily identify, on a passive optical component or on single connectors, whether a light signal is present within the core of one or more fiber optic cables.
[0021] Further advantageously, the apparatus does not adversely affect the live traffic within these fiber optic cables and prevents any unwanted light signal disruption during installation or network upgrade works. The apparatus also helps in-field engineers / installers to more easily locate and verify correct fiber optic connections amongst a possible multitude of passive optical components. This invention is particularly useful in cases where the optical component is equipped in a remote passive site with respect to a Central Office (CO).
[0022] Other advantages are that the apparatus simplifies light signal detection processes and improves an ease of use for the end-user, thus simplifying maintenance, installation, and / or network upgrade carried out by in-field engineers or installers. This has the corollary effect of reducing time, effort, and costs whilst limiting the possibility of human errors being made.
[0023] The detection circuit is small, low-cost, and flexibly implemented (e.g., used on different connectors in different passive optical components). Any additional circuitry can be adapted on connectors making it usable on all hardware by only changing the connector. In this way, the detection circuit is easily compatible with the hardware of any type of legacy optical equipment component, such as any type of passive optical component hardware (e.g., a port, a connector, etc). This is because an implementation or deployment of the detection circuit only requires an installation of a new fiber optic cable (or optical cable) with a connector that includes the detection circuit’s functionality. There is therefore no requirement of any modification of the existing hardware in the legacy optical equipment for the detection circuit to be deployed.In an embodiment, the data signal may be a binary signal deterministic of either i) a signal present in the at least one fiber optic cable or ii) no signal present in the at least one fiber optic cable.
[0024] In some embodiments, the processor may be any type of ‘control logic’, such as microcontroller, computer processing unit (CPU), or controller. In some embodiments, the processor may have an internal (built-in) memory or may instead be connected to a local memory (e.g., a processor with access to a memory as part of the light detection circuit). In these embodiments the processor is required to register and store the binary signal deterministic of either i) a signal present in the at least one fiber optic cable or ii) no signal present in the at least one fiber optic cable. In this embodiment, the binary state (i.e., “0” or “1” state) is recordable onto the internal memory for reference at any point in time afters is recorded.
[0025] Alternatively, the processor has no requirement for an internal (built-in) memory or even access to a memory. Advantageously, in this embodiment the processor is not required to register and / or store the binary signal deterministic of either i) a signal present in the at least one fiber optic cable or ii) no signal present in the at least one fiber optic cable. This is because the processor is configured to determine, from the at least one current (which can be calculated as a voltage signal, using the known relationship of: Voltage = Current (I)* Resistance (R), or V=IR), a data signal associated with the at least one fiber optic cable. In this embodiment, the data signal can be thought of simply as voltage signal (Vout) which is reflective of a binary state (i.e., “0” or “1” state). In other words, the at least one current is determined as a binary voltage signal which is recognised by the processor of the light detection circuit to be deterministic of either i) a signal present in the at least one fiber optic cable or ii) no signal present in the at least one fiber optic cable.
[0026] In some embodiments, the electrical connection between all circuit components with the light detection circuits is via electrically conductive wires. In other embodiments the electrical connection is any type of connection, such as circuit wire connections (e.g., soldered connections), wire-to-board connections, and / or board-to-board connections.In other embodiments, the diverted percentage of light may be at least 5% of the light signal carried in the at least one fiber optic cable.
[0027] The at least one splitter may be configured to divert a percentage of light (of the light signal carried in the at least one fiber optic cable) as low as possible to reduce attenuation on the light signal path and, at the same time, high enough to ensure, in all operating conditions, a level of the light signal power higher than the sensitivity of the at least one photodiode (PD).
[0028] In some embodiments, the diverted percentage of light may be any percentage of light value (of the light signal carried in the at least one fiber optic cable) in a range between 5% to 10% (inclusive of the 5% and 10% benchmarks). This percentage range has been found to be acceptable in terms of attenuation introduced by the splitters and is sufficient in most operating conditions required of the light detection circuit. This particular percentage range has been optimised to factor in the sensitivity of any photodiodes (PD) in use, the transmitted power, any fiber attenuation of the light signal, and typical distances from the optical transceiver.
[0029] In other embodiments, the diverted percentage of light may be any integer or non-integer percentage of light value (of the light signal carried in the at least one fiber optic cable) that is any percentage value between 5% to 10% (inclusive of the 5% and 10% benchmarks), such as 6% to 9%, for example 7% and 8%.
[0030] In some embodiments, the transceiver may operate by one short-range wireless technology such as using: Bluetooth, Wi-Fi, NearLink, near-field communication (NFC), or Zigbee. Alternatively, the transceiver may operate using a combination of two or more different short-range wireless technologies.
[0031] In a preferred embodiment, the transceiver may be an NFC-tag, and wherein the NFC-tag is configured to be inductively powered by an electromagnetic signal external to the detection circuit.
[0032] NFC is a short-range wireless technology, and NFC-tag / NFC-reader couples typically operate within 4 centimetres (1.5 inches) of each other. Advantageously, this short range requires a very low power consumption (typically less than approximately 50mW) and prevents unwanted interception of data.Further advantageously, as the NFC-tag in the light detection circuit is powered by an electromagnetic signal external to the detection circuit (i.e., is supplied by the NFC-reader), no internal power supply (e.g., batteries) is required. This advantageously reduces manufacturing, and maintenance costs and simplifies serviceability.
[0033] In another embodiment, the detection circuit may further comprise at least one lightemitting diode (LED) in electronic communication with the processor and the NFC-tag; wherein the at least one light-emitting diode may be further configured to receive electrical power from the NFC-tag when the NFC is inductively powered by an electromagnetic signal external to the detection circuit.
[0034] Advantageously, the electrical power induced by the NFC-reader by electromagnetic (EM) induction in the NFC-tag is sufficient to alternatively power and illuminate one or more dedicated LEDs within the detection circuit.
[0035] As an alternative to powering the NFC-tag / NFC-reader couple, the power produced by the EM field of the NFC-reader instead powers one or more LEDs within an optical passive component or directly on a fiber optic connector.
[0036] In an embodiment, the binary signal may be a voltage signal.
[0037] In another embodiment, the voltage signal that is deterministic of i) a signal present in the at least one fiber optic cable may be a first voltage signal of 2.55V.
[0038] In an embodiment, the voltage signal that is deterministic of ii) no signal present in the at least one fiber optic cable may be a second voltage signal of 1 ,3V.
[0039] In embodiment of the invention, there may be a “high level” voltage instead of 2.55V and a “low level” voltage of 1 ,3V. Alternatively, there may be a voltage signal threshold of 2.55V above the chosen voltage threshold, while the second voltage signal is below the voltage threshold.
[0040] In another embodiment, the least one light-emitting diode (LED) in electronic communication with the processor may be configured to be electrically powered by the first voltage signal only.In a second aspect of the invention there is a user device for use with the detection circuit of the previous statements; wherein the user device comprises: a receiver and a display. The receiver is in electronic communication with the display and is configured to wirelessly receive the data signal from the detection circuit, at the receiver, and display the data signal on the display.
[0041] In some embodiments, the user device is a purpose-built hand-held device. In other embodiments, the user device is any portable smart-device, such as a smartphone, a laptop, personal computer, and / or any smart-wearable (e.g., smartwatch, smart band, smart glasses, etc.).
[0042] In an embodiment, the receiver of the user device may be an NFC-reader configured to generate the electromagnetic signal to inductively power the NFC-tag in the light detection circuit.
[0043] In another embodiment, the display may comprise a graphical user interface (GUI).
[0044] Advantageously, the GUI interface can clearly display the results of the light signal detection with no ambiguity. In an example embodiment, instead of the illumination of one or more LEDs, the GUI may display unambiguous words indicative of a detected light signal e.g., the GUI displays the words “No signal detected” or “Signal detected”.
[0045] In another embodiment, the graphical user interface may be generated by at least one application (or “app”) installed on a memory of the user device.
[0046] Advantageously, an end user (e.g., in-field engineers) of the user device can determine the result of the light signal detection directly via an app. The app may be a pre-installed firmware available for the user device. Alternatively, the app maybe be made available on a public sever (e.g., via the internet) and downloadable for multi-platform uses.
[0047] In an example embodiment, the user device may be a smartphone with an NFC-reader already built into the hardware. In this embodiment, the app may be downloadable via the internet (e.g., ‘Google Play Store’ for an Android platform, ‘Apple Store’ for an iPhone Operating System (iOS) platform).In a third aspect of the invention, there is a method for detecting a data signal in at least one fiber optic cable, where the method implemented by the detection circuit of the previous statements and comprising the following steps:
[0048] - the at least one splitter diverting the percentage of light from the signal to the at least one photodiode;
[0049] - the at least one photodiode converting the percentage of light into the voltage, and transferring the voltage to the processor,
[0050] - the processor determining, from the voltage, the data signal associated with the at least one fiber optic cable,
[0051] - the processor transferring the data signal to the transceiver, and
[0052] - the transceiver wirelessly transmitting the data signal external of the detection circuit.
[0053] In an embodiment, the data signal may be a binary signal deterministic of either i) a signal present in the at least one fiber optic cable or ii) no signal present in the at least one fiber optic cable.
[0054] In another embodiment, the binary signal may be indicated, external to the detection circuit, by an illumination of the at least one light-emitting diode.
[0055] In an embodiment, the binary signal may be wirelessly received from the detection circuit of the previous statements, at the receiver of the user device of the previous statements, and wherein the binary signal may be displayed on the display of the user device.
[0056] Brief description of the drawings
[0057] For a better understanding of the techniques, and to show how they may be put into effect, reference will now be made, by way of example, to the accompanying drawings, in which:
[0058] Figures 1 illustrates a light detection circuit and a user device according to an embodiment of the invention;
[0059] Figure 2 illustrates a light detection circuit and a user device according to another embodiment of the invention;Figure 3 illustrates a light detection circuit comprising LEDs, and a user device, according to an embodiment of the invention;
[0060] Figure 4 illustrates a light detection circuit interfaced with an optical passive component, and a user device, according to an embodiment of the invention;
[0061] Figure 5 illustrates a light detection circuit interfaced with an optical passive component in communication with the user device according to an embodiment of the invention;
[0062] Figure 6 illustrates a circuit diagram comprising two circuits;
[0063] Figure 7 is a flow diagram illustrating method steps carried out by a method of detection according to an aspect of the invention.
[0064] Detailed
[0065]
[0066] Generally, all terms used herein are to be interpreted according to their ordinary meaning in the relevant technical field, unless a different meaning is clearly given and / or is implied from the context in which it is used. All references to a / an / the element, apparatus, component, means, step, etc. are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. The steps of any methods disclosed herein do not have to be performed in the exact order disclosed, unless a step is explicitly described as following or preceding another step and / or where it is implicit that a step must follow or precede another step.
[0067] Reference throughout the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the present solution. Thus, the appearance of the phrases “in one embodiment” or “in an embodiment” in various places throughout the specification are not necessarily all referring to the same embodiment. Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments. Any feature of any of the embodiments disclosed herein may be applied to any other embodiment, wherever appropriate. Likewise, any advantage of any of the embodiments may apply to any otherembodiments, and vice versa. Other objectives, features and advantages of the enclosed embodiments will be apparent from the following description.
[0068] Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Other embodiments, however, are contained within the scope of the subject-matter disclosed herein, the disclosed subject-matter should not be construed as limited to only the embodiments set forth herein; rather, these embodiments are provided by way of example to convey the scope of the subject-matter to those skilled in the art.
[0069] Figure 1 illustrates a light detection circuit 100 (interchangeably referred to as a “detection circuit”) according to a first aspect of the invention. Referring to Figure 1, the detection circuit 100 is in optical connection with two separate fiber optic cables configured to carry separate light signals; a first fiber optic cable 114 and a second fiber optic cable 116, hereafter collectively referred to as the fiber optic cables 114, 116. The detection circuit 100 comprises at least one splitter (also referred to as a “beam splitter”) in optical connection with the fiber optic cables 114, 116. A first splitter 102a is in optical connection with fiber optic cable 114 and a second splitter 102b is in optical connection with fiber optic cable 116.
[0070] Each splitter (collectively referred to a as “splitters” 102a, 102b) is in the optical path of the fiber optic cables 114, 116 which allows them to divert (sometimes referred to as splitting, siphoning, and / or tapping the light) a percentage of the total light signal carried within the fiber optic cables 114, 116 towards one or more photodiodes “PDs” (sometimes also referred to as photodetectors) within the detection circuit 100. In this way, PDs 104a, 104b in the detection circuit 100 are in optical connection with the splitters 102a, 102b. The detection circuit 100 further includes a processor 108 in electronic communication with the PDs 104a, 104b and a transceiver 112 in electronic communication with the processor 112.
[0071] In an example use scenario, the detection circuit 100 is optically interfaced with a port, such as for example, a port belonging to a connector in a passive component (or any generic optical passive component). The port includes the fiber optic cables 114, 116 which carry light signals and are therefore not part of the detection circuit 100.
[0072] The fiber optic cables 114, 116 each comprise a core containing one or more optical fibers (not shown in the figures). It is the optical fibers within the core of the fiber opticcables 114, 116 that carry a light signal in any direction within that cable, and where each optical fiber (in the fiber optic cables 114, 116) is in a signal isolation from each other. The arrow heads on the fiberoptic cables 114, 116 indicate a direction of travel of each light signal carried such that, as shown in Figure 1, the light signal carried in fiber optic cable 116 (by one or more of the optical fibers contained in that cable 116) travels in a direction opposite to that off the light signal carried in fiber optic cable 114 (by one or more of the optical fibers contained in that cable 114). The direction of travel of the light signals within the fiber optic cables 114, 116 shown in Figure 1 is exemplary and for illustrative purposes only. In other embodiments, the direction of travel of the light signals carried within the two fiber optic cables 114, 116 may be the same as each other. In an example embodiment of the detection circuit 100, the optical cables 114, 116 each comprise a core containing two optical fibers (not labelled in the figures), where each optical fiber is in signal isolation from each other. In this embodiment, fiber optic cable 114 includes two optical fibers which each carry a light signal in opposite directions (TX / RX) to each other. Similarly, fiber optic cable 116 includes two optical fibers which each carry a light signal in opposite directions (TX / RX) to each other.
[0073] Referring to Figure 1, splitter 102a diverts a percentage of light 114’ from the total light signal carried in fiber optic cable 114 towards PD 104a. Similarly, splitter 102b diverts a percentage of light 116’ from the total light signal carried in fiber optic cable 116 towards PD 104b. The diverted percentages of light 114’, 116’ can also be referred to as “portions” of light. The diverted percentage of light 114’, 116’ is at least 5% of the light signal carried in the fiber optic cables 114, 116.
[0074] PDs are known to generate electrical energy from light energy using the known phenomena of the photoelectric effect, where photons of light striking a semiconductor material within the PD creates electron-hole pairs, which are then separated by the electric field within the diode's depletion region, resulting in a measurable electrical current that increases with the intensity of light. In the example use scenario of the detection circuit 100, upon receipt of the percentage of light 114’, PD 104a converts the incident percentage of light 114’ into a first current 106a (which can also be measured as a first voltage). Similarly, upon receipt of the percentage of light 116’, PD 104b converts the incident percentage of light 116’ into a second current 106b (which can also be measured as a second voltage). In an example embodiment, the PDs referred to throughout are any type of InGaAs PIN photodiodes.The PDs 104a, 104b are configured to transfer the generated currents 106a, 106b to the processor 108 by an electrical connection (not shown). In some embodiments, the electrical connection is an electrically conductive wire (not shown), in other embodiments the electrical connection is any type of connection, such as circuit wire connections (e.g., soldered connections), wire-to-board connections, and / or board-to-board connections. The processor 108 is configured to determine, from the generated currents 106a, 106b (or equivalently, the generated voltages), a data signal 110 associated with the at least one fiber optic cable 114, 116. In this way, the data signal 110 collectively refers to the signal of data associated with both fiber optic cables 114, 116 and which is transferred between the processor 108 and the transceiver 112.
[0075] The processor 108 is further configured to transfer the data signal 110 by an electrical connection to a transceiver 112. In some embodiments, the electrical connection refers to one or more electrically conductive wires (not shown in the figures), in other embodiments the electrical connection is any type of connection, such as circuit wire connections (e.g., soldered connections), wire-to-board connections, and / or board-to-board connections.
[0076] The processor 108 computes or calculates a voltage value using the known relationship between voltage and current, namely: V=I*R, whereby the processor 108 factors in a known internal resistance (R) value as a mathematical constant. The processor 108 determines a data signal 110 associated with the fiber optic cables 114, 116. In this embodiment, the data signal is a voltage signal (Vout) which is, itself, indicative of a binary state or binary signal (i.e., a “0” or “1” data signal) of fiber optic cables 114,116. The generated currents 106a, 106b are converted into binary voltage signals Vout which are calculated by the processor 108 of the light detection circuit 100 to be deterministic of either i) a signal present in the at least one fiber optic cable 114, 116 or ii) no signal present in the at least one fiber optic cable 114, 116.
[0077] In the embodiment shown in Figure 1 , the data signal 110 is a wired connection between the processor 108 and the transceiver 112 comprising two individual wires (not labelled in the figures). The two individual wires are hereafter referred to as a first wire and a second wire. In this embodiment, the first wire carries a part of the data signal 110 which is associated with fiber optic cable 114 and the second wire carries a part of the data signal 100 associated with fiber optic cable 116.Example: In an example use scenario of the detection circuit 100, fiber optic cable 114 is not be carrying any light signal, whereas fiber optic cable 116 is carrying a light signal. In this scenario, the processor 108 determines a first voltage signal Vout indicative of no light signal being present, and a second voltage signal Vout indicative of a light signal being present. The first voltage signal Vout is determined to be zero (or zero volts, 0V) for fiber optic cable 114 which is determined as a binary data signal 110 of “0” indicating a light signal is not present in fiber optic cable 114. In contrast, the processor 108 determines the second voltage signal Vout to be any non-zero value for fiber optic cable 116 which is determined as a binary data signal 110 of “1” indicating that a light signal is present in fiber optic cable 116. The processor 108 electronically sends a data signal 110 to the transceiver 112 along both a first wire and a second wire. The first wire carries a part of the data signal 110 which is associated with fiber optic cable 114, namely the binary data signal 110 of “0” indicating a light signal is not present in fiber optic cable 114. Simultaneously, the second wire carries a part of the data signal 110 associated with fiber optic cable 116, namely a binary data signal 110 of “1” indicating a light signal is present in fiber optic cable 114. The transceiver 112 received the data signal 110 from both the first wire and second wire, for transmission externally.
[0078] In some embodiments of the invention, there are non-zero voltage thresholds. In this embodiment, a non-zero voltage threshold of 1.3V is deterministic of a light signal not being present in the fiber optic cables 114, 116. In this way, if the measured voltage value Vout is a voltage signal (VPOS_OFF) that is, or falls below, 1 ,3V, this is indicative of a light signal not being present in the fiber optic cables 114, 116. The voltage signal (VPOS_OFF) is therefore a “low” threshold voltage value of 1 ,3V.
[0079] In other embodiments, another non-zero voltage threshold is 2.55V and is deterministic of a light signal being present in the fiber optic cables 114, 116. In this way, if the measured voltage value Vout is a voltage signal (VPOS_OFF) that is, or exceeds, 2.55V, this is indicative of a light signal being present in the fiber optic cables 114, 116. In this way, the voltage signal (VPOS_ON) is a minimum voltage value of 2.55V.
[0080] The transceiver 112 is configured to wirelessly transmit the data signal 110, as received from the processor 108, externally of the detection circuit 100. In other embodiments, the transceiver 112 may transmit the data signal 110 by a wired connection. In alternative embodiments, the transceiver 112 may be a transmitter only, with no wireless receiving capabilities.In the embodiment shown in Figure 1, the transceiver 112 transmits the data signal 110 wirelessly, externally to the light detection circuit 100, to be received by a user device 120 which has its own receiver (not shown). The user device 120 is illustrated as a held-held device, which may be piece of dedicated equipment supplied to an end-user (e.g., installer). For example, the light detection circuit 100 can be integrated / adapted in generic fiber connectors, due to the compactness, and is particularly relevant for the radio equipment practice where it can be implemented within the FullAXS optical connector.
[0081] In other embodiments, the user device 120 is a is a smart device 120 (e.g. a smartphone) with a built-in display 124. The display 124 indicates information contained in the received data signal 110 (i.e., a binary signal deterministic of either i) a signal present in the at least one fiber optic cables 114, 116 or ii) no signal present in the at least one fiber optic cable 114, 116). As illustrated in Figure 1, the display 124 visually indicates a presence of a light data signal in the fiberoptic cables 114, 116 via a GUI (i.e., displaying the text “Yes” per numbered fiber optic cables). Alternatively, or additionally, the data signal 110 may be audibly indicated by the user device 120 to the end-user (e.g., via a buzzer or a loudspeaker). Advantageously, an end-user can easily determine from the user device 120 which port and / or optical fiber a light signal is present in and act accordingly (e.g., removing the correct fibers according to the maintenance operation to perform).
[0082] Figure 2 illustrates a light detection circuit 200 that is identical to light detection circuit 100 shown in Figure 1, with the exception for the inclusion of a different type of user device 220 which generates and transmits a wireless signal 222.
[0083] For completeness, when the embodiment shown in Figure 2 is in use, a splitter 202a diverts a percentage of light 214’ from the total light signal carried in fiberoptic cable 214 towards PD 204a. Similarly, a splitter 202b diverts a percentage of light 216’ from the total light signal carried in fiber optic cable 216 towards PD 204b. PD 204a converts the incident percentage of light 214’ into a first current 206a (which can also be measured as a first voltage). Similarly, upon receipt of the percentage of light 216’, PD 204b converts the incident percentage of light 216’ into a second current 206b (which can also be measured as a second voltage).A processor 208 is configured to determine, from the generated currents 206a, 206b (or equivalently, the generated voltages), a data signal 210 associated with the at least one fiber optic cable 214, 216. The processor 208 transfers the data signal 210 by an electrical connection to a transceiver 212. The transceiver 212 of the light detection circuit 200 is an NFC-tag 212 comprising one or more induction coils 223, and the user device is an NFC-reader 220 which generates an electromagnetic (EM) field (as indicated by concentric dashed lines of the wireless signal 222). The EM field 222 is generated a distance away from the light detection circuit 200 which can be any known working distance of NFC-tag / reader couples (typically approximately 4 centimetres (cm)). One induction coil 223 is shown in this embodiment for illustrative purposes, although more than one coil may be used in the NFC-tag 212. In some embodiments, the electrical connection is an electrically conductive wire (not shown), in other embodiments the electrical connection is any type of connection, such as circuit wire connections (e.g., soldered connections), wire-to-board connections, and / or board-to-board connections.
[0084] The NFC-tag 212 is configured to wirelessly transmit the data signal 210 external of the detection circuit 200 by using the power inductively generated by the EM field 222 of the NFC-reader 220. The data signal 210 is sent out, externally to the light detection circuit 200, to be received by an NFC-reader 220 which has its own in-built receiver (not shown). The NFC-reader 220 subsequently receives the data signal 210 sent from the NFC-tag 212 where the data signal 210 contains the information contained in the received data signal 210 (i.e., a binary signal deterministic of either i) a signal present in the at least one fiber optic cables 214, 216 or ii) no signal present in the at least one fiber optic cable 214, 216). As shown in Figure 2, the NFC-reader 220 has a display 224 that displays the result of information contained in the data signal 210. In this way, the transfer of the data signal 210 between the NFC-tag 212 and the NFC-reader 220 is an NFC communication link whereby information or data is transferred between the two.
[0085] As illustrated in Figure 2, the display 224 visually indicates a presence of a light data signal in the fiber optic cables 214, 216 via a GUI (i.e., displaying the text “Yes” per numbered fiber optic cables). Alternatively, or additionally, the data signal 210 may be audibly indicated by the user device 220 to the end-user (e.g., via a buzzer or a loudspeaker). The NFC-reader may be part of a held-held device, which may be piece of dedicated equipment supplied to an end-user (e.g., radio equipment where it can be implemented within the FullAXS optical connector).In other embodiments, the user device 220 is a smart device 220 (e.g. a smartphone) with a built-in display 224 and built-in NFC capabilities (e.g., a built-in NFC-reader and / or NFC-tag). In this embodiment, a GUI interface of the display 224 is generated by at least one application (app) installed on a memory (not shown) of the smart device 220. The NFC-tag 212 of the light detection circuit 200 is placed on board of a passive optical connector) or on board of a passive optical component (both not shown in Figure 2) optically interfaced with the light detection circuit 200 of Figure 2.
[0086] The light detection circuit 200 is powered by an NFC-reader 220 / NFC-tag 212 coupling. When the NFC-reader 220 queries the NFC-Tag 212, the NFC-tag 212 acquires sufficient energy to detect the presence of a light signal on each fiber optic cable 214, 216 almost instantaneously (and no later than in a few seconds). In other words, the detection circuit 200 harvests electrical power inductively generated at a coil 223 belonging to the NFC-tag 212 by the EM field 222 generated by the NFC-reader 220. This detection circuit 200 therefore consumes an electrical power as low as few milliwatts (mW) which is compatible with the power provided by the NFC-reader 220.
[0087] Advantageously, the provides a detection circuit 200 that can readily harvest electrical power (energy) via the NFC-reader 220 / NFC-tag 212 coupling, removing the need for any internal power supply (e.g., batteries). The detection circuit 220 therefore has a very low power consumption and low running cost, and has other associated benefits, such as reduced manufacturing, and maintenance costs and simplified serviceability.
[0088] Figure 3 illustrates a light detection circuit 300 which is an alternative embodiment to light detection circuit 200 shown in Figure 2. Figure 3 illustrates the inclusion of light emitting diodes (LEDs) 330, 330’ as part of the light detection circuit 300, but is otherwise the same as the light detection circuit 200 embodiment shown in Figure 2.
[0089] The LEDs 330,330’ provide an alternative mechanism for displaying information to an end-user (i.e., alternative to a data signal communication between the NFC-tag and NFC-reader and the information being displayed on a user device). Instead, the data signal (or voltage signal Vout) is used to directly power (illuminate) the LEDs 330,330’ to visually indicate the presence of light signals in the fiber optic cables.
[0090] In the embodiment shown in Figure 3, the illumination of the LEDs 330, 330’ indicates the presence of a light signal in the fiber optic cables 314, 316. The non-illumination ofthe LEDs 330, 330’ indicates the non-presence (or lack) of a light signal in the fiber optic cables 314, 316. Although two LEDs 330, 330’ are shown in Figure 3, this is exemplary and for illustrative purposes only. In other embodiments, there may only be one LED included. In other embodiments, more than two LEDs 330, 330’ (up to any number) maybe be included in the light detection circuit 300, for example, one LED per fiber optic cable of the light detection circuit 300. Referring to Figure 3, LED 330 is associated with fiber optic cable 316 and LED 330’ is associated with fiber optic cable 314.
[0091] When the embodiment shown in Figure 3 is in use, splitter 302a diverts a percentage of light 314’ from the total light signal carried in fiber optic cable 314 towards PD 304a. Similarly, splitter 302b diverts a percentage of light 316’ from the total light signal carried in fiber optic cable 316 towards PD 304b. The diverted percentage of light 314’, 316’ is at least 5% of the light signal carried in the fiber optic cables 314, 316. The PDs 304a, 304b are configured to transfer the generated currents 306a, 306b to the processor 308 by an electrical connection (not shown). In some embodiments, the electrical connection is an electrically conductive wire (not shown), in other embodiments the electrical connection is any type of connection, such as circuit wire connections (e.g., soldered connections), wire-to-board connections, and / or board-to-board connections.
[0092] The processor 308 is configured to determine, from the generated currents 306a, 306b (or equivalently, the generated voltages), a data signal 310 associated with the at least one fiber optic cable 314, 316. The processor 308 determines a data signal 310 associated with the fiber optic cables 314, 316. In this embodiment, the data signal is a voltage signal (Vout) which is, itself, indicative of a binary state or binary signal (i.e., a “0” or “1” data signal) of fiber optic cables 314, 316. The generated currents 306a, 306b are converted into binary voltage signals Vout which are calculated by the processor 308 of the light detection circuit 300 to be deterministic of either i) a signal present in the at least one fiber optic cable 314, 316 or ii) no signal present in the at least one fiber optic cable 314, 316.
[0093] In an embodiment shown in Figure 3, the processor 308 transfers the data signal 310 by an electrical connection to a transceiver 312 (indicated by a dashed-line arrow from the processor 308 to the transceiver 312). The transceiver 312 of the light detection circuit 300 is an NFC-tag 312 comprising one or more induction coils 323, and the user device is an NFC-reader 320 which generates an electromagnetic (EM) field (as indicated by concentric dashed lines of the wireless signal 322). The EM field 322 isgenerated a distance away from the light detection circuit 300 which can be any known working distance of NFC-tag / reader couples (typically approximately 4 centimetres (cm)). One induction coil 323 is shown in this embodiment for illustrative purposes, although more than one coil may be used in the NFC-tag 312.
[0094] As the data signal 310 is a voltage signal (Vout), the transceiver 312 is configured to transfer the voltages to the LEDs 330, 330’ (as indicated by a dashed-line arrow from the transceiver 312 to LEDs 330, 330’). In the embodiment illustrated in Figure 3, the voltage signals Vout generated by the processor 308 are electrically connected (not shown in the figures) to the one or more LEDs 330, 330’ within the light detection circuit 330. In this way, when the processor 308 determines non-zero voltage signals Vout indicative of the presence of light signals, the Vout is instead used to powerthe LEDs 330, 330’. This is possible as the electrical power used to power the NFC-reader 320 / NFC-tag couple 312 is sufficient to instead powerthe one or more LEDs 330, 330’ momentarily when PDs 304a, 304b detect a light signals present in the fiber optic cables 314, 316.
[0095] In an alternative embodiment (also indicated in Figure 3), the data signal 310 (or voltage signal, Vout) is instead directly transferred from the processor 308 to the LEDs 330, 330’ (i.e., without the data signal 310 needing to travel via the transceiver 312). This embodiment is indicated by a solid-line arrow from the processor 308 to the LEDs 330, 330’. In this way, when the processor 308 determines non-zero voltage signals Vout indicative of the presence of light signals, the Vout is instead used to directly power and illuminate the LEDs 330, 330’ momentarily when PDs 304a, 304b detect a light signals present in the fiber optic cables 314, 316.
[0096] A measured voltage that is deterministic of a signal present in the at least one fiber optic cable 314, 316 is a first voltage signal (VPOS_ON) of 2.55V. A measured voltage value that is deterministic of no signal present in the at least one fiber optic cable 314, 316 is a second voltage signal (VPOS_OFF) of 1.3V. Preferably, the minimum level of light power that will be considered as indicative of a light signal being “present” (or live”) in the fiberoptic cables 314, 316 is-36dBm (approximately 250nW). This value results from a 5% tapping of a received signal of -20 dBm (typical of current transceivers dynamic range) with 3 dB of added margin.
[0097] Example: In an example use scenario of the detection circuit 300 shown in Figure 3, fiber optic cable 314 is not be carrying any light signal, whereas fiber optic cable 316 iscarrying a light signal. In this scenario, the processor 308 determines a voltage signal Vout value of zero (or zero Volts) for fiber optic cable 314. Consequently, no power is provided to associated LED 330’ and it fails to illuminate, visually indicating to an enduser that no light signal is present in that fiber optic cable. In contrast, the processor 308 determines a non-zero voltage signal Vout for fiber optic cable 316 which is used to power associated LED 330 visually indicating to an end-user a light signal is present in that fiber optic cable.
[0098] Advantageously, from the simple illumination of certain LEDs, an end-user can easily determine which port and / or optical fiber a light signal is present in and act accordingly (e.g., removing the correct fibers according to the maintenance operation to perform).
[0099] Figure 4 illustrates a light detection circuit 400 that is otherwise identical to light detection circuit 200 shown in Figure 2, but further illustrates the inclusion of any number of N fiber optic cables (or optical fibers), i.e., 414, 416....414N, 416N for N number, where N is any integer value of fiber optic cables that can be interfaced with that light detection circuit 400. For example, the light detection circuit 400 is interfaced with a passive optical component which contains multiple fiber optic cables.
[0100] For completeness, when the embodiment shown in Figure 4 is in use, a splitter 402a diverts a percentage of light 416’ from the total light signal carried in fiber optic cable 416 towards PD 404a. Similarly, splitter 402b diverts a percentage of light 414’ from the total light signal carried in fiber optic cable 414 towards PD 404b. PD 404a converts the incident percentage of light 416’ into a first current 406a (which can also be measured as a first voltage). Similarly, upon receipt of the percentage of light 414’, PD 404b converts the incident percentage of light 414’ into a second current 406b (which can also be measured as a second voltage).
[0101] A processor 408 is configured to determine, from the generated currents 406a, 406b (or equivalently, the generated voltages), a data signal 410 associated with the at least one fiber optic cable 414, 416. The processor 408 transfers the data signal 410 by an electrical connection to a transceiver 412. The transceiver 412 of the light detection circuit 400 is an NFC-tag 412 comprising one or more induction coils 423, and the user device is an NFC-reader 420 which generates an electromagnetic (EM) field (as indicated by concentric dashed lines of the wireless signal 422). The EM field 422 is generated a distance away from the light detection circuit 400 which can be any knownworking distance of NFC-tag / reader couples (typically approximately 4 centimeters (cm)). One induction coil 423 is shown in this embodiment for illustrative purposes, although more than one coil may be used in the NFC-tag 412.
[0102] As shown in Figure 4, the NFC-reader 420 has a display 424 that displays the result of information contained in the data signal 410 that the transceiver 422 transmits, externally to the light detection circuit 400, to be received by a NFC-reader 420 which has its own receiver (not shown), i.e., a binary signal deterministic of either i) a signal present in the at least one fiber optic cables 414, 416 or ii) no signal present in the at least one fiber optic cable 414, 416. The NFC-reader 420 may be part of a held-held device, which may be piece of dedicated equipment supplied to an end-user (e.g., radio equipment where it can be implemented within the FullAXS optical connector).
[0103] In other embodiments, the user device 420 is a smart device 420 (e.g. a smartphone) with a built-in display 424 and built-in NFC capabilities (e.g., a built-in NFC-reader and / or NFC-tag). In this embodiment, a GUI interface of the display 424 is generated by at least one application (app) installed on a memory (not shown) of the smart device 420. The NFC-tag 412 of the light detection circuit 400. Alternatively, the NFC-tag 412 may be placed elsewhere, such as on board of a passive optical component / connector414 (not shown in Figure 4).
[0104] Figure 5 illustrates a light detection circuit 500 which includes a passive optical component 540 according to an example embodiment. The light detection circuit 500 is similar to the light detection circuit 400 shown in Figure 4, however this embodiment includes a passive optical component 500 which has an interface comprising three interface modules 532a, 532b, and 532c. Each of the three interface modules 532a, 532b, 532c comprise four fiber optic cable ports 534 (of which only one is annotated in Figure 5). In this way, the light detection circuit 500 includes a passive optical component 500 with twelve fiber optic cable ports 534 in total (i.e., numbered “1” to “12” as labelled in Figure 5). Each of the twelve fiber optic cable ports 534 are connected to (or optically interfaced with) a single fiber optic cable (now shown), such that are 12 fiber optic cables connected to (or optically interfaced with) the passive optical component 540 of the detection circuit 500. Figure 5 is exemplary and for illustrative purposes only. In other embodiments of the light detection circuit 500, the passive optical component 540 may have any number of fiber optic cable ports 534 (more or less than the amount shown inFigure 5) which are correspondingly connected to (or optically interfaced with) a same number of fiber optic cables.
[0105] The light detection circuit 500 further includes an NFC-tag 512 comprising an induction coil 523 which communicates with an NFC-reader 520 which generates an electromagnetic (EM) field (as indicated by concentric dashed lines of the wireless signal 522). The EM field 522 is generated a distance away from the light detection circuit 500 which can be any known working distance of NFC-tag / reader couples (typically approximately 4 centimeters (cm)). One induction coil 523 is shown in this embodiment for illustrative purposes, although more than one coil may be used in the NFC-tag 512. A separate NFC-reader 520 has a display 524 that displays the result of information contained in the data signal 510 that the transceiver 522 transmits, externally to the light detection circuit 500, to be received by a NFC-reader 520 which has its own receiver (not shown), i.e., a binary signal deterministic of either i) a signal present in the fiberoptic cables (not shown) or ii) no signal present in the fiber optic cables . The display 524 visually indicates a presence of a light data signal in the fiber optic cables via a GUI interface (i.e., displaying the text “Yes” per numbered fiber optic cables, as illustrated in Figure 5).
[0106] The passive optical component 540 additionally includes one or more LEDs. In the embodiment shown in Figure 5, the passive optical component includes twelve corresponding LEDs 530, i.e., one LED 530 associated per fiber optic cable or (equivalently) one LED per fiber optic cable port 534. In the embodiment shown in Figure 5, an illumination of the LEDs 530 (as indicated by the solid dark shading) can (additionally to information given on the display 524 on the user device 520) indicate the presence of a light signal in the fiber optic cables or (equivalently) in the fiber optic cable port 534. Similarly, the non (or lack) of illumination of the LEDs 530indicates the nonpresence (or lack) of a light signal in the fiber optic cables or (equivalently) in the fiber optic cable port 534.
[0107] Figure 6 shows a first circuit 600 and a second circuit 600’ in accordance with the present invention.
[0108] The first circuit 600 illustrates electronic circuit components of the embodiment of the light detection circuit as previously described and shown in Figure 2, where light detection circuit 200 is powered by an NFC-reader 220 / NFC-tag 212 coupling. The firstcircuit 600 is needed in all the embodiments described to “sense” the presence of a light signal inside one or more fiber optic cables.
[0109] The second circuit 600’ is an additional circuit to be used with circuit 600. Circuit 600’ is additionally needed for the embodiment described and shown in Figure 3 where the powering of LEDs 330, 330’ is an alternative mechanism for displaying information to an end-user (i.e., alternative to a data signal communication between the NFC-tag and NFC-reader and the information being displayed on a user device). Second circuit 600’ illustrates electronic circuit components embodiment of the light detection circuit 300 which comprises one or more LEDs 330, 330’ and are represented by a single “LED D2” in circuit 600’ for illustrative purposes.
[0110] Referring to circuit 600, for ease of reference this circuit includes a PD (labelled “D1”). The circuit 600 further includes three resistors (labelled “R1”, “R2”, and “Rs”) and an operational amplifier (labelled “U1”). The circuit 600 represents a portion of the light detection circuit 200 shown in Figure 2.
[0111] Referring to Figures 2 and 6, circuit 600 collectively represents a first PD (i.e., PD 204a) a second PD (i.e., PD 204b) and the processor 208 of the light detection circuit 200 shown in Figure 2. The previously described fiber optic cables 214, 216, transceiver 212, processor 208, first splitter 202a and second splitter 202b are not shown in Figure 6. The first and second PDs (PD 204a and PD 204b) are collectively represented by the single PD “D1” in circuit 600 in Figure 6 for illustrative purposes.
[0112] The first PD 204a is in optical communication with the first splitter 202a that is in the optical path of the first fiber optical cable 214. Similarly, the second PD 204b is in optical communication with the second splitter 202b that is in the optical path of the second fiber optical cable 216. As indicated in circuit 600, the first splitter 202a diverts the first percentage 214’ of a total light signal onto the first PD 204a and the second splitter 202b diverts a second percentage 216’ of a total light signal onto the second PD 204b.
[0113] As previously described, the first and second PDs for each corresponding fiber optic cables transform the incident light detected (as diverted from the first and second splitters) into a binary signal deterministic of either i) a signal present in the at least one fiber optic cable or ii) no signal present in the at least one fiber optic cable.The processor 208 computes or calculates a voltage value using the known relationship between voltage and current, namely: V=I*R, whereby the processor factors in a known internal resistance (R) value as a mathematical constant. In circuit 600, the R = R1 + R2 + Rs. The processor subsequently determines a data signal 210 associated with the fiber optic cables. The data signal is a voltage signal (Vout) which is, itself, indicative of a binary state or binary signal (i.e., a “0” or “1” data signal) of fiber optic cables.
[0114] As previously described, the processor 208 transfers the data signal 210 by an electrical connection to a transceiver 212. The transceiver 212 of the light detection circuit 200 is an NFC-tag 212 comprising one or more induction coils 223, and the user device is an NFC-reader 220 which generates an electromagnetic (EM) field to read the NFC-tag 212 to determine the binary state or binary signal (i.e., a “0” or “1” data signal) of fiber optic cables.
[0115] According to an example embodiment, PD “D1” includes a current (l_D1 ON) of around 250nA assuming a photodiode responsivity close to 1 A / W.
[0116] Components dimensioning:
[0117] Rshunt at 60 °C > 30Mohm
[0118] |__D1OFF = Dark current =< 5nA
[0119] Rs = 10Mohm.
[0120] Current flowing through Rs with no light:
[0121] l_RSdark
[0122] LRSdark
[0123]
[0124] Voltage at U1 positive input with no light:
[0125] Vpos OFF—l_RSdark RS
[0126] Vpos_OFF "" 130nA* 10Mohm = 1.3V
[0127] Current flowing through Rs with -37dBm of optical power:
[0128] I_RSON=I_D1ON+l_D1 OFF
[0129] I_RSON = 250nA + 5nA = 255nA
[0130] Voltage at U1 positive input with light:
[0131] Vpos_
[0132] Vpos. _
[0133]
[0134] By choosing a voltage of 2.0V as threshold (i.e. with R1 = 33kohm and R2 = 22kohm) the output voltage Vout is “high” when the correspondent port is “live”. The presence oflight (U1 = “high”) for each optical fiber cable can be momentarily stored in the form of “1” and “0” in a register and reported to an ‘app’ as installed on any of the user devices 120, 220, 420, 320520 previously described (e.g., such as any smart device) or on the NFC-reader (e.g., NFC-reader 220) through the data-channel of the NFC protocol itself.
[0135] Figure 7 is a flow diagram that illustrates a method 1000 in accordance with an aspect of the invention. The method 1000 detects a data signal in at least one fiber optic cable as implemented by the detection circuits 100, 200, 300, 400 as previously described.
[0136] Referring to apparatus Figures 1 to 4 in conjunction with the flow-diagram of Figure 7, the method 1000 includes the following ordered steps (i.e., steps 1002 to 1010):
[0137] i. Step 1002: at least one splitter (102a, 102b; 202a, 202b; 302a, 302b; 402a, 402b) diverts a percentage of light (114’, 116’; 214’, 216’; 314’, 316’; 414’, 416’) from the signal to the at least one photodiode (104a, 104b; 204a, 204b; 304a, 304b; 404a, 404b).
[0138] ii. Step 1004: the at least one photodiode converts the percentage of light into a voltage and transfers the voltage to a processor (108, 208, 308, 408).
[0139] iii. Step 1006: the processor determines, from the voltage, a data signal (110, 210, 310, 410) associated with the at least one fiber optic cable (114, 116; 214, 216; 314, 316; 414, 416).
[0140] iv. Step 1008: the processor transfers the data signal to a transceiver (112, 212, 312, 412) and
[0141] v. Step 1010: the transceiver wirelessly transmits the data signal external to (i.e., outside of) the detection circuit (100, 200, 300, 400).
[0142] In an embodiment of the method 1000, the data signal is a binary signal deterministic of either i) a signal present in the at least one fiber optic cable or ii) no signal present in the at least one fiber optic cable. In another embodiment the binary signal is indicated, external to the detection circuit, by an illumination of the at least one lightemitting diode 330, 330’, 530.
[0143] In another embodiment, the binary signal is wirelessly received from the detection circuit 100, 200, 300, 400 (as previously described) at a receiver of the user device 120, 220, 320, 420 (as previously described). The binary signal is displayed on thedisplay 124, 224, 424 of the user device 120, 220, 420 or is displayed externally (e.g., via illuminated LEDs).
[0144] It should be noted that the above-mentioned embodiments illustrate rather than limit the idea, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. The word “comprising” does not exclude the presence of elements or steps other than those listed in a claim, “a” or “an” does not exclude a plurality, and a single processor or other unit may fulfil the functions of several units recited in the claims. Any reference signs in the claims shall not be construed so as to limit their scope.
Claims
27CLAIMS1. A light detection circuit (100, 200, 300, 400, 500), the detection circuit in optical connection with at least one fiber optic cable (114, 116) configured to carry a light signal;the detection circuit comprising:at least one splitter (102a, 102b) in optical connection with the at least one fiber optic cable (114, 116);at least one photodiode (104a, 104b) in optical connection with the at least one splitter (102a, 102b);a processor (108) in electronic communication with the at least one photodiode (104a, 104b); anda transceiver (112) in electronic communication with the processor (108); wherein the at least one splitter (102a, 102b) is configured to divert a percentage of light from the light signal to the at least one photodiode (104a, 104b); the at least one photodiode (104a, 104b) configured to convert the percentage of light into at least one current (106a, 106b), and further configured to transfer the at least one current (106a, 106b) to the processor (108);wherein the processor (108) is configured to determine, from the at least one current (106a, 106b), a data signal (110) associated with the at least one fiber optic cable (114, 116), and the processor (108) is further configured to transfer the data signal (110) to the transceiver (112);and wherein the transceiver (112) is configured to wirelessly transmit the data signal (110) external to the detection circuit (100).
2. The detection circuit according to claim 1 ; wherein data signal (110) is a binary signal deterministic of:i) either a signal present in the at least one fiber optic cable (114, 116) ii) or no signal present in the at least one fiber optic cable (114, 116).
3. The detection circuit according to any preceding claim; wherein the diverted percentage of light is at least 5% of the light signal carried in the at least one fiber optic cable (114, 116).
4. The detection circuit (200) according to any preceding claim; wherein the transceiver is an NFC-tag (212), and wherein the NFC-tag is configured to be inductively powered by an electromagnetic signal (222) external to the detection circuit.
5. The detection circuit (300) according to claim 4; wherein the detection circuit further comprises at least one light-emitting diode (330) in electronic communication with the processor (308) and the NFC-tag (312);wherein the at least one light-emitting diode is further configured to receive electrical power from the NFC-tag when the NFC is inductively powered by an electromagnetic signal (322) external to the detection circuit.
6. The detection circuit according to claims 2 to 5; wherein the binary signal is a voltage signal.
7. The detection circuit according to claim 6; wherein the voltage signal deterministic of a signal present in the at least one fiber optic cable is a first voltage signal of 2.55V.
8. The detection circuit according to claims 5 to 7; wherein the voltage signal deterministic of no signal present in the at least one fiber optic cable is a second voltage signal of 1.3V.
9. The detection circuit according to claims 5 to 8; wherein the least one light-emitting diode (330) in electronic communication with the processor configured to be electrically powered by the first voltage signal only.
10. A user device (220, 320, 420) for use with the detection circuit of claims 1 to 9; wherein the user device comprises: a receiver and a display (224, 424);wherein the receiver is in electronic communication with the display and is configured to wirelessly receive the data signal from the detection circuit, at the receiver, and display the data signal on the display.
11. The user device of claim 10; wherein the receiver of the user device is an NFC- reader configured to generate the electromagnetic signal to inductively power the NFC-tag in the light detection circuit.
12. The user device of claims 10 to 11; wherein the display (224, 424) comprises a graphical user interface.
13. The user device of claim 12; wherein the graphical user interface is generated by at least one application installed on a memory of the user device.
14. A method (1000) for detecting a data signal in at least one fiber optic cable,the method implemented by the detection circuit (100, 200, 300, 400, 500) of claims 1 to 9 and comprising the following steps:- the at least one splitter diverting the percentage of light from the signal to the at least one photodiode (1002);- the at least one photodiode converting the percentage of light into the voltage, and transferring the voltage to the processor(1004), the processor determining, from the voltage, the data signal associated with the at least one fiber optic cable (1006),- the processor transferring the data signal to the transceiver (1008), and - the transceiver wirelessly transmitting the data signal external to the detection circuit (1010).
15. The method of claim 14; wherein the data signal is a binary signal deterministic of either i) a signal present in the at least one fiber optic cable or ii) no signal present in the at least one fiber optic cable.
16. The method of claim 15; wherein the binary signal is indicated, external to the detection circuit, by an illumination of the at least one light-emitting diode (330).
17. The method of claim 16; wherein the binary signal is wirelessly received from the light detection circuit of claims 1 to 9, at the receiver of the user device (220, 320, 420) of claims 10 to 13, and wherein the binary signal is displayed on the display (224, 424) of the user device.