An optical switching device and method combining space division and wavelength division

Abstract

The present invention discloses an optical switching device and method combining space division and wavelength division, which includes a first-stage space-division optical switch combination, a second-stage switching unit, and a third-stage space-division optical switch combination. The second-stage switching unit is composed of four cyclic arrayed waveguide gratings. The input signal is output to the cyclic arrayed waveguide grating through the selection of the output port by the first optical switch, and the routing exchange is completed by using the cyclic feature of the cyclic arrayed waveguide grating and output through the corresponding second optical switch. In the present invention, when the number of switching ports is expanded, the second-stage switching unit remains four AWGs unchanged, reducing the number of required control units. Moreover, by using space-division optical switching, the optical path is switched by actively configuring the optical routing components, and by using wavelength-division optical switching, the working wavelength of the input signal is actively tuned, and combined with the wavelength routing characteristics of the cyclic arrayed waveguide grating, the active selection of the output port of the optical signal is performed, achieving strict non-blocking.

Description

Technical Field

[0001] The present invention relates to the technical field of optical switching, and particularly relates to an optical switching device and method combining space division and wavelength division. Background Art

[0002] Optical switching technology is used in fiber optic communication networks, internal switch networks in data centers, and internal interconnection networks of high-throughput computers to achieve low-power and high-throughput optical signal cross-connection.

[0003] Currently, the commonly used optical switching methods include space-division optical switching and wavelength-division optical switching. Space-division optical switching switches the optical path by actively configuring the optical routing elements, and wavelength-division optical switching actively tunes the working wavelength of the input signal and cooperates with the wavelength routing characteristics of the arrayed waveguide grating (AWG) to actively select the output port of the optical signal.

[0004] The expansion of the number of ports in an optical switching system has always been a hot topic pursued by the industry. The space-division optical switching method can be expanded to a relatively large number of switching ports, such as 128x128 or even 1024x1024. However, the number of switching units to be controlled increases sharply with the number of switching ports, posing great challenges to packaging and electrical control. The current maximum number of switching ports in the wavelength-division optical switching method is 32x32. If expansion is required, it poses a great challenge to the number of tunable wavelengths.

[0005] Currently, to increase the number of ports in an optical switching system, a three-stage AWG (arrayed waveguide grating)-SpaceSwitch (space-division optical switch)-AWG architecture can be used to achieve an optical switching system with a large number of ports. The strict non-blocking requirement of the optical switching system is an important requirement for optical signal routing. For the scheme using an optical switch system to implement the space-division optical switching method, the Benes-type topology scheme is usually adopted. However, this topology can only achieve rearrangeable non-blocking, and conflicts will occur between different lines. For example: Figure 1 As shown in the Benes 4x4 topology, when implementing the routing between ports 1-1 (the dotted line in the figure), the phase Δψ of the first row of optical switches is 0°, and the routing between ports 3-1 and 3-2 cannot be achieved.

[0006] In view of this, it is urgent to improve the existing optical switching device combining space division and wavelength division to reduce the number of switching units and achieve strict non-blocking routing. Summary of the Invention

[0007] Aiming at the above defects, the technical problem to be solved by the present invention is to provide an optical switching device and method combining space division and wavelength division to solve the problems of a large number of switching units in the prior art and the inability to achieve strict non-blocking routing.

[0008] To this end, an optical switching device combining space division and wavelength division provided by the present invention includes:

[0009] A first-stage space-division optical switch combination, which is composed of 4N first optical switches arranged in parallel, and 2N of the first optical switches form a group. The first optical switch is a 1×2 optical switch, and N is an even number greater than or equal to 2;

[0010] A second-stage switching unit, which is composed of four cyclic arrayed waveguide gratings and equally divided into two groups, corresponding to two groups of the first optical switches respectively. Each cyclic arrayed waveguide grating has 2N input ports and 2N output ports;

[0011] A third-stage space-division optical switch combination, which is composed of 4N second optical switches. The second optical switch is a 1×2 optical switch and is arranged in a mirror image corresponding to the first optical switch one by one;

[0012] 4N tunable harmonic input signals are equally divided into two groups. Each input signal consists of a set of 2N wavelengths of tunable harmonics. The 2N input signals are respectively input into a corresponding group of the first optical switches, and either the first output port is selected to output to one group of cyclic arrayed waveguide gratings, or the second output port is selected to output to the other group of cyclic arrayed waveguide gratings. The routing exchange is completed by using the cyclic characteristics of the cyclic arrayed waveguide gratings and output via the corresponding second optical switch.

[0013] In the above technical solution, preferably, the first-stage space-division optical switch combination is composed of 8 of the first optical switches, and the third-stage space-division optical switch combination is composed of 8 second optical switches.

[0014] In the above technical solution, preferably, before and after the cyclic arrayed waveguide grating completes the routing exchange, in the signal sets of each input port and the corresponding output port, the wavelength signal sorting is as follows:

[0015] First input port Corresponding first output port

[0016] Second input port Corresponding second output port

[0017] Third input port Corresponding third output port

[0018] Fourth input port Corresponding fourth output port

[0019] Among them, represents the (j + 1)-th wavelength in the i-th signal, where i is a natural number and j is an integer.

[0020] In the above technical solution, preferably, the value of N is 2, 4, 8 or 16.

[0021] The present invention also provides an optical switching method combining space division and wavelength division, including the following steps:

[0022] Generate 4N tunable harmonic input signals through a tunable laser and divide them into two groups equally. Each of the input signals consists of a set of tunable harmonics with 2N wavelengths. The 2N input signals are respectively input into a group of first optical switches in the first-stage space-division optical switch combination. The first-stage space-division optical switch combination is composed of 4N first optical switches arranged in parallel, and 2N of the first optical switches form a group. The first optical switch is a 1×2 optical switch, and N is an even number greater than or equal to 2;

[0023] The first optical switch selects a corresponding output port according to waveguide-level routing and outputs it into a group in the second-stage switching unit. The second-stage switching unit is composed of four circulatory arrayed waveguide gratings and is divided into two groups equally, corresponding to the two groups of first optical switches respectively. Each of the circulatory arrayed waveguide gratings has 2N input ports and 2N output ports;

[0024] The circulatory arrayed waveguide grating completes routing and switching by using the circulatory characteristics of the circulatory arrayed waveguide grating;

[0025] The output signal of the circulatory arrayed waveguide grating is output through the corresponding second optical switch in the third-stage space-division optical switch combination.

[0026] In the above technical solution, preferably, the first-stage space-division optical switch combination is composed of 8 of the first optical switches, and the third-stage space-division optical switch combination is composed of 8 second optical switches.

[0027] In the above technical solution, preferably, the value of N is 2, 4, 8 or 16.

[0028] In the above technical solution, preferably, before and after the circulatory arrayed waveguide grating completes routing and switching, in the signal sets of each input port and the corresponding output port, the wavelength signals are sorted as follows:

[0029] First input port Corresponding first output port

[0030] Second input port Corresponding second output port

[0031] Third input port Corresponding third output port

[0032] Fourth input port Corresponding fourth output port

[0033] Wherein, represents the (j + 1)-th wavelength in the i-th signal, where i is a natural number and j is an integer.

[0034] As can be seen from the above technical solution, the optical switching device and method combining space division and wavelength division provided by the present invention solve the problems of a large number of switching units in the prior art and the inability to achieve strict non-blocking routing. Compared with the prior art, the present invention has the following beneficial effects:

[0035] The second-stage switching unit is composed of four cyclic arrayed waveguide gratings. When the number of switching ports is expanded, the second-stage switching unit remains four AWGs unchanged, reducing the number of required control units.

[0036] By using space-division optical switching, the optical path is switched by actively configuring the optical routing elements. By using wavelength-division optical switching, the working wavelength of the input signal is actively tuned, and in combination with the wavelength routing characteristics of the cyclic arrayed waveguide grating, the output port of the optical signal is actively selected, thereby achieving strict non-blocking. Brief Description of the Drawings

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce and explain the drawings required for the description of the embodiments of the present invention or the prior art. Obviously, the drawings in the following description are only partial embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0038] Figure 1 It is a topology diagram of the prior art Benes 4x4;

[0039] Figure 2 It is a schematic diagram of an optical switching device combining space division and wavelength division provided by the present invention;

[0040] Figure 3 It is a schematic diagram of the output wavelength sequence configuration of the cyclic arrayed waveguide grating in the present invention. Detailed Embodiments

[0041] The following will clearly and completely describe the technical solutions of the embodiments of the present invention in conjunction with the drawings of the embodiments of the present invention. Obviously, the following described embodiments are only partial embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0042] In order to make a clearer explanation and illustration of the technical solution and implementation manner of the present invention, several preferred specific embodiments for implementing the technical solution of the present invention are introduced below.

[0043] It should be noted that the orientation terms such as "inside, outside", "front, back", and "left, right" in this article are expressed based on the product in the use state. Obviously, the use of the corresponding orientation terms does not limit the protection scope of the present solution.

[0044] The present invention provides an optical switching device and method combining space division and wavelength division, adopting a three-level architecture of space division optical switch - cyclic arrayed waveguide grating - space division optical switch (Space Switch - Cyclic AWG - Space Switch, SAS). By combining space division optical switching and wavelength division optical switching, large-port-number optical switching is achieved. Compared with other architectures, the second-level switching unit is maintained as four AWGs, greatly reducing the number of switching units, and being able to achieve strict non-blocking. When any two paths are routed, routing conflicts will not occur, and the remaining lines can all achieve routing.

[0045] Specifically, an optical switching device combining space division and wavelength division provided by the present invention is composed of a first-level space division optical switch combination, a second-level switching unit, and a third-level space division optical switch combination.

[0046] The first-level space division optical switch combination is composed of 4N first optical switches arranged in parallel, and 2N of the first optical switches form a group. The first optical switch is a 1×2 optical switch, and N is an even number greater than or equal to 2.

[0047] The second-level switching unit is composed of four cyclic arrayed waveguide gratings and is equally divided into two groups, corresponding to the two groups of the first optical switches respectively. Each cyclic arrayed waveguide grating has 2N input ports and 2N output ports.

[0048] The third-level space division optical switch combination is composed of 4N second optical switches. The second optical switch is a 1×2 optical switch and is arranged in a mirror image corresponding to the first optical switch one by one.

[0049] 4N tunable harmonic input signals are equally divided into two groups. Each input signal consists of a set of 2N wavelengths of tunable harmonics. The 2N input signals are respectively input into a corresponding group of the first optical switches, and either the first output port is selected to output to one group of the cyclic arrayed waveguide gratings, or the second output port is selected to output to the other group of the cyclic arrayed waveguide gratings. The routing exchange is completed by using the cyclic characteristics of the cyclic arrayed waveguide gratings and is output via the corresponding second optical switches.

[0050] Figure 2Schematic diagram of an embodiment of an optical switching device combining space division and wavelength division provided by the present invention. In this embodiment, the number of ports of the optical switching device is 8×8, that is, 8 input ports and 8 output ports. Obviously, the number of input and output ports can be set to more according to actual applications, such as 16×16, 32×32, 64×64, etc.

[0051] As Figure 2 shown in the embodiment, the optical switching device combining space division and wavelength division includes a first-stage space-division optical switch combination 10, a second-stage switching unit 20, and a third-stage space-division optical switch combination 30.

[0052] The first-stage space-division optical switch combination 10 is composed of 8 first optical switches, denoted as Switch_IN_1, Switch_IN_2,..., Switch_IN_8 respectively. The first optical switch adopts a 1×2 optical switch, which has one input port and two output ports. Among them, the input port of the first first optical switch Switch_IN_1 is defined as IN1_Switch_in_1, and the two output ports are IN1_Switch_out1 and IN1_Switch_out2 respectively. The input port of the second first optical switch Switch_IN_2 is IN2_Switch_in_1, and the two output ports are IN2_Switch_out1 and IN2_Switch_out2 respectively, and so on. The first-stage space-division optical switch combination 10 is used to select a corresponding output port to output the input signal by using the first optical switch. For example, select the 1_Switch_out1 or 1_Switch_out2 output port to output and enter the second-stage switching unit 20.

[0053] The second-stage switching unit 20 is composed of four cyclic arrayed waveguide gratings, denoted as AWG1, AWG2,..., AWG4 respectively. The second-stage switching unit 20 is configured in a 4×4 mode, that is, it has 4 input ports (awg_in_1, awg_in_2, awg_in_3, awg_in_4) and 4 output ports (awg_out_1, awg_out_2, awg_out_3, awg_out_4). The second-stage switching unit 20 is used to complete wavelength-level routing switching.

[0054] The third - level space - division optical switch combination consists of 8 second - level optical switches, denoted as Switch_OUT_1, Switch_OUT_2, ……, Switch_OUT_8 respectively. The second - level optical switch also uses a 1×2 optical switch, which has one input port and two output ports, and is configured to be used in a mirror relationship with the first - level optical switch. Each second - level optical switch corresponds to a first - level optical switch, and the output port of the second - level optical switch is used to receive signals, and the input port is used to output signals, that is, the second - level optical switch has two input ports and one output port. Among them, it is defined that: the first second - level optical switch Switch_OUT_1 has two input ports OUT1_Switch_in1, OUT1_Switch_in2 and one output port OUT1_Switch_out1, the second second - level optical switch Switch_OUT_2 has two input ports OUT2_Switch_in1, OUT2_Switch_in2 and one output port OUT2_Switch_out1, and so on.

[0055] Based on the above optical switching device that combines space - division and wavelength - division, 8 tunable signals are generated by a tunable laser as input signals, and are divided into two groups and respectively input into the first - level space - division optical switch combination 10. Among them, each input signal is a signal set composed of different wavelengths (λ1, λ2, λ3, λ4). The number of wavelengths in each input signal is equal to half of the number of ports of the optical switching device. In this embodiment, the number of ports of the optical switching device is 8, so the number of wavelengths in each input signal is 4, denoted as λ1, λ2, λ3, λ4.

[0056] The 8 tunable harmonic input signals are divided into two groups and respectively input into the input ports of 8 first - level optical switches in the first - level space - division optical switch combination 10, and according to the determined waveguide - layer routing, one corresponding output port of the corresponding first - level optical switch is selected for output.

[0057] For example: the first input signal is input from the IN1_Switch_in1 port of the first - level optical switch Switch_IN_1, and the IN1_Switch_out1 output port is selected for output, and enters the input port awg_in_1 of AWG1, and wavelength - division optical switching is completed in AWG1 to achieve wavelength - level routing.

[0058] According to the cyclic (Cyclic) property of the cyclic arrayed waveguide grating, the output wavelength signal sequence configuration is fixed, as Figure 3 shown, the output wavelength signal sequence configuration is as follows:

[0059] The first signal input from the awg_in_1 port of the AWG Configured in the order of the serial numbers of the output ports of the AWG, that is configured in awg_out_1, configured in awg_out_2, configured in awg_out_3, configured in awg_out_4.

[0060] The second signal input from the awg_in_2 port of the AWG According to the Cyclic property, circularly shifted forward by one bit in sequence After that, configured in the order of the serial numbers of the output ports of the AWG, that is configured in awg_out_1, configured in awg_out_2, configured in awg_out_3, configured in awg_out_4.

[0061] The third signal input from the awg_in_3 port of the AWG According to the Cyclic property, circularly shifted forward by two bits in sequence After that, configured in the order of the serial numbers of the output ports of the AWG, that is configured in awg_out_1, configured in awg_out_2, configured in awg_out_3, configured in awg_out_4.

[0062] The fourth signal input from the awg_in_4 port of the AWG According to the Cyclic property, circularly shifted forward by three bits in sequence After that, configured in the order of the serial numbers of the output ports of the AWG, that is configured in awg_out_1, configured in awg_out_2, configured in awg_out_3, configured in awg_out_4.

[0063] Thus, the corresponding relationship of the wavelength configuration order of each input and output port of the AWG is as follows:

[0064] The first input port The corresponding first output port

[0065] The second input port The corresponding second output port

[0066] Third input port Corresponding third output port

[0067] Fourth input port Corresponding fourth output port

[0068] Wherein, represents the (j + 1)-th wavelength in the i-th signal, where i is a natural number and j is an integer.

[0069] Based on the cyclic property of the above integrated looped array waveguide grating, the sequential configuration of the output wavelength signals is as follows:

[0070] Each wavelength signal in the M-th input signal is cyclically shifted forward by M - 1 bits in sequence and configured according to the input port number sequence of the integrated looped array waveguide grating, where M is an integer greater than or equal to 1.

[0071] In the above embodiments, if the input signal is output from the output port awg_out_1 of AWG1, enters the second optical switch, and is output from the OUT1_Switch_out1 port of the second optical switch Switch_OUT_1, then the routing between Switch_IN_1 and Switch_OUT_1 is achieved. If the input signal is output from the output port awg_out_2 of AWG1, enters the second optical switch Switch_OUT_2, and is output from the OUT2_Switch_out1 port of the second optical switch Switch_OUT_2, then the routing between Switch_IN_1 and Switch_OUT_2 is achieved.

[0072] Similarly, if the input signal undergoes space-division optical switching and is output from the out2 ports of Switch_IN_1, Switch_IN_2, Switch_IN_3, and Switch_IN_4, then it enters AWG3, and after wavelength-division optical switching, it is sequentially output to Switch_OUT_5, Switch_OUT_6, Switch_OUT_7, and Switch_OUT_7 to achieve routing switching.

[0073] The 5th - 8th input signals enter the first - stage optical switch combination. After space - division optical switching, they are output from the out1 port of the first optical switch and enter AWG2. After wavelength - division optical switching, they are sequentially output to the OUT_Switch_in1 ports of Switch_OUT_1, Switch_OUT_2, Switch_OUT_3, and Switch_OUT_4. If they are output from the out2 port of the first optical switch, they enter AWG4. After wavelength - division optical switching, they are sequentially output to the OUT_Switch_in2 ports of Switch_OUT_5, Switch_OUT_6, Switch_OUT_7, and Switch_OUT_7, achieving routing switching.

[0074] Based on the above optical switching device combining space - division and wavelength - division, the present invention also provides an optical switching method combining space - division and wavelength - division, including the following steps:

[0075] Generate 4N tunable harmonic input signals through a tunable laser and divide them into two groups equally. Each of the input signals consists of a set of 2N - wavelength tunable harmonics. The 2N input signals are respectively input into a group of first optical switches in the first - stage space - division optical switch combination. The first - stage space - division optical switch combination is composed of 4N first optical switches arranged in parallel, and 2N of the first optical switches form a group. The first optical switch is a 1×2 optical switch, and N is an even number greater than or equal to 2.

[0076] The first optical switch selects a corresponding output port according to waveguide - level routing and outputs it into a group in the second - stage switching unit. The second - stage switching unit is composed of four cyclic arrayed waveguide gratings and is divided into two groups equally, corresponding to the two groups of first optical switches respectively. Each of the cyclic arrayed waveguide gratings has 2N input ports and 2N output ports.

[0077] The cyclic arrayed waveguide grating completes routing switching by using the cyclic characteristics of the cyclic arrayed waveguide grating.

[0078] The output signals of the cyclic arrayed waveguide grating are output via the corresponding second optical switches in the third - stage space - division optical switch combination.

[0079] Based on the description of the above specific embodiments, the optical switching device and method combining space - division and wavelength - division provided by the present invention have the following advantages compared with the prior art:

[0080] First, the first- and second-stage switching units are composed of four Cyclic Arrayed Waveguide Gratings (Cyclic-AWGs). By using Cyclic-AWGs to replace a large number of optical switches, a large-scale optical port number optical switching device is formed. In the second stage, by expanding the number of ports of the Cyclic-AWG, the expansion of the port number of the optical switching system can be achieved, such as 16×16, 32×32, 64×64. Compared with using space-division optical switching, the problem that the number of switching units increases sharply with the number of switching ports is solved. There are only 4 Cyclic-λWGs in the second-stage switching unit. While expanding the port number, the number of switching units is controlled, reducing the pressure of packaging and electrical control.

[0081] Second, through the active tuning of the operating wavelength of the input signal and in cooperation with the wavelength routing characteristics of the Cyclic Arrayed Waveguide Grating (Cyclic-AWG), the active selection of the output port of the optical signal is carried out to achieve strict non-blocking. No conflicts will occur during the transmission of multiple groups of signals, enabling the meaningful transmission of multiple groups of signals. The number of optical switch devices is greatly reduced, and the link model is simplified.

[0082] Finally, it should also be noted that the terms "including", "comprising" or any other variants thereof used in this text are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. Without further limitations, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0083] The present invention is not limited to the above best implementation manner. Anyone should know that structural changes made under the inspiration of the present invention, as long as they have the same or similar technical solutions as the present invention, fall within the protection scope of the present invention.

Claims

1. An optical switching device combining space division and wavelength division, characterized in that, Comprising: A first - stage optical space - division switch combination, which is composed of 4N first optical switches arranged in parallel, and 2N of the first optical switches form a group. The first optical switch is a 1×2 optical switch, and N is an even number greater than or equal to 2. A second - stage switching unit, which is composed of four cyclic arrayed waveguide gratings and is equally divided into two groups, corresponding to two groups of the first optical switches respectively. Each cyclic arrayed waveguide grating has 2N input ports and 2N output ports. A third - stage optical space - division switch combination, which is composed of 4N second optical switches. The second optical switch is a 1×2 optical switch and is arranged in a mirror - image correspondence with the first optical switch one by one. 4N tunable harmonic input signals are equally divided into two groups. Each input signal consists of a set of 2N - wavelength tunable harmonics. The 2N input signals are respectively input into a corresponding group of the first optical switches, and either the first output port is selected to output to one group of the cyclic arrayed waveguide gratings, or the second output port is selected to output to the other group of the cyclic arrayed waveguide gratings. The routing exchange is completed by using the cyclic characteristics of the cyclic arrayed waveguide gratings and is output via the corresponding second optical switch. The sequential configuration mode of the output wavelength signals is: in the M - th input signal, each wavelength signal is cyclically shifted forward by M - 1 bits in sequence and is configured according to the input - port serial - number sequence of the cyclic arrayed waveguide grating, where M is an integer greater than or equal to 1.

2. The optical switching device combining space division and wavelength division according to claim 1, wherein The first - stage optical space - division switch combination is composed of 8 of the first optical switches, and the third - stage optical space - division switch combination is composed of 8 second optical switches.

3. The optical switching device combining space division and wavelength division according to claim 2, characterized in that Before and after the cyclic arrayed waveguide grating completes the routing exchange, in the signal sets of each input port and the corresponding output port, the wavelength - signal sorting is as follows: First input port , corresponding first output port ; Second input port , corresponding second output port ; Third input port , corresponding third output port ; Fourth input port , corresponding fourth output port ; Among them, represents the (j + 1)-th wavelength in the i-th signal, where i is a natural number and j is an integer.

4. The optical switching device combining space division and wavelength division according to claim 1, characterized in that The value of N is 2, 4, 8 or 16.

5. An optical switching method combining space division and wavelength division, characterized in that, Including the following steps: Generating 4N tunable harmonic input signals through a tunable laser and equally dividing them into two groups. Each input signal consists of a set of 2N - wavelength tunable harmonics. The 2N input signals are respectively input into a group of the first optical switches in the first - stage optical space - division switch combination. The first - stage optical space - division switch combination is composed of 4N first optical switches arranged in parallel, and 2N of the first optical switches form a group. The first optical switch is a 1×2 optical switch, and N is an even number greater than or equal to 2. The first optical switch selects a corresponding output port according to the waveguide - layer routing and outputs it into one group in the second - stage switching unit. The second - stage switching unit is composed of four cyclic arrayed waveguide gratings and is equally divided into two groups, corresponding to two groups of the first optical switches respectively. Each cyclic arrayed waveguide grating has 2N input ports and 2N output ports. The cyclic arrayed waveguide grating completes the routing exchange by using the cyclic characteristics of the cyclic arrayed waveguide grating. The sequential configuration mode of the output wavelength signals is: in the M - th input signal, each wavelength signal is cyclically shifted forward by M - 1 bits in sequence and is configured according to the input - port serial - number sequence of the cyclic arrayed waveguide grating, where M is an integer greater than or equal to 1. The output signal of the cyclic arrayed waveguide grating is output via the corresponding second optical switch in the third - stage optical space - division switch combination.

6. The optical switching method combining space division and wavelength division according to claim 5, characterized in that The first-stage optical space switch combination is composed of 8 of the first optical switches, and the third-stage optical space switch combination is composed of 8 of the second optical switches.

7. The optical switching method combining space division and wavelength division according to claim 5, characterized in that The value of N is 2, 4, 8 or 16.

8. The optical switching method combining space division and wavelength division according to claim 6, characterized in that Before and after the cyclic arrayed waveguide grating completes routing and switching, in the signal sets of each input port and the corresponding output port, the wavelength signal sorting is as follows: First input port , corresponding first output port ; Second input port , corresponding second output port ; Third input port , corresponding third output port ; Fourth input port , corresponding fourth output port ; Among them, represents the (j + 1)-th wavelength in the i-th signal, where i is a natural number and j is an integer.

Images