Method for integrating optical link detection function in optical module and optical module

Abstract

The invention discloses a method for integrating an optical link detection function in an optical module and the optical module, a GPIO (General Purpose Input / Output) port of an optical module control chip emits an optical pulse to drive a laser to emit light, a reflected signal of an optical link is obtained by virtue of the support of an internal optical path of the optical module, and meanwhile, an internal low-speed ADC (Analog to Digital Converter) is started, so that clock synchronization of emission and detection is realized; and then, through phase shift emission and multiple test data splicing, a high-speed sampling rate is completed through a low-speed ADC, and the function of an OTDR can be integrated in an optical module while an optical link detection module is not added.

Description

Technical Field

[0001] The invention belongs to the technical field of optical fiber communication processing, and in particular relates to a method for integrating an optical link detection function in an optical module and an optical module. Background Art

[0002] In the field of optical communications, OTDR (optical time-domain reflectometer) equipment is mostly used to diagnose and maintain optical fiber links. OTDR equipment is a handheld instrument with a large size. The transmission and sampling circuits are generally a combination of high-speed FPGA and high-speed ADC. One of its core functions is high-speed sampling of signals.

[0003] Some special application scenarios require the integration of optical link detection functions in optical modules. Currently, the integration of optical modules is getting higher and higher, and the circuit scheme of OTDR instruments is complex, power-hungry, and large in size, so they cannot be integrated in optical modules. Summary of the invention

[0004] The present invention proposes a method and an optical module for integrating an optical link detection function in an optical module, which utilizes limited resources in the optical module to realize signal transmission and high-speed sampling, thereby realizing that the OTDR function can be integrated in the optical module without adding an optical link detection module.

[0005] The present invention is implemented by the following technical solutions:

[0006] A method for integrating an optical link detection function in an optical module is proposed, comprising:

[0007] S1, assigns 0 to N, starts the ADC inside the optical module control chip, operates a GPIO port to send a t1ns optical pulse, controls the ADC to collect m data at T1 time interval and then stop;

[0008] S2, the value of N is increased by 1, the ADC inside the optical module control chip is started, and the delay ns later, a GPIO port is operated to send out a t1ns light pulse, and the ADC is controlled to collect m data at a T1 time interval and then stop;

[0009] S3, return to and repeat step S2 until N meets the set number of times, and the ADC collected The data are sorted according to the sampling time to obtain the collection of the optical link detection signal.

[0010] An optical module is proposed, which is configured with the method as described above, so as to realize integration of an optical link detection function in the optical module.

[0011] Compared with the prior art, the advantages and positive effects of the present invention are: the method and optical module for integrating the optical link detection function in the optical module proposed by the present invention emit light pulses through the GPIO port of the optical module control chip to drive the laser to emit light, obtain the reflection signal of the optical link with the support of the internal optical path of the optical module, and start the internal low-speed ADC at the same time to achieve clock synchronization of transmission and measurement, and then through phase-shifted transmission and multiple test data splicing, a high-speed sampling rate is achieved through a low-speed ADC, and the OTDR function can be integrated into the optical module without adding an optical link detection module.

[0012] Other features and advantages of the present invention will become more apparent after reading the detailed description of the embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0014] Figure 1 The present invention provides a method for integrating an optical link detection function into an optical module;

[0015] Figure 2 This is one of the timing diagrams of integrating the optical link detection function in the optical module proposed by the present invention;

[0016] Figure 3 This is the second timing diagram of integrating the optical link detection function in the optical module proposed by the present invention;

[0017] Figure 4 This is the third timing diagram of integrating the optical link detection function in the optical module proposed by the present invention. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] The present invention aims to use the internal control chip of the optical module to emit light pulses and start ADC measurement at the same time, so as to achieve clock synchronization between emission and measurement, and then achieve high-speed sampling through low-speed ADC by means of phase-shifted emission and multiple test data splicing, thereby improving positioning accuracy and realizing the optical fiber detection function with limited resources inside the optical module. Specifically, the GPIO port of the control chip is used to drive the laser to emit light, and then with the support of the internal optical path of the optical module, the reflection signal of the optical link is obtained, the reflection signal is converted into a current signal by the PD, and after being amplified by the amplifier, the reflection signal is measured by the low-speed ADC provided by the control chip, and then the continuous reflection signal of the entire optical link is obtained through the algorithm, so as to achieve a high-speed sampling rate and a positioning accuracy of 50 cm. Compared with the method of using a dedicated driver chip to drive the laser in the OTDR detection circuit, the present invention abandons the dedicated driver chip, uses software to directly control the GPIO port of the control chip, outputs a narrow electrical pulse signal to drive the laser to emit a light pulse, and the light pulse enters the optical fiber link through the optical device, and generates a reflection signal when encountering the optical fiber connection, break, defect, end face and tail end. After the backward reflection signal is photoelectrically converted by the detector and amplified by the amplifier circuit, it is sampled by the ADC integrated in the control chip to realize the detection of the backward signal.

[0020] A GPIO port of the control chip outputs a narrow electrical pulse signal to drive the laser to emit an optical pulse to realize the output of the OTDR detection signal. The width of the optical pulse is t1ns (taking 5ns as an example); when the optical pulse enters the optical fiber link and encounters the optical fiber connection, break, defect, end face and tail end, a reflection signal is generated. After the backward reflection signal is photoelectrically converted by the detector and amplified by the amplifier circuit, the width is widened to t2ns (when the optical pulse width of the detection signal is 5ns, it is widened to about 6ns). This signal is the collected signal and is sampled by the ADC integrated in the control chip. The sampling rate of the ADC integrated in the control chip is 2Msps, and this low sampling rate cannot collect a signal with a width of 6ns. In view of this, this patent adopts a phase shift splicing method to use an ADC with a sampling rate of 2Msps to sample a 6ns width signal and detect the backward signal.

[0021] Specifically, Figure 1 As shown, the method for integrating the optical link detection function in the optical module proposed by the present invention includes:

[0022] S1: Assign 0 to N, start the ADC inside the optical module control chip, operate a GPIO port to send a t1ns light pulse, and control the ADC to collect m data at T1 time intervals and then stop.

[0023] Assume that the internal ADC is started at time t0, and then a GPIO port is immediately operated to send out a t1ns optical pulse. After the pulse is reflected by the optical link, the measured signal is generated at time t1, and the width of the measured signal is widened to t2ns. Among them, time t1 is uncertain and depends on the position of the abnormal point of the optical link.

[0024] T1 is the time interval at the internal ADC sampling frequency.

[0025] S2: The value of N is increased by 1, the ADC inside the optical module control chip is started, and the delay ns later, a GPIO port is operated to send out a t1ns light pulse, which controls the ADC to collect data m times at T1 time interval and then stop.

[0026] That is, after t0+mT1 time, start ADC again and delay ns later, a GPIO port is operated to send out a t1ns optical pulse. After being reflected by the optical link, the measured signal is generated at time ti, and the width of the measured signal is widened to t2ns. Among them, time ti is uncertain and depends on the position of the abnormal point of the optical link.

[0027] S3: Return and repeat step S2 until N meets the set number of times, and the ADC collected The data are sorted according to the sampling time to obtain the collection of the optical link detection signal.

[0028] Should The sampling time interval of each data is t1ns, t1<t2, so the signal with a time width of t2 can be guaranteed to be collected, thus realizing the collection of the pulse width of t2.

[0029] The method proposed by the present invention is described in detail below with a specific embodiment.

[0030] Take t1=5ns, measured signal width t2=6ns, and the sampling frequency of the ADC inside the optical module control chip as 2Msps. Figures 2 to 4 As shown:

[0031] Timing (1) is that at time t0, the control chip sends a 5ns optical pulse from a GPIO port. After the optical pulse is reflected by the optical link, the measured signal is generated at time t1, and the signal width is widened to 6ns.

[0032] Timing (2) starts ADC acquisition at time t0. The 2Msps ADC acquires data once every T1=500ns, and stops after acquiring m=10 times, that is, after 4500ns.

[0033] Timing (3) and (4) are that ADC acquisition starts after (t0+4500)ns, for example, (t0+4505)ns (t01 in the figure), and then a light pulse is emitted at a delay of 5ns. After the light pulse is reflected by the optical link, a measured signal is generated at t2, and the signal width is widened to 6ns.

[0034] Since the interval between the light pulse emission time and the measured signal reflection time is fixed, the timings (3) and (4) can be equivalent to being simultaneously shifted left by 5ns, becoming timings ⑤ and ⑥.

[0035] The sequence (2) and (6) are spliced ​​together to form the sequence (7). It can be seen that the acquisition frequency of the signal (1) is doubled. According to this method, each time the ADC is started, the emission pulse is delayed by 5ns compared to the time when the light pulse was emitted after the last ADC was started. After 99 delays, the second data collected for the 100th time is the data at t0+5ns. After all the data are spliced ​​together, it can be guaranteed that there is at least one sampling point within every 5ns, so the 6ns measured signal can be guaranteed to be collected.

[0036] The present invention drives the laser to emit light by emitting light pulses through the GPIO port of the optical module control chip, obtains the reflected signal of the optical link with the support of the internal optical path of the optical module, and simultaneously starts the internal low-speed ADC to achieve clock synchronization of transmission and measurement, and then transmits through phase shifting and splices multiple test data, thereby achieving a sampling rate of 200Msps through a 2Msps ADC, and achieving the fiber optic detection function by using the limited resources inside the optical film block.

[0037] It should be noted that, in the specific implementation process, the above-mentioned control part can be implemented by a hardware processor executing computer execution instructions in software form stored in the memory, which will not be elaborated here, and the programs corresponding to the actions performed by the above-mentioned control circuit can be stored in the computer-readable storage medium of the system in software form, so that the processor can call and execute the operations corresponding to the above-mentioned modules.

[0038] The computer-readable storage medium mentioned above may include volatile memory, such as random access memory; may also include non-volatile memory, such as read-only memory, flash memory, hard disk or solid-state drive; may also include a combination of the above types of memory.

[0039] The processor mentioned above may also be a general term for multiple processing elements. For example, the processor may be a central processing unit, or other general-purpose processors, digital signal processors, application-specific integrated circuits, field programmable gate arrays or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc., or may be a dedicated processor.

[0040] It should be pointed out that the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A method for integrating an optical link detection function in an optical module, characterized in that: include: S1, assigns 0 to N, starts the ADC inside the optical module control chip, operates a GPIO port to send a t1ns optical pulse, controls the ADC to collect m data at T1 time interval and then stop; S2, the value of N is increased by 1, the ADC inside the optical module control chip is started, and the delay ns later, a GPIO port is operated to send out a t1ns light pulse, and the ADC is controlled to collect m data at a T1 time interval and then stop; S3, return to and repeat step S2 until N meets the set number of times, and the ADC collected The data are sorted according to the sampling time to obtain the collection of the optical link detection signal.

2. An optical module, characterized in that: The optical module is configured with the method according to claim 1 to realize integration of an optical link detection function in the optical module.

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