CN1972158A - Measuring system and method for optical fiber network - Google Patents

Abstract

A measurement system of an optical fiber network having a plurality of network units and an optical line terminal includes a signal generation device, a signal distribution device, and a measurement device, the signal generation device generating data signals and control signals and sending the data signals to the network units. The signal distribution device sends a control signal to one of the network elements at a first time and sends a control signal to another one of the network elements at a second time. And after receiving the control signal, the network unit sends the data signal to the optical line terminal, and the measuring device measures the data signal received by the optical line terminal.

Description

Measuring system and method for optical fiber network

technical field

The invention relates to a measuring system and a measuring method, in particular to a measuring system and a measuring method of an optical fiber network.

Background technique

With the rapid development of the Internet, the user's demand for bandwidth has also increased significantly. Therefore, the optical fiber network with high bandwidth has become one of the best choices to solve the network bandwidth.

Fig. 1 is a schematic diagram of an existing optical fiber network. Generally speaking, this optical fiber network is a passive optical network (Passive Optical Network, PON), which is a point-to-multipoint (P2MP) structure. The optical fiber network 1 basically has a plurality of optical network units (Optical Network Unut, ONU) 11 and optical line terminal (Optical Line Terminal, OLT) 12, wherein, the optical fiber network 1 can adopt time division multiple access (Time Division Multiple Access, TDMA) Therefore, after the network units 11 of the optical fiber network 1 complete the registration, they are each assigned to a time slot (Time Slot) as an exclusive sending time, so that each network unit 11 can only send packets in the exclusive time slot, so as to avoid Data collision occurs.

Generally speaking, when it is desired to test the optical fiber network 1 (for example, bit error rate, sensitivity, etc.), a signal generating device 13 is usually configured at each network unit 11 to provide a control signal 131 and a data signal 132, and the two Or sent to these network units 11 synchronously. Among them, the control signal 131 is used to control the network unit 11, so that it converts the data signal 132 into an optical signal 131' and transmits it to the optical line terminal 12, and configures the measuring device 14 at the optical line terminal 12. When the optical line terminal 12 After receiving the optical signal 131' transmitted from these network units 11, the optical signal 131' is converted into a corresponding electrical signal 131", and then the electrical signal 131" is measured by the measuring device 14, thereby judging the status of the optical fiber network 1 sensitivity and bit error rate. However, the above-mentioned measurement method requires a plurality of signal generating devices 13 to generate the control signal 131 and the data signal 132 respectively for measurement. Therefore, if the optical fiber network 1 has 32 network units 11, 32 signal generating devices 13 will be used. Only the device 13 can perform the measurement of the optical fiber network, however, the signal generating device 13 is relatively expensive equipment, therefore, the use of the above method will result in an increase of the overall measurement cost.

Therefore, how to provide a simple optical fiber network measurement system and measurement method to achieve the effect of reducing the measurement cost is one of the current important issues.

Contents of the invention

Therefore, the object of the present invention is to provide a measurement system and method for an optical fiber network, so as to reduce the overall measurement cost.

Therefore, in order to achieve the above object, according to the measurement system of the optical fiber network of the present invention, the optical fiber network has a plurality of network units and optical line terminals, and the measurement system includes a signal generation device, a signal distribution device and a measurement device. Wherein, the signal generation device is used to generate data signals and control signals, and send the data signals to these network units, and the signal distribution device receives the control signals, and sends the control signals to one of these network units at the first time, and at the first time Second, send the control signal to another network unit among these network units; the measuring device is electrically connected to the optical line terminal, wherein, after receiving the control signal, the network unit sends the data signal to the optical line terminal, and the measuring device is connected to the optical line terminal. The data signal received by the optical line terminal is measured.

Therefore, in order to achieve the above object, according to the measurement method of the optical fiber network of the present invention, wherein the optical fiber network has a plurality of network units and optical line terminals, the measurement method includes the following steps: providing data signals to these network units respectively; And at a first time, a control signal is provided to one of these network units, and one of the network units transmits a data signal to an optical line terminal; and at a second time, a control signal is sent to one of these network units Another network unit, the network unit transmits the data signal to the optical line terminal; and measures the data signal received by the optical line terminal.

In summary, according to the measuring system and measuring method of the optical fiber network of the present invention, the signal distribution device sends the control signal to one of these network units at different times, so as to control one of these network units to transmit the data signal to the optical fiber network. The line terminal is used to simulate the transmission mode of time division multiple access, and the measuring device measures the data signal received by the optical line terminal to judge the bit error rate and sensitivity of the optical fiber network. Compared with the existing technology, this The inventive measuring system and measuring method for the optical fiber network can measure the optical fiber network only by one signal generating device, thereby achieving the effect of reducing the overall measurement cost.

Description of drawings

Fig. 1 is a schematic diagram of a measurement system of an existing optical fiber network;

Figure 2 is a schematic diagram of a measurement system for an optical fiber network according to a preferred embodiment of the present invention; and

Fig. 3 is a schematic diagram of the waveforms of the signals of the signal distribution device of the measurement system of the optical fiber network according to a preferred embodiment of the present invention.

Description of component symbols:

1-Optical fiber network 11-Network unit

12-Optical line terminal 13-Signal generating device

131-Control signal 131’-Optical signal

131”-Electrical signal 132-Data signal

14-Measuring device 2-Measuring system

3-Optical fiber network ONU ₁ ~ONU _n - network unit

OLT-optical line terminal 21-signal generating device

22-Measuring device 23-Signal distribution device

24-Frequency divider 31-Data signal

31’-optical signal 31”-electrical signal

32-Control signal 33-Clock pulse signal

D ₁ ～D _n - Trigger I ₁ ～I _n - Signal input terminal

Q ₁ ～Q _n - output terminal C _k - trigger terminal

T ₁ - first time T ₂ - second time

T ₃ - third time T ₄ - fourth time

Detailed ways

The measurement system and method for an optical fiber network according to a preferred embodiment of the present invention will be described below with reference to relevant figures.

As shown in FIG. 2 , it is a schematic diagram of a measurement system for an optical fiber network according to a preferred embodiment of the present invention.

The optical network 3 is a passive optical network (Passive Optical Network, PON), and the optical network 3 has a plurality of network units ONU ₁ -ONU _n and an optical line terminal OLT. These network units ONU ₁ -ONU _n are connected to the optical line terminal OLT by a plurality of optical fibers of different lengths to form an optical fiber network 3 .

The measurement system 2 of this embodiment can be used to measure the sensitivity and bit error rate of the optical fiber network 3 mentioned above. The measurement system 2 includes a signal generation device 21 , a measurement device 22 and a signal distribution device 23 . Wherein, the signal generating device 21 is a pulse pattern generator (Pulse Pattern Generator, PPG), which is used to generate a data signal 31 , a control signal 32 and a clock pulse signal 33 . The signal generating device 21 is connected to these network units ONU ₁ -ONU _n for providing data signals 31 and control signals 32 to these network units ONU ₁ -ONU _n . Among them, the data signal 31 is used as a data signal for testing, and the control signal 32 is used to drive these network units ONU ₁ ~ ONU _n , when these network units ONU ₁ ~ ONU _n receive the control signal 32, the data signal 31 is converted into An optical signal 31' is used to transmit the optical signal 31' to the OLT through an optical fiber. In addition, when the optical line terminal OLT receives the optical signal 31', it can generate a corresponding electrical signal 31" according to the optical signal 31'.

The measuring device 22 is electrically connected to the optical line terminal OLT for measuring the electrical signal 31 ″, and judging the sensitivity and bit error rate of the optical fiber network 3 according to the electrical signal 31 ″.

The measuring device 22 in this embodiment is a data error detection device (Error Detector, ED). The measuring device 22 is synchronized with the signal generating device 21 and compares the data signal 31 generated by the signal generating device 21 with the electrical signal 31 ″ to obtain the bit error rate and receiving sensitivity of the optical fiber network 3 .

Signal distribution device 23 receives control signal 32, and is connected with these network units ONU ₁ ～ONU _n respectively, and signal distribution device 23 is a shift register, and it is the mode that can simulate time division multiple access, at different times, for these networks One of the units ONU ₁ -ONU _n provides a control signal 32 for controlling these network units ONU ₁ -ONU _n to transmit data signals 31 to the optical line terminal OLT at different times for measurement. In this embodiment, the signal distribution device 23 has n flip-flops D ₁ -D _n .

These flip-flops D ₁ -D _n are D-type flip-flops, which have signal input terminals I _{1 -In} , at least one output terminal Q ₁ -Q _n and a trigger terminal C _k . The number of these flip-flops D ₁ -D _n depends on the number of these network units ONU ₁ -ONU _n , so that the output terminals Q ₁ -Q _n of these flip-flops D ₁ -D _n exactly correspond to these network units ONU ₁ -ONU _n .

The connection mode of the signal distribution device 23 in this embodiment is as follows: the input terminal _I1 of the flip-flop _D1 is connected to the signal generating device 21 to receive the control signal 32 . The output terminal _Q1 of flip-flop _D1 is connected to the input terminal _I2 of flip-flop _D2 , the output terminal _Q2 of flip-flop _D2 is connected to the input terminal _I3 of flip-flop _D3 , and so on until flip-flop D The output terminal Qn-1 of _{n- 1} is connected to the input terminal _In of the flip-flop _Dn . And the trigger terminals C _k of these flip-flops D ₁ -D _n are commonly connected to the clock pulse signal 33 of the signal generating device 21 as trigger signals of these flip-flops D ₁ -D _n . In addition, the network unit ONU ₁ is connected to the output terminal Q ₁ of the flip-flop D ₁ , the network unit ONU ₂ is connected to the output terminal Q ₂ of the flip-flop D 2 , and the network unit ONU ₃ is connected to the output terminal _{Q 3 of} the flip-flop D ₃ , and so on.

Due to the characteristics of the D-type flip-flop itself, the D-type flip-flop can send the signal at the input terminal to the output terminal after receiving the trigger signal (which can be a positive-edge trigger or a negative-edge trigger). Therefore, multiple D-type flip-flops When connected in series, a shift register can be formed.

FIG. 3 is a schematic diagram of the waveform of the output signal of the signal distribution device 23 . Here, for the sake of simplicity, only the output signals of the output terminals Q ₁ -Q ₄ are shown. The mode of action of the signal distribution device 23 is as follows: after the input terminal _I1 of the flip-flop _D1 receives the control signal 32 generated by the signal generating device 21 (here, it is assumed that the control signal 32 is a high-level signal), the first At time T ₁ , the output terminal Q ₁ of the flip-flop D ₁ provides the control signal 32 to the network unit ONU ₁ , and at the second time T ₂ , the output terminal Q ₂ of the flip-flop D ₂ provides the control signal 32 to the network unit ONU ₂ , at the third time T ₃ , the output terminal Q ₃ of the flip-flop D ₃ provides the control signal 32 to the network unit ONU ₃ , and at the fourth time T ₄ , the output terminal Q ₄ of the flip-flop D ₄ provides the control signal 32 to the The network unit ONU ₄ , and so on, make the signal distribution device 23 provide a control signal 32 to one of these network units ONU ₁ -ONU _n at different times, so as to simulate a time division multiple access mode.

The measurement method of the measurement system 2 of this embodiment is as follows: first, the signal generating device 21 generates a data signal 31 to these network units ONU ₁ -ONU _n . Next, the signal distribution device 23 provides the control signal 32 to the network unit ONU ₁ at the first time T ₁ to drive the network unit ONU ₁ to transmit the data signal 31 to the optical line terminal OLT. At the second time T ₂ , the signal distribution device 23 provides the control signal 32 to the network unit ONU ₂ to drive the network unit ONU ₂ to transmit the data signal 31 to the optical line terminal OLT. At the third time _T3 , the signal distribution device 23 provides the control signal 32 to the network unit ONU ₃ to drive the network unit ONU ₃ to transmit the data signal 31 to the optical line terminal OLT, and so on, so that these networks The units ONU ₁ to ONU _n respectively convert the data signal 31 into an optical signal 31' and transmit it to the optical line terminal OLT at different times, so as to achieve the analog time division multiple access mode, and the measuring device 22 then converts the optical line terminal OLT The generated electrical signal 31" is compared with the data signal 31 generated by the signal generating device 21, and the bit error rate of the optical fiber network 3 can be known. In addition, the measuring device 22 measures the power of the electrical signal 31", which can be obtained The sensitivity of the optical fiber network 3 is known.

In addition, the measurement system 2 of this embodiment further includes a frequency division device 24 connected between the signal generation device 21 and the signal distribution device 23 . Since the frequency of the clock pulse signal 33 generated by the signal generating device 21 may not match the required frequency, the frequency division device 24 can be used to divide the frequency of the clock pulse signal 33, so that after obtaining the clock pulse signal 33 of an appropriate frequency, Then send them to the signal distribution device 23 as trigger signals for these flip-flops D ₁ -D _n .

In summary, according to the measurement system and measurement method of the optical fiber network of the present invention, the signal distribution device generates corresponding control signals according to the data signals, and sends the control signals to one of these network units at different times to control One of these network units transmits the data signal to the optical line terminal to simulate the transmission mode of time division multiple access, and the measuring device measures the data signal received by the optical line terminal to judge the bit error rate and sensitivity of the optical fiber network, Compared with the existing technology, the optical fiber network measurement system and measurement method of the present invention only need one signal generating device to measure the optical fiber network, so as to achieve the effect of reducing the overall measurement cost.

The above description is only exemplary, not restrictive. Any equivalent modification or change made without departing from the spirit and scope of the present invention shall be included in the scope of the appended patent application.

Claims (17)

1. the measuring system of a fiber optic network, this fiber optic network has a plurality of network element and optical line terminal, and this measuring system comprises:

Signal generation device, it produces data-signal and control signal, and data-signal is delivered to these network element;

Signal distribution equipment, it receives control signal, and in the very first time control signal is delivered to one of these network element, another network element among control signal being delivered to these network element in second time; And

Measurement mechanism, it is electrically connected to optical line terminal, wherein, after network element receives control signal, data-signal is delivered to optical line terminal, and measurement mechanism is measured the received data-signal of optical line terminal.

2. the measuring system of fiber optic network according to claim 1, wherein, described signal generation device is the impulse waveform generator.

3. the measuring system of fiber optic network according to claim 1, wherein, described signal distribution equipment is a shift register.

4. the measuring system of fiber optic network according to claim 3, wherein, described shift register has a plurality of triggers, respectively corresponding these network element of the output of these triggers.

5. the measuring system of fiber optic network according to claim 4, wherein, described trigger system is a D flip-flop.

6. the measuring system of fiber optic network according to claim 1, wherein, described fiber optic network is an EPON.

7. the measuring system of fiber optic network according to claim 1, wherein, described measurement mechanism is a data debug device.

8. the measuring system of fiber optic network according to claim 1, wherein, described measurement mechanism is judged the sensitivity of described fiber optic network according to the received described data-signal of described optical line terminal.

9. the measuring system of fiber optic network according to claim 1, wherein, described measurement mechanism is judged the error rate of described fiber optic network according to the received described data-signal of described optical line terminal.

10. the measuring system of fiber optic network according to claim 1, wherein, described signal generation device also produces clock pulse signal to described signal distribution equipment.

11. the measuring system of fiber optic network according to claim 10 also comprises frequency divider, it is connected between described signal generation device and the described signal distribution equipment, after described clock pulse signal is carried out frequency division, delivers to described signal distribution equipment.

12. the method for measurement of a fiber optic network, wherein, fiber optic network has a plurality of network element and optical line terminal, and described method of measurement comprises the following steps:

Respectively data-signal is offered these network element;

In the very first time, provide control signal to deliver to one of these network element, and one of described network element is sent to described optical line terminal to described data-signal;

In second time, described control signal is delivered to another network element among these network element, and another network element among the described network element is sent to described optical line terminal to described data-signal; And

The described data-signal that described optical line terminal is received is measured.

13. the method for measurement of fiber optic network according to claim 12 wherein, offers the step of these network element to described control signal, is to provide described control signal by shift register.

14. the method for measurement of fiber optic network according to claim 12, wherein, described fiber optic network is an EPON.

15. the method for measurement of fiber optic network according to claim 12 wherein, to the step that the received described data-signal of described optical line terminal is measured, is by data debug device described data-signal to be measured.

16. the method for measurement of fiber optic network according to claim 12 wherein, to the step that the received described data-signal of described optical line terminal is measured, is according to described data-signal the sensitivity of described fiber optic network to be judged.

17. the method for measurement of fiber optic network according to claim 12 wherein, to the step that the received described data-signal of described optical line terminal is measured, is according to described data-signal the error rate of described fiber optic network to be judged.

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