TRANSMISSION METHOD AND SYSTEM FOR IMPROVED UNIDIRECTIONAL OR BIDIRECTIONAL DATA TRANSMISSION OVER TELECOMMUNICATION NETWORK, POLARIZATION ATTRACTOR CIRCUIT, COMPUTER PROGRAM AND COMPUTER PROGRAM PRODUCT

Abstract

The subject matter of the invention relates to a transmission method and system (100; 200) for improved unidirectional or bidirectional data transmission over a telecommunication network, a polarization attractor circuit (A1, A2; B1, B2), a computer program and a computer program product therefore.

Claims

1. A polarization attractor circuit (A1; A2; B2) designed for an improved bidirectional data transmission over a telecommunications network, characterized in that it comprises: polarization controllers (PC1, PC2; PC5, PC6), respectively, designed for changing the polarization state of signals, wherein said polarization controllers (PC1, PC2; PC5, PC6) are connected to at least one polarizing beam splitter (PBS1; PBS4), respectively, wherein at least one polarizing beam splitter (PBS1; PBS4) is designed for combining signals into a common output of the polarizing beam splitter (PBS1; PBS4) on the one side in one data transmission direction and for splitting signals into separate outputs from said polarizing beam splitter (PBS1; PBS4) and on the other side in the opposite data transmission direction, wherein said at least one polarizing beam splitter (PBS1; PBS4) is connected to a switching element (F1; F3), respectively, which in turn is connected to switching element (F2; F4), respectively, and to a polarization controller (PC3; PC7), respectively, wherein the polarization controller (PC3; PC7) is connected to an attenuator (VOA1; VOA2), respectively, and said attenuator (VOA1; VOA2) is connected to a splitting element (S1; S3), respectively, which in turn is connected to a nonlinear element (NLE1; NLE2), respectively, through which nonlinear element (NLE1; NLE2) is connected to a coupling element (S2; S4), respectively, wherein said coupling element (S2; S4) is subsequently connected to the switching element (F2; F4), respectively, and to the polarization controller (PC4; PC8), respectively, through which polarization controller (PC4; PC8) is connected to a polarizing beam splitter (PBS2; PBS3), respectively, which in turn is connected to a pump laser (LP1; LP2), respectively.

2. The circuit (A1; A2; B2) according to claim 1, characterized in that said polarization controller (PC1; PC5) is a horizontal polarization controller and said polarization controller (PC2; PC6) is a vertical polarization controller.

3. The circuit (A1; A2; B2) according to claim 1, characterized in that said polarization controller (PC3; PC7) is a linear polarization controller with the inclination angle of 45 relative to the axis of operation of the polarizing beam splitter (PBS1; PBS4).

4. The circuit (A1; A2; B2) according to claim 1, characterized in that said switching elements (F1, F2; F3, F4) are optical or optoelectronic.

5. The circuit (A1; A2; B2) according to claim 1, characterized in that said non-linear element (NLE1; NLE2) consists of at least several sections of the same or different length which falls within the range from 0.1 km to 50 km and of the same or different nonlinearity levels which fall within the range from 0.51/W.Math.km to 111/W.Math.km.

6. The circuit (A1; A2; B2) according to claim 1, characterized in that it comprises at least one programmable managing element (PME1; PME2) connected to said attenuator (VOA1; VOA2), respectively, and/or to said polarization controller (PC4; PC8), respectively, and/or to said pump laser (LP1; LP2), respectively.

7. The circuit (A1; A2; B2) according to claim 6, characterized in that at least one said programmable managing element (PME1; PME2) has at least one measurement sensor incorporated in its structure and designed for monitoring at least one environmental parameter.

8. The circuit (A1; A2; B2) according to claim 1, characterized in that said attenuator (VOA1; VOA2) is optical or optoelectronic.

9. The circuit (A1; A2; B2) according to claim 1, characterized in that said pump laser (LP1; LP2) constitutes sets of lasers with adjusted spectral parameters.

10. The circuit (A1; A2; B2) according to claim 1, characterized in that said polarization controller (PC4; PC8) is a horizontal polarisation controller.

11. A polarization attractor circuit (B1) designed for an improved unidirectional data transmission over a telecommunications network, characterized in that it comprises polarization controllers (PC1, PC2) designed for changing the polarization state of signals, wherein said polarization controllers (PC1, PC2) are connected to at least one polarizing beam splitter (PBS1) designed to combine signals into a common output of the polarizing beam splitter (PBS1) in one data transmission direction.

12. The circuit (B1) according to claim 11, characterized in that polarisation controller (PC1) is a horizontal polarisation controller and polarisation controller (PC2) is a vertical polarisation controller.

13. A transmission method for an improved unidirectional or bidirectional data transmission over a telecommunication network consisting in that the end devices (EDA1_1, EDA1_2, . . . , EDA1_N) or (EDB1_1, EDB1_2, . . . , EDB1_N) and end devices (EDA2_1, EDA2_2, . . . , EDA2_N) or (EDB2_1, EDB2_2, . . . , EDB2_N) constitute part of the structure of transmission devices for data transmission using methods based on Wavelength Division Multiplexing (WDM) and/or methods based on Time Division Multiplexing (TDM) or methods based on Code Division Multiplexing (CDM), wherein the end devices (EDA1_1, EDA1_2, . . . , EDA1_N) or (EDB1_1, EDB1_2, . . . , EDB1_N) send signals having a predetermined wavelength via a transmission medium (110; 210) to the end devices (EDA2_1, EDA2_2, . . . , EDA2_N) or (EDB2_1, EDB2_2, . . . , EDB2_N), wherein the transmission medium (110; 210) is located in cable ducting, overhead or inside buildings, characterized in that signals having predetermined wavelengths are delivered from the end devices (EDA1_1, EDA1_2, . . . , EDA1_N) or (EDB1_1, EDB1_2, . . . , EDB1_N) to a first at least one polarization attractor circuit (A1; B1) as defined in any of claims 1 to 10 for the polarization attractor circuit (A1) or as defined in any of claims 11 to 12 for the polarization attractor circuit (B1), and then the signals are delivered via the transmission medium (110; 210) to the second at least one polarization attractor circuit (A2; B2) as defined in any of claims 1 to 10 for the polarization attractor circuit (A2; B2) and from thereto the end devices (EDA2_1, EDA2_2, . . . , EDA2_N) or (EDB2_1, EDB2_2, . . . , EDB2_N).

14. The method according to claim 13, characterized in that for the polarization attractor circuit (A1; B1), signals with predetermined wavelengths are delivered to the inputs of polarization controller (PC1) and (PC2), wherein the signals with predetermined wavelengths received in the polarization controller (PC1) and (PC2) are subjected to a change of polarization state by performing horizontal polarization in the polarization controller (PC1), and by performing vertical polarization in the polarization controller (PC2), to the above-mentioned signals with predetermined wavelengths are given orthogonal polarization states; subsequently, the signals with predetermined wavelengths subjected to a change of polarization state are delivered from the outputs of polarization controllers (PC1) and (PC2) to separate inputs of at least one polarizing beam splitter (PBS1) in which said signals are combined in such a way that multiplied-polarization signals with predetermined wavelengths are obtained at the common output of at least one polarizing beam splitter (PBS1); in the case of the polarization attractor circuit (A1), such multiplied-polarization signals with predetermined wavelengths are delivered to the input of the switching element (F1) which directs these signals to the input of the switching element (F2) by means of which the signals are placed in the transmission medium (110); wherein in the case of the polarization attractor circuit (B1), such polarization-multiplied signals with predetermined wavelengths are placed immediately in the transmission medium (210); these polarization-multiplied signals with predetermined wavelengths are sent by means of the transmission medium (110; 210) to the input of the switching element (F4) located in the second polarization attractor circuit (A2; B2); subsequently, the signals are sent by means of said switching element (F4) to the input of the coupling element (S4) in which these multiplied signals with predetermined wavelengths are combined with the signal of a pump wave with a predetermined wavelength originating from a pump laser (LP2); wherein said signal of a pump wave with a predetermined wavelength from the pump laser (LP2), before it reaches said coupling element (S4), is delivered from the pump laser (LP2) to the input of the polarizing beam splitter (PBS3); subsequently, the signal of a pump wave with a predetermined wavelength from the pump laser (LP2) is sent from the output of the polarizing beam splitter (PBS3) to the input of polarization controller (PC8) in which said signal of a pump wave with a predetermined wavelength from the pump laser (LP2) is subjected to a change of polarization state into a horizontal polarization state of the signal of the pump wave with the predetermined wavelength; subsequently, the signal of a pump wave with a predetermined wavelength from the pump laser (LP2) is delivered from the output of polarization controller (PC8) to the input of said coupling element (S4) in which the above-mentioned combining of signals takes place and the signals are delivered to the input of the non-linear element (NLE2); wherein in the non-linear element (NLE2), interaction based on stimulated Raman scattering occurs between the signal of a pump wave with a predetermined wavelength from the pump laser (LP2), and by means of multiplied signals with predetermined wavelengths, result in a change of the polarization state, degree of polarization and signal strength; subsequently, the multiplied signals with predetermined wavelengths and the signal of a pump wave with a predetermined wavelength from the pump laser (LP2) are delivered from the output of the non-linear element (NLE2) to the input of the splitting element (S3); wherein the signal of a pump wave with a predetermined wavelength from the pump laser (LP2) is separated by means of splitting element (S3) from the multiplied signals with predetermined wavelengths by means of a band-pass filter; then the multiplied signals with predetermined wavelengths are delivered to the input of the attenuator (VOA2) which adjusts the signal strength by attenuating to a specific predetermined level; subsequently, the multiplied signals with predetermined wavelengths are delivered from the output of attenuator (VOA2) to the input of polarization controller (PC7) by means of which their polarization state changes and the above-mentioned signals are thus transformed into orthogonal polarization states by performing linear polarization with the inclination angle of 45 relative to the axis of operation of polarizing beam splitter (PBS4); subsequently, the signals with predetermined wavelengths subjected to change of polarization state are delivered to the input of the switching element (F3) by means of which the signals are delivered to the common input of the polarization beam splitter (PBS4) in which the signals with predetermined wavelengths are split and delivered to the separate outlets of said polarization beam splitter (PBS4); wherein separated signals with predetermined wavelengths are sent from said outputs of polarizing beam splitter (PBS4) to the input of polarization controller (PC5) and (PC6), and subsequently to respective outputs of the polarization attractor circuit (A2; B2) and from thereto the end devices (EDA2_1, EDA2_2, . . . , EDA2_N) or (EDB2_1, EDB2_2, . . . , EDB2_N), whereas signals with predetermined wavelengths in the opposite data transmission direction are delivered from the end devices (EDA2_1, EDA2_2, . . . , EDA2_N) to the input of polarization controllers (PC5) and (PC6) located in the polarization attractor circuit (A2), said signals with predetermined wavelengths being subjected to analogous operations during their way through the above-described connections in the opposite data transmission direction as those for the signals with predetermined wavelengths which are delivered from the end devices (EDA1_1, EDA1_2, . . . , EDA1_N).

15. The method according to claim 14, characterized in that the polarization state of signals with predetermined wavelengths is changed manually or automatically by means of polarization controller (PC1, PC2; PC5, PC6).

16. The method according to claim 13, characterized in that signals with predetermined wavelength fall within the range of 1500 nm to 1570 nm in one data transmission direction and within the range of 1470 nm to 1500 nm in the opposite data transmission direction.

17. The method according to claim 14, characterized in that a signal with predetermined wavelength from a pump laser (LP1; LP2) falls within the range of 1400 to 1460 nm.

18. The method according to claim 14, characterized in that said attenuator (VOA1; VOA2) and/or said polarization controller (PC4, PC8) and/or said pump laser (LP1; LP2) are electronically or mechanically controlled by means of at least one programmable managing element (PME1; PME2).

19. The method according to claim 18, characterized in that at least one programmable managing element (PME1; PME2) additionally monitors at least one environmental parameter by means of at least one measurement sensor incorporated in its structure.

20. The method according to claim 19, characterized in that mechanical tension of the polarization attractor circuit (A1; A2; B2) structure and/or atmospheric pressure and/or temperature level and/or humidity level and/or levelling of the polarization attractor circuit (A1; A2; B2) are monitored by means of at least one measurement sensor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0063] The subject matter of the invention is shown in the exemplary embodiment, with reference to the attached drawings, wherein:

[0064] FIG. 1 is a block diagram concerning the transmission method and system with bidirectional data transmission in one embodiment using the designed polarization attractor circuits according to the invention;

[0065] FIG. 2 is a block diagram concerning the transmission method and system with unidirectional data transmission in another embodiment using the designed polarization attractor circuits according to the invention.

EMBODIMENTS

[0066] The following numbered embodiments are contemplated and are non-limiting: [0067] 1. A polarization attractor circuit (A1; A2; B2) designed for an improved bidirectional data transmission over a telecommunications network, characterized in that it comprises: polarization controllers (PC1, PC2; PC5, PC6), respectively, designed for changing the polarization state of signals, wherein said polarization controllers (PC1, PC2; PC5, PC6) are connected to at least one polarizing beam splitter (PBS1; PBS4), respectively, wherein at least one polarizing beam splitter (PBS1; PBS4) is designed for combining signals into a common output of the polarizing beam splitter (PBS1; PBS4) on the one side in one data transmission direction and for splitting signals into separate outputs from said polarizing beam splitter (PBS1; PBS4) and on the other side in the opposite data transmission direction, wherein said at least one polarizing beam splitter (PBS1; PBS4) is connected to a switching element (F1; F3), respectively, which in turn is connected to switching element (F2; F4), respectively, and to a polarization controller (PC3; PC7), respectively, wherein the polarization controller (PC3; PC7) is connected to an attenuator (VOA1; VOA2), respectively, and said attenuator (VOA1; VOA2) is connected to a splitting element (S1; S3), respectively, which in turn is connected to a nonlinear element (NLE1; NLE2), respectively, through which nonlinear element (NLE1; NLE2) is connected to a coupling element (S2; S4), respectively, wherein said coupling element (S2; S4) is subsequently connected to the switching element (F2; F4), respectively, and to the polarization controller (PC4; PC8), respectively, through which polarization controller (PC4; PC8) is connected to a polarizing beam splitter (PBS2; PBS3), respectively, which in turn is connected to a pump laser (LP1; LP2), respectively. [0068] 2. The circuit (A1; A2; B2) according to clause 1, characterized in that said polarization controller (PC1; PC5) is a horizontal polarization controller and said polarization controller (PC2; PC6) is a vertical polarization controller. [0069] 3. The circuit (A1; A2; B2) according to clause 1, characterized in that said polarization controller (PC3; PC7) is a linear polarization controller with the inclination angle of 45 relative to the axis of operation of the polarizing beam splitter (PBS1; PBS4). [0070] 4. The circuit (A1; A2; B2) according to clause 1, characterized in that said switching elements (F1, F2; F3, F4) are optical or optoelectronic. [0071] 5. The circuit (A1; A2; B2) according to clause 1, characterized in that said non-linear element (NLE1; NLE2) consists of at least several sections of the same or different length which falls within the range from 0.1 km to 50 km and of the same or different nonlinearity levels which fall within the range from 0.51/W.Math.km to 111/W.Math.km. [0072] 6. The circuit (A1; A2; B2) according to clause 1, characterized in that it comprises at least one programmable managing element (PME1; PME2) connected to said attenuator (VOA1; VOA2), respectively, and/or to said polarization controller (PC4; PC8), respectively, and/or to said pump laser (LP1; LP2), respectively. [0073] 7. The circuit (A1; A2; B2) according to clause 6, characterized in that at least one said programmable managing element (PME1; PME2) has at least one measurement sensor incorporated in its structure and designed for monitoring at least one environmental parameter. [0074] 8. The circuit (A1; A2; B2) according to clause 1 or 6, characterized in that said attenuator (VOA1; VOA2) is optical or optoelectronic. [0075] 9. The circuit (A1; A2; B2) according to clause 1 or 6, characterized in that said pump laser (LP1; LP2) constitutes sets of lasers with adjusted spectral parameters. [0076] 10. The circuit (A1; A2; B2) according to clause 1 or 6, characterized in that said polarization controller (PC4; PC8) is a horizontal polarisation controller. [0077] 11. A polarization attractor circuit (B1) designed for an improved unidirectional data transmission over a telecommunications network, characterized in that it comprises polarization controllers (PC1, PC2) designed for changing the polarization state of signals, wherein said polarization controllers (PC1, PC2) are connected to at least one polarizing beam splitter (PBS1) designed to combine signals into a common output of the polarizing beam splitter (PBS1) in one data transmission direction. [0078] 12. The circuit (B1) according to clause 11, characterized in that polarisation controller (PC1) is a horizontal polarisation controller and polarisation controller (PC2) is a vertical polarisation controller. [0079] 13. A transmission system (100; 200) for an improved unidirectional or bidirectional data transmission over a telecommunication network in which end devices (EDA1_1, EDA1_2, . . . , EDA1_N) or (EDB1_1, EDB1_2, . . . , EDB1_N) and end devices (EDA2_1, EDA2_2, . . . , EDA2_N) or (EDB2_1, EDB2_2, . . . , EDB2_N) constitute part of the structure of transmission devices for data transmission using methods based on wave division multiplexing (WDM) and/or methods based on Time Division Multiplexing (TDM) or methods based on code division multiplexing (CDM), wherein end devices (EDA1_1, EDA1_2, . . . , EDA1_N) or (EDB1_1, EDB1_2, . . . , EDB1_N) are connected through a transmission medium (110; 210) with end devices (EDA2_1, EDA2_2, . . . , EDA2_N) or (EDB2_1, EDB2_2, . . . , EDB2_N), wherein the transmission medium (110; 210) is located in cable ducting, overhead or inside buildings, characterized in that between the end devices (EDA1_1, EDA1_2, . . . , EDA1_N) or (EDB1_1, EDB1_2, . . . , EDB1_N) and the transmission medium (110; 210), there is located a first at least one polarization attractor circuit (A1; B1) as defined in any of clauses 1 to 10 for the polarization attractor circuit (A1) and as defined in any of clauses 11 to 12 for the polarization attractor circuit (B1), and between the transmission medium (110, 210) and the end devices (EDA2_1, EDA2_2, . . . , EDA2_N) or (EDB2_1, EDB2_2, . . . , EDB2_N) there is located a second at least one polarization attractor circuit (A2; B2) as defined in any of clauses 1 to 10 for the polarization attractor circuit (A2; B2). [0080] 14. The system according to clause 13, characterized in that the transmission medium (110; 210) is a transmission optical fibre. [0081] 15. The system according to clause 13 or 14, characterized in that a transmission optical fibre used as the transmission medium (110; 210) has the same nonlinearity level as the non-linear element (NLE1; NLE2). [0082] 16. A transmission method for an improved unidirectional or bidirectional data transmission over a telecommunication network consisting in that the end devices (EDA1_1, EDA1_2, . . . , EDA1_N) or (EDB1_1, EDB1_2, . . . , EDB1_N) and end devices (EDA2_1, EDA2_2, . . . , EDA2_N) or (EDB2_1, EDB2_2, . . . , EDB2_N) constitute part of the structure of transmission devices for data transmission using methods based on Wavelength Division Multiplexing (WDM) and/or methods based on Time Division Multiplexing (TDM) or methods based on Code Division Multiplexing (CDM), wherein the end devices (EDA1_1, EDA1_2, . . . , EDA1_N) or (EDB1_1, EDB1_2, . . . , EDB1_N) send signals having a predetermined wavelength via a transmission medium (110; 210) to the end devices (EDA2_1, EDA2_2, . . . , EDA2_N) or (EDB2_1, EDB2_2, . . . , EDB2_N), wherein the transmission medium (110; 210) is located in cable ducting, overhead or inside buildings, characterized in that signals having predetermined wavelengths are delivered from the end devices (EDA1_1, EDA1_2, . . . , EDA1_N) or (EDB1_1, EDB1_2, . . . , EDB1_N) to a first at least one polarization attractor circuit (A1; B1) as defined in any of clauses 1 to 10 for the polarization attractor circuit (A1) or as defined in any of clauses 11 to 12 for the polarization attractor circuit (B1), and then the signals are delivered via the transmission medium (110; 210) to the second at least one polarization attractor circuit (A2; B2) as defined in any of clauses 1 to 10 for the polarization attractor circuit (A2; B2) and from thereto the end devices (EDA2_1, EDA2_2, . . . , EDA2_N) or (EDB2_1, EDB2_2, . . . , EDB2_N). [0083] 17. The method according to clause 16, characterized in that for the polarization attractor circuit (A1; B1), signals with predetermined wavelengths are delivered to the inputs of polarization controller (PC1) and (PC2), wherein the signals with predetermined wavelengths received in the polarization controller (PC1) and (PC2) are subjected to a change of polarization state by performing horizontal polarization in the polarization controller (PC1), and by performing vertical polarization in the polarization controller (PC2), to the above-mentioned signals with predetermined wavelengths are given orthogonal polarization states; [0084] subsequently, the signals with predetermined wavelengths subjected to a change of polarization state are delivered from the outputs of polarization controllers (PC1) and (PC2) to separate inputs of at least one polarizing beam splitter (PBS1) in which said signals are combined in such a way that multiplied-polarization signals with predetermined wavelengths are obtained at the common output of at least one polarizing beam splitter (PBS1); [0085] in the case of the polarization attractor circuit (A1), such multiplied-polarization signals with predetermined wavelengths are delivered to the input of the switching element (F1) which directs these signals to the input of the switching element (F2) by means of which the signals are placed in the transmission medium (110); [0086] wherein in the case of the polarization attractor circuit (B1), such polarization-multiplied signals with predetermined wavelengths are placed immediately in the transmission medium (210); [0087] these polarization-multiplied signals with predetermined wavelengths are sent by means of the transmission medium (110; 210) to the input of the switching element (F4) located in the second polarization attractor circuit (A2; B2); [0088] subsequently, the signals are sent by means of said switching element (F4) to the input of the coupling element (S4) in which these multiplied signals with predetermined wavelengths are combined with the signal of a pump wave with a predetermined wavelength originating from a pump laser (LP2); [0089] wherein said signal of a pump wave with a predetermined wavelength from the pump laser (LP2), before it reaches said coupling element (S4), is delivered from the pump laser (LP2) to the input of the polarizing beam splitter (PBS3); [0090] subsequently, the signal of a pump wave with a predetermined wavelength from the pump laser (LP2) is sent from the output of the polarizing beam splitter (PBS3) to the input of polarization controller (PC8) in which said signal of a pump wave with a predetermined wavelength from the pump laser (LP2) is subjected to a change of polarization state into a horizontal polarization state of the signal of the pump wave with the predetermined wavelength; [0091] subsequently, the signal of a pump wave with a predetermined wavelength from the pump laser (LP2) is delivered from the output of polarization controller (PC8) to the input of said coupling element (S4) in which the above-mentioned combining of signals takes place and the signals are delivered to the input of the non-linear element (NLE2); [0092] wherein in the non-linear element (NLE2), interaction based on stimulated Raman scattering occurs between the signal of a pump wave with a predetermined wavelength from the pump laser (LP2), and by means of multiplied signals with predetermined wavelengths, result in a change of the polarization state, degree of polarization and signal strength; [0093] subsequently, the multiplied signals with predetermined wavelengths and the signal of a pump wave with a predetermined wavelength from the pump laser (LP2) are delivered from the output of the non-linear element (NLE2) to the input of the splitting element (S3); [0094] wherein the signal of a pump wave with a predetermined wavelength from the pump laser (LP2) is separated by means of splitting element (S3) from the multiplied signals with predetermined wavelengths by means of a band-pass filter; [0095] then the multiplied signals with predetermined wavelengths are delivered to the input of the attenuator (VOA2) which adjusts the signal strength by attenuating to a specific predetermined level; [0096] subsequently, the multiplied signals with predetermined wavelengths are delivered from the output of attenuator (VOA2) to the input of polarization controller (PC7) by means of which their polarization state changes and the above-mentioned signals are thus transformed into orthogonal polarization states by performing linear polarization with the inclination angle of 45 relative to the axis of operation of polarizing beam splitter (PBS4); [0097] subsequently, the signals with predetermined wavelengths subjected to change of polarization state are delivered to the input of the switching element (F3) by means of which the signals are delivered to the common input of the polarization beam splitter (PBS4) in which the signals with predetermined wavelengths are split and delivered to the separate outlets of said polarization beam splitter (PBS4); [0098] wherein separated signals with predetermined wavelengths are sent from said outputs of polarizing beam splitter (PBS4) to the input of polarization controller (PC5) and (PC6), and subsequently to respective outputs of the polarization attractor circuit (A2; B2) and from thereto the end devices (EDA2_1, EDA2_2, . . . , EDA2_N) or (EDB2_1, EDB2_2, . . . , EDB2_N), [0099] whereas signals with predetermined wavelengths in the opposite data transmission direction are delivered from the end devices (EDA2_1, EDA2_2, . . . , EDA2_N) to the input of polarization controllers (PC5) and (PC6) located in the polarization attractor circuit (A2), said signals with predetermined wavelengths being subjected to analogous operations during their way through the above-described connections in the opposite data transmission direction as those for the signals with predetermined wavelengths which are delivered from the end devices (EDA1_1, EDA1_2, . . . , EDA1_N). [0100] 18. The method according to clause 17, characterized in that the polarization state of signals with predetermined wavelengths is changed manually or automatically by means of polarization controller (PC1, PC2; PC5, PC6). [0101] 19. The method according to clause 16 or 17 or 18, characterized in that signals with predetermined wavelength fall within the range of 1500 nm to 1570 nm in one data transmission direction and within the range of 1470 nm to 1500 nm in the opposite data transmission direction. [0102] 20. The method according to clause 17, characterized in that a signal with predetermined wavelength from a pump laser (LP1; LP2) falls within the range of 1400 to 1460 nm. [0103] 21. The method according to clause 17, characterized in that said attenuator (VOA1; VOA2) and/or said polarization controller (PC4, PC8) and/or said pump laser (LP1; LP2) are electronically or mechanically controlled by means of at least one programmable managing element (PME1; PME2). [0104] 22. The method according to clause 21, characterized in that at least one programmable managing element (PME1; PME2) additionally monitors at least one environmental parameter by means of at least one measurement sensor incorporated in its structure. [0105] 23. The method according to clause 22, characterized in that mechanical tension of the polarization attractor circuit (A1; A2; B2) structure and/or atmospheric pressure and/or temperature level and/or humidity level and/or levelling of the polarization attractor circuit (A1; A2; B2) are monitored by means of at least one measurement sensor. [0106] 24. A computer program by means of which it is possible to remotely control and monitor the operation of the polarization attractor circuits (A1; A2; B2) in accordance with the proposed method, wherein all steps of the method may be performed according to one of the above clauses when the computer program is executed in at least one programmable managing element (PME1; PME2) and/or in a remotely localized computer and/or server platform. [0107] 25. A computer program product with a computer-readable medium and a computer program saved on a computer-readable medium and a program code, which enables performing the steps of the method according to one of the above clauses when the computer program is executed in at least one programmable managing element (PME1; PME2) and/or in a remotely localized computer and/or sever platform.

DETAILED DESCRIPTION OF THE INVENTION

[0108] The subject matter of the invention is described in detail below with reference to the attached Figures and exemplary embodiments. The present invention is not limited only to the detailed embodiments described herein.

[0109] The exemplary embodiment presented in FIG. 1. illustrates a transmission system 100 with bidirectional data transmission with the use of the designed polarization attractor circuit A1 and A2 according to the invention. Said transmission system 100 is constructed of a first polarization attractor circuit A1 located between an end device EDA1_1, EDA1_2 and a transmission medium 110, and a second polarization attractor circuit A2 located between the transmission medium 110 and an end device EDA2_1, EDA2_2. Both polarization attractor circuit A1 and A2 are designed for increasing data transmission speed.

[0110] In the presented embodiment, data transmission speed is doubled from 1 GB/s to about 2 GB/s in two directions using different wavelengthsin one direction in the range of 1480 nm to 1500 nm and in the other direction in the range of 1530 nm to 1570 nm by the transmission medium 110 which, in this exemplary embodiment, is in the form of a transmission optical fibre.

[0111] In the presented embodiment each polarization attraction circuit A1 and A2 comprises polarization controllers PC1, PC2; PC5, PC6 for the polarization attraction circuit A1 and A2, respectively, which are designed for changing the polarization state of signals; the polarization controller PC1; PC5 in the polarization attractor circuit A1 and A2, respectively, is a horizontal polarization controller whereas the polarization controller PC2; PC6 in the polarization attractor circuit A1 and A2, respectively, is a vertical polarization controller. Said polarization controllers PC1, PC2; PC5, PC6 are connected to a polarization beam splitter PBS1; PBS4 in the polarization attractor circuit A1 and A2, respectively; the polarization beam splitter PBS1; PBS4 is designed for combining signals into a common output of the polarization beam splitter PBS1; PBS4 on one side in one data transmission direction and for splitting signals into separate outputs from said polarization beam splitter PBS1; PBS4 on the other side in the opposite data transmission direction. Said polarization beam splitter PBS1; PBS4 is connected to a switching element F1; F3 in the polarization attractor circuit A1; A2, respectively, which is in turn connected to a switching element F2; F4 in the polarization attractor circuit A1; A2, respectively, and to a polarization controller PC3; PC7 in the polarization attractor circuit A1; A2, respectively, designed to change the polarization state of signals; the polarization controller PC3; PC7 in the polarization attractor circuit A1; A2, respectively, is a controller of 45 slant linear polarization relative to the axis of operation of the polarization beam splitter PBS1; PBS4. Said polarization controller PC3; PC7 is subsequently connected to an optical attenuator VOA1; VOA2 in the polarization attractor circuit A1; A2, respectively. The optical attenuator VOA1; VOA2 is designed for adjusting the level of signal strength at the input of the polarization controller PC3; PC7. Said optical attenuator VOA1; VOA2 is connected to a splitting element S1, S3 in the polarization attractor circuit A1 and A2, respectively, which is in turn connected to a nonlinear element NLE1; NLE2 in the polarization attractor circuit A1 and A2, respectively. In the present exemplary embodiment, said nonlinear element NLE1; NLE2 consists of 2 sections having the same length of 2 km and nonlinearity level of 51/W.Math.km and, in the present embodiment, it has a higher nonlinearity level than the transmission medium 110. In an optimal solution, the transmission medium 110 has the same nonlinearity level as the nonlinear element NLE1; NLE2. A splitting element S1; S3 is connected via said nonlinear element NLE1; NLE2 with a coupling element S2; S4 in the polarization attractor circuit A1; A2, respectively. Said coupling element S2; S4 makes it possible to aggregate signals into one fibre of said nonlinear element NLE1; NLE2. The coupling element S2; S4 is subsequently connected to the switching element F2; F4 and to the polarization controller PC4; PC8 in the polarization attractor circuit A1 and A2, respectively, designed for changing the polarization state of signals; the polarization controller PC4; PC8 in the polarization attractor circuit A1; A2, respectively, is a horizontal polarization controller. The said polarization controller PC4; PC8 is connected to the polarization beam splitter PBS2; PBS3 in the polarization attractor circuit A1; A2, respectively, which is in turn connected to a pump laser LP1; LP2 in the polarization attractor circuit A1; A2, respectively. Said optical attenuator VOA1; VOA2, polarization controller PC4; PC8 and pump laser LP1; LP2 are connected to a programmable managing element PME1; PME2 for the polarization attractor system A1; A2, respectively; said programmable managing element PME1; PME2 being additionally provided with five measurement sensors incorporated in its structure and designed for monitoring environmental parameters, such as mechanical tension of the structure of the polarization attractor circuit A1; A2, atmospheric pressure, temperature level, humidity level and levelling of the polarization attractor circuit A1; A2.

[0112] On the basis of the above described polarization attractor circuit A1 and A2, an exemplary embodiment of the method for bidirectional data transmission according to the invention will now be presented, which method is carried out as follows: [0113] Signals having wavelengths of 1550 nm sent in one data transmission direction in the present embodiment are delivered from end devices EDA1_1, EDA2_2 constituting part of the structure of transmission devices to the input of the polarization controller PC1 and PC2 located in the first polarization attractor circuit A1. Signals having wavelengths of 1550 nm supplied to said polarization controller PC1 and PC2 are subjected to a change of polarization state and thus the above mentioned signals are given orthogonal polarization states by performing horizontal polarization in the polarization controller PC1 and by performing vertical polarization in the polarization controller PC2. Signals with wavelengths of 1550 nm subjected to a change of polarization state are subsequently delivered from the output of polarization the controller PC1 and PC2 to separate inputs of the polarization beam splitter PBS1 in which the signals are combined in such a way that polarization-multiplexed signals having a wavelength of 1550 nm are obtained at the common output of the polarization beam splitter PBS1. Such combined signals get to the input of the switching element F1 which directs these signals to the input of the switching element F2 which in turn places the signals in the transmission medium 110. In this embodiment, the transmission medium 110 is a transmission optical fibre via which the polarization-multiplexed signals having wavelengths of 1550 nm are sent to the input of the switching element F4 located in the second polarization attractor circuit A2. Subsequently, said switching element F4 delivers the signals to the input of the coupling element S4 which combines the multiplexed signals having wavelengths of 1550 nm with a pump wave signal which, in the embodiment, has a wavelength of 1455 nm and originates from the pump laser LP2. Said pump wave signal having the wavelength of 1455 nm from the pump laser LP2, before it reaches said coupling element S4, is supplied from the pump laser LP2 to the input of the polarization beam splitter PBS3. Subsequently, the pump wave signal having the wavelength of 1455 nm from the pump laser LP2 is delivered from the output of the polarization beam splitter PBS3 to the input of the polarization controller PC8 in which said pump wave signal having the wavelength of 1455 nm from the pump laser LP2 is subjected to a change of polarization state and said pump wave signal having the wavelength of 1455 nm is given horizontal polarization state in the present embodiment. Subsequently, the pump wave signal having the wavelength of 1455 nm from the pump laser LP2 is delivered from the output of the polarization controller PC8 to the input of said coupling element S4 in which the above mentioned combination of signals takes place and the signals are delivered to the input of the nonlinear element NL2. In the nonlinear element NL2 interaction based on Stimulated Raman Scattering occurs between the pump wave signal having the wavelength of 1455 nm from the pump laser LP2 and the multiplexed signals having wavelengths of 1550 nm. Stimulated Raman Scattering consists basically in scattering the pump wave power on the structural molecules of the nonlinear element's material as a result of which the pump wave transfers part of its energy to the material as vibration of its molecules. Due to vibration of the molecules of medium the remaining power of the pump wave signal is emitted within the band of signals having the wavelength of 1550 nm in one data transmission direction or signals having the wavelength of 1490 nm in the other, opposite data transmission direction for the pump wave signal having the wavelength of 1455 nm from the pump laser LP2 and the pump wave signal having the wavelength of 1400 nm from the pump laser LP1, respectively. This results in a change of polarization state, degree of polarization and level of signal power. Subsequently, the multiplexed signals having the wavelengths of 1550 nm and the pump wave signal having the wavelength of 1455 nm from the pump laser LP2 are delivered from the output of the nonlinear element NLE2 to the input of the splitting element S3. The splitting element S3 separates the pump wave signal having the wavelength of 1455 nm from the pump laser LP2 from the multiplexed signals having the wavelength of 1550 nm by means of a bandpass filter. Next, the multiplexed signals having the wavelength of 1550 nm are delivered to the input of the optical attenuator VOA2 which adjusts the signal power by attenuating it to a specific predetermined level, most frequently to the level of 3 dBm, i.e. 2 mW, which is equivalent to the double signal level typically used in optical telecommunication. However, this is each time dependent on such factors as for example cable layout, the level of signals having specific wavelengths, etc. Subsequently, the multiplied signals having the wavelength of 1550 nm are delivered from the output of the optical attenuator VOA2 to the input of the polarization controller PC7 which changes their state of polarization and thus the signals are given orthogonal polarization states by performing slant linear polarization at 45 relative to the axis of operation of the polarization beam splitter PBS4, and subsequently the signals having the wavelength of 1550 nm subjected to a change of polarization state are delivered to the input of the switching element F3 which delivers the signals to the common input of the polarization beam splitter PBS4 which splits the signals having the wavelength of 1550 nm and delivers them to the separate outputs of said polarization beam splitter PBS4. From said outputs of the polarization beam splitter PBS4, the split signals having the wavelength of 1550 nm get to input of the polarization controller PC5 and PC6 and subsequently to the respective outputs of the polarization attractor circuit A2 and from there to the end devices EDA2_1, EDA2_2.

[0114] In turn, signals having the wavelength of 1490 nm are sent in the opposite data transmission direction and in the present example embodiment they are delivered from the end devices EDA2_1, EDA2_2 constituting part of the structure of transmission devices to the inputs of the polarization controllers PC5 and PC6 located in the polarization attractor circuit A2. Said signals having the wavelengths of 1490 nm are subjected to analogous operations, when travelling along the above described route of connections in the opposite data transmission direction, as the signals having the wavelength of 1550 nm which are delivered from the end devices EDA1_1, EDA1_2.

[0115] In the above embodiment of the method for bidirectional data transmission according to the invention said optical attenuator VOA1; VOA2, polarization controller PC4; PC8 and pump laser LP1; PL2 in the polarization attractor circuit A1 and A2, respectively, are electronically controlled by means of a programmable managing element PME1; PME2 in the polarization attractor circuit A1 and A2, respectively. Additionally, the programmable managing element PME1; PME2, respectively, in polarization attractor circuit A1 and A2, also monitors, by means of five measurement sensors incorporated in its structure, environmental parameters such as mechanical tension of the structure of the polarization attractor circuit A1; A2, atmospheric pressure, temperature level, humidity level and levelling of the polarization attractor circuit A1; A2.

[0116] The next exemplary embodiment presented in FIG. 2 illustrates a transmission system 200 with unidirectional data transmission with the use of the designed polarization attractor system B1 and B2 according to the invention. Said transmission system 200, just like the transmission system 100 illustrated in FIG. 1, is constructed of a first polarization attractor circuit B1 located between an end device EDB1_1, EDB1_2 and a transmission medium 210, and a second polarization attractor circuit B2 located between the transmission medium 210 and an end device EDB2_1, EDB2_2. In this case data transmission is unidirectional only since the polarization attractor circuit B1 is modified compared to the polarization attractor circuit A1 in FIG. 1. The polarization attractor circuit B1 is simplified in this embodiment to connections between polarization controllers PC1, PC2 and a polarization beam splitter PBS1. The functionality of the polarization attractor circuit B2 in terms of how it affects signals having wavelengths of 1550 nm remains unchanged compared to the embodiment presented in FIG. 1.

[0117] In the above exemplary embodiment data transmission speed is also doubled from 1 GB/s to about 2 GB/s but in one direction only and using the wavelength range of 1530 nm to 1570 nm via a transmission medium 210 which in this embodiment is also in the form of a transmission optical fibre.

[0118] In summary, in this embodiment the method provided in this case for unidirectional data transmission according to the invention is carried out as follows: [0119] Signals having a wavelength of 1550 nm transmitted in one data transmission direction in this embodiment are delivered from end devices EDB1_1, EDB1_2 constituting part of the structure of transmission devices to the inputs of polarization controllers PC1 and PC2 located in the first polarization attractor circuit B1. The signals having a wavelength of 1550 nm delivered to said polarization controllers PC1 and PC2 are subjected to a change of polarization state in an analogical way as in the case of polarization controllers PC1 and PC2 in the polarization attractor circuit A1 in FIG. 1 and thus the above mentioned signals are given orthogonal polarization states by performing horizontal polarization in the polarization controller PC1 and by performing vertical polarization in the polarization controller PC2. The signals having the wavelengths of 1550 nm and subjected to the change of polarization state are subsequently delivered from the outputs of polarization controllers PC1 and PC2 to the separate outputs of the polarization beam splitter PBS1 in which the signals are combined in such a way that polarization-multiplexed signals having the wavelengths of 1550 nm are obtained at the common output of the polarization beam splitter PBS1. Such combined signals get to the transmission medium 210 which, in this embodiment, is a transmission optical fibre via which the polarization-multiplexed signals having the wavelength of 1550 nm are sent to the input of a switching element F4 located in the second polarization circuit B2. In the polarization attractor circuit B2 the multiplexed signals having a wavelength of 1550 nm are subjected to the same operations as in the case of polarization attractor circuit A1 in FIG. 1 and the signals get to the respective outputs of the polarization attractor circuit B2 and from there to the end devices EDB2_1, EDB2_2.

[0120] The above description of presented exemplary embodiments has been provided to enable any person skilled in the art to carry out or use the present invention. It is also possible to modify these exemplary embodiments in various ways to include all such changes, modifications and variants that fall within the essence and scope of the attached patent claims. The basic principles defined herein may thus be applied in other embodiments not extending the scope of the invention. Therefore, the intention of the present invention is not to limit it to the exemplary embodiments presented herein but to make is consistent with the broadest possible scope corresponding to the principles and new features presented herein.

[0121] Thus, the present solution according to the invention uses the above specified technical means as indicated in FIG. 1 and FIG. 2 to offer a transmission method and system which use of the designed polarization attractor circuits and which are designed to increase the speed of data transmission via a transmission medium.

[0122] The invention is capable of being used in particular in all applications where there is a need for increasing transmission capability without interfering in the existing structures of a transmission system, in particular in server rooms. This does not exclude however the possibility of applying the solution according to the invention in other places where an increase in data transmission speed is required.