Multi-channel wavelength division multiplexing optical communication module integrated with OTDR function

Abstract

The utility model discloses a multichannel wavelength division multiplexing optical communication module integrated with an OTDR function. Comprising a communication signal emission driving array, an OTDR signal emission driving array, a first laser array, a second laser array, a wavelength division multiplexing optical path array, a communication receiving optical path array, a communication signal detector, a communication signal amplifier, an OTDR detector, an OTDR processing circuit and a microcontroller. Wherein the OTDR signal emission driving array can output a narrow pulse electric signal to drive the second laser array to emit a nanosecond-level or hundred picosecond-level OTDR optical pulse, and the OTDR detection requirement of a multimode optical fiber network in which the optical fiber distance is within 300 meters and the distance between two event points is dozens of centimeters or less is met. The wavelength division multiplexing technology is adopted to achieve both the high-speed communication function and the optical fiber network diagnosis function, the size is small, power consumption is low, and the device can be applied to the application fields of data center communication networks and special optical networks.

Description

Technical Field

[0001] The utility model belongs to the technical field of optical fiber communication, and in particular relates to an optical communication module which can be applied to a multi-mode optical fiber network. Background Art

[0002] Fiber-optic communication is a communication method that uses light waves as information carriers and optical fibers as transmission media. It has become one of the main pillars of modern communications.

[0003] With the continuous development and large-scale application of fiber-optic communication technology, the complexity of fiber-optic networks is increasing. In actual use, when the quality of fiber-optic link connection needs to be maintained and diagnosed, technicians are required to disconnect the fiber-optic network on site, and then use the optical time domain reflectometer (OTDR) to locate and diagnose the fiber-optic link breakpoint event, and then troubleshoot and repair the fiber-optic network, which is time-consuming, labor-intensive and has high maintenance costs.

[0004] In order to solve the above problems, optical modules with integrated OTDR functions have appeared in the field of access network communications. Compared with OTDR test instruments, this type of optical module is relatively small in size and does not need to disconnect the optical fiber network during testing. However, it can only be used in single-mode optical fiber links with a single optical fiber channel and a long optical fiber distance. At the same time, due to the difficulty of integration, the packaging of optical modules with OTDR functions can only be realized in SFP or SFP+ packaging forms.

[0005] In the field of data center communications and special optical network applications, compared with the field of access network communications, there are more optical fibers in the optical cable, which can transmit multiple communication optical signals at the same time, and the optical fibers are mostly multi-mode optical fibers, and the optical modules used are multi-channel optical communication modules. This type of multi-channel optical communication module has a small package volume, high transmission rate requirements for communication signals, and short fiber distances in the multi-mode optical fiber links, many fiber connection points, and short fiber lengths between nodes. Therefore, it is impossible to directly transplant the OTDR integration technology of optical modules in the field of access network communications to multi-channel optical communication modules. Therefore, there are currently no multi-channel optical communication modules with integrated OTDR functions in the industry. Utility Model Content

[0006] The utility model aims to provide a multi-channel wavelength division multiplexing optical communication module integrated with an OTDR function, so as to solve the problem that the multi-channel optical communication module used in the existing multi-mode optical fiber network does not have the OTDR function.

[0007] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0008] A multi-channel wavelength division multiplexing optical communication module integrated with an OTDR function, comprising:

[0009] A communication signal transmission drive array, which is used to modulate n-channel high-speed communication transmission signals, load them onto the first laser array, and drive the first laser array to emit n-channel communication optical signals with a wavelength of λ1, where n is an integer greater than 1;

[0010] An OTDR signal emission drive array, which is used to output n narrow pulse electrical signals to drive the second laser array to emit n OTDR optical pulses with a wavelength of λ2, where λ2≠λ1;

[0011] A wavelength division multiplexing optical path array, which is used to inject n communication optical signals and n OTDR optical pulses into n transmitting optical fibers respectively, and receive back-reflected and scattered optical signals generated when the OTDR optical pulses propagate in the transmitting optical fibers;

[0012] A communication signal detector, which is used to perform photoelectric conversion on the received n-way transmission communication optical signals;

[0013] A communication signal amplifier, which is used to amplify and shape the n-channel electrical signals output by the communication signal detector and output an n-channel high-speed communication receiving signal;

[0014] An OTDR detector, which is used to perform photoelectric conversion on n-path back-reflected and scattered light signals output by the wavelength division multiplexing optical path array;

[0015] An OTDR processing circuit, which is used to amplify, shape, filter, and perform analog-to-digital conversion on n-channel electrical signals output by the OTDR detector, and then output backward signal strength data that varies with time;

[0016] A microcontroller generates data showing a variation of the backward signal strength with the optical fiber distance according to the backward signal strength data showing a variation with time, so as to generate an OTDR test curve and / or an event table.

[0017] In some embodiments of the present application, for a multimode optical fiber network, the transmitting optical fiber can be configured as a multimode optical fiber; the microcontroller can control the first laser array to output a communication optical signal with a wavelength that is the same as or close to the communication band of the multimode optical fiber. In addition, the microcontroller can also control the second laser array to output a laser signal with a wavelength of λ2 according to the wavelength λ2 of the required OTDR optical pulse for OTDR detection. In addition, the microcontroller can also control the OTDR signal emission drive array to output a narrow pulse electrical signal of nanoseconds or hundreds of picoseconds to drive the second laser array to output an OTDR optical pulse with a pulse width of nanoseconds or hundreds of picoseconds to meet the OTDR detection requirements of multimode optical fiber links with a transmission distance of less than 300 meters.

[0018] In some embodiments of the present application, in order to reliably receive counter-communication optical signals, a communication receiving optical path array can be set in a multi-channel optical module and coupled with n receiving optical fibers. The communication receiving optical path array is used to focus the n counter-communication optical signals transmitted through the n receiving optical fibers and then inject them into the communication signal detector, thereby increasing the optical power of the received optical signal.

[0019] In some embodiments of the present application, in order to obtain a narrow pulse electrical signal of nanosecond level or hundred-picosecond level, n narrow pulse electrical signal generating circuits may be provided in the OTDR signal emission drive array, and a NOT gate, an AND gate and an adjustable resistor may be provided in each narrow pulse electrical signal generating circuit, wherein the NOT gate is used to invert a pulse signal output by a microcontroller; the AND gate is used to perform an AND operation on the pulse signal output by the NOT gate and another pulse signal output by the microcontroller to generate an output pulse; the adjustable resistor is connected between the output end of the AND gate and the second laser array, and the optical power of the OTDR optical pulse emitted by the second laser array is adjusted by changing the driving current applied to the second laser array.

[0020] The microcontroller can be configured to change the pulse width of the output pulse generated by the AND gate by adjusting the time difference between the two pulse signals outputted by the microcontroller, thereby obtaining a nanosecond or 100-picosecond narrow pulse electrical signal. The narrow pulse electrical signal is used to drive the laser in the second laser array to emit light, thereby generating a nanosecond or 100-picosecond narrow pulse optical signal to meet the OTDR detection requirements of multimode optical fiber links with a distance between event points of tens of centimeters or less.

[0021] In some embodiments of the present application, the laser may be a VCSEL laser operating at a low current to meet the driving requirements of the AND gate output pulse for the laser. n VCSEL lasers may be arranged in the second laser array, and each VCSEL laser may be driven by one of the narrow pulse electrical signal generating circuits, thereby generating n OTDR optical pulses for OTDR detection of n transmitting optical fibers in a multimode optical fiber link.

[0022] In some embodiments of the present application, in order to meet the miniaturization design of the optical communication module, the following may be set in the wavelength division multiplexing optical path array:

[0023] A lens base body, on which a first groove and a second groove are formed, and an inclined surface is formed, wherein the inclined surface forms a total reflection surface;

[0024] A first beam splitter, which is installed in the first groove and has two parallel and opposite first and second surfaces, wherein the first surface reflects light with a wavelength of λ1 and transmits light with a wavelength of λ2, and the second surface transmits light with a wavelength of λ2;

[0025] A second beam splitter, which is installed in the second groove and has two parallel and opposite first and second surfaces, wherein the first surface semi-reflects and semi-transmits light with a wavelength of λ2, and the second surface transmits light with a wavelength of λ2;

[0026] Four lens arrays, among which,

[0027] The first lens array performs collimation processing on the communication optical signal with a wavelength of λ1 emitted by the first laser array, generates a parallel light beam, which is transmitted in the lens matrix, enters the first groove and is emitted to the first surface of the first beam splitter, is reflected by the first surface of the first beam splitter, and is emitted in parallel to the fourth lens array. After being focused by the fourth lens array, it enters the transmitting optical fiber;

[0028] The second lens array performs collimation processing on the OTDR light pulses with a wavelength of λ2 emitted by the second laser array, generates a parallel light beam which is transmitted in the lens matrix, enters the second groove and is emitted to the first surface of the second beam splitter, is reflected by the first surface of the second beam splitter, is emitted in parallel to the second surface of the first beam splitter, is transmitted through the first beam splitter, is emitted in parallel to the fourth lens array, is focused by the fourth lens array, and enters the transmitting optical fiber;

[0029] The fourth lens array performs collimation processing on the back-reflected and scattered light signals returned through the transmitting optical fiber, generates a parallel light beam that enters the lens base, and then transmits through the first beam splitter and the second beam splitter, and then is directed parallel to the inclined surface of the lens base, and after being reflected by the inclined surface, it is directed parallel to the third lens array, and after being focused by the third lens array, it is directed to the OTDR detector for photoelectric conversion.

[0030] In this way, a lens substrate and two beam splitters can be used to couple the communication optical signal and the OTDR optical pulse, and to collect the back-reflected and scattered optical signals. It is small in size and can be directly mounted on the PCB board of the optical communication module, thereby significantly reducing the package size of the optical communication module.

[0031] In some embodiments of the present application, in order to reduce the height of the lens base, the first groove and the second groove can be arranged in parallel, and the second groove is located between the first groove and the inclined surface to meet the coupling or separation requirements of communication optical signals, OTDR optical pulses, backreflected and scattered optical signals.

[0032] In some embodiments of the present application, the first beam splitter can be installed in the first groove at an angle of 45° to form an angle of 45° with the bottom surface of the first groove; the second beam splitter can be installed in the second groove at an angle of 45° to form an angle of 45° with the bottom surface of the second groove. By changing the propagation direction of the optical signal, the volume of the lens matrix can be further limited.

[0033] In some embodiments of the present application, the four groups of lens arrays can be respectively arranged on two adjacent outer surfaces of the lens substrate, one of the outer surfaces is adjacent to the bottom surfaces of the first groove and the second groove, and the first group of lens arrays, the second group of lens arrays and the third group of lens arrays are arranged thereon, and the arrangement positions of the three groups of lens arrays correspond one by one to the positions of the first groove, the second groove and the inclined surface respectively; the other outer surface of the lens substrate is adjacent to the first surface of the first beam splitter, and the fourth group of lens arrays is arranged thereon.

[0034] In some embodiments of the present application, n lenses that are spaced apart and do not interfere with each other can be configured in the four groups of lens arrays to avoid interference between n communication optical signals, n OTDR optical pulses, and n back-reflected and scattered optical signals when they propagate in the lens matrix.

[0035] Compared with the prior art, the advantages and positive effects of the utility model are mainly reflected in:

[0036] 1. The optical communication module of the utility model adopts wavelength division multiplexing technology for multi-channel multi-mode optical fiber communication network. While ensuring the multi-channel high-speed communication rate, it has an embedded optical fiber network diagnostic function. During the test, there is no need to disconnect the optical fiber network, and the real-time monitoring of the optical fiber network connection status can be achieved, thereby improving the maintenance efficiency of the multi-channel multi-mode optical fiber communication network.

[0037] 2. The utility model sets an OTDR signal emission drive array that can generate narrow pulse electrical signals in the optical communication module to drive the second laser array to emit nanosecond or hundred-picosecond OTDR optical pulses, thereby meeting the OTDR detection needs of multi-mode optical fiber networks with an optical fiber distance of less than 300 meters and a distance between two event points of tens of centimeters or less.

[0038] 3. The optical communication module of the utility model is particularly suitable for use in optical fiber links in the field of data center communications and special optical network applications to solve the problems of daily management, maintenance and detection of optical fiber networks in this field.

[0039] After reading the detailed description of the embodiments of the present invention in conjunction with the accompanying drawings, other features and advantages of the present invention will become more clear. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0041] Figure 1 It is a circuit schematic diagram of an embodiment of a narrow pulse optical signal generating circuit;

[0042] Figure 2 yes Figure 1 The waveform diagram of the input pulse and output pulse of the AND gate;

[0043] Figure 3 This is an overall architecture diagram of an embodiment of a multi-channel wavelength division multiplexing optical communication module with an integrated OTDR function proposed by the utility model;

[0044] Figure 4 yes Figure 3 A schematic structural diagram of an embodiment of a wavelength division multiplexing optical path array;

[0045] Figure 5 yes Figure 4 A top view of the wavelength division multiplexing optical path array shown;

[0046] Figure 6 yes Figure 3 A structural schematic diagram of an embodiment of a communication receiving optical path array in FIG. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0048] In the description of the present invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore, cannot be understood as a limitation on the present invention. The terms "front" and "rear" are defined according to the transmission direction of electrical or optical signals.

[0049] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to the specific circumstances. In the description of the implementation method, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0050] The terms "first", "second", "third", "fourth", "fifth", and "sixth" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", "third", "fourth", "fifth", and "sixth" may explicitly or implicitly include one or more of the features.

[0051] In the description of the present invention, unless otherwise specified, “plurality” means two or more.

[0052] The OTDR optical modules (optical modules with integrated OTDR functions) in the industry are mainly designed for long-distance single-mode fiber networks. The length of the fiber link ranges from several kilometers to tens of kilometers. The width of the optical pulses emitted by this OTDR optical module for OTDR detection is generally tens of nanoseconds or more, corresponding to a fiber distance resolution of several meters.

[0053] For multimode fiber networks, the length of the fiber link is generally in the range of several meters to three hundred meters, and the distance between two event points (such as two connectors) is tens of centimeters or less. Therefore, optical pulses of tens of nanoseconds cannot meet the OTDR detection requirements of multimode fiber links.

[0054] Therefore, in order to be applicable to short-distance multimode optical fiber transmission links, it is necessary to configure a nanosecond or even hundreds of picosecond narrow pulse optical signal generation circuit in the OTDR optical module.

[0055] like Figure 1As shown, the narrow pulse optical signal generating circuit of this embodiment is mainly composed of a narrow pulse electrical signal generating circuit and a laser Laser, wherein the narrow pulse electrical signal generating circuit is mainly composed of a microcontroller, a digital gate device, an adjustable resistor R and other components. Among them, the microcontroller outputs two pulse signals IN1 and IN2, and there is a certain delay between the two pulse signals IN1 and IN2, and the delay size can be achieved by the microcontroller by controlling the output time difference of the two pulse signals IN1 and IN2. One of the pulse signals IN1 is transmitted to one input end of the AND gate AND, and the other pulse signal IN2 is inverted through the NOT gate NOT to obtain an inverted pulse signal -IN2 and transmit it to the other input end of the AND gate AND. After the AND gate AND performs an AND operation on the two received pulse signals IN1 and -IN2, an output pulse OUT is generated, which is transmitted to the anode of the laser Laser through the adjustable resistor R1, and the cathode of the laser Laser can be grounded, thereby controlling the light emission of the laser Laser.

[0056] Since there is a time delay between the two inverted pulse signals IN1 and -IN2 entering the AND gate, Figure 2 As shown, therefore, the pulse width of the output pulse OUT generated after the AND gate AND is equal to or slightly less than the delay time between the two inverted pulse signals IN1 and IN2. Therefore, by adjusting the time difference between the two pulse signals IN1 and IN2 output by the microcontroller, a narrow pulse electrical signal of nanoseconds or hundreds of picoseconds can be obtained. By using the narrow pulse electrical signal to drive the laser to emit light, a narrow pulse optical signal of nanoseconds or hundreds of picoseconds can be generated for OTDR detection.

[0057] This embodiment generates nanosecond or picosecond optical pulses by controlling the delay between two pulse signals. The solution is simple and only a small number of gate devices are needed. The gate devices are small in size, so they are easy to integrate and are conducive to the miniaturization of optical module packaging. At the same time, by adjusting the delay between the two pulse signals output by the microcontroller, the pulse width of the generated optical pulse can be adjusted, thereby providing technical support for subsequent intelligent pulse width adjustment.

[0058] In addition, by changing the resistance value of the adjustable resistor R, the optical power of the narrow pulse optical signal emitted by the VCSEL laser can be adjusted.

[0059] Different from the single-channel edge-emitting DFB / FP laser driven by high current in the access network OTDR optical module, this embodiment is aimed at a multi-channel optical module suitable for a multimode optical fiber network. Figure 1In addition to the multi-channel expansion of the narrow pulse optical signal generating circuit shown in the figure to form an array form, the laser Laser is preferably a surface-emitting, small-current driven VCSEL laser. On the one hand, it can meet the driving of the VCSEL laser by the narrow pulse electrical signal output by the AND gate AND, and on the other hand, it can facilitate the formation of a VCSEL laser array to adapt to the small-size packaging structure of the multi-channel optical module. By reducing the working current of the laser, the power consumption of the optical module can be significantly reduced.

[0060] Based on the above narrow pulse optical signal generating circuit and its array form, this embodiment designs the following Figure 3 The multi-channel optical communication module shown has a multi-channel parallel high-speed communication function and a multi-channel parallel optical fiber network intelligent detection function. The two functions use wavelength division multiplexing to achieve function multiplexing and isolation without affecting each other. Without interrupting the high-speed communication service, real-time monitoring of the multi-mode optical fiber network connection status can be performed.

[0061] like Figure 3 As shown, the multi-channel optical communication module of this embodiment mainly includes a communication signal transmission drive array, an OTDR signal transmission drive array, a first laser array (hereinafter referred to as laser array 1), a second laser array (hereinafter referred to as laser array 2), a wavelength division multiplexing optical path array, a communication receiving optical path array, a communication signal detector 5, a communication signal amplifier, an OTDR detector 3, an OTDR processing circuit, a microcontroller and other components.

[0062] The communication signal transmission drive array can be directly designed using the laser drive circuit in the existing multi-channel optical communication module without OTDR function (i.e., using the existing technology) to modulate the multi-channel high-speed communication transmission signal and load it onto the laser array 1. The wavelength λ1 of the communication optical signal emitted by the laser array 1 is controlled according to the multi-mode optical fiber communication band, so that λ1 is the same as or close to the multi-mode optical fiber communication band, for example, a laser signal with a wavelength of 850nm is output to meet the communication requirements of the multi-mode optical fiber network.

[0063] In this embodiment, the laser array 1 may be an array composed of n VCSEL lasers, wherein n is equal to the number of channels of the multi-channel optical communication module.

[0064] The OTDR signal transmission drive array can be used as follows Figure 1The gate device circuit shown is constructed in the form of an array according to the number of channels n. The time difference between the two pulse signals IN1 and IN2 output by the microcontroller is adjusted to control the pulse width of the narrow pulse electrical signal output by the OTDR signal emission driving array. For example, the pulse width of the narrow pulse electrical signal is adjusted to the nanosecond level or the hundred-picosecond level to drive the laser array 2 behind it to output a nanosecond or hundred-picosecond level narrow pulse optical signal, i.e., an OTDR optical pulse, for OTDR detection of multimode optical fiber links.

[0065] In this embodiment, the wavelength λ2 of the OTDR optical pulse output by the laser array 2 can be controlled by the microcontroller. The wavelength λ2 can be near the wavelength λ1 of the communication optical signal, but should be significantly different from the wavelength λ1. For example, λ2 can be 830nm, 870nm or 910nm, etc., to avoid mutual interference between the two groups of laser signals and realize wavelength division multiplexing.

[0066] After the n-channel communication optical signals emitted by the laser array 1 and the n-channel OTDR optical pulses emitted by the laser array 2 are coupled via the wavelength division multiplexing optical path array, they enter the same optical cable. In this embodiment, the optical cable is a section of an optical cable in a multi-channel multimode optical fiber link 4, which integrates n transmitting optical fibers and n receiving optical fibers, each of which is a multimode optical fiber. In this embodiment, in addition to transmitting one communication optical signal, one OTDR optical pulse is also transmitted in each transmitting optical fiber.

[0067] The n-way counter-communication optical signals from the opposite optical module are transmitted to the multi-channel optical communication module of this embodiment through the n receiving optical fibers in the optical cable. The wavelength of the n-way counter-communication optical signals is also λ1, and after being focused by the communication receiving optical path array, they are transmitted to the communication signal detector 5 to complete the conversion of the optical signal to the electrical signal. The n-way electrical signals output by the communication signal detector 5 are amplified, shaped, etc. by the communication signal amplifier, and can be output to the user side through the electrical interface receiving end on the multi-channel optical communication module.

[0068] In this embodiment, the communication signal detector 5 and the communication signal amplifier each have n channels, each channel receives a communication optical signal, completes the photoelectric conversion and the amplification and shaping of the electrical signal, and then outputs a high-speed communication reception signal.

[0069] When the OTDR light pulse with a wavelength of λ2 propagates in the optical fiber link, a reflection signal will be generated when it encounters the optical fiber connection, break, defect, end face and tail end. At the same time, Rayleigh scattering will be caused by the uneven particles in the optical fiber material. The back reflection and scattered signals are received by the wavelength division multiplexing optical path array and enter the OTDR detector 3 in reverse to convert the back light signal into an electrical signal. After being sent to the OTDR processing circuit for amplification, shaping, filtering, high-speed analog-to-digital conversion and other processing, the back signal strength data that varies with time can be obtained and sent to the microcontroller. The microcontroller can further process the data to obtain the data on the back signal strength that varies with the optical fiber distance, and the data interface (such as I 2 C interface or SPI interface, etc.) to generate OTDR test curves and / or event tables.

[0070] In this embodiment, the OTDR detector 3 and the OTDR processing circuit each include n channels, and each channel completes processing tasks such as photoelectric conversion, amplification, shaping, filtering, and high-speed analog-to-digital conversion of a backward optical signal.

[0071] The specific working principle of the multi-channel wavelength division multiplexing optical communication module of this embodiment mainly includes:

[0072] When the optical network connection is normal, the multi-channel optical communication module performs the high-speed communication function, receives the multi-channel high-speed communication transmission signals output by the user side through its electrical interface transmitting end, and the microcontroller controls the communication signal transmission driving array to complete the modulation of the multi-channel high-speed communication transmission signals, loads them onto the laser array 1, and drives the laser array 1 to emit a communication optical signal with a wavelength of λ1, thereby realizing the conversion of electrical signals to optical signals.

[0073] The communication optical signal loaded with communication data is converged by the wavelength division multiplexing optical path array, and then emitted into the multi-channel multimode optical fiber link 4 through the optical interface of the optical communication module, and is received by the optical module on the opposite side, completing the communication signal transmission function.

[0074] At the same time, the optical communication module receives the counter-communication optical signal emitted by the opposite optical module through the multi-channel multimode optical fiber link 4, transmits it to the communication signal detector 5 through the communication receiving optical path array, converts the optical signal into an electrical signal, and then amplifies and shapes the electrical signal through the communication signal amplifier to generate a high-speed communication receiving signal, which is output to the user side through the electrical interface receiving end of the optical communication module.

[0075] When the optical fiber network needs to be monitored, or a fault occurs in the optical fiber network, or the microcontroller finds that the communication link is not communicating normally (for example, the received optical power is reduced to a certain set threshold value, etc.), the microcontroller automatically starts the optical fiber network connection monitoring function, controls the OTDR signal emission drive array to generate the narrow pulse electrical signal required for OTDR detection, drives the laser array 2 to emit an OTDR optical pulse with a wavelength of λ2, and after being focused by the wavelength division multiplexing optical path array, it is emitted into the multi-channel multimode optical fiber link 4 through the optical interface of the optical communication module to realize the emission of the OTDR optical pulse.

[0076] During the transmission of OTDR optical pulses in a multi-channel multimode optical fiber link, a reflection signal is generated when encountering optical fiber connections, breaks, defects, end faces, and tail ends, and a scattering signal is generated when encountering uneven particles in the optical fiber material causing Rayleigh scattering. The back-reflected signal and the back-scattered signal enter the OTDR detector 3 via the wavelength division multiplexing optical path array, and the back-reflected optical signal is converted into an electrical signal. After amplification, shaping, filtering, high-speed analog-to-digital conversion, etc., the OTDR processing circuit obtains the back-reflected signal intensity data that varies with time and sends it to the microcontroller.

[0077] The microcontroller further processes the received backward signal strength data varying with time to obtain data on the variation of the backward signal strength with the optical fiber distance, so as to generate an OTDR test curve and / or an event table, which is reported through the data interface of the optical communication module.

[0078] Due to the use of wavelength division multiplexing, the communication service function and the optical fiber connection monitoring function are independent of each other and do not interfere with each other. There is no need to interrupt the transmission of high-speed communication signals when monitoring the optical fiber network connection. Therefore, the application scenarios of optical communication modules can be expanded, including but not limited to:

[0079] (1) After the fiber optic network wiring is completed, the optical communication module can be used to scan the connection status of the fiber optic network to obtain a topological diagram of the fiber optic network connection status;

[0080] (2) During the communication business process, the optical communication module can be used to scan and monitor the connection status of the optical fiber network in real time;

[0081] (3) When the optical communication module finds that the communication service is abnormal, it can automatically scan, detect, judge and process the optical fiber network in more depth to obtain the fault information of the optical fiber network and assist users in repair.

[0082] The multi-channel optical communication module needs to adopt a multi-channel lens array to realize the multi-channel high-speed communication function. Moreover, the multi-channel optical communication module of this embodiment also needs to integrate the OTDR detection function on this basis. Therefore, the wavelength division multiplexing optical path array needs to be specially designed.

[0083] Combination Figure 4 , Figure 5 As shown, the wavelength division multiplexing optical path array of this embodiment includes a lens substrate 10, on which two parallel first grooves 11 and second grooves 12 are formed, and an inclined surface 13 is formed, and the second groove 12 is configured to be located between the first groove 11 and the inclined surface 13, and the inclined surface 13 can form a total reflection surface.

[0084] A first beam splitter 20 is installed in the first groove 11. The first beam splitter 20 is tilted in the first groove 11, for example, it can form a 45° angle with the bottom surface of the first groove 11. The first beam splitter 20 includes two parallel and opposite surfaces 21 and 22, wherein the first surface 21 reflects the light of wavelength λ1 and transmits the light of wavelength λ2; the second surface 22 transmits the light of wavelength λ2.

[0085] A second beam splitter 30 is installed in the second groove 12. The second beam splitter 30 is tilted in the second groove 12, for example, it can form a 45° angle with the bottom surface of the second groove 12. The second beam splitter 30 includes two parallel and opposite surfaces 31 and 32. The first surface 31 semi-reflects and semi-transmits light with a wavelength of λ2; the second surface 32 transmits light with a wavelength of λ2.

[0086] Lens arrays are arranged on two adjacent outer side surfaces 14 and 15 of the lens base 10, respectively. One of the outer side surfaces 14 is adjacent to the bottom surfaces of the grooves 11 and 12, and three groups of lens arrays 41, 42, and 43 are arranged thereon. The positions of the three groups of lens arrays 41, 42, and 43 correspond to the positions of the first groove 11, the second groove 12, and the inclined surface 13. The other outer side surface 15 of the lens base 10 is adjacent to the first surface 21 of the first beam splitter 20, and a fourth group of lens arrays 44 is arranged thereon.

[0087] In some embodiments, the number of lenses in each lens array 41 - 44 can be respectively matched with the number of channels n of the optical communication module, and the n lenses in each lens array 41 - 44 are spaced apart from each other and do not interfere with each other. Figure 5 It shows a situation where four lenses are respectively configured in each lens array group 41-44, which can be applied to an optical communication module with less than four channels.

[0088] In this embodiment, the first lens array 41 corresponding to the position of the first groove 11 can face the laser array 1, and after the communication optical signal with a wavelength of λ1 emitted by the laser array 1 is collimated, a parallel light beam 17 is generated and propagates in the lens base 10, and then enters the first groove 11, and is emitted to the first surface 21 of the first beam splitter 20. After being reflected by the first surface 21 of the first beam splitter 20, it is emitted in parallel to the fourth lens array 44, and after being focused by the fourth lens array 44, it enters the multi-channel multimode optical fiber link 4, thereby realizing the transmission of high-speed communication optical signals.

[0089] The second lens array 42 corresponding to the position of the second groove 12 can face the laser array 2, and after the OTDR light pulse with a wavelength of λ2 emitted by the laser array 2 is collimated, a parallel light beam 18 is generated to propagate in the lens substrate 10, and then enters the second groove 12, and is emitted to the first surface 31 of the second beam splitter 30. After being reflected by the first surface 31 of the second beam splitter 30, it is emitted in parallel to the second surface 21 of the first beam splitter 20, and after being transmitted through the first beam splitter 20, it is emitted in parallel to the fourth lens array 44. After being focused by the fourth lens array 44, it enters the multi-channel multimode optical fiber link 4 to realize the emission of OTDR light pulses.

[0090] The OTDR light pulse transmitted in the multi-channel multi-mode optical fiber link 4 generates a back reflection signal when encountering the optical fiber connection, break, defect, end face and tail end, and the back Rayleigh scattering signal generated when encountering the uneven particles in the optical fiber material. The back reflection signal is returned by the multi-channel multi-mode optical fiber link 4, and after being collimated by the fourth lens array 44, a parallel light beam 19 is generated to enter the lens base 10, and then after being transmitted through the first beam splitter 20, it is parallel to the second beam splitter 30, after being transmitted through the second beam splitter 30, it is parallel to the inclined surface 13 of the lens base 10, after being reflected by the inclined surface 13, it is parallel to the third lens array 43, after being focused by the third lens array 43, it is emitted to the OTDR detector 3 for photoelectric conversion, so as to realize the reception and detection of the back reflection and scattered signals.

[0091] The outer side surface 14 of the lens substrate 10 can be used as the bottom surface of the lens substrate 10, and a support foot is formed thereon. The lens substrate 10 is directly mounted on the PCB board inside the optical communication module through the support foot. The laser array 1, the laser array 2, and the OTDR detector 3 are mounted on the PCB board and are located below the lens substrate 10. While meeting the communication optical signal and OTDR optical pulse emission and the back reflection and scattered signal reception, the occupied space can be reduced, the packaging size of the optical communication module can be reduced, and a miniaturized design can be achieved.

[0092] For the n-way counter-communication optical signals transmitted to the optical communication module through the receiving optical fiber, two groups of lens arrays can be extended on the wavelength division multiplexing optical path array to take into account the reception. For example, the fifth group of lens arrays is arranged on the outer side surface 15 of the lens substrate 10, and the sixth group of lens arrays is arranged on the outer side surface 14 of the lens substrate 10 at a position corresponding to the bottom surface of the first groove 11. After the counter-communication optical signal with a wavelength of λ1 transmitted through the receiving optical fiber is collimated by the fifth group of lens arrays, a parallel light beam is formed, which is emitted to the first surface 21 of the first beam splitter 20, and after being reflected by the first surface 21 of the first beam splitter 20, it is emitted to the sixth group of lens arrays, and after being focused by the sixth group of lens arrays, it is emitted to the communication signal detector 5 to realize the reception and photoelectric conversion of the counter-communication optical signal.

[0093] When the counter-transmitted OTDR optical pulse with a wavelength of λ2 emitted from the opposite side enters the optical communication module on the user side through the receiving optical fiber, it is first collimated by the fifth lens array to form a parallel light beam, which is then emitted to the first surface 21 of the first beam splitter 20. Since the first surface 21 of the first beam splitter 20 fully transmits the light with a wavelength of λ2, the counter-transmitted OTDR optical pulse emitted from the opposite side will not be emitted to the communication signal detector 5, and therefore will not affect the counter-transmitted communication optical signal, thereby achieving the isolation of OTDR diagnosis and communication signals.

[0094] Of course, a communication receiving optical path array may also be separately configured in the multi-channel optical communication module, which is dedicated to receiving the transmitted communication optical signal.

[0095] like Figure 6 As shown, the communication receiving optical path array of this embodiment may include a lens substrate 50, on which a groove 51 is provided, and a third beam splitter 60 is obliquely installed in the groove 51. The third beam splitter 60 is obliquely arranged in the groove 51, for example, it may form a 45° angle with the bottom surface of the groove 51, so as to change the transmission direction of the light. The third beam splitter 60 includes two parallel and opposite surfaces 61 and 62, wherein the first surface 61 reflects the light of wavelength λ1 and transmits the light of wavelength λ2; the second surface 62 transmits the light of wavelength λ2. On the lens substrate 50, an inclined surface 54 is formed on the outer surface adjacent to the second surface 62 of the third beam splitter 60, and the inclined surface 54 is a total reflection surface.

[0096] The sixth lens array 46 is mounted on the bottom surface 52 of the lens base 50 (the outer side surface adjacent to the bottom surface of the groove 51), and its mounting position is vertically opposite to the mounting position of the third beam splitter 60 in the groove 51. The fifth lens array 45 is mounted on the outer side surface 53 of the lens base 50 adjacent to the first surface 51 of the third beam splitter 50.

[0097] In the fifth lens array 45 and the sixth lens array 46, n lenses that are spaced apart from each other and do not interfere with each other are respectively arranged.

[0098] The n-way counter-propagation communication optical signal + OTDR optical pulse transmitted through the multi-channel multimode optical fiber link 4 is first incident on the fifth lens array 45 for collimation, and after forming a parallel beam, it is incident on the third beam splitter 60. The first surface 61 of the third beam splitter 60 reflects the counter-propagation communication light with a wavelength of λ1, changes its propagation path, and is incident on the sixth lens array 46. After being focused by the sixth lens array 46, it is incident on the communication signal detector 5, and the communication signal detector 5 converts the counter-propagation communication optical signal into an electrical signal, which is output to the communication signal receiving amplifier. The counter-propagation OTDR optical pulse with a wavelength of λ2 is incident on the inclined surface 54 of the lens base 50 after transmitting through the third beam splitter 60, and is reflected downward by the inclined surface 54, and is incident through the bottom surface 52 of the lens base 50. A lens array 47 can be further arranged on the bottom surface 52 of the lens base 50, and the arrangement position of the lens array 47 is configured to be opposite to the position of the inclined surface 54. After the lens array 47 reflects and outputs the counter-transmitted OTDR light pulses from the inclined surface 54 and converges them at one point, the communication receiving optical path array is emitted.

[0099] A foot can be formed on the bottom surface of the lens base 50, and the lens base 50 can be directly mounted on the PCB board of the optical communication module through the foot, and the communication signal detector 5 and the communication signal receiving amplifier can be mounted on the PCB board. The communication signal detector 5 and the communication signal receiving amplifier can be arranged below the lens base 50 to reduce space occupation and realize a small-size package of the optical communication module. At the same time, the counter-transmitted OTDR optical pulses emitted by the lens array 47 can be converged on the PCB board to prevent them from being diverged inside the optical communication module and generating crosstalk with other optical signals.

[0100] In this embodiment, the wavelength division multiplexing optical path array and the communication receiving optical path array are directly installed on the PCB board, which is very close to the laser array 1, the laser array 2, the communication signal detector 5, and the OTDR detector 3, thereby ensuring the continuity of high-speed optical signal transmission and meeting the high-speed communication requirements of the multi-mode optical fiber network.

[0101] This embodiment is designed for the data center communication network field and special optical network application field with a large number of optical fiber channels and complex connections, and an optical communication module with integrated multi-channel parallel high-speed communication function and multi-channel optical fiber network detection function is designed. It can be widely used in Internet, vehicle-mounted, airborne, ground and other optical fiber communications or Internet of Everything optical fiber networks. Without disconnecting the optical fiber network, it can replace manual completion of automatic detection of the connection status of the multi-channel multi-mode optical fiber network, and is particularly suitable for monitoring the network connection status in scenarios with complex connections or difficult to disassemble and assemble.

[0102] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, it is still possible for a person skilled in the art to modify the technical solutions described in the above embodiments, or to replace some of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions claimed to be protected by the present invention.

Claims

1. A multi-channel wavelength division multiplexing optical communication module integrated with OTDR function, comprising: A communication signal transmission drive array, which is used to modulate n-channel high-speed communication transmission signals, load them onto the first laser array, and drive the first laser array to emit n-channel communication optical signals with a wavelength of λ1, where n>1; A communication signal detector, which is used to perform photoelectric conversion on the received n-way transmission communication optical signals; A communication signal amplifier, which is used to amplify and shape the n-channel electrical signals output by the communication signal detector and output an n-channel high-speed communication receiving signal; It is characterized by further comprising: An OTDR signal emission drive array, which is used to output n narrow pulse electrical signals to drive the second laser array to emit n OTDR optical pulses with a wavelength of λ2, where λ2≠λ1; A wavelength division multiplexing optical path array, which is used to inject n channels of the communication optical signals and n channels of the OTDR optical pulses into n transmitting optical fibers respectively, and receive the back-reflected and scattered optical signals generated when the OTDR optical pulses propagate in the transmitting optical fibers; An OTDR detector, which is used to perform photoelectric conversion on n-path back-reflected and scattered light signals output by the wavelength division multiplexing optical path array; An OTDR processing circuit, which is used to amplify, shape, filter, and perform analog-to-digital conversion on n-channel electrical signals output by the OTDR detector, and then output backward signal strength data that varies with time; A microcontroller generates data showing a variation of the backward signal strength with the optical fiber distance according to the backward signal strength data showing a variation with time, so as to generate an OTDR test curve and / or an event table.

2. The multi-channel wavelength division multiplexing optical communication module with integrated OTDR function according to claim 1, characterized in that: The transmitting optical fiber is a multimode optical fiber; The microcontroller controls the first laser array to output a communication optical signal having a wavelength that is the same as or close to the communication band of the multimode optical fiber according to the communication band of the multimode optical fiber; The microcontroller controls the second laser array to output a laser signal with a wavelength of λ2 according to the wavelength λ2 of the required OTDR optical pulse for OTDR detection; The microcontroller controls the OTDR signal transmission drive array to output a narrow pulse electrical signal of nanosecond level or hundred-picosecond level, so as to drive the second laser array to output an OTDR optical pulse with a pulse width of nanosecond level or hundred-picosecond level.

3. The multi-channel wavelength division multiplexing optical communication module with integrated OTDR function according to claim 1, characterized in that: Also includes: The communication receiving optical path array is connected to n receiving optical fibers and is used to focus the n pairs of communication optical signals transmitted through the n receiving optical fibers and then inject them into the communication signal detector.

4. The multi-channel wavelength division multiplexing optical communication module with integrated OTDR function according to any one of claims 1 to 3, characterized in that: In the OTDR signal transmission drive array, n narrow pulse electrical signal generating circuits are arranged, and each of the narrow pulse electrical signal generating circuits comprises: A NOT gate, which is used to invert a pulse signal output by the microcontroller; An AND gate, which is used to generate an output pulse after performing an AND operation on the pulse signal output by the NOT gate and another pulse signal output by the microcontroller; an adjustable resistor connected between the output end of the AND gate and the second laser array, and adjusting the optical power of the optical signal emitted by the second laser array by changing the driving current applied to the second laser array; The microcontroller changes the pulse width of the output pulse generated by the AND gate by adjusting the time difference between the two pulse signals output by the microcontroller, so as to generate a narrow pulse electrical signal of nanosecond level or hundred-picosecond level.

5. The multi-channel wavelength division multiplexing optical communication module with integrated OTDR function according to claim 4, characterized in that: In the second laser array, n VCSEL lasers driven by small current are arranged, and each VCSEL laser is driven by one of the narrow pulse electrical signal generating circuits.

6. The multi-channel wavelength division multiplexing optical communication module with integrated OTDR function according to any one of claims 1 to 3, characterized in that: The wavelength division multiplexing optical path array comprises: A lens base body, on which a first groove and a second groove are formed, and an inclined surface is formed, wherein the inclined surface forms a total reflection surface; A first beam splitter, which is installed in the first groove and has two parallel and opposite first and second surfaces, wherein the first surface reflects light with a wavelength of λ1 and transmits light with a wavelength of λ2, and the second surface transmits light with a wavelength of λ2; A second beam splitter, which is installed in the second groove and has two parallel and opposite first and second surfaces, wherein the first surface semi-reflects and semi-transmits light with a wavelength of λ2, and the second surface transmits light with a wavelength of λ2; Four lens arrays, among which, The first lens array performs collimation processing on the communication optical signal with a wavelength of λ1 emitted by the first laser array, generates a parallel light beam, which is transmitted in the lens matrix, enters the first groove and is emitted to the first surface of the first beam splitter, is reflected by the first surface of the first beam splitter, and is emitted in parallel to the fourth lens array. After being focused by the fourth lens array, it enters the transmitting optical fiber; The second lens array performs collimation processing on the OTDR light pulses with a wavelength of λ2 emitted by the second laser array, generates a parallel light beam which is transmitted in the lens matrix, enters the second groove and is emitted to the first surface of the second beam splitter, is reflected by the first surface of the second beam splitter, is emitted in parallel to the second surface of the first beam splitter, is transmitted through the first beam splitter, is emitted in parallel to the fourth lens array, is focused by the fourth lens array, and enters the transmitting optical fiber; The fourth lens array performs collimation processing on the back-reflected and scattered light signals returned through the transmitting optical fiber, generates a parallel light beam that enters the lens base, and then transmits through the first beam splitter and the second beam splitter, and then is directed parallel to the inclined surface of the lens base, and after being reflected by the inclined surface, it is directed parallel to the third lens array, and after being focused by the third lens array, it is directed to the OTDR detector for photoelectric conversion.

7. The multi-channel wavelength division multiplexing optical communication module with integrated OTDR function according to claim 6, characterized in that: The first groove is arranged in parallel with the second groove, and the second groove is located between the first groove and the inclined surface.

8. The multi-channel wavelength division multiplexing optical communication module with integrated OTDR function according to claim 7, characterized in that: The first beam splitter is installed in the first groove at an angle, forming an angle of 45° with the bottom surface of the first groove; The second beam splitter is installed in the second groove at an angle, forming an angle of 45° with the bottom surface of the second groove.

9. The multi-channel wavelength division multiplexing optical communication module with integrated OTDR function according to claim 7, characterized in that: The four groups of lens arrays are respectively arranged on two adjacent outer sides of the lens base, one of which is adjacent to the bottom surfaces of the first groove and the second groove, on which the first group of lens arrays, the second group of lens arrays and the third group of lens arrays are arranged, and the arrangement positions of the three groups of lens arrays correspond one by one to the positions of the first groove, the second groove and the inclined surface respectively; the other outer side surface of the lens base is adjacent to the first surface of the first beam splitter, on which the fourth group of lens arrays is arranged.

10. The multi-channel wavelength division multiplexing optical communication module integrated with OTDR function according to claim 6, characterized in that: In the four lens arrays, n lenses are respectively arranged at intervals and do not interfere with each other.

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