CN113824500A - Passive optical amplification unit and multiband ultra-long span transmission system - Google Patents
Passive optical amplification unit and multiband ultra-long span transmission system Download PDFInfo
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- H04—ELECTRIC COMMUNICATION TECHNIQUE
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- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/25—Arrangements specific to fibre transmission
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/25—Arrangements specific to fibre transmission
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- H04B10/25752—Optical arrangements for wireless networks
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- H—ELECTRICITY
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- H04J14/00—Optical multiplex systems
- H04J14/02—Wavelength-division multiplex systems
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J14/00—Optical multiplex systems
- H04J14/02—Wavelength-division multiplex systems
- H04J14/0278—WDM optical network architectures
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Abstract
The invention provides a passive optical amplification unit and a multiband ultra-long span transmission system, the passive optical amplification unit comprises: the first wavelength division multiplexer, the second wavelength division multiplexer, the third wavelength division multiplexer, the fourth wavelength division multiplexer, the fifth wavelength division multiplexer, the sixth wavelength division multiplexer, the first erbium-doped optical fiber and the second erbium-doped optical fiber. Pumping light enters from the input end of the first erbium-doped fiber in the forward direction, and a first waveband optical signal passes through the first erbium-doped fiber to realize signal amplification; the pumping light reversely enters from the output end of the second erbium-doped fiber after being output by the first erbium-doped fiber and the third wavelength division multiplexer, and the second waveband optical signal realizes signal amplification after passing through the second erbium-doped fiber. The invention can simultaneously realize the transmission of two optical signals by only occupying one line fiber core, and simultaneously the pumping light does not additionally occupy the fiber core, thereby effectively prolonging the transmission distance of the ultra-long span optical fiber communication system, reducing the line laying cost, having good performance stability and long service life.
Description
Technical Field
The invention relates to the technical field of optical communication, in particular to a passive optical amplification unit and a multiband ultra-long span transmission system.
Background
With the rapid development of emerging technologies and industries such as cloud computing and big data, telecom operators and internet operations feel unprecedented pressure. As the number of connected devices increases, the amount of data generated increases greatly, and a higher bandwidth is required to meet the requirement of the network. In order to better satisfy the conditions, the computing processing of the data needs to be converged to the cloud, and in the process, the demand of data transmission also increases greatly. Therefore, on the basis of a service based on a C-Band (a Conventional Band, which represents a Conventional Band, an optical fiber shows the lowest loss in the C-Band and has a great advantage in a Long-distance transmission system), it is urgently needed to develop an L-Band (Long-wavelength Band, which is a second low-loss wavelength Band and is often used when the C-Band is not enough to meet a bandwidth requirement) service.
In the prior art, if the C-band and the L-band are needed, a fiber core is often needed to be used alone to transmit the L-band service signal light, or a fiber core is used alone to transmit the pump light of the L-band service, which causes great waste of fiber core resources and increases the construction, operation and maintenance costs.
Disclosure of Invention
In view of the above problems, it is necessary to provide a passive optical amplifying unit and a multiband ultra-long span transmission system to solve or partially solve the above problems, and the technical solutions proposed by the present invention are as follows:
a passive optical amplification unit comprising: first wavelength division multiplexer, second wavelength division multiplexer, third wavelength division multiplexer, fourth wavelength division multiplexer, fifth wavelength division multiplexer, sixth wavelength division multiplexer, first erbium-doped optical fiber and second erbium-doped optical fiber, wherein:
the input end of the first wavelength division multiplexer is used for being connected with a first transmission optical fiber, the output end of the first wavelength division multiplexer is respectively connected with a second wavelength division multiplexer and a second erbium-doped optical fiber, and the first wavelength division multiplexer is used for separating optical signals of two wave bands input from the outside into optical signals of a first wave band and optical signals of a second wave band, wherein the optical signals of the first wave band enter the second wavelength division multiplexer, and the optical signals of the second wave band enter the second erbium-doped optical fiber;
the second wavelength division multiplexer is respectively connected with the first wavelength division multiplexer, the fourth wavelength division multiplexer and the first erbium-doped optical fiber and is used for inputting a first wavelength band optical signal output by the first wavelength division multiplexer and pump light wave output by the fifth wavelength division multiplexer and transmitted by the fourth wavelength division multiplexer into the first erbium-doped optical fiber so as to realize amplification of the first wavelength band optical signal;
the third wavelength division multiplexer is respectively connected with the first erbium-doped optical fiber, the fourth wavelength division multiplexer and the sixth wavelength division multiplexer and is used for separating the amplified first wavelength band optical signal output by the first erbium-doped optical fiber and the residual pump light output by the first erbium-doped optical fiber, the amplified first wavelength band optical signal enters the fourth wavelength division multiplexer, and the residual pump light enters the sixth wavelength division multiplexer;
the fourth wavelength division multiplexer is respectively connected with the second wavelength division multiplexer, the third wavelength division multiplexer and the fifth wavelength division multiplexer, and is used for transmitting the amplified first wavelength band optical signal output by the third wavelength division multiplexer to the fifth wavelength division multiplexer and inputting the pump light output by an external pump unit transmitted by the fifth wavelength division multiplexer to the second wavelength division multiplexer;
the fifth wavelength division multiplexer is respectively connected with the fourth wavelength division multiplexer and the sixth wavelength division multiplexer, and is used for multiplexing and outputting the amplified first wavelength band optical signal output by the fourth wavelength division multiplexer and the amplified second wavelength band optical signal output by the sixth wavelength division multiplexer, and is also used for inputting the pumping light input by the external pumping unit to the fourth wavelength division multiplexer;
and the sixth wavelength division multiplexer is respectively connected with the second erbium-doped optical fiber, the third wavelength division multiplexer and the fifth wavelength division multiplexer, and is used for inputting the residual pump light output by the first erbium-doped optical fiber to the second erbium-doped optical fiber and transmitting the second band optical signal amplified by the second erbium-doped optical fiber to the fifth wavelength division multiplexer.
Furthermore, a wavelength combining port of the first wavelength division multiplexer is used for being connected with the first transmission optical fiber, a first wavelength division port of the first wavelength division multiplexer is connected with a first wavelength division port of the second wavelength division multiplexer, and a second wavelength division port of the first wavelength division multiplexer is connected with an input end of the second erbium-doped optical fiber;
a first wavelength division port of the second wavelength division multiplexer is connected with a first wavelength division port of the first wavelength division multiplexer, a second wavelength division port of the second wavelength division multiplexer is connected with a second wavelength division port of the fourth wavelength division multiplexer, and a wavelength combination port of the second wavelength division multiplexer is connected with the input end of the first erbium-doped optical fiber;
a wave combination port of the third wavelength division multiplexer is connected with the output end of the first erbium-doped fiber, a first wave division port of the third wavelength division multiplexer is connected with a first wave division port of the fourth wavelength division multiplexer, and a second wave division port of the third wavelength division multiplexer is connected with a second wave division port of the sixth wavelength division multiplexer;
a first wavelength division port of the fourth wavelength division multiplexer is connected with a first wavelength division port of the third wavelength division multiplexer, a second wavelength division port of the fourth wavelength division multiplexer is connected with a second wavelength division port of the second wavelength division multiplexer, and a wavelength combination port of the fourth wavelength division multiplexer is connected with a first wavelength combination port of the fifth wavelength division multiplexer;
a first multiplexing port of the fifth wavelength division multiplexer is connected with a multiplexing port of the fourth wavelength division multiplexer, a second multiplexing port of the fifth wavelength division multiplexer is used for being connected with a second transmission optical fiber, and a wavelength division port of the fifth wavelength division multiplexer is connected with a first wavelength division port of the sixth wavelength division multiplexer;
and a first wavelength division port of the sixth wavelength division multiplexer is connected with a wavelength division port of the fifth wavelength division multiplexer, a wave combination port of the sixth wavelength division multiplexer is connected with the output end of the second erbium-doped optical fiber, and a second wavelength division port of the sixth wavelength division multiplexer is connected with a second wavelength division port of the third wavelength division multiplexer.
Further, the passive optical amplifying unit further includes: first isolator, second isolator, third isolator, fourth isolator, wherein:
the input end of the first isolator is connected with a first wavelength division port of the first wavelength division multiplexer, and the output end of the first isolator is connected with a first wavelength division port of the second wavelength division multiplexer;
the input end of the second isolator is connected with the first wavelength division port of the third wavelength division multiplexer, and the output end of the second isolator is connected with the first wavelength division port of the fourth wavelength division multiplexer;
the input end of the third isolator is connected with the second wavelength division port of the first wavelength division multiplexer, and the output end of the third isolator is connected with the input end of the second erbium-doped fiber;
and the input end of the fourth isolator is connected with the first wavelength division port of the sixth wavelength division multiplexer, and the output end of the fourth isolator is connected with the wavelength division port of the fifth wavelength division multiplexer.
Furthermore, the first erbium-doped fiber is a C-band erbium-doped fiber, and the second erbium-doped fiber is an L-band erbium-doped fiber.
Further, the first erbium-doped fiber is a C-band erbium-doped fiber, the 1550nm wavelength peak absorption value of the first erbium-doped fiber is 5.5dB/m, the numerical aperture of the first erbium-doped fiber is 0.32, the second erbium-doped fiber is an L-band erbium-doped fiber, the 1530nm wavelength peak absorption value of the second erbium-doped fiber is 18dB/m, and the numerical aperture of the second erbium-doped fiber is 0.25.
On the other hand, the invention also discloses a multiband ultra-long span transmission system, which comprises the passive optical amplification unit, a transmitting unit, a first transmission optical fiber, a second transmission optical fiber, a pumping unit and a receiving unit, wherein:
the output end of the transmitting unit is connected with a first transmission optical fiber and used for transmitting two wave band optical signals to a first wavelength division multiplexer of the passive optical amplification unit through the first transmission optical fiber;
a first wavelength division multiplexer of the passive optical amplification unit is connected with the first transmission optical fiber, and a fifth wavelength division multiplexer of the passive optical amplification unit is connected with the pumping unit through the second transmission optical fiber;
and one end of the pumping unit is connected with the second transmission optical fiber, the other end of the pumping unit is connected with the receiving unit, and the fifth wavelength division multiplexer is used for inputting the pumping light to the passive optical amplification unit through the second transmission optical fiber.
Based on the technical scheme, compared with the prior art, the invention has the beneficial effects that:
the passive optical amplifying unit of the present application includes: the optical fiber coupling device comprises a first wavelength division multiplexer, a second wavelength division multiplexer, a third wavelength division multiplexer, a fourth wavelength division multiplexer, a fifth wavelength division multiplexer, a sixth wavelength division multiplexer, a first erbium-doped optical fiber and a second erbium-doped optical fiber, wherein a wave combining port of the first wavelength division multiplexer is connected with an external first transmission optical fiber, and a fifth wavelength division multiplexer of a passive optical amplification unit is connected with an external pumping unit through the second transmission optical fiber. The passive optical amplification unit allows optical signals of two wave bands to be input simultaneously, the optical signals of a first wave band are transmitted by a first wavelength division multiplexer, a second wavelength division multiplexer, a first erbium-doped optical fiber, a third wavelength division multiplexer, a fourth wavelength division multiplexer and a fifth wavelength division multiplexer, pump light output by the pump unit enters from the input end of the first erbium-doped optical fiber in the positive direction, and the optical signals of the first wave band are amplified after passing through the first erbium-doped optical fiber; the second band optical signal is transmitted by the first wavelength division multiplexer, the second erbium-doped optical fiber, the sixth wavelength division multiplexer and the fifth wavelength division multiplexer, pump light output by the pumping unit reversely enters from the output end of the second erbium-doped optical fiber through residual pump light output by the first erbium-doped optical fiber and the third wavelength division multiplexer, and the second band optical signal is amplified after passing through the second erbium-doped optical fiber. This application passive optical amplification unit is ingenious to be combined a plurality of passive devices, only occupies a circuit fibre core and just can realize the transmission of two way light signal simultaneously, and pump light does not additionally occupy the fibre core simultaneously, can effectively prolong overlength span optical fiber communication system's transmission distance, reduces the circuit and lays the cost, and the stability of performance is good, and is longe-lived.
Drawings
Fig. 1 is a schematic structural diagram of a passive optical amplifying unit according to an embodiment of the present invention;
fig. 2 is a schematic diagram of a transmission flow of an optical signal in a first wavelength band in a passive optical amplifying unit according to an embodiment of the present invention;
fig. 3 is a schematic diagram illustrating a transmission flow of optical signals in a second wavelength band in a passive optical amplifying unit according to an embodiment of the present invention;
fig. 4 is a schematic diagram of the transmission flow of the pump light in the passive optical amplifying unit according to the embodiment of the present invention;
fig. 5 is a schematic structural diagram of another passive optical amplifying unit according to an embodiment of the present invention;
fig. 6 is a schematic structural diagram of a multiband ultra-long span transmission system according to an embodiment of the present invention.
Detailed Description
Some brief descriptions will be made to the technical principles involved in the embodiments of the present invention.
The remote pump amplification technology is characterized in that a passive optical amplification unit consisting of a passive gain medium Erbium-Doped Fiber (EDF) and a related passive device is introduced into a system transmission link, and a pump source for providing pump amplification is placed at a receiving end of the transmission system. The signal light is amplified in the erbium-doped fiber, so that the output optical power of the transmission fiber is obviously improved. And because the passive optical amplification unit is a passive device, no power supply facility or personnel maintenance is needed at the point, the passive optical amplification unit is suitable for crossing the desert, the plateau, the lake, the strait and other areas which are inconvenient to maintain and supply power, and the daily maintenance cost is reduced. The amplification principle of the erbium-doped fiber is as follows: the energy difference between the metastable state and the ground state of the rare-earth element Er (3+) doped in the optical fiber is equivalent to the energy of 1550nm photons. When pump light energy of appropriate wavelength (980nm or 1480nm) is absorbed, electrons will transition from the ground state to an excited state of higher energy order. Then a small amount of energy is released to transfer to a stable metastable state, and the electrons of the erbium ions are subjected to a huge inversion when the pumping light source is sufficient. I.e., the metastable state of the high energy order is more abundant than the lower baseband electrons of the low energy order. When a proper optical signal passes through, the metastable electrons can generate stimulated emission effect and emit a large number of photons with the same wavelength.
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
As shown in fig. 1, a passive optical amplifying unit includes: a first wavelength division multiplexer WDM1, a second wavelength division multiplexer WDM2, a third wavelength division multiplexer WDM3, a fourth wavelength division multiplexer WDM4, a fifth wavelength division multiplexer WDM5, a sixth wavelength division multiplexer WDM6, a first erbium doped fiber, and a second erbium doped fiber, wherein:
the input end of the first wavelength division multiplexer WDM1 is used for connecting with the first transmission optical fiber, the output end is respectively connected with the second wavelength division multiplexer WDM2 and the second erbium-doped optical fiber, and the first wavelength division multiplexer WDM1 is used for separating the optical signals of two wave bands input from the outside into optical signals of a first wave band and optical signals of a second wave band, wherein the optical signals of the first wave band enter the second wavelength division multiplexer, and the optical signals of the second wave band enter the second erbium-doped optical fiber. The first transmission fibre is not shown IN figure 1 and its connection point to the first wavelength division multiplexer WDM1 is denoted by IN.
In detail, as shown in fig. 6, the wavelength multiplexing port 1a of the first wavelength division multiplexer WDM1 is configured to be connected to a first transmission optical fiber, the first wavelength division port 1b of the first wavelength division multiplexer WDM1 is connected to the first wavelength division port 3a of the second wavelength division multiplexer WDM2, and the second wavelength division port 1c of the first wavelength division multiplexer WDM1 is connected to the input end 10a of the second erbium-doped optical fiber. That is, the wavelength multiplexing port 1a of the first wavelength division multiplexer WDM1 is a wavelength multiplexing port for the first wavelength band optical signal and the second wavelength band optical signal, the first wavelength multiplexing port 1b is used for transmitting the first wavelength band optical signal, the second wavelength multiplexing port 1c is used for transmitting the second wavelength band optical signal, and the first wavelength division multiplexer WDM1 mainly realizes the separation of the two wavelength band optical signals.
The second wavelength division multiplexer WDM2 is connected to the first wavelength division multiplexer WDM1, the fourth wavelength division multiplexer WDM4 and the first erbium-doped fiber respectively, and is configured to combine the first wavelength band optical signal output by the first wavelength division multiplexer WDM1 and the pump light output by the fifth wavelength division multiplexer WDM5 and transmitted by the fourth wavelength division multiplexer WDM4 and input the combined wave to the first erbium-doped fiber, so as to achieve amplification of the first wavelength band optical signal.
Specifically, a first wavelength division port 3a of the second wavelength division multiplexer WDM2 is connected to a first wavelength division port 1b of the first wavelength division multiplexer WDM1, a second wavelength division port 3b of the second wavelength division multiplexer WDM2 is connected to a second wavelength division port 7b of the fourth wavelength division multiplexer WDM4, and a wavelength combination port 3c of the second wavelength division multiplexer WDM2 is connected to an input end 3a of the first erbium-doped optical fiber. That is, the first wavelength division port 3a of the second wavelength division multiplexer WDM2 is used for feeding the first band optical signal, the second wavelength division port 3b is used for feeding the pump light, and the wavelength combining port 3c performs wavelength combining of the first band optical signal and the pump light. The second wavelength division multiplexer WDM2 mainly realizes the wave combination of the first band optical signal and the pump optical signal, and makes the first band optical signal realize the signal amplification in the first erbium-doped fiber.
The third wavelength division multiplexer WDM3 is connected to the first erbium-doped fiber, the fourth wavelength division multiplexer WDM4 and the sixth wavelength division multiplexer WDM6 respectively, and is configured to separate the amplified first wavelength band optical signal output by the first erbium-doped fiber from the residual pump light output by the first erbium-doped fiber, where the amplified first wavelength band optical signal enters the fourth wavelength division multiplexer WDM4, and the residual pump light enters the sixth wavelength division multiplexer WDM 6.
Specifically, the wavelength combining port 5a of the third wavelength division multiplexer WDM3 is connected to the output end 3c of the first erbium-doped fiber, the first wavelength division port 5b of the third wavelength division multiplexer WDM3 is connected to the first wavelength division port 7a of the fourth wavelength division multiplexer WDM4, and the second wavelength division port 5c of the third wavelength division multiplexer WDM3 is connected to the second wavelength division port 11a of the sixth wavelength division multiplexer WDM 6. That is, the wavelength multiplexing port 5a of the third wavelength division multiplexer WDM3 multiplexes the first band optical signal and the pump light, the first wavelength multiplexing port 5b transmits the first band optical signal, and the second wavelength multiplexing port 5c transmits the pump light. The third wavelength division multiplexer WDM3 mainly achieves the separation of the first band optical signal and the pump light. The first band optical signal has been amplified and continues forward, and the residual pump light is input into the second erbium-doped fiber through the sixth wavelength division multiplexer WDM 6.
The fourth wavelength division multiplexer WDM4 is respectively connected to the second wavelength division multiplexer WDM2, the third wavelength division multiplexer WDM3 and the fifth wavelength division multiplexer WDM5, and is configured to transmit the amplified first wavelength band optical signal output by the third wavelength division multiplexer WDM3 to the fifth wavelength division multiplexer WDM5, and input the pump light output by the external pump unit transmitted by the fifth wavelength division multiplexer WDM5 to the second wavelength division multiplexer WDM 2.
Specifically, the first wavelength division port 7a of the fourth wavelength division multiplexer WDM4 is connected to the first wavelength division port 5b of the third wavelength division multiplexer WDM3, the second wavelength division port 7b of the fourth wavelength division multiplexer WDM4 is connected to the second wavelength division port 3b of the second wavelength division multiplexer WDM2, and the wavelength combination port 7c of the fourth wavelength division multiplexer WDM4 is connected to the first wavelength combination port 8a of the fifth wavelength division multiplexer WDM 5. That is, the first wavelength division port 7a of the fourth wavelength division multiplexer WDM4 receives the first wavelength band optical signal, the second wavelength division port 7b receives the pump light, and the wavelength combining port 7c is a wavelength combining port of the first wavelength band optical signal and the pump light. The fourth wavelength division multiplexer WDM4 mainly realizes the separation of the amplified first wavelength band optical signal and the pump light, the amplified first wavelength band optical signal goes forward, the pump light enters the second wavelength division multiplexer WDM2 from the fourth wavelength division multiplexer WDM4, and the forward amplification of the first wavelength band optical signal is realized.
The fifth wavelength division multiplexer WDM5 is connected to the fourth wavelength division multiplexer WDM4 and the sixth wavelength division multiplexer WDM6 respectively, and is configured to multiplex and output the amplified first wavelength band optical signal output by the fourth wavelength division multiplexer WDM4 and the amplified second wavelength band optical signal output by the sixth wavelength division multiplexer WDM6, and further configured to input the pump light input by the external pump unit to the fourth wavelength division multiplexer WDM 4. In which fig. 1 does not show external pump units, the connection point of the fifth wavelength division multiplexer WDM5 with a pump unit is denoted by OUT.
Specifically, a first add port 8a of the fifth wavelength division multiplexer WDM5 is connected to a add port 7c of the fourth wavelength division multiplexer WDM4, a second add port 8b of the fifth wavelength division multiplexer WDM5 is used for connecting to the second transmission fiber, and a drop port 8c of the fifth wavelength division multiplexer WDM5 is connected to a first drop port 11c of the sixth wavelength division multiplexer WDM 6. That is, the first multiplexing port 8a of the fifth wavelength division multiplexer WDM5 is a multiplexing port of the first band optical signal and the pump light, the second multiplexing port 8b is a multiplexing port of the first band optical signal, the second band optical signal and the pump light, and the demultiplexing port 8c routes the second band optical signal. The fifth wavelength division multiplexer WDM5 mainly realizes the multiplexing of the first band of wavelengths and the second band of wavelengths.
And the sixth wavelength division multiplexer WDM6 is respectively connected with the second erbium-doped fiber, the third wavelength division multiplexer WDM3 and the fifth wavelength division multiplexer WDM5, and is used for inputting the residual pump light output by the first erbium-doped fiber to the second erbium-doped fiber and transmitting the second band optical signal amplified by the second erbium-doped fiber to the fifth wavelength division multiplexer WDM 5.
Specifically, the first wavelength division port 11c of the sixth wavelength division multiplexer WDM6 is connected to the wavelength division port 8c of the fifth wavelength division multiplexer WDM5, the wavelength combination port 11b of the sixth wavelength division multiplexer WDM6 is connected to the output end 10b of the second erbium-doped fiber, and the second wavelength division port 11a of the sixth wavelength division multiplexer WDM6 is connected to the second wavelength division port 5c of the third wavelength division multiplexer WDM 3. That is, the first wavelength division port 11c of the sixth wavelength division multiplexer WDM6 receives the second band optical signal, the second wavelength division port 11a receives the pump light, and the multiplexing port 11b is a multiplexing port of the second band optical signal and the pump light. The sixth wavelength division multiplexer WDM6 mainly combines the second band optical signal with the residual pump light output through the first erbium-doped fiber.
For convenience of understanding the embodiments of the present invention, the transmission flow direction of optical signals in two wavelength bands and the transmission flow direction of pump light after the optical signals in two wavelength bands are simultaneously input to the passive optical amplification unit will be described with reference to fig. 2 to 4.
Specifically, as shown in fig. 2, the transmission flow direction of the first band optical signal is:
(1) a first wavelength division multiplexer WDM 1- (2) a second wavelength division multiplexer WDM 2- (3) a first band erbium-doped fiber- (4) a third wavelength division multiplexer WDM 3- (5) a fourth wavelength division multiplexer WDM 4- (6) a fifth wavelength division multiplexer WDM 5.
As shown in fig. 3, the transmission flow direction of the second band optical signal is:
(1) the first wavelength division multiplexer WDM 1- (2) the second band erbium doped fiber- (3) the sixth wavelength division multiplexer WDM 6- (4) and the fifth wavelength division multiplexer WDM 5.
As shown in fig. 4, the transmission flow direction of the pump light input by the external pump unit is:
(1) a fifth wavelength division multiplexer WDM 5- (2), a fourth wavelength division multiplexer WDM 4- (3), a second wavelength division multiplexer WDM 2- (4), a first wavelength band erbium-doped fiber- (5), a third wavelength division multiplexer WDM 3- (6), a sixth wavelength division multiplexer WDM 6- (7), a second wavelength band erbium-doped fiber.
In the embodiment, optical signals of two wave bands are simultaneously input to a passive optical amplification unit, a first wave band optical signal is transmitted by a first wavelength division multiplexer, a second wavelength division multiplexer, a first erbium-doped optical fiber, a third wavelength division multiplexer, a fourth wavelength division multiplexer and a fifth wavelength division multiplexer, pump light output by a pump unit enters from the input end of the first erbium-doped optical fiber in the positive direction, and the first wave band optical signal realizes signal amplification after passing through the first erbium-doped optical fiber; the second band optical signal is transmitted by the first wavelength division multiplexer, the second erbium-doped optical fiber, the sixth wavelength division multiplexer and the fifth wavelength division multiplexer, pump light output by the pumping unit reversely enters from the output end of the second erbium-doped optical fiber through residual pump light output by the first erbium-doped optical fiber and the third wavelength division multiplexer, and the second band optical signal is amplified after passing through the second erbium-doped optical fiber. The passive optical amplification unit of this application combines a plurality of passive devices, only occupies the transmission that a circuit fibre core just can realize two way light signal simultaneously, and pump light does not additionally occupy the fibre core simultaneously, can effectively prolong overlength span optical fiber communication system's transmission distance, reduces the circuit and lays the cost, and the stability of performance is good, and is longe-lived.
Preferably, the optical isolator is a passive optical device which is realized based on Faraday rotation non-reciprocity and only allows one-way light to pass through, has the characteristics of high isolation and low insertion loss, and can improve the light wave transmission efficiency. Therefore, as shown in fig. 5, in some embodiments, the passive optical amplifying unit further includes: a first isolator ISO1, a second isolator ISO2, a third isolator ISO3, a fourth isolator ISO4, wherein:
the input end 2a of the first isolator ISO1 is connected with the first wavelength division port 1b of the first wavelength division multiplexer, and the output end 2b of the first isolator ISO1 is connected with the first wavelength division port 3a of the second wavelength division multiplexer.
An input end 6a of the second isolator ISO2 is connected with a first wavelength division port 5b of the third wavelength division multiplexer, and an output end 6b of the second isolator ISO2 is connected with a first wavelength division port 7a of the fourth wavelength division multiplexer.
The input end 9a of the third isolator ISO3 is connected with the second wavelength division port 1c of the first wavelength division multiplexer, and the output end 9b of the third isolator ISO3 is connected with the input end of the second erbium-doped fiber.
An input end 12a of the fourth isolator ISO4 is connected to the first wavelength division port 11c of the sixth wavelength division multiplexer, and an output end 12b of the fourth isolator ISO4 is connected to the wavelength division port 8c of the fifth wavelength division multiplexer.
It is understood that in some embodiments, the first and second band optical signals may be C-band optical signals (having wavelengths in the range of 1528nm to 1568nm) or L-band optical signals (1570nm to 1612nm), or both of them may be selected as desired. However, through a lot of experiments, the applicant finds that if the input two band optical signals are C-band optical signals and L-band optical signals, the first band optical signal is preferably a C-band optical signal, and the second band optical signal is preferably an L-band optical signal. Specifically, the method comprises the following steps:
table 1 shows experimental data (the wavelength range of externally input pump light is 1450nm to 1500nm) when the first band optical signal is a C-band optical signal and the second band optical signal is an L-band optical signal, that is, a scheme of forward pumping the C-band optical signal and backward pumping the L-band optical signal with the residual pump light output by the first erbium-doped fiber is adopted. The experimental results show that: under the condition that the gain of the C-band optical signal is 20dB, the output residual pump light is still larger, and when the output residual pump light is more than 20mw, the L-band optical signal has the signal optical gain of 20 dB.
TABLE 1
Table 2 shows experimental data (the wavelength range of externally input pump light is 1450nm to 1500nm) when the first band optical signal is an L-band optical signal and the second band optical signal is a C-band optical signal, that is, a scheme of forward pumping the L-band optical signal and backward pumping the C-band optical signal with the residual pump light output by the first erbium-doped fiber is adopted. The experimental results show that: under the condition that the gain of the L-band optical signal is 20dB, the output residual pump light is very small and is not enough for the C-band signal to be used for optical amplification (the pump light required by the C-band optical amplification needs at least 5 mw). Therefore, the first wavelength band optical signal is preferably a C-band optical signal and the second wavelength band optical signal is preferably an L-band optical signal.
TABLE 2
| L-band forward pumping power/mw | Residual pump power/mw output to the C- |
| 20 | 0.00001 |
| 30 | 0.0003 |
| 40 | 0.0027 |
| 50 | 0.0042 |
| 60 | 0.0058 |
| 70 | 0.0076 |
| 80 | 0.0095 |
| 90 | 0.011 |
Preferably, when the first-band optical signal is a C-band optical signal and the second-band optical signal is an L-band optical signal, the first erbium-doped fiber can be obtained through a large number of experiments as a C-band erbium-doped fiber, and has a peak absorption value of 5.5dB/m at a wavelength of 1550nm and a numerical aperture of 0.32; the second erbium-doped fiber is an L-band erbium-doped fiber, and the performance of the signal light output by the passive optical amplification unit is optimal when the peak absorption value of the second erbium-doped fiber at the wavelength of 1530nm is 18dB/m and the numerical aperture is 0.25.
In another aspect, an embodiment of the present invention further discloses a multiband ultra-long span transmission system, as shown in fig. 6, the multiband ultra-long span transmission system includes the passive optical amplification unit 10 of the above embodiment, and a transmitting unit 20, a first transmission optical fiber 30, a second transmission optical fiber 40, a pumping unit 50, and a receiving unit 60, where:
the output end of the transmitting unit 20 is connected to a first transmission optical fiber 30, and is used for transmitting two wavelength band optical signals to a first wavelength division multiplexer of the passive optical amplifying unit 10 through the first transmission optical fiber 30.
A first wavelength division multiplexer of the passive optical amplification unit 10 is connected to the first transmission optical fiber 30, and a fifth wavelength division multiplexer of the passive optical amplification unit 10 is connected to the pumping unit 50 through the second transmission optical fiber 40.
One end of the pumping unit 50 is connected to the second transmission fiber 40, and the other end is connected to the receiving unit 60, and is configured to input the pumping light to a fifth wavelength division multiplexer of the passive optical amplification unit 10 through the second transmission fiber 40.
The passive optical amplifying unit 10 includes: the optical fiber pump comprises a first wavelength division multiplexer WDM1, a second wavelength division multiplexer WDM2, a third wavelength division multiplexer WDM3, a fourth wavelength division multiplexer WDM4, a fifth wavelength division multiplexer WDM5, a sixth wavelength division multiplexer WDM6, a first erbium-doped fiber and a second erbium-doped fiber, wherein a wave combining port of the first wavelength division multiplexer WDM1 is connected with a first transmission fiber, and the fifth wavelength division multiplexer WDM5 is connected with a pumping unit 50 through a second transmission fiber 40; the output end of the transmitting unit 20 is connected to the first transmission optical fiber 30, and is used for transmitting the two wavelength band optical signals to the first wavelength division multiplexer WDM1 of the passive optical amplification unit 10 through the first transmission optical fiber 30; the pumping unit 50 has one end connected to the second transmission fiber 40 and the other end connected to the receiving unit 60, and is configured to input the pumping light to a fifth wavelength division multiplexer WDM5 of the passive optical amplification unit 10 through the second transmission fiber 40.
Wherein the length l (km) of the second transmission fiber 40 should satisfy the following condition:
wherein Pppm is the pump light power (unit: dBm) outputted by the pump unit 50, PRGUThe pump light power (unit: dBm) received by the passive optical amplification unit 10, and α is the loss factor (unit: dB/km) of the pump light.
In addition, the applicant finds out through a large number of experiments that when the first waveband optical signal is an L waveband optical signal, the second waveband optical signal is a C waveband optical signal, and the wavelength range of the pump light is 1450 nm-1500 nm, the signal transmission effect of the multiband ultra-long span transmission system is the best. For specific experimental contents, reference may be made to the foregoing embodiments, which are not described herein again.
The multiband ultra-long span transmission system inputs optical signals of two wavebands into a passive optical amplification unit simultaneously, the optical signals of a first waveband are transmitted by a first wavelength division multiplexer, a second wavelength division multiplexer, a first erbium-doped optical fiber, a third wavelength division multiplexer, a fourth wavelength division multiplexer and a fifth wavelength division multiplexer, pumping light output by a pumping unit enters from the input end of the first erbium-doped optical fiber in the positive direction, and the optical signals of the first waveband are amplified after passing through the first erbium-doped optical fiber; the second band optical signal is transmitted by the first wavelength division multiplexer, the second erbium-doped optical fiber, the sixth wavelength division multiplexer and the fifth wavelength division multiplexer, pump light output by the pumping unit reversely enters from the output end of the second erbium-doped optical fiber through residual pump light output by the first erbium-doped optical fiber and the third wavelength division multiplexer, and the second band optical signal is amplified after passing through the second erbium-doped optical fiber. This application multiband overlength span transmission system is ingenious to be combined a plurality of passive devices, only occupies the transmission that a circuit fibre core just can realize two way optical signal simultaneously, and the pump light does not additionally occupy the fibre core simultaneously, can effectively prolong overlength span optical fiber communication system's transmission distance, reduces the circuit and lays the cost, and the stability of performance is good, and is longe-lived.
In the foregoing detailed description, various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments of the subject matter require more features than are expressly recited in each claim. Rather, as the following claims reflect, invention lies in less than all features of a single disclosed embodiment. Thus, the following claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.
What has been described above includes examples of one or more embodiments. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the aforementioned embodiments, but one of ordinary skill in the art may recognize that many further combinations and permutations of various embodiments are possible. Accordingly, the embodiments described herein are intended to embrace all such alterations, modifications and variations that fall within the scope of the appended claims. Furthermore, to the extent that the term "includes" is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term "comprising" as "comprising" is interpreted when employed as a transitional word in a claim. Furthermore, any use of the term "or" in the specification of the claims is intended to mean a "non-exclusive or".
Claims (8)
1. A passive optical amplification unit, comprising: first wavelength division multiplexer, second wavelength division multiplexer, third wavelength division multiplexer, fourth wavelength division multiplexer, fifth wavelength division multiplexer, sixth wavelength division multiplexer, first erbium-doped optical fiber and second erbium-doped optical fiber, wherein:
the input end of the first wavelength division multiplexer is used for being connected with an external first transmission optical fiber, the output end of the first wavelength division multiplexer is respectively connected with the second wavelength division multiplexer and the second erbium-doped optical fiber, and the first wavelength division multiplexer is used for separating optical signals of two externally input wave bands into optical signals of a first wave band and optical signals of a second wave band, wherein the optical signals of the first wave band enter the second wavelength division multiplexer, and the optical signals of the second wave band enter the second erbium-doped optical fiber;
the second wavelength division multiplexer is respectively connected with the first wavelength division multiplexer, the fourth wavelength division multiplexer and the first erbium-doped optical fiber and is used for inputting a first wavelength band optical signal output by the first wavelength division multiplexer and pump light wave output by the fifth wavelength division multiplexer and transmitted by the fourth wavelength division multiplexer into the first erbium-doped optical fiber so as to realize amplification of the first wavelength band optical signal;
the third wavelength division multiplexer is respectively connected with the first erbium-doped optical fiber, the fourth wavelength division multiplexer and the sixth wavelength division multiplexer and is used for separating the amplified first wavelength band optical signal output by the first erbium-doped optical fiber and the residual pump light output by the first erbium-doped optical fiber, the amplified first wavelength band optical signal enters the fourth wavelength division multiplexer, and the residual pump light enters the sixth wavelength division multiplexer;
the fourth wavelength division multiplexer is respectively connected with the second wavelength division multiplexer, the third wavelength division multiplexer and the fifth wavelength division multiplexer, and is used for transmitting the amplified first wavelength band optical signal output by the third wavelength division multiplexer to the fifth wavelength division multiplexer and inputting the pump light output by an external pump unit transmitted by the fifth wavelength division multiplexer to the second wavelength division multiplexer;
the fifth wavelength division multiplexer is respectively connected with the fourth wavelength division multiplexer and the sixth wavelength division multiplexer, and is used for multiplexing and outputting the amplified first wavelength band optical signal output by the fourth wavelength division multiplexer and the amplified second wavelength band optical signal output by the sixth wavelength division multiplexer, and is also used for inputting the pumping light input by the external pumping unit to the fourth wavelength division multiplexer;
and the sixth wavelength division multiplexer is respectively connected with the second erbium-doped optical fiber, the third wavelength division multiplexer and the fifth wavelength division multiplexer, and is used for inputting the residual pump light output by the first erbium-doped optical fiber to the second erbium-doped optical fiber and transmitting the second band optical signal amplified by the second erbium-doped optical fiber to the fifth wavelength division multiplexer.
2. The passive optical amplification unit of claim 1, wherein the multiplexing port of the first wavelength division multiplexer is configured to be connected to a first transmission optical fiber, the first wavelength division port of the first wavelength division multiplexer is connected to the first wavelength division port of the second wavelength division multiplexer, and the second wavelength division port of the first wavelength division multiplexer is connected to an input end of a second erbium-doped optical fiber;
a first wavelength division port of the second wavelength division multiplexer is connected with a first wavelength division port of the first wavelength division multiplexer, a second wavelength division port of the second wavelength division multiplexer is connected with a second wavelength division port of the fourth wavelength division multiplexer, and a wavelength combination port of the second wavelength division multiplexer is connected with the input end of the first erbium-doped optical fiber;
a wave combination port of the third wavelength division multiplexer is connected with the output end of the first erbium-doped fiber, a first wave division port of the third wavelength division multiplexer is connected with a first wave division port of the fourth wavelength division multiplexer, and a second wave division port of the third wavelength division multiplexer is connected with a second wave division port of the sixth wavelength division multiplexer;
a first wavelength division port of the fourth wavelength division multiplexer is connected with a first wavelength division port of the third wavelength division multiplexer, a second wavelength division port of the fourth wavelength division multiplexer is connected with a second wavelength division port of the second wavelength division multiplexer, and a wavelength combination port of the fourth wavelength division multiplexer is connected with a first wavelength combination port of the fifth wavelength division multiplexer;
a first multiplexing port of the fifth wavelength division multiplexer is connected with a multiplexing port of the fourth wavelength division multiplexer, a second multiplexing port of the fifth wavelength division multiplexer is used for being connected with a second transmission optical fiber, and a wavelength division port of the fifth wavelength division multiplexer is connected with a first wavelength division port of the sixth wavelength division multiplexer;
and a first wavelength division port of the sixth wavelength division multiplexer is connected with a wavelength division port of the fifth wavelength division multiplexer, a wave combination port of the sixth wavelength division multiplexer is connected with the output end of the second erbium-doped optical fiber, and a second wavelength division port of the sixth wavelength division multiplexer is connected with a second wavelength division port of the third wavelength division multiplexer.
3. The passive optical amplification unit of claim 2, further comprising: first isolator, second isolator, third isolator, fourth isolator, wherein:
the input end of the first isolator is connected with a first wavelength division port of the first wavelength division multiplexer, and the output end of the first isolator is connected with a first wavelength division port of the second wavelength division multiplexer;
the input end of the second isolator is connected with the first wavelength division port of the third wavelength division multiplexer, and the output end of the second isolator is connected with the first wavelength division port of the fourth wavelength division multiplexer;
the input end of the third isolator is connected with the second wavelength division port of the first wavelength division multiplexer, and the output end of the third isolator is connected with the input end of the second erbium-doped fiber;
and the input end of the fourth isolator is connected with the first wavelength division port of the sixth wavelength division multiplexer, and the output end of the fourth isolator is connected with the wavelength division port of the fifth wavelength division multiplexer.
4. A passive optical amplification unit according to any one of claims 1 to 3, wherein the first erbium-doped fiber is a C-band erbium-doped fiber and the second erbium-doped fiber is an L-band erbium-doped fiber.
5. The passive optical amplifying unit according to claim 4, wherein the first erbium-doped fiber has a peak absorption value of 5.5dB/m at a wavelength of 1550nm and a numerical aperture of 0.32, and the second erbium-doped fiber has a peak absorption value of 18dB/m at a wavelength of 1530nm and a numerical aperture of 0.25.
6. A multiband ultra-long span transmission system comprising the passive optical amplification unit according to any one of claims 1 to 5, further comprising: emission unit, first transmission fiber, second transmission fiber, pumping unit and receiving unit, wherein:
the output end of the transmitting unit is connected with a first transmission optical fiber and used for transmitting two wave band optical signals to a first wavelength division multiplexer of the passive optical amplification unit through the first transmission optical fiber;
a first wavelength division multiplexer of the passive optical amplification unit is connected with the first transmission optical fiber, and a fifth wavelength division multiplexer of the passive optical amplification unit is connected with the pumping unit through the second transmission optical fiber;
and one end of the pumping unit is connected with the second transmission optical fiber, the other end of the pumping unit is connected with the receiving unit, and the fifth wavelength division multiplexer is used for inputting the pumping light to the passive optical amplification unit through the second transmission optical fiber.
7. The multiband ultra-long span transmission system of claim 1, wherein the length, l (km), of the second transmission fiber is:
wherein Pppm is the pump light power (unit: dBm) output by the pump unit, PRGUThe power (unit: dBm) of the pump light received by the passive optical amplification unit, and alpha is the loss coefficient (unit: dB/km) of the pump light.
8. The multiband transmission system of claim 1, wherein the pump units have a pump light wavelength ranging from 1450nm to 1500 nm.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104319611A (en) * | 2014-11-19 | 2015-01-28 | 天津光电通信技术有限公司 | Low-noise remote pump EDFA |
| CN105071857A (en) * | 2015-06-30 | 2015-11-18 | 武汉光迅科技股份有限公司 | Cascading multi-span on-tower relay light transmission system |
| CN109728854A (en) * | 2018-11-20 | 2019-05-07 | 武汉光迅科技股份有限公司 | To remote gain unit and remote optical pumping amplifier before a kind of |
| CN112953640A (en) * | 2021-01-18 | 2021-06-11 | 中国南方电网有限责任公司超高压输电公司 | Cascade remote pump amplification system, remote gain unit and signal light amplification method |
-
2021
- 2021-10-25 CN CN202111238697.2A patent/CN113824500A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104319611A (en) * | 2014-11-19 | 2015-01-28 | 天津光电通信技术有限公司 | Low-noise remote pump EDFA |
| CN105071857A (en) * | 2015-06-30 | 2015-11-18 | 武汉光迅科技股份有限公司 | Cascading multi-span on-tower relay light transmission system |
| CN109728854A (en) * | 2018-11-20 | 2019-05-07 | 武汉光迅科技股份有限公司 | To remote gain unit and remote optical pumping amplifier before a kind of |
| CN112953640A (en) * | 2021-01-18 | 2021-06-11 | 中国南方电网有限责任公司超高压输电公司 | Cascade remote pump amplification system, remote gain unit and signal light amplification method |
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