CN216490514U - Low duty cycle pulse signal transmission device and system - Google Patents
Low duty cycle pulse signal transmission device and system Download PDFInfo
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- CN216490514U CN216490514U CN202122951166.XU CN202122951166U CN216490514U CN 216490514 U CN216490514 U CN 216490514U CN 202122951166 U CN202122951166 U CN 202122951166U CN 216490514 U CN216490514 U CN 216490514U
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Abstract
The utility model provides a transmission device and a system of a low duty ratio pulse signal, wherein the transmission device comprises an optical transmitter and an optical receiver; the optical transmitter is connected with the transmitting terminal equipment; the optical transmitter is connected with the optical receiver through an optical fiber line; the optical transmitter is used for carrying out 'dark pulse' modulation on the low-duty-ratio pulse electrical signal sent by the sending terminal equipment and carrying out electro-optical conversion on the modulated low-duty-ratio pulse electrical signal to obtain a low-duty-ratio pulse optical signal; the optical receiver is connected with the receiving terminal equipment; the optical receiver performs photoelectric conversion on the low-duty-ratio pulse optical signal transmitted by the optical fiber line to obtain a transmitted low-duty-ratio pulse electrical signal, and transmits the transmitted low-duty-ratio pulse electrical signal to the receiving terminal equipment. The optical transmitter of the utility model carries out 'dark pulse' modulation on the time-frequency electric signal sent by the sending terminal equipment, and has the advantages of optical fiber line attenuation change resistance, stable transmission time delay and low cost.
Description
Technical Field
The utility model relates to the technical field of optical fiber transmission, in particular to a low-duty-ratio pulse signal transmission device and system.
Background
In many large measurement networks, low duty cycle pulse devices are required for time synchronization, and a central device sends time synchronization pulses or measurement start pulses, typically as transmission Pulse Per Second (PPS) signals, to other end devices. Such transmitted signals are characterized by a very low duty cycle, in some cases a pulse signal with a width of tens of ns is emitted within a time interval of one second, and the duty cycle can be as low as 10E-7. When the optical fiber is used as a transmission medium of a low duty ratio pulse signal, the length of the optical fiber ranges from several meters to tens of kilometers, and the transmission delay of the signal is changed due to the influence of various environmental factors. This solution is suitable when the length of the optical fiber is long, but for the short distance between the equipments, the length of the optical fiber is within thousands of meters, even tens of meters, the above solution is too complex and costly.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a transmission device and a transmission system of a low-duty-ratio pulse signal, which have the advantages of resistance to attenuation change of an optical fiber circuit, stable transmission delay and low cost.
In order to achieve the purpose, the utility model provides the following scheme:
a low duty cycle pulse signal transmission apparatus, comprising:
an optical transmitter and an optical receiver;
the optical transmitter is connected with transmitting terminal equipment; the optical transmitter is connected with the optical receiver through an optical fiber line; the optical transmitter is used for carrying out dark pulse modulation on the low-duty-ratio pulse electrical signal sent by the sending terminal equipment and carrying out electro-optical conversion on the modulated low-duty-ratio pulse electrical signal to obtain a low-duty-ratio pulse optical signal;
the optical receiver is connected with receiving terminal equipment; and the optical receiver performs photoelectric conversion on the low-duty-ratio pulse optical signal transmitted by the optical fiber line to obtain a transmitted low-duty-ratio pulse electrical signal, and transmits the transmitted low-duty-ratio pulse electrical signal to receiving terminal equipment.
Optionally, the optical transmitter specifically includes:
the device comprises a pulse signal shaping circuit, a laser current driver, a laser, an automatic power controller and a first photoelectric detector;
the input end of the pulse signal shaping circuit is connected with the transmitting terminal equipment; the pulse signal shaping circuit, the laser current driver and the laser are sequentially connected; the output end of the laser is connected with one end of the optical fiber circuit;
the first photoelectric detector is connected with the automatic power controller; the first photoelectric detector is used for detecting a backward optical signal of the laser;
the automatic power controller is used for amplifying the back light signal and controlling the current drive of the laser according to the amplified back light signal to form the closed-loop control of the automatic light power.
Optionally, the optical receiver specifically includes:
the second photoelectric detector, the preamplifier, the controllable gain amplifier, the comparison amplifier and the automatic gain controller;
the input end of the preamplifier is connected with the other end of the optical fiber circuit; the second photoelectric detector, the preamplifier, the controllable gain amplifier and the comparison amplifier are connected in sequence; the output end of the comparison amplifier is connected with the receiving terminal equipment;
the input end of the automatic gain controller is connected with the output end of the controllable gain amplifier; the output end of the automatic gain controller is connected with the control end of the controllable gain amplifier; the automatic gain controller is used for amplifying the direct current component of the output signal of the controllable gain amplifier and controlling the gain of the controllable gain amplifier according to the amplified direct current component to form automatic gain closed-loop control.
Optionally, the optical receiver further includes:
a filter circuit;
the input end of the filter circuit is connected with the output end of the controllable gain amplifier;
and the output end of the filter circuit is connected with the input end of the automatic gain controller.
A transmission system for low duty cycle pulsed signals, comprising:
a transmitting terminal device, a plurality of transmission devices of the low duty ratio pulse signals, and a plurality of receiving terminal devices;
the transmitting terminal equipment is respectively connected with the plurality of transmission devices; and the plurality of transmission devices and the plurality of receiving terminal devices are respectively connected in a one-to-one correspondence manner.
According to the specific embodiment provided by the utility model, the utility model discloses the following technical effects:
the utility model provides a transmission device and a system of low duty ratio pulse signals, wherein the transmission device comprises an optical transmitter and an optical receiver; the optical transmitter is connected with the transmitting terminal equipment; the optical transmitter is connected with the optical receiver through an optical fiber circuit; the optical transmitter is used for carrying out 'dark pulse' modulation on the low-duty-ratio pulse electrical signal sent by the sending terminal equipment and carrying out electro-optical conversion on the modulated low-duty-ratio pulse electrical signal to obtain a low-duty-ratio pulse optical signal; the optical receiver is connected with the receiving terminal equipment; the optical receiver performs photoelectric conversion on the low-duty-ratio pulse optical signal transmitted by the optical fiber line to obtain a transmitted low-duty-ratio pulse electrical signal, and transmits the transmitted low-duty-ratio pulse electrical signal to the receiving terminal equipment. The optical transmitter of the utility model carries out 'dark pulse' modulation on the time-frequency electric signal sent by the sending terminal equipment, and has the advantages of optical fiber line attenuation change resistance, stable transmission time delay and low cost.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.
FIG. 1 is a schematic structural diagram of a transmission apparatus for modulating a low duty cycle pulse signal by "bright pulses" in the prior art;
fig. 2 is a schematic diagram illustrating a change in amplitude of a pulse signal output by a transmission device for modulating a low-duty-ratio pulse signal by a "bright pulse" in the prior art when the attenuation of an optical fiber changes;
fig. 3 is a schematic diagram illustrating a change of an amplitude of a pulse signal output by a transmission device for modulating a low-duty-ratio pulse signal by a "bright pulse" in the prior art after an optical fiber attenuation is increased by 5 dB;
FIG. 4 is a schematic structural diagram of a transmission apparatus for modulating a low duty cycle pulse signal by a "dark pulse" according to an embodiment of the present invention;
description of the drawings: 1-a pulse signal shaping circuit; 2-laser current driver; 3-a laser; 4-an automatic power controller; 5-a first photodetector; 6-a second photodetector; 7-a preamplifier; 8-a controllable gain amplifier; 9-comparison amplifier 10 automatic gain controller.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The utility model aims to provide a transmission device and a transmission system of a low-duty-ratio pulse signal, which have the advantages of resistance to attenuation change of an optical fiber circuit, stable transmission delay and low cost.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
FIG. 4 is a schematic structural diagram of a transmission apparatus for modulating a low duty cycle pulse signal by a "dark pulse" according to an embodiment of the present invention; as shown in fig. 4, the present invention provides a transmission apparatus for a low duty ratio pulse signal, including:
an optical transmitter and an optical receiver;
the optical transmitter is connected with the transmitting terminal equipment; the optical transmitter is connected with the optical receiver through an optical fiber circuit; the optical transmitter is used for carrying out 'dark pulse' modulation on the low-duty-ratio pulse electrical signal sent by the sending terminal equipment and carrying out electro-optical conversion on the modulated low-duty-ratio pulse electrical signal to obtain a low-duty-ratio pulse optical signal;
the optical receiver is connected with the receiving terminal equipment; the optical receiver performs photoelectric conversion on the low-duty-ratio pulse optical signal transmitted by the optical fiber line to obtain a transmitted low-duty-ratio pulse electrical signal, and transmits the transmitted low-duty-ratio pulse electrical signal to the receiving terminal equipment.
Wherein, the optical transmitter specifically includes:
the device comprises a pulse signal shaping circuit 1, a laser current driver 2, a laser 3, an automatic power controller 4 and a first photoelectric detector 5;
the input end of the pulse signal shaping circuit is connected with the transmitting terminal equipment; the pulse signal shaping circuit, the laser current driver and the laser are sequentially connected; the output end of the laser is connected with one end of the optical fiber circuit;
the first photoelectric detector is connected with the automatic power controller; the first photoelectric detector is used for detecting a backward optical signal of the laser;
the automatic power controller is used for amplifying the back light signal and controlling the current drive of the laser according to the amplified back light signal to form the closed-loop control of the automatic light power.
The optical receiver specifically includes:
a second photoelectric detector 6, a preamplifier 7, a controllable gain amplifier 8, a comparison amplifier 9 and an automatic gain controller 10;
the input end of the preamplifier is connected with the other end of the optical fiber circuit; the second photoelectric detector, the preamplifier, the controllable gain amplifier and the comparison amplifier are connected in sequence; the output end of the comparison amplifier is connected with the receiving terminal equipment;
the input end of the automatic gain controller is connected with the output end of the controllable gain amplifier; the output end of the automatic gain controller is connected with the control end of the controllable gain amplifier; the automatic gain controller is used for amplifying the direct current component of the output signal of the controllable gain amplifier and controlling the gain of the controllable gain amplifier according to the amplified direct current component to form automatic gain closed-loop control.
Further, the optical receiver further includes:
a filter circuit (not shown herein);
the input end of the filter circuit is connected with the output end of the controllable gain amplifier;
the output end of the filter circuit is connected with the input end of the automatic gain controller.
As shown in fig. 1, the current pulse optical fiber transceiver solution includes two parts: the pulse signal shaping circuit and the laser current driving circuit form an optical transmitter; the optical receiver is composed of a preamplifier and a comparison amplifier. The optical transmitter completes the electric-optical conversion, and the optical receiver completes the optical-electric conversion and the pulse regeneration.
In the current optical fiber transceiver technical scheme, an optical signal modulation mode of a "bright pulse" mode is adopted, that is: when the pulse occurs, the logic signal is corresponding to '1', and the logic signal is corresponding to 'high optical power level'; when no pulse occurs, a "0" logic signal corresponds to a "no light power level or an extremely low light power level". In an optical transmitter, when a pulse signal-1 signal appears at an input end, a pulse signal shaping circuit generates the 1 signal, so that a laser current driving circuit generates current to drive a laser to emit light and generate an optical pulse signal corresponding to the pulse signal; when the input end does not generate a pulse signal, namely a '0' signal, the pulse signal shaping circuit generates a '0' signal, so that the laser current driving circuit does not output current to drive the laser, the laser does not emit light, and the output light power is 0 or extremely low light power level.
The optical pulse optical signal is transmitted to a photoelectric detector in the optical-electric conversion through an optical fiber to be converted into light current, the light current is amplified by a preamplifier, the obtained pulse signal Vp is regenerated by a comparison amplifier circuit, and finally regenerated pulse output is obtained.
In the above process, the optical pulse signal modulated in the "bright pulse" manner is used, and when the pulse duty ratio is low, it is inconvenient to detect the pulse amplitude level in the output optical signal in the optical transmitter to implement the automatic optical power control; in an optical receiver, it is not convenient either to implement automatic gain control to control pulse amplitude stability or to detect well the pulse amplitude level to automatically adjust the comparison threshold level of the comparison amplifier. Therefore, when the pulse is regenerated, the comparison amplifier can only perform comparison amplification by using a fixed comparison threshold level to regenerate the pulse signal, as shown in fig. 2 and 3.
Compare threshold level V, FIG. 2thTaking a fixed value, e.g. pulse signal V p1/6 of (1). When the attenuation of the optical fiber changes, the amplitude of the pulse signal output by the preamplifier changes correspondingly, and as in the example of fig. 3, after the attenuation of the optical fiber is increased by 5dB, the amplitude of the pulse signal changes from VpIs reduced to V'p，V'p＝Vp/3. Due to comparison of threshold levels VthThe time position of the rising edge of the regenerated pulse signal obtained by the comparison amplifier is changed to be a fixed value, the change is delta t, and the magnitude of delta t is related to the change of the amplitude of the pulse signal and the rising edge rate of the pulse signal. When the amplitude of the pulse signal varies by a large amount, e.g., 10dB, and the rising edge rate of the pulse signal is low, e.g., 1ns, in the above example, Δ t can reach 600ps or more. In some applications, transmission delay variations of hundreds of ps exceed the tolerance.
As shown in fig. 4, the optical fiber transceiver of the present invention includes two parts: an optical transmitter and an optical receiver. The optical transmitter performs the electrical-to-optical conversion, and the optical receiver performs the optical-to-electrical conversion and the pulse regeneration.
The optical transmitter includes: pulse signal shaping, laser current driving, automatic power control, a laser and a first photoelectric detector; the pulse signal shaping, the laser current driving and the laser are sequentially connected, the first photoelectric detector detects a backward light signal of the laser, and the backward light signal is amplified by the automatic power control circuit and then controls the laser current driving circuit to form automatic light power control.
The optical receiver includes: the second photoelectric detector, the preamplifier, the controllable gain amplifier, the comparison amplifier and the automatic gain control; the second photoelectric detector, the preamplifier, the controllable gain amplifier and the comparison amplifier are sequentially connected, the automatic gain control circuit filters an output signal of the controllable gain amplifier, amplifies an obtained direct-current component signal and outputs the amplified direct-current component signal to a gain control input end of the controllable gain amplifier to form automatic gain closed-loop control, the output signal of the controllable gain amplifier is stable and unchanged, and the comparison amplifier performs pulse regeneration by adopting a fixed comparison threshold value.
In the device, a light signal modulation mode of a 'dark pulse' mode is adopted, a pulse signal appears, corresponds to a '1' logic signal and corresponds to 'no light power level or extremely low light power level'; no pulse signal is present, corresponding to a "0" logic signal, corresponding to a "high optical power level". When a pulse signal-1 signal appears at the input end, the pulse signal shaping circuit generates a 1 signal, the laser current driving circuit does not generate current to drive the laser, the laser does not emit light or only emits light with low power, and the output light power is 0 or extremely low light power level; when the input end does not have a pulse signal, namely a '0' signal, the pulse signal shaping circuit generates a '0' signal, the laser current driving circuit outputs current to drive the laser to emit light, and the output light power is high light power.
After the optical signal modulation mode of the 'dark pulse' mode is adopted, the pulse duty ratio is very low and is lower than 10E-3At the end of the optical transmitter, the optical signal output by the optical transmitter is a high-power optical signal similar to direct current in most of time; when a pulse signal is present, the optical transmitter outputs an optical power at a lower value, such as less than-30 dBm. Thus, it is easy to adopt the back-light signal DC signal amplifying circuit to form the automatic optical power control circuit, so that the average optical power level of the optical signal outputted by the optical transmitter tends to a stable value, such as 0dBm, and the amplitude level value of the optical pulse signal is also approximately equal to the average power level value of the optical signal. Since the amplitude level of the optical pulse is approximately equal to the average output optical power of the laser, the amplitude of the pulse signal in the optical signal can be stabilized by controlling the average output optical power of the optical transmitter to be stable.
After the optical signal modulation mode of the "dark pulse" mode is adopted, in the embodiment, a preamplifier and a controllable gain amplifier in the optical receiver simultaneously amplify a direct current signal and a pulse signal contained in the optical signal, the level of the pulse signal is approximately equal to the level of the direct current signal, and the amplitude level of the pulse signal is obtained by detecting the direct current level of the received optical signal; the automatic gain control circuit filters the output signal of the controllable gain amplifier and amplifies the obtained direct current component signal, then the signal is output to the gain control input end of the controllable gain amplifier to form automatic gain closed-loop control, so that the output signal of the controllable gain amplifier is stable and unchanged, even if the comparison amplifier uses a fixed comparison threshold, the ratio of the amplitude level of the pulse input signal to the comparison threshold level can still be kept almost unchanged, the rising edge time position of the regenerated pulse signal regenerated by the comparison amplifier does not change along with the change of the input pulse signal level, the influence of the amplitude level change of the pulse input signal on the transmission delay is greatly weakened, even if a device with lower speed and smaller bandwidth is adopted, when the loss of the optical fiber line changes, the transmission delay can be ensured to be hardly changed along with the change of the loss of the optical fiber line.
In addition, the present invention also provides a transmission system of a low duty ratio pulse signal, the transmission system comprising:
a transmitting terminal device, a plurality of transmission devices of the low duty ratio pulse signals, and a plurality of receiving terminal devices;
the transmitting terminal equipment is respectively connected with a plurality of transmission devices; the plurality of transmission devices and the plurality of receiving terminal devices are respectively connected in a one-to-one correspondence manner.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. Meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the utility model.
Claims (5)
1. A transmission apparatus for low duty cycle pulse signals, the transmission apparatus comprising:
an optical transmitter and an optical receiver;
the optical transmitter is connected with transmitting terminal equipment; the optical transmitter is connected with the optical receiver through an optical fiber line; the optical transmitter is used for carrying out 'dark pulse' modulation on the low-duty-ratio pulse electrical signal sent by the sending terminal equipment and carrying out electro-optical conversion on the modulated low-duty-ratio pulse electrical signal to obtain a low-duty-ratio pulse optical signal;
the optical receiver is connected with receiving terminal equipment; and the optical receiver performs photoelectric conversion on the low-duty-ratio pulse optical signal transmitted by the optical fiber line to obtain a transmitted low-duty-ratio pulse electrical signal, and transmits the transmitted low-duty-ratio pulse electrical signal to receiving terminal equipment.
2. The apparatus for transmitting a low duty cycle pulse signal according to claim 1, wherein the optical transmitter specifically comprises:
the device comprises a pulse signal shaping circuit, a laser current driver, a laser, an automatic power controller and a first photoelectric detector;
the input end of the pulse signal shaping circuit is connected with the transmitting terminal equipment; the pulse signal shaping circuit, the laser current driver and the laser are sequentially connected; the output end of the laser is connected with one end of the optical fiber circuit;
the first photoelectric detector is connected with the automatic power controller; the first photoelectric detector is used for detecting a backward optical signal of the laser;
the automatic power controller is used for amplifying the back light signal and controlling the current drive of the laser according to the amplified back light signal to form the closed-loop control of the automatic light power.
3. The apparatus for transmitting a low duty cycle pulse signal according to claim 2, wherein the optical receiver specifically comprises:
the second photoelectric detector, the preamplifier, the controllable gain amplifier, the comparison amplifier and the automatic gain controller;
the input end of the preamplifier is connected with the other end of the optical fiber circuit; the second photoelectric detector, the preamplifier, the controllable gain amplifier and the comparison amplifier are connected in sequence; the output end of the comparison amplifier is connected with the receiving terminal equipment;
the input end of the automatic gain controller is connected with the output end of the controllable gain amplifier; the output end of the automatic gain controller is connected with the control end of the controllable gain amplifier; the automatic gain controller is used for amplifying the direct current component of the output signal of the controllable gain amplifier and controlling the gain of the controllable gain amplifier according to the amplified direct current component to form automatic gain closed-loop control.
4. The apparatus for transmitting a low duty cycle pulse signal according to claim 3, wherein said optical receiver further comprises:
a filter circuit;
the input end of the filter circuit is connected with the output end of the controllable gain amplifier;
and the output end of the filter circuit is connected with the input end of the automatic gain controller.
5. A transmission system for low duty cycle pulse signals, the transmission system comprising:
a transmitting terminal device, a plurality of transmission devices of low duty cycle pulse signals according to any one of claims 1 to 4, and a plurality of receiving terminal devices;
the transmitting terminal equipment is respectively connected with the plurality of transmission devices; and the plurality of transmission devices and the plurality of receiving terminal devices are respectively connected in a one-to-one correspondence manner.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122951166.XU CN216490514U (en) | 2021-11-29 | 2021-11-29 | Low duty cycle pulse signal transmission device and system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122951166.XU CN216490514U (en) | 2021-11-29 | 2021-11-29 | Low duty cycle pulse signal transmission device and system |
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| Publication Number | Publication Date |
|---|---|
| CN216490514U true CN216490514U (en) | 2022-05-10 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202122951166.XU Active CN216490514U (en) | 2021-11-29 | 2021-11-29 | Low duty cycle pulse signal transmission device and system |
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| Country | Link |
|---|---|
| CN (1) | CN216490514U (en) |
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- 2021-11-29 CN CN202122951166.XU patent/CN216490514U/en active Active
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