Multichannel polarization multiplexing and wavelength division multiplexing hybrid module

Abstract

The utility model provides a multichannel polarization multiplexing and wavelength division multiplexing hybrid module, which relates to the field of optical fiber communication, and comprises an incident optical fiber collimator and N emergent modules, N is an integer greater than 2, and each emergent module comprises a filter, a birefringent crystal and a dual-optical fiber polarization-maintaining collimator. Compared with the prior art, the hybrid module provided by the utility model is additionally provided with a wavelength division multiplexing function on the basis of pure polarization multiplexing / demultiplexing, so that polarization signals can be loaded with specific wavelength signals, the signals are mutually connected in series through a free space optical path, 2N signals are multiplexed in one optical fiber for N different wavelengths, and the wavelength division multiplexing function is realized. Due to the fact that the 2N signals are different in wavelength and polarization state and cannot be interfered, the 2N signals can be transmitted at the same time through the same optical fiber, more use scenes can be expanded, and state changes of multiple targets can be monitored at the same time under the complex condition.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of optical fiber communication, especially a kind of multi-channel polarization multiplexing and wavelength division multiplexing hybrid module. BACKGROUND

[0002] The polarization multiplexing product scheme existing in the market at present is polarization beam combiner PBC / splitter PBS, and the polarization signal multiplexed / demultiplexed by this scheme cannot carry wavelength information, and can only distinguish 2 polarization state information, so the information carrying the 2 polarization states can be transmitted in 2 states in a fiber, equivalent to that one fiber can only transmit 2 signals, so that the utilization rate of fiber resources and communication resources is not high.The wavelength division multiplexing module of conventional multi-channel (channel number is represented by N) is connected in series using free-space optical path, as shown in Figure 1 As shown in the figure, first take the first channel as an example to explain, the first channel is composed of 1 ordinary single optical fiber collimator 01, 1 optical filter 02, 1 ordinary single optical fiber collimator 10, wherein the optical fiber 11 is an ordinary optical fiber used as a common end, and the optical fiber 101 is an ordinary optical fiber used as an output end.Multiple wavelength signals λ1...λn are input from the optical fiber 11, and then filtered by the optical filter 02, and the wavelength λ1 can be transmitted and the wavelengths λ2...λn can be reflected.The transmitted wavelength signal λ1 is focused by the single optical fiber collimator 10 to the optical fiber 101 for reception and transmission.The second channel is composed of 1 optical filter 04 and 1 ordinary single optical fiber collimator 20, and the optical fiber 201 is an ordinary optical fiber used as an output end, and the signal is input from the single fiber collimator 01 and obtained after being reflected by the optical filter 02, and then filtered by the optical filter 04, and the wavelength signal λ2 can be transmitted and the wavelengths λ3...λn can be reflected.The transmitted wavelength λ2 is focused by the single optical fiber collimator 20 to the optical fiber 201 for reception and transmission.By analogy, the filtering or loading output of multiple channels N wavelengths is completed.

[0003] From the above optical transmission process, it can be seen that a single polarization device PBC / PBS can only transmit 2 polarization states, and a conventional multi-channel wavelength division multiplexing device or module can only transmit N wavelengths without superimposing polarization states, both of which are single transmission modes, and the communication capacity of the optical fiber is not more effectively utilized. UTILITY MODEL CONTENTS

[0004] In view of the above problems, the utility model provides a kind of multi-channel polarization multiplexing and wavelength division multiplexing hybrid module, which increases the wavelength division multiplexing function on the basis of pure polarization multiplexing / demultiplexing, so that polarization signal can also load specific wavelength signal, and more use scenarios can be expanded, and in complex conditions, the state change of multiple targets can be monitored simultaneously.

[0005] The technical scheme adopted by the utility model is as follows:

[0006] A multi-channel polarization multiplexing and wavelength division multiplexing hybrid module comprises an incident fiber collimator for an incident optical signal and N exit modules, N being an integer greater than or equal to 2, each exit module comprising a filter for filtering the optical signal, a birefringent crystal for forming two perpendicular polarized lights from the optical signal passing through the filter, and a double fiber polarization maintaining collimator for the two perpendicular polarized lights to pass through; the plurality of exit modules are divided into a first exit module for emitting a first optical signal in use with the incident fiber collimator, a second exit module for receiving the optical signal reflected by the filter in the first exit module and emitting a second optical signal, and an Nth exit module for receiving the optical signal reflected by the filter in an (N-1)th exit module and emitting an Nth optical signal.

[0007] Preferably, the plurality of exit modules are divided into a first column of exit modules and a second column of exit modules, the exit modules in the first and second columns are longitudinally arranged, and the exit modules in the two columns are staggered.

[0008] More preferably, the first exit module is in the first column of exit modules, the exit modules in the first column are horizontally parallel, and the exit modules in the first column are diagonally parallel.

[0009] Preferably, the double fiber polarization maintaining collimator comprises a polarization maintaining lens and two polarization maintaining fibers arranged in the lens, and the two polarization maintaining fibers are vertically or horizontally arranged.

[0010] Preferably, the birefringent crystal is calcite.

[0011] Compared with the prior art, the multi-channel polarization multiplexing and wavelength division multiplexing hybrid module has the advantages that: the wavelength division multiplexing function is added on the basis of simple polarization multiplexing / demultiplexing, so that the polarization signal can also load specific wavelength signals, the signals are connected with each other through a free space optical path, N different wavelengths have 2N signal multiplexing in one optical fiber, the 2N signals will not interfere due to different wavelengths and polarization states, and can be transmitted simultaneously in the same optical fiber, which is equivalent to increasing the capacity of the optical fiber signal by 2N times, and more use scenarios can be expanded, and the state changes of multiple targets can be monitored simultaneously in complex situations. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 It is a typical multi-channel wavelength division multiplexing module structure in the prior art.

[0013] Figure 2 It is a schematic diagram of the multi-channel polarization multiplexing and wavelength division multiplexing hybrid module provided by the utility model. Figure 1 .

[0014] Figure 3The utility model provides a kind of schematic diagram of multi-channel polarization multiplexing and wave division multiplexing hybrid module Figure 2 .

[0015] Figure 4 The utility model provides a kind of schematic diagram of double fiber polarization maintaining collimator of multi-channel polarization multiplexing and wave division multiplexing hybrid module.

[0016] Figure 5 The utility model provides a kind of first kind of implementation way setting schematic diagram of polarization maintaining fiber in multi-channel polarization multiplexing and wave division multiplexing hybrid module.

[0017] Figure 6 The utility model provides a kind of second kind of implementation way setting schematic diagram of polarization maintaining fiber in multi-channel polarization multiplexing and wave division multiplexing hybrid module. DETAILED DESCRIPTION

[0018] According to the preferred embodiment of the utility model provided by the drawings is specifically described.

[0019] Figures 2 to 6 The utility model provides a kind of preferred embodiment of multi-channel polarization multiplexing and wave division multiplexing hybrid module. As Figures 2 to 6As shown, the multi-channel polarization multiplexing and wavelength division multiplexing hybrid module includes an incident fiber collimator 10 for incident light signals and N exit modules 20, N being an integer greater than or equal to 2, each exit module 20 including a filter 21 for filtering light signals, a birefringent crystal 22 for forming two mutually perpendicular polarized lights from the polarized light passing through the filter, and a dual-fiber polarization maintaining collimator 23 for passing the two perpendicular polarized lights; the plurality of exit modules 20 are divided into a first exit module 1 for emitting a first light signal, a second exit module 2 for receiving the light signal reflected by the filter in the first exit module and emitting a second light signal, and an Nth exit module N for receiving the light signal reflected by the filter in the (N-1)th exit module and emitting an Nth light signal; the incident fiber collimator 10 is connected with an input fiber 11, the input fiber 11 being a common fiber serving as a common end, and multi-wavelength signals λ1...λn being input from the fiber 11; each exit module 20 forms an optical transmission channel, and the dual-fiber polarization maintaining collimator 23 of each exit module 20 is connected with two polarization maintaining fibers 201 and 202 serving as output ends; the multi-wavelength signals are filtered by the filter 21 in the first exit module 1, and the wavelength λ1 is transmitted and the wavelengths λ2...λn are reflected, the transmitted wavelength λ1 is divided into two mutually perpendicular polarized lights by the birefringent crystal 22, and the two mutually perpendicular polarized lights are received by the two polarization maintaining fibers 201 and 202 of the dual-fiber collimator 23, the second exit module 2 receives the reflected wavelengths λ2...λn, the filter 21 in the second exit module 2 filters the received light signals, transmits the wavelength λ2 and reflects the wavelengths λ3...λn, the transmitted wavelength λ2 is divided into two mutually perpendicular polarized lights by the birefringent crystal 22, and the two mutually perpendicular polarized lights are received by the two polarization maintaining fibers 201 and 202 of the dual-fiber collimator 23, and the same applies to the subsequent exit modules, thereby completing the filtering and polarization state loading output of the multi-channel N wavelengths.

[0020] The plurality of exit modules 20 are divided into a first column of exit modules 100 and a second column of exit modules 200, the exit modules in the first and second columns of exit modules are arranged longitudinally, and the exit modules in the two columns of exit modules are arranged in a staggered manner, so that the filter 21 in an exit module 20 at a rear position can receive the light signal reflected by the filter 21 in the previous exit module 20, thereby completing the filtering and polarization state loading output of the multi-channel N wavelengths.

[0021] As shown in FIG. 1, the multi-channel polarization multiplexing and wavelength division multiplexing hybrid module includes an incident fiber collimator 10 for incident light signals and N exit modules 20, N being an integer greater than or equal to 2, each exit module 20 including a filter 21 for filtering light signals, a birefringent crystal 22 for forming two mutually perpendicular polarized lights from the polarized light passing through the filter, and a dual-fiber polarization maintaining collimator 23 for passing the two perpendicular polarized lights; the plurality of exit modules 20 are divided into a first exit module 1 for emitting a first light signal, a second exit module 2 for receiving the light signal reflected by the filter in the first exit module and emitting a second light signal, and an Nth exit module N for receiving the light signal reflected by the filter in the (N-1)th exit module and emitting an Nth light signal; the incident fiber collimator 10 is connected with an input fiber 11, the input fiber 11 being a common fiber serving as a common end, and multi-wavelength signals λ1...λn being input from the fiber 11; each exit module 20 forms an optical transmission channel, and the dual-fiber polarization maintaining collimator 23 of each exit module 20 is connected with two polarization maintaining fibers 201 and 202 serving as output ends; the multi-wavelength signals are filtered by the filter 21 in the first exit module 1, and the wavelength λ1 is transmitted and the wavelengths λ2...λn are reflected, the transmitted wavelength λ1 is divided into two mutually perpendicular polarized lights by the birefringent crystal 22, and the two mutually perpendicular polarized lights are received by the two polarization maintaining fibers 201 and 202 of the dual-fiber collimator 23, the second exit module 2 receives the reflected wavelengths λ2...λn, the filter 21 in the second exit module 2 filters the received light signals, transmits the wavelength λ2 and reflects the wavelengths λ3...λn, the transmitted wavelength λ2 is divided into two mutually perpendicular polarized lights by the birefringent crystal 22, and the two mutually perpendicular polarized lights are received by the two polarization maintaining fibers 201 and 202 of the dual-fiber collimator 23, and the same applies to the subsequent exit modules, thereby completing the filtering and polarization state loading output of the multi-channel N wavelengths. Figure 1 and Figure 2As shown, the first exit module 1 is located at the first position of the first column of exit modules 100, so that the exit modules with odd serial numbers are distributed in the first column of exit modules 100, and the exit modules with even serial numbers are distributed in the second column of exit modules 100. The exit modules in the first column of exit modules 100 are horizontally parallel, and the exit modules in the second column of exit modules 200 are diagonally parallel, so that the light signals emitted or entered from each column of exit modules 20 are parallel.

[0022] The dual-fiber polarization maintaining collimator 23 comprises a polarization maintaining lens 231 and two polarization maintaining fibers 201 and 202 arranged in the lens, and the two polarization maintaining fibers are arranged vertically or horizontally. The dual-fiber polarization maintaining collimator 23 is assembled by the two polarization maintaining fibers 201 and 202 and the polarization maintaining lens 231, and the arrangement of the fibers is observed from the separate drawing of the dual-fiber structure as Figure 4 As shown, it can be seen from the left view that the two polarization maintaining fibers 201 and 202 are arranged vertically, which is an embodiment, and horizontal arrangement can also be adopted. The spacing of the polarization maintaining fibers 201 and 202 can be adjusted according to actual needs, and after the polarization maintaining fibers 201 and 202 are enlarged, it can be seen that the connecting lines of the polarization maintaining fiber stress mechanisms are perpendicular to each other, as Figure 5 is one of the embodiments, as Figure 6 is another embodiment, and other arrangements can be adopted according to needs, and other similar polarization maintaining fibers can also be adopted.

[0023] The birefringent crystal is calcite, which is a common birefringent crystal and has obvious birefringence effect, and the refractive index thereof is very different in different directions, so that the incident light can be split into two beams of light with different propagation directions.

[0024] The multi-channel polarization multiplexing and wavelength division multiplexing hybrid module provided by the utility model simultaneously uses wavelength division multiplexing technology and polarization multiplexing technology, and can realize specific wavelength polarization multiplexing (MUX) and demultiplexing (DEMUX). Each exit module forms a channel.

[0025] The demultiplexing (DEMUX) principle is as Figure 2As shown, first take the first channel formed by the first exit module as an example to explain, the multi-wavelength signal λ1...λn is input from the input fiber 11 connected to the incident fiber collimator 10, and is filtered by the filter 21 of the first exit module 1, and the wavelength λ1 can be transmitted and the wavelength λ2...λn is reflected, the transmitted wavelength λ1 is divided into two polarization states perpendicular to each other by the birefringent crystal 22, and is received by the two polarization maintaining fibers 201 and 202 of the double fiber collimator 23 and transmitted while maintaining the polarization state; the signal of the second channel is obtained after being reflected by the filter 21 of the first exit module 1 and input from the single fiber collimator 01, and is filtered by the filter 21 of the second exit module 2, and the wavelength λ2 can be transmitted and the wavelength λ3...λn is reflected, the transmitted wavelength λ2 is divided into two polarization states perpendicular to each other by the birefringent crystal 22, and is received by the two polarization maintaining fibers 201 and 202 of the double fiber collimator 23 and transmitted while maintaining the polarization state; similarly, the filtering and polarization state loading output of the multi-channel N wavelengths are completed.

[0026] The multiplexing (MUX) principle is as shown in Figure 3 As shown, first take the first channel formed by the first exit module as an example to explain, the mutually perpendicular polarization lights are respectively input from the polarization maintaining fibers 201 and 202, and after focusing by the polarization maintaining lens 231 of the double fiber collimator 23, the polarization state is still perpendicular to each other, and then enters the birefringent crystal 22 and merges together, and then is filtered by the filter 21, and two light signals with mutually perpendicular polarization states but the same wavelength (both wavelengths are λ1) can be transmitted, and the two light signals with the same transmitted wavelength λ1 but perpendicular polarization state are received by the ordinary incident single fiber collimator 10, and are coupled by the incident fiber 11 and transmitted while maintaining the mutually perpendicular polarization state; take the second channel formed by the second exit module 2 as an example to explain, the mutually perpendicular polarization lights are respectively input from the polarization maintaining fibers 201 and 202, and after focusing by the polarization maintaining lens 231, the polarization state is still perpendicular to each other, and then enters the birefringent crystal 22 and merges together, and then is filtered by the optical filter 21, and two light signals with mutually perpendicular polarization states but the same wavelength (both wavelengths are λ2) can be transmitted, and the two light signals with the same transmitted wavelength λ2 but perpendicular polarization state are reflected by the optical filter 02 and input into the ordinary incident single fiber collimator 10 for reception, and are coupled by the incident fiber 11 and transmitted while maintaining the mutually perpendicular polarization state. Similarly, the loading and polarization state multiplexing output of the multi-channel N wavelengths are completed.

[0027] Further explanation, the demultiplexing (DEMUX) principle is as shown in Figure 2From left to right) is to separate the detection of 2 polarization state perpendicular polarization signal light o light and e light carrying specific wavelength optical signal, respectively from polarization maintaining optical fiber 201, 202 output, 1 carrying wavelength optical signal is divided into two polarization state perpendicular but the same wavelength signal by birefringent crystal 22, equivalent to the capacity becomes 2 times; while the multiplexing principle (MUX) is ( Figure 3 From right to left) 2 perpendicular polarization signals are input from two polarization maintaining optical fibers 201, 202, combined through birefringent crystal 22 and then loaded with specified wavelength through the filter, since the polarization maintaining optical fiber can maintain the polarization state of the signal transmission, so that the combined two signals can be transmitted in one fiber at the same time without interference, the same wavelength signal loaded with two polarization states, equivalent to the capacity of the fiber signal becomes 2 times. Similarly, by analogy, N different wavelengths are loaded with two polarization states to form 2N different signals, 2N signals are connected with each other through free space optical path, and 2N signals are multiplexed in one optical fiber. Since the 2N signals have different wavelengths and polarization states and will not interfere with each other, they can be transmitted in the same optical fiber at the same time, equivalent to the capacity of N wavelength signals is doubled.

[0028] In summary, the technical scheme of the utility model can fully and effectively achieve the above-mentioned utility model purposes, and the structure and function principle of the utility model have been fully verified in the embodiments, and the expected effects and purposes can be achieved. Without departing from the principles and essence of the utility model, various changes or modifications can be made to the embodiments of the utility model. Therefore, the utility model includes all the alternatives mentioned in the patent application range, and any equivalent changes made within the scope of the utility model application patent range are within the scope of the patent application.

Claims

1. A multi-channel polarization and wavelength division multiplexing hybrid module, characterized by, The device comprises an incident fiber collimator for incident light signals and N exit modules, N being an integer greater than or equal to 2, each exit module comprising a filter for filtering light signals, a birefringent crystal for polarizing light signals passing through the filter into mutually perpendicular polarized light, and a dual-fiber polarization maintaining collimator for the two perpendicular polarized light to pass through; the plurality of exit modules are divided into a first exit module for emitting a first light signal, a second exit module for receiving light signals reflected by the filter in the first exit module and emitting a second light signal, and an Nth exit module for receiving light signals reflected by the filter in an (N-1)th exit module and emitting an Nth light signal.

2. The multi-channel polarization and wavelength division multiplexing hybrid module of claim 1, wherein: The plurality of exit modules are divided into a first column of exit modules and a second column of exit modules, the exit modules in the first and second columns are longitudinally arranged, and the exit modules in the two columns are staggered.

3. The multi-channel polarization and wavelength division multiplexing hybrid module of claim 2, wherein: The first exit module is in the first column of exit modules, the exit modules in the first column are horizontally parallel, and the exit modules in the first column are diagonally parallel.

4. The multi-channel polarization and wavelength division multiplexing hybrid module of claim 1, wherein: The dual-fiber polarization maintaining collimator comprises a polarization maintaining lens and two polarization maintaining fibers arranged in the lens.

5. The multi-channel polarization and wavelength division multiplexing hybrid module of claim 4, wherein: The two polarization maintaining fibers are vertically or horizontally arranged.

6. The multi-channel polarization and wavelength division multiplexing hybrid module of claim 1, wherein: The birefringent crystal is calcite.

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