Photonics integrated multi-wavelength coherent transmitter and method of transmission

Abstract

The application relates to the field of optical communication and discloses a photonic integrated multi-wavelength coherent transmitter and a transmitting method, which comprises a multi-wavelength light source, a transmitter modulation module and an optical amplifier; the transmitter modulation module comprises a total beam splitter, a first micro-ring modulation sub-module, a second micro-ring modulation sub-module, a polarization rotator and a polarization light combiner; the total beam splitter divides the light wave generated by the multi-wavelength light source into a first light wave and a second light wave, and respectively sends the first light wave and the second light wave to the first micro-ring modulation sub-module and the second micro-ring modulation sub-module for modulation to obtain a first optical signal and a second optical signal; the polarization rotator performs polarization rotation on the second optical signal; and the polarization light combiner couples the first optical signal and the polarization-rotated second optical signal to obtain a composite optical signal which is amplified by the optical amplifier and then transmitted. Compared with the existing Mach-Zehnder modulator-based coherent transmitter, the application can improve the integration level by reducing the number of modulators.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical communication technology, and particularly relates to a photonic integrated multi-wavelength coherent transmitter and a transmitting method. BACKGROUND

[0002] At present, with the rapid development of emerging technologies such as artificial intelligence (AI), Internet of Things, 5G, etc., the demand of users for Internet traffic is rapidly increasing, which means that there is an urgent need for high integration, low power consumption and high transmission capacity in the development of optical fiber communication technology.

[0003] A coherent optical communication system can achieve a higher transmission rate by using a coherent modulation technology. The coherent transmitter designed based on this technology also has the advantage of high transmission sensitivity. However, when the system contains multiple wavelength signal lights, the coherent transmitter needs multiple modulators to modulate each wavelength, which causes the overall size of the coherent transmitter to increase exponentially, thereby affecting the integration of the coherent optical transceiver system.

[0004] The above content is only used to assist in understanding the technical solutions of the present application and does not represent an acknowledgement of the above content as related art. SUMMARY

[0005] The main purpose of the present application is to provide a photonic integrated multi-wavelength coherent transmitter and a transmitting method, which aims to solve the technical problem that the existing coherent transmitter needs to use multiple modulators for modulation when transmitting signal light containing multiple wavelengths, which causes the device size of the transmitter to increase exponentially, affecting the integration of the coherent optical communication system.

[0006] To achieve the above purpose, the present application provides a photonic integrated multi-wavelength coherent transmitter, which comprises:

[0007] a multi-wavelength light source, a transmitter modulation module and an optical amplifier;

[0008] The transmitter modulation module comprises a total beam splitter, a first micro-ring modulation sub-module, a second micro-ring modulation sub-module, a polarization rotator and a polarization light combiner;

[0009] The total beam splitter is connected with the multi-wavelength light source, the first micro-ring modulation sub-module and the second micro-ring modulation sub-module respectively, the second micro-ring modulation sub-module is connected with the polarization rotator in series and connected with the first micro-ring modulation sub-module in parallel, the first micro-ring modulation sub-module is further connected with the polarization light combiner, and the polarization light combiner is further connected with the optical amplifier;

[0010] The multi-wavelength light source is used for generating light waves of a preset number of wavelengths and sending the light waves to the total beam splitter;

[0011] The total beam splitter is configured to divide the light wave into a first light wave and a second light wave, and transmit the first light wave to the first micro-ring modulation submodule and transmit the second light wave to the second micro-ring modulation submodule.

[0012] The first micro-ring modulation submodule is configured to differentially modulate the first light wave based on the preset number of wavelengths to obtain a first optical signal, and transmit the first optical signal to the polarization light combiner.

[0013] The second micro-ring modulation submodule is configured to differentially modulate the second light wave based on the preset number of wavelengths to obtain a second optical signal, and transmit the second optical signal to the polarization rotator.

[0014] The polarization rotator is configured to perform polarization rotation on the second optical signal, and transmit the polarization-rotated second optical signal to the polarization light combiner.

[0015] The polarization light combiner is configured to couple the first optical signal and the polarization-rotated second optical signal to obtain a composite optical signal, and transmit the composite optical signal to the optical amplifier.

[0016] The optical amplifier is configured to amplify and emit the composite optical signal.

[0017] Optionally, the first micro-ring modulation submodule and the second micro-ring modulation submodule have the same structure; the first micro-ring modulation submodule comprises a first beam splitter, a first I-path micro-ring modulation unit, a first Q-path micro-ring modulation unit, a first phase shifter, and a first combiner.

[0018] The first beam splitter is connected to the total beam splitter, the first I-path micro-ring modulation unit, and the first Q-path micro-ring modulation unit, respectively; the first Q-path micro-ring modulation unit and the first phase shifter are connected in series and then connected in parallel to the first I-path micro-ring modulation unit; the first I-path micro-ring modulation unit is further connected to the first combiner; and the first combiner is further connected to the polarization light combiner.

[0019] The first beam splitter is configured to divide the first light wave into an I-path light wave and a Q-path light wave, and transmit the I-path light wave to the first I-path micro-ring modulation unit and transmit the Q-path light wave to the first Q-path micro-ring modulation unit.

[0020] The first I-path micro-ring modulation unit is configured to differentially modulate the I-path light wave based on the preset number of wavelengths of micro-rings to obtain an I-path optical signal, and transmit the I-path optical signal to the first combiner.

[0021] The first Q-path micro-ring modulation sub-module is configured to perform differential modulation on the Q-path light wave based on the preset number of micro-rings to obtain a Q-path optical signal, and send the Q-path optical signal to the first phase shifter.

[0022] The first phase shifter is configured to perform phase adjustment on the Q-path optical signal, and send the adjusted Q-path optical signal to the first combiner.

[0023] The first combiner is configured to perform signal synthesis on the I-path optical signal and the Q-path optical signal to obtain a first optical signal, and send the first optical signal to the polarization optical combiner.

[0024] Optionally, the first I-path micro-ring modulation unit and the first Q-path micro-ring modulation unit have the same structure, and the first I-path micro-ring modulation unit comprises a first I-path beam splitter, a first I-path upper micro-ring modulation assembly, a first I-path lower micro-ring modulation assembly, a first I-path phase shifter and a first I-path combiner.

[0025] The first I-path beam splitter is connected with the first beam splitter, the first I-path upper micro-ring modulation assembly and the first I-path lower micro-ring modulation assembly respectively, the first I-path lower micro-ring modulation assembly is connected with the first I-path phase shifter in series and then connected with the first I-path upper micro-ring modulation assembly in parallel, the first I-path upper micro-ring modulation assembly is further connected with the first I-path combiner, and the first I-path combiner is further connected with the first combiner.

[0026] The first I-path beam splitter is configured to divide the I-path light wave into a first I-path upper light wave and a first I-path lower light wave, and send the first I-path upper light wave to the first I-path upper micro-ring modulation assembly and send the first I-path lower light wave to the first I-path lower micro-ring modulation assembly.

[0027] The first I-path upper micro-ring modulation assembly is configured to perform first modulation on the first I-path upper light wave to obtain a first I-path upper optical signal, and send the first I-path upper optical signal to the first I-path combiner.

[0028] The first I-path lower micro-ring modulation assembly is configured to perform second modulation on the first I-path lower light wave to obtain a first I-path lower optical signal, and send the first I-path lower optical signal to the first I-path phase shifter.

[0029] The first modulation and the second modulation constitute differential modulation on the I-path light wave.

[0030] The first I-path phase shifter is configured to perform phase adjustment on the first I-path lower optical signal, and send the adjusted first I-path lower optical signal to the first I-path combiner.

[0031] The first I-path combiner is configured to perform signal light interference and synthesis of the first I-path uplink optical signal and the first I-path downlink optical signal to obtain an I-path optical signal, and send the I-path optical signal to the first combiner.

[0032] Optionally, the first I-path uplink micro-ring modulation component comprises a first I-path uplink micro-ring modulator array and a first I-path uplink driver array; and the first I-path downlink micro-ring modulation component comprises a first I-path downlink micro-ring modulator array and a first I-path downlink driver array.

[0033] The first I-path uplink micro-ring modulator array and the first I-path downlink micro-ring modulator array have the same structure; and each driver in the first I-path uplink driver array and each driver in the first I-path downlink driver array correspond to each other in an upper-lower arm complementary manner.

[0034] Optionally, the first I-path uplink micro-ring modulator array is configured to, when receiving the first I-path uplink optical wave, filter and modulate the first I-path uplink optical wave based on each micro-ring, wherein a resonant wavelength of each micro-ring corresponds to a wavelength of the multi-wavelength light source.

[0035] The first I-path uplink driver array is configured to load a driving signal and send the driving signal to the first I-path uplink micro-ring modulator array.

[0036] The first I-path uplink micro-ring modulator array is further configured to, based on each micro-ring, perform micro-ring modulation on the first I-path uplink optical wave according to the driving signal to obtain a first I-path uplink optical signal.

[0037] Optionally, the first I-path uplink micro-ring modulator array comprises a heater array, a micro-ring structure, and an electrode array.

[0038] The heater array is configured to adjust resonant wavelengths of each micro-ring of the preset number of wavelengths by power adjustment, so that the resonant wavelengths of each micro-ring correspond to the wavelengths of the multi-wavelength light source.

[0039] The electrode array is configured to receive the driving signal loaded by the driver array and send the driving signal to the micro-ring structure.

[0040] The micro-ring structure is configured to perform micro-ring modulation on the first I-path uplink optical wave by the driving signal to obtain a first I-path uplink optical signal.

[0041] Optionally, the first I-path uplink micro-ring modulation component further comprises an incoming waveguide and an outgoing waveguide.

[0042] The micro-ring structure comprises a micro-ring structure input end, a micro-ring straight waveguide, a micro-ring structure output end, and a preset number of micro-rings.

[0043] Each heater in the heater array, each signal loading electrode pair in the electrode array and each micro-ring correspond to each other respectively;

[0044] The micro-ring structure input end is used for receiving the first I uplink optical wave transmitted by the incoming waveguide and transmitting the first I uplink optical wave to the micro-ring straight waveguide, and sending the driving signal to the preset number of micro-rings through each signal loading electrode pair, so as to obtain a first I uplink optical signal by micro-ring modulation of the first I uplink optical wave based on each micro-ring according to the driving signal.

[0045] The micro-ring straight waveguide is further used for transmitting the obtained first I uplink optical signal to the outgoing waveguide based on the micro-ring structure output end when each micro-ring completes modulation of the first I uplink optical wave through the driving signal.

[0046] In addition, in order to achieve the above-mentioned purpose, the application further provides a photonic integrated multi-wavelength coherent transmitter based on the above-mentioned photonic integrated multi-wavelength coherent transmitter, and the method comprises the following steps:

[0047] Obtaining optical waves of a preset wavelength number, and the optical waves are first optical waves and second optical waves;

[0048] According to the preset wavelength number, the first optical wave and the second optical wave are respectively micro-ring modulated to obtain first optical signals and second optical signals;

[0049] The second optical signal is polarization rotated;

[0050] The first optical signal and the polarization-rotated second optical signal are coupled to obtain a polarization composite optical signal, and the polarization composite optical signal is amplified and emitted.

[0051] Optionally, the first optical wave and the second optical wave are respectively micro-ring modulated according to the preset wavelength number to obtain first optical signals and second optical signals, which comprises:

[0052] When the first / second optical wave is obtained, the first / second optical wave is divided into I path optical waves and Q path optical waves;

[0053] The I path optical wave and the Q path optical wave are respectively differentially modulated based on the micro-ring of the preset wavelength number to obtain I path optical signals and Q path optical signals;

[0054] The Q path optical signal is phase adjusted;

[0055] The I path optical signal and the phase-adjusted Q path optical signal are synthesized to obtain the first / second optical signal.

[0056] Optionally, the differential modulation of the I-path light wave and the Q-path light wave based on the preset number of micro rings respectively obtains an I-path light signal and a Q-path light signal, comprising:

[0057] In the process of obtaining the I / Q-path light wave, the I / Q-path light wave is divided into an uplink light wave and a downlink light wave;

[0058] The uplink light wave and the downlink light wave are modulated based on the preset number of micro rings to obtain an uplink light signal and a downlink light signal;

[0059] The downlink light signal is phase adjusted;

[0060] The uplink light signal and the phase-adjusted downlink light signal are synthesized to obtain an I / Q-path light signal.

[0061] The application provides a photonic integrated multi-wavelength coherent transmitter and a transmitting method, the photonic integrated multi-wavelength coherent transmitter comprising a multi-wavelength light source, a transmitter modulation module and an optical amplifier; the transmitter modulation module comprises a total beam splitter, a first micro ring modulation submodule, a second micro ring modulation submodule, a polarization rotator and a polarization light combiner; wherein the total beam splitter is connected with the multi-wavelength light source, the first micro ring modulation submodule and the second micro ring modulation submodule respectively, the second micro ring modulation submodule is connected with the first micro ring modulation submodule in parallel after being connected with the polarization rotator in series, the first micro ring modulation submodule is further connected with the polarization light combiner, and the polarization light combiner is further connected with the optical amplifier; since the first micro ring modulation submodule and the second micro ring modulation submodule receive first light waves and second light waves respectively in the application, the micro ring modulation of a preset number of light waves can be realized to obtain first signal light and second signal light, the second light signal after polarization rotation is coupled with the first signal light to obtain a composite signal light for amplification and emission, the coherent modulation of the light waves is realized while reducing the size of the chip, and compared with the existing coherent transmitter based on a Mach-Zehnder modulator, the integration level can be improved by reducing the number of modulators. BRIEF DESCRIPTION OF DRAWINGS

[0062] Figure 1 It is a structural block diagram of the first embodiment of the photonic integrated multi-wavelength coherent transmitter of the application;

[0063] Figure 2 It is a structural block diagram of the second embodiment of the photonic integrated multi-wavelength coherent transmitter of the application;

[0064] Figure 3 It is a structural block diagram of the third embodiment of the photonic integrated multi-wavelength coherent transmitter of the application;

[0065] Figure 4Structure diagram of the first I-path micro-ring modulation unit in the third embodiment of the photonically integrated multi-wavelength coherent transmitter of the present application;

[0066] Figure 5 Structure diagram of the photonically integrated multi-wavelength coherent transmitter of the present application;

[0067] Figure 6 Structure diagram of the I-path micro-ring modulator array in the third embodiment of the photonically integrated multi-wavelength coherent transmitter of the present application;

[0068] Figure 7 Structure diagram of the optical transceiver system comprising the photonically integrated multi-wavelength coherent transmitter of the present application;

[0069] Figure 8 Structure diagram of the optical transceiver system comprising the photonically integrated multi-wavelength coherent transmitter of the present application;

[0070] Figure 9 Another structure diagram of the optical transceiver system comprising the photonically integrated multi-wavelength coherent transmitter of the present application;

[0071] Figure 10 Structure diagram of the single-polarization optical transceiver system based on the photonically integrated multi-wavelength coherent transmitter of the present application;

[0072] Figure 11 Flow diagram of the first embodiment of the photonically integrated multi-wavelength coherent transmission method of the present application;

[0073] Figure 12 Flow diagram of the micro-ring modulation step for the first / second optical wave in the photonically integrated multi-wavelength coherent transmission method of the present application;

[0074] Figure 13 Flow diagram of the micro-ring modulation step for the I / Q-path optical wave in the photonically integrated multi-wavelength coherent transmission method of the present application;

[0075] Figure 14 Full flow diagram of the photonically integrated multi-wavelength coherent transmission method of the present application.

[0076] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0077] It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

[0078] The technical solutions of the present application will be described clearly and completely below in connection with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0079] It should be noted that the description of "first", "second" and the like in the embodiments of the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features, and the technical solutions of each embodiment can be combined with each other, but it must be based on the fact that the technical solutions can be realized by those skilled in the art. When the combination of technical solutions contradicts each other or cannot be realized, it should be considered that the combination of technical solutions does not exist and is not within the scope of protection required by the present application.

[0080] Referring to Figure 1 , Figure 1 The structure block diagram of the first embodiment of the photonic integrated multi-wavelength coherent transmitter of the present application is shown in the figure.

[0081] As Figure 1 shown, in the embodiment, the photonic integrated multi-wavelength coherent transmitter comprises a multi-wavelength light source 1, a transmitter modulation module 2 and an optical amplifier 3.

[0082] The transmitter modulation module 2 comprises a beam splitter 21, a first micro-ring modulation sub-module 22, a second micro-ring modulation sub-module 22', a polarization rotator 23 and a polarization beam combiner 24.

[0083] The beam splitter 21 is connected with the multi-wavelength light source 1, the first micro-ring modulation sub-module 22 and the second micro-ring modulation sub-module 22' respectively. The second micro-ring modulation sub-module 22' is connected with the first micro-ring modulation sub-module 22 in parallel after being connected with the polarization rotator 23 in series. The first micro-ring modulation sub-module 22 is further connected with the polarization beam combiner 24. The polarization beam combiner 24 is further connected with the optical amplifier 3.

[0084] It should be noted that the above-mentioned photonic integrated multi-wavelength coherent transmitter provided by the embodiment can be integrated based on a silicon-based platform, can be applied in the field of optical communication, and can be specifically applied in a scene of modulating multi-wavelength light waves, such as polarization multiplexing, quadrature phase shift keying (QPSK), quadrature amplitude modulation (QAM), and the like, and of course can also be in other scenes of modulating and transmitting light waves with multiple wavelengths, and the embodiment is not limited in particular.

[0085] The multi-wavelength light source 1 is configured to generate light waves of a preset wavelength number and send the light waves to the total beam splitter 21.

[0086] It should be noted that the multi-wavelength light source 1 can be composed of N wavelengths with consistent intervals, where N is a positive integer not less than two, and N is the preset wavelength number. The multi-wavelength light source can be a single optical frequency comb laser capable of emitting N wavelengths, can be a multi-wavelength laser containing N wavelengths, or can be an array of single-wavelength lasers corresponding to N wavelengths.

[0087] The total beam splitter 21 is configured to divide the light waves into first light waves and second light waves, and send the first light waves to the first micro-ring modulation submodule 22 and the second light waves to the second micro-ring modulation submodule 22'.

[0088] It should be understood that the total beam splitter 21 can be a beam splitter that divides the light waves into two after receiving each wavelength light sent by the multi-wavelength light source 1. Specifically, the total beam splitter 21 can divide the light waves into two light waves, i.e., the first light waves and the second light waves. For ease of understanding, the first light waves can be regarded as Ex light waves, and the second light waves can be regarded as Ey light waves, at this time, the two light waves have the same polarization state (for example, the first polarization state TE).

[0089] The first micro-ring modulation submodule 22 is configured to differentially modulate the first light waves based on the preset wavelength number, obtain first optical signals, and send the first optical signals to the polarization beam combiner 24.

[0090] The second micro-ring modulation submodule 22' is configured to differentially modulate the second light waves based on the preset wavelength number, obtain second optical signals, and send the second optical signals to the polarization rotation module 4.

[0091] It can be understood that the first micro-ring modulation sub-module 22 and the second micro-ring modulation sub-module 22' can adopt the same or similar structure containing micro-rings, and based on the structure, the optical waves of a preset number of wavelengths can be micro-ring modulated. The resonance wavelengths of each micro-ring used for modulation can correspond to the wavelengths of each optical wave of the multi-wavelength light source respectively.

[0092] It should be noted that since the first optical signal and the second optical signal obtained by the first micro-ring modulation sub-module 22 and the second micro-ring modulation sub-module 22' respectively have the same polarization state, for example, the first polarization state TE, in order to realize the conversion of the two optical signals to different polarization states to realize polarization multiplexing, the second optical signal can be input to the polarization rotator 23 to realize the conversion of the polarization state of the second optical signal.

[0093] The polarization rotator 23 is configured to perform polarization rotation on the second optical signal and send the second optical signal after polarization rotation to the polarization beam combiner 24.

[0094] It can be understood that the polarization rotator (PR) is an optical device for changing the polarization state of light, and the second optical signal after polarization rotation by the polarization rotator 23 can be converted to the second polarization state TM orthogonal to the first polarization state TE, and then the second optical signal with the second polarization state TM is sent to the polarization beam combiner 24.

[0095] The polarization beam combiner 24 is configured to couple the first optical signal and the second optical signal after polarization rotation to obtain a composite optical signal, and send the composite optical signal to the optical amplifier 3.

[0096] It can be understood that when the first optical signal (E TE ) with the first polarization state TE and the second optical signal (E TM ) with the second polarization state TM are received, the two optical signals with different polarization states can be coupled by the polarization beam combiner (PBC) to obtain a polarization composite optical signal.

[0097] The optical amplifier 3 is configured to amplify and emit the composite optical signal.

[0098] It should be noted that the optical amplifier 3 can amplify the polarization composite optical signal obtained by coupling before output, which can enhance the optical power of the output signal and realize better anti-interference performance.

[0099] This embodiment uses a first micro-ring modulation submodule and a second micro-ring modulation submodule to receive the first and second light waves emitted by a multi-wavelength light source after being split by a beam splitter. It can perform micro-ring modulation on a preset number of light waves to obtain a first optical signal and a second optical signal. The second optical signal, after polarization rotation, is coupled with the first optical signal to obtain a composite optical signal, which is then amplified and emitted. This reduces the chip size while achieving coherent modulation of light waves. Compared with existing coherent optical transmitters that require multiple Mach-Zehnder modulators to modulate multi-wavelength light waves, the photonic integrated multi-wavelength coherent transmitter in this embodiment can improve the integration level by reducing the number of modulators.

[0100] refer to Figure 2 , Figure 2 This is a structural block diagram of a second embodiment of the photonic integrated multi-wavelength coherent transmitter of the present invention.

[0101] Furthermore, the first optical wave (Ex path optical wave) and the second optical wave (Ey path optical wave) can be two optical waves obtained by splitting the beam in two by the beam splitter. The first and second optical waves are respectively modulated using in-phase and quadrature (IQ) modulation, such as... Figure 2 As shown, in this embodiment, the first micro-ring modulation submodule 22 and the second micro-ring modulation submodule 22' have the same structure.

[0102] The first micro-ring modulation submodule 22 includes a first beam splitter 221, a first I-channel micro-ring modulation unit 222, a first Q-channel micro-ring modulation unit 223, a first phase shifter 224, and a first beam combiner 225.

[0103] The first beam splitter 221 is connected to the main beam splitter 21, the first I-channel micro-ring modulation unit 222, and the first Q-channel micro-ring modulation unit 223. The first Q-channel micro-ring modulation unit 223 and the first phase shifter 224 are connected in series and then connected in parallel with the first I-channel micro-ring modulation unit 222. The first I-channel micro-ring modulation unit 222 is also connected to the first beam combiner 225. The first beam combiner 225 is also connected to the polarization beam combiner 24.

[0104] exist Figure 2 In the second micro-ring modulation submodule 22', there are a second beam splitter 221', a second I-channel micro-ring modulation unit 222', a second Q-channel micro-ring modulation unit 223', a second phase shifter 224', and a second beam combiner 225'.

[0105] The second beam splitter 221' is connected with the total beam splitter 21', the second I-path micro-ring modulation unit 222', the second Q-path micro-ring modulation unit 223' respectively, the second Q-path micro-ring modulation unit 223' and the second phase shifter 224' are connected in series and then connected in parallel with the second I-path micro-ring modulation unit 222', the second I-path micro-ring modulation unit 222' is further connected with the second beam combiner 225', and the second beam combiner 225' is further connected with the polarization rotator 23'.

[0106] The following describes the modulation process of the first micro-ring modulation sub-module 22 on the first light wave (Ex-path light wave), and the modulation process of the second micro-ring modulation sub-module 22' on the second light wave (Ey-path light wave) is not described here.

[0107] The first beam splitter 221 is configured to divide the first light wave into an I-path light wave and a Q-path light wave, and send the I-path light wave to the first I-path micro-ring modulation unit and send the Q-path light wave to the first Q-path micro-ring modulation unit.

[0108] It can be understood that, for the convenience of distinction, the modulated light signal of the I-path light wave can be represented as Ex-I (I-path light signal), and the modulated light signal of the Q-path light wave can be represented as Ex-Q (Q-path light signal).

[0109] The first I-path micro-ring modulation unit 222 is configured to perform differential modulation on the I-path light wave based on the preset number of micro-rings to obtain an I-path light signal, and send the I-path light signal to the first beam combiner 225.

[0110] The first Q-path micro-ring modulation unit 223 is configured to perform differential modulation on the Q-path light wave based on the preset number of micro-rings to obtain a Q-path light signal, and send the Q-path light signal to the first phase shifter 224.

[0111] The first phase shifter 224 is configured to perform phase adjustment on the Q-path light signal and send the adjusted Q-path light signal to the first beam combiner 225.

[0112] It should be noted that, in order to realize IQ modulation, the Q-path light signal can be input to the first phase shifter 224 for phase adjustment. Specifically, the Q-path light signal can be phase-shifted by 90° to realize a 90° phase difference between the two light signals, and the phase-shifted Q-path light signal is input to the first beam combiner 225.

[0113] The first beam combiner 225 is configured to perform signal synthesis on the I-path light signal and the Q-path light signal to obtain a first light signal, and send the first light signal to the polarization beam combiner 24.

[0114] In a specific implementation, the first beam combiner 225 can combine Ex-I and Ex-Q to obtain the optical signal of Ex path, i.e., the first optical signal, and send the first optical signal to the polarization beam combiner 24.

[0115] It should also be noted that in the second micro-ring modulation submodule 22', the second beam combiner 225' can combine Ey-I and Ey-Q to obtain the optical signal of the Ey path, i.e., the second optical signal, and send the second optical signal to the polarization rotator 23 for polarization adjustment.

[0116] It is understandable that in the first micro-ring modulation submodule 22, when receiving the (Ex-I) optical signal and the (Ex-Q) optical signal with a 90-degree phase difference, they can be combined to obtain the first optical signal E of the Ex path. TE The signal is sent to the polarization beam combiner 24. Similarly, in the second micro-ring modulation submodule 22', when Ey-I and Ey-Q with a 90-degree phase difference are received, they can be combined to obtain a second optical signal, which is then sent to the polarization rotator 23 for polarization rotation to obtain a signal that is polarized with the first optical signal E. TE The second optical signal E with orthogonal polarization states TM .

[0117] In this embodiment, the first micro-ring modulation submodule 22 and the second micro-ring modulation submodule 22' have the same structure. The first micro-ring modulation submodule 22 includes: a first beam splitter 221, a first I-channel micro-ring modulation unit 222, a first Q-channel micro-ring modulation unit 223, a first phase shifter 224, and a first beam combiner 225. This allows the first and second light waves emitted from the multi-wavelength light source to be split into two again by the beam splitter, and the four light waves are modulated by the micro-rings to form two sets of I and Q signals (Ex-I, Ex-Q; Ey-I, Ey-Q). Coherent modulation of the signal light can be achieved through IQ modulation. Then, the IQ signals are synthesized into the first and second optical signals, respectively. After polarization adjustment, the second optical signal is coupled with the first optical signal to obtain a composite optical signal. This achieves orthogonal polarization states of the two sets of signals, resulting in a higher transmission rate and better anti-interference performance.

[0118] refer to Figure 3 , Figure 3 This is a structural block diagram of the third embodiment of the photonic integrated multi-wavelength coherent transmitter of the present invention, as shown below. Figure 3 As shown, in this embodiment, the first I-channel micro-ring modulation unit 222 and the first Q-channel micro-ring modulation unit 223 have the same structure.

[0119] The first I-path micro-ring modulation unit 222 comprises a first I-path beam splitter 2221a, a first I-path upper micro-ring modulation component 2222a, a first I-path lower micro-ring modulation component 2223a, a first I-path phase shifter 2224a, and a first I-path beam combiner 2225a. The first I-path beam splitter 2221a is connected with the first beam splitter 221, the first I-path upper micro-ring modulation component 2222a, and the first I-path lower micro-ring modulation component 2223a respectively. The first I-path lower micro-ring modulation component 2223a is connected with the first I-path phase shifter 2224a in series and then connected with the first I-path upper micro-ring modulation component 2222a in parallel. The first I-path upper micro-ring modulation component 2222a is further connected with the first I-path beam combiner 2225a, and the first I-path beam combiner 2225a is further connected with the first beam combiner 225.

[0120] In the first I-path micro-ring modulation unit 222, Figure 3 The first Q-path micro-ring modulation unit 223 comprises a first Q-path beam splitter 2221b, a first Q-path upper micro-ring modulation component 2222b, a first Q-path lower micro-ring modulation component 2223b, a first Q-path phase shifter 2224b, and a first Q-path beam combiner 2225b.

[0121] The second I-path micro-ring modulation unit 222' comprises a second I-path beam splitter 2221c, a second I-path upper micro-ring modulation component 2222c, a second I-path lower micro-ring modulation component 2223c, a second I-path phase shifter 2224c, and a second I-path beam combiner 2225c.

[0122] The second Q-path micro-ring modulation unit 223' comprises a second Q-path beam splitter 2221d, a second Q-path upper micro-ring modulation component 2222d, a second Q-path lower micro-ring modulation component 2223d, a second Q-path phase shifter 2224d, and a second Q-path beam combiner 2225d.

[0123] It can be understood that, since the first I-path micro-ring modulation unit 222, the first Q-path micro-ring modulation unit 223, the second I-path micro-ring modulation unit 222', and the second Q-path micro-ring modulation unit 223' have the same structure, the following description of the optical wave modulation process is taken as an example of the first I-path micro-ring modulation unit 222.

[0124] The first I-path beam splitter 2221a is configured to divide the I-path optical wave into a first I-path upper optical wave and a first I-path lower optical wave, and transmit the first I-path upper optical wave to the first I-path upper micro-ring modulation component 2222a and transmit the first I-path lower optical wave to the first I-path lower micro-ring modulation component 2223a.

[0125] It should be noted that, in order to facilitate the distinction, the modulated optical signal of the first I-path (Ix-path) optical wave can be represented as E-Ix, and the modulated optical signal of the first I-path The light signal modulated by the light wave can be expressed as

[0126]

[0127] The first I-uplink micro-ring modulation component 2222a is configured to modulate the first I-uplink light wave to obtain a first I-uplink light signal and send the first I-uplink light signal to the first I-beam combiner 2225a.

[0128] The first I-downlink micro-ring modulation component 2223a is configured to modulate the first I-downlink light wave to obtain a first I-downlink light signal and send the first I-downlink light signal to the first I-phase shifter 2224a.

[0129] It can be understood that the first modulation and the second modulation constitute differential modulation of the I-path light wave.

[0130] The first I-phase shifter 2224a is configured to adjust the phase of the first I-downlink light signal and send the adjusted first I-downlink light signal to the first I-beam combiner 2225a.

[0131] The first I-beam combiner 2225a is configured to perform signal light interference and signal synthesis of the first I-uplink light signal and the first I-downlink light signal to obtain an I-path light signal and send the I-path light signal to the first beam combiner 225.

[0132] In a specific implementation, in order to realize differential modulation of the I-path light wave, the first I-beam splitter 2221a splits the I-path light wave into uplink and downlink light waves, and performs micro-ring modulation in the corresponding micro-ring modulation component to obtain E-Ix and Next The first I-phase shifter 2224a is configured to adjust the phase of the first I-downlink light signal and send the adjusted first I-downlink light signal to the first I-beam combiner 2225a. The light signals of the two paths have a phase difference, and finally the first I-phase shifter 2224a performs two-path beam combining to realize interference and merging output of Ix and

[0133] Further, in order to realize differential modulation of the I-path light wave, reference can be made to Figure 4 The structure of the first I-path micro-ring modulation unit 222 is described as follows, Figure 4 FIG. 3 is a structure diagram of the first I-path micro-ring modulation unit in the third embodiment of the photonic integrated multi-wavelength coherent transmitter.

[0134] In Figure 4 ​In the first I upper-path micro-ring modulation component 2222a, there are: a first I upper-path micro-ring modulator array 201a and a first I upper-path driver array 202a; the first I lower-path micro-ring modulation component 2223a includes: a first I lower-path micro-ring modulator array 201b and a first I lower-path driver array 202b.

[0135] The first I upper micro-ring modulator array 201a and the first I lower micro-ring modulator array 201b have the same structure; each driver in the first I upper driver array 202a and each driver in the first I lower driver array 202b are complementary with corresponding upper and lower arms.

[0136] The first I-channel micro-ring modulator array 201a contains N resonant wavelengths (λ1~λ2). N The micro-ring modulator array, wherein each micro-ring (201a-1 to 201a-N) corresponds to N wavelengths of light, and the first I-channel driver array 202a contains N drivers (202a-1 to 202a-N).

[0137] Accordingly, the first I-channel micro-ring modulator array 201b contains N resonant wavelengths (λ1~λ2). N The array of micro-ring modulators, wherein each micro-ring (201b-1 to 201b-N) corresponds to N wavelengths of light, and the first I-channel driver array 202b contains N drivers (202b-1 to 202b-N).

[0138] The following description uses the structure of the first I upper-path micro-ring modulation component 2222a as an example to illustrate its specific functions.

[0139] The first I-channel micro-ring modulator array 201a is used to filter and modulate the first I-channel optical wave based on each of the micro-rings when the first I-channel optical wave is received, wherein the resonant wavelength of each of the micro-rings corresponds to each wavelength of the multi-wavelength light source.

[0140] It should be noted that when the first I upper-path optical wave is received, each micro-ring in the first I upper-path micro-ring modulator array 201a can perform wavelength selection on the optical wave contained in the first I upper-path optical wave to obtain an optical wave that is consistent with the resonant wavelength of each micro-ring, thereby realizing the modulation of a single wavelength by a single micro-ring.

[0141] The first I-channel driver array 202a is used to load the drive signal and send the drive signal to the first I-channel micro-ring modulator array 201a.

[0142] It should be noted that the first I uplink driver array 202a and the first I downlink driver array 202b can form a differential driver, that is, the signal loaded by the driver in the first I uplink driver array 202a is the complement of the signal loaded by the driver in the first I downlink driver array 202b, and then the uplink and downlink constitute a driver pair, realizing differential driving of the I path micro-ring modulator array (the first I uplink micro-ring modulator array 202a and the first I downlink micro-ring modulator array 202b).

[0143] The first I uplink micro-ring modulator array 201a is further configured to perform micro-ring modulation (first modulation) on the first I uplink light wave based on each micro-ring according to the driving signal, to obtain a first I uplink optical signal.

[0144] It should be noted that when the driver pair loads the driving signal on the corresponding micro-ring (λ1~λ N ) above, the signal is modulated on the corresponding first I uplink light wave, realizing the first modulation, obtaining the first I uplink optical signal E-Ix, and similarly, the signal opposite to the above-mentioned driving signal is loaded at the first I downlink micro-ring modulator array 201b, and micro-ring modulation (second modulation) is performed, obtaining the first I downlink optical signal E-Iy.

[0145] In addition, reference can be made to Figure 5 The differential modulation is realized by the micro-ring modulation of the two groups of I path and Q path, that is, the process of differentially modulating the four light waves (Ex-I, Ex-Q; Ey-I, Ey-Q) is described, Figure 5 The specific structure diagram of the photonic integrated multi-wavelength coherent transmitter.

[0146] In Figure 5 , the photonic integrated multi-wavelength coherent transmitter comprises a multi-wavelength light source 1, a total beam splitter 21, a first beam splitter 221, a second beam splitter 221', a first I path beam splitter 2221a, a first Q path beam splitter 2221b, a second I path beam splitter 2221c, and a second Q path beam splitter 2221d.

[0147] The first I uplink micro-ring modulator array 201a, the first I downlink micro-ring modulator array 201b, the first Q uplink micro-ring modulator array 201c, the first Q downlink micro-ring modulator array 201d, the second I uplink micro-ring modulator array 201e, the second I downlink micro-ring modulator array 201f, the second Q uplink micro-ring modulator array 201g, and the second Q downlink micro-ring modulator array 201h.

[0148] a first I up- and down- driver array 202a, 202b, a first Q up- and down- driver array 202c, 202d; a second I up- and down- driver array 202e, 202f, a second Q up- and down- driver array 202g, 202h.

[0149] a first I phase shifter 2224a, a first Q phase shifter 2224b, a second I phase shifter 2224c, a second Q phase shifter 2224d; a first I beam combiner 2225a, a first Q beam combiner 2225b, a second I beam combiner 2225c, a second Q beam combiner 2225d.

[0150] a first phase shifter 224, a second phase shifter 224'; a first beam combiner 225 and a second beam combiner 225'; a polarization rotator (PR) 23 and a polarization beam combiner (PBC) 24, an optical amplifier 3.

[0151] The light waves emitted by the multi-wavelength light source 1 are split into a first light wave (Ex light wave) and a second light wave (Ey light wave) by the total beam splitter 21, and then split into four light waves by the first beam splitter 221 and the second beam splitter 221', forming two groups of I and Q light waves (Ex-I, Ex-Q; Ey-I, Ey-Q). To achieve differential modulation of the I or Q light waves, the four light waves are split into two by the first I beam splitter 2221a, the first Q beam splitter 2221b, the second I beam splitter 2221c, and the second Q beam splitter 2221d, so that each I light wave is split into an upper and a lower light wave (Ix and Iy and ), and each Q light wave is split into an upper and a lower light wave (Qx and Qy and ); and in the modulation of each I / Q light wave, the upper and lower driver arrays load complementary driving signals to the corresponding upper and lower micro-ring modulator arrays to achieve differential modulation. The E-Ix, E-Qx, E-Iy, E-Qy, are obtained, wherein each lower light signal is phase-shifted and interferes with and combines with the corresponding upper light signal to obtain Ex-I, Ex-Q; Ey-I, Ey-Q.

[0152] To achieve IQ modulation, the Q light signal is phase-shifted and orthogonal to the corresponding I light signal to obtain Ex light signal and Ey light signal. Then the Ey light signal is rotated by the polarization rotator (PR) 23 to rotate the polarization state to be orthogonal to the first light signal E TEa second optical signal E of orthogonal polarization state TM Finally, the optical signals of different polarization states are combined by a polarization beam combiner (PBC) 24 to obtain a polarization composite optical signal, which is amplified by the optical amplifier 3 and output.

[0153] Further, in order to illustrate the modulation process of the I channel by the differential method, reference can be made to Figure 6 for illustration, Figure 6 is a structural schematic diagram of the I channel micro-ring modulator array in the third embodiment of the photonic integrated multi-wavelength coherent transmitter.

[0154] In Figure 6 , the I channel micro-ring modulator array can include a first I uplink micro-ring modulator array 202a and a first I downlink micro-ring modulator array 202b.

[0155] The heater array 2021a is configured to adjust the resonance wavelengths of the micro-rings of the preset number of wavelengths by power adjustment, so that the resonance wavelengths of the micro-rings correspond to the wavelengths of the multi-wavelength light source respectively.

[0156] It should be noted that the above harmonic adjustment process of the micro-rings can be performed before the optical wave modulation based on the micro-rings, so that the micro-rings filter the first I uplink optical wave.

[0157] The electrode array 2023a is configured to receive the driving signals loaded by the driver array and send the driving signals to the micro-ring structure.

[0158] The micro-ring structure 2022a is configured to modulate the first I uplink optical wave by the driving signals to obtain a first I uplink optical signal (E-Ix).

[0159] In Figure 6 , the first I uplink micro-ring modulation component 2222a further includes an incoming waveguide 203a and an outgoing waveguide 204a.

[0160] The micro-ring structure 2022a includes a micro-ring structure input end 20221a, a micro-ring straight waveguide 20222a, a micro-ring structure output end 20223a, and a preset number of micro-rings (2022a-1~2022a-N).

[0161] Each heater (2021a-1~2021a-N) in the heater array 2021a, each signal loading electrode pair {(2023a-11, 2023a-12)~(2023a-N1, 2023a-N2)} in the electrode array 2023a, and each micro ring (2022a-1~2022a-N) correspond to each other respectively.

[0162] It should be noted that each heater (2021a-1~2021a-N) has two electrodes {(2021a-11, 2021a-12)~(2021a-N1, 2021a-N2)}, and the resonant wavelength of the N micro rings is adjusted by adjusting the power on the heater, so as to ensure that the resonant wavelength of the micro ring is aligned with the N wavelengths of the light wave.

[0163] The micro ring structure input end 20221a is configured to receive the first I uplink light wave transmitted by the incoming waveguide 203a, transmit the first I uplink light wave to the micro ring straight waveguide 20222a, and send the driving signal to the preset number of micro rings (2022a-1~2022a-N) through each signal loading electrode pair {(2023a-11, 2023a-12)~(2023a-N1, 2023a-N2)}, so as to perform micro ring modulation on the first I uplink light wave based on each micro ring according to the driving signal, and obtain a first I uplink optical signal.

[0164] The micro ring straight waveguide 20222a is further configured to transmit the obtained first I uplink optical signal (E-Ix) to the outgoing waveguide 204a based on the micro ring structure output end 20223a when each micro ring completes modulation on the first I uplink light wave through the driving signal.

[0165] Similarly, the modulation processes of E-Qx, E-Iy, E-Qy, are not described here. E-Ix and the phase-adjusted are combined to obtain Ex-I; E-Qx and the phase-adjusted are combined to obtain Ex-Q; E-Iy and the phase-adjusted are combined to obtain Ey-I; and E-Qy and the phase-adjusted are combined to obtain Ey-Q.

[0166] In this embodiment, the resonant wavelength of the N micro-rings is adjusted by adjusting the power on the heater to ensure that the resonant wavelength of the micro-ring is aligned with the N wavelengths of the light wave. In a single path (I path or Q path), two groups of driver arrays are used to drive two independent micro-ring modulator arrays by using differential driving, and differential driving voltage signals are loaded, and the signals transmitted by the two lines are complementary to each other, so that the signals are modulated onto the corresponding N given wavelengths of the light wave, and differential modulation is realized.

[0167] Further, reference can be made to Figure 7 The application of the photonic integrated multi-wavelength coherent transmitter A in an optical transceiver system is described, Figure 7 The structure block diagram of the optical transceiver system comprising the photonic integrated multi-wavelength coherent transmitter is shown.

[0168] In Figure 7 , the photonic integrated multi-wavelength coherent transmitter A is connected with a multi-wavelength coherent receiver B;

[0169] The multi-wavelength coherent receiver B comprises a polarization beam splitting and rotating module B1, a local oscillator beam splitting module B2, and a coherent light demodulation module B3, wherein the coherent light demodulation module B3 comprises a first optical signal demodulation sub-module B31 and a second optical signal demodulation sub-module B32;

[0170] The polarization beam splitting and rotating module B1 is connected with the first optical signal demodulation sub-module B31 and the second optical signal demodulation sub-module B32, respectively, and the local oscillator beam splitting module B2 is connected with the first optical signal demodulation sub-module B31 and the second optical signal demodulation sub-module B32, respectively.

[0171] The polarization beam splitting and rotating module B1 is configured to perform orthogonal beam splitting on the composite optical signal when the composite optical signal is received, and send the orthogonally beam-splitting composite optical signal to the first optical signal demodulation sub-module B31 and the second optical signal demodulation sub-module B32, respectively.

[0172] The local oscillator beam splitting module B2 is configured to obtain local oscillator light corresponding to the light wave, split the local oscillator light, and send the split local oscillator light to the first optical signal demodulation sub-module B31 and the second optical signal demodulation sub-module B32, respectively.

[0173] The first optical signal demodulation sub-module B31 and the second optical signal demodulation sub-module B32 are configured to obtain an optical current signal comprising phase information according to the orthogonally beam-splitting composite optical signal and the split local oscillator light.

[0174] Further, reference can be made to Figure 8 The specific structure of the optical transceiver system is described, Figure 8This is a schematic diagram of the specific structure of an optical transceiver system including the photonic integrated multi-wavelength coherent transmitter of the present invention.

[0175] exist Figure 8 In this system, the photonic integrated multi-wavelength coherent transmitter A and the multi-wavelength coherent receiver B are connected via an optical interconnect fiber link 00.

[0176] It should be noted that the polarization beam splitting and rotating module B1 can be a polarization beam splitter and a rotator (PRS). The PRS is used to split the beam after receiving a composite signal light containing two orthogonal polarization modes, and rotate one of the modes by 90 degrees, outputting the orthogonally split composite light as signal light S1 and signal light S2. Specifically, the first optical signal with a first polarization state TE maintains its polarization mode and is output as signal light S1, while the second optical signal with a second polarization state TM is rotated to become the first polarization state TE and is output as signal light S2.

[0177] It should be noted that the local oscillator beam splitter module B2 may include a local oscillator receiving device B201 and a local oscillator beam splitter B202.

[0178] exist Figure 8 In this context, the local oscillator light receiving device B201 may contain a local oscillator light source Lo that is exactly the same as the multi-wavelength light source 1 in the photonic integrated multi-wavelength coherent transmitter A. After receiving the local oscillator light wave, the local oscillator light receiving device B201 can split it into two identical local oscillator light L1 and local oscillator light L2 through the local oscillator light beam splitter B202.

[0179] The first optical signal demodulation submodule B31 is the same as the second optical signal demodulation submodule B32, and may include one of two sets of optical mixers B311 and B321 for demodulating two polarized signals, a demultiplexer group (B312-1 to B312-4 or B322-1 to B322-4), and a detector group (B313-1 to B313-4 or B323-1 to B323-4).

[0180] Signal light S1 and local oscillator light L1 are input to two input ports B311-a and B311-b of optical mixer B311, respectively. The relative phase differences of the four output ports (B311-1 to B311-4) of optical mixer B311 are 0°, 180°, 90°, and 270°, respectively. Therefore, the photocurrents obtained from ports B311-1 and B311-2 by detectors B313-1 and B313-2 recover E-Ix in the photonic integrated multiwavelength coherent transmitter A. The phase information, similarly, the photocurrents obtained from ports B311-3 and B311-4 via detectors B313-3 and B313-4, recover the E-Qx in the photonic integrated multi-wavelength coherent transmitter A. the phase information of E-Iy,

[0181] Similarly, the signal light S2 and the local light L2 are input to the two input ports B321-a and B321-b of the other optical mixer B321, and the relative phase difference of the four output ports (B321-1~B321-4) of the optical mixer B321 is 0°, 180°, 90°, and 270°, respectively. Therefore, the optical current obtained by the detectors B323-1 and B323-2 through the ports B321-1 and B321-2 recovers the phase information of E-Iy, of the photonic integrated multi-wavelength coherent transmitter A, and the optical current obtained by the detectors B323-3 and B323-4 through the ports B321-3 and B321-4 recovers the phase information of E-Qx, of the photonic integrated multi-wavelength coherent transmitter A.

[0182] Among them, the demultiplexers B312-1~B312-4 and B322-1~B322-4 can separate the signal light of N wavelengths.

[0183] In addition, considering that the local light along the way is used as the input local light in the multi-wavelength coherent receiver B, it is necessary to ensure the consistency of the local light and the initial light wave in the photonic integrated multi-wavelength coherent transmitter A, ensure the correctness of the demodulation signal, reduce the bit error rate, and improve the anti-interference performance of the equipment. Therefore, the light wave emitted by the multi-wavelength light source 1 in the photonic integrated multi-wavelength coherent transmitter A can be directly used as the local light Lo.

[0184] Here, the Figure 9 can be explained, Figure 9 is another specific structure diagram of an optical transceiver system comprising the photonic integrated multi-wavelength coherent transmitter of the application.

[0185] In Figure 9 , the local light receiving device B201 can receive the light wave directly provided by the multi-wavelength light source 101 in the photonic integrated multi-wavelength coherent transmitter A as the local light source Lo.

[0186] It should be noted that in Figure 9 , the multi-wavelength light source 1 in the above-mentioned photonic integrated multi-wavelength coherent transmitter A and the total beam splitter 21 are further provided with a local-modulation beam splitter 1' for splitting the local light and the to-be-modulated light wave. The light wave transmitted by the multi-wavelength light source 1 is first split into a to-be-modulated light wave and a local light by the local-modulation beam splitter 1', and then input to the above-mentioned total beam splitter 21 and the local light receiving device B201, respectively.

[0187] It can be understood that the process of modulating the to-be-modulated light wave by the photonic integrated multi-wavelength coherent transmitter A and the process of demodulating the modulated light wave in the multi-wavelength coherent receiver B can refer to the above, and the present embodiment will not be described here.

[0188] It should be understood that the application of the photonic integrated multi-wavelength coherent transmitter to the optical transceiver system can obtain the phase information of E-Ix, E-Qx, E-Iy, E-Qx, in the optical current recovery transmitter at the port detector of the multi-wavelength coherent receiver in the optical transceiver system, so as to realize the modulation-demodulation process of the optical wave. Further, when the system contains N-wavelength signal light, the size of the transmitter can be reduced by using the micro-ring modulation, which is conducive to improving the integration of the system.

[0189] In addition, based on the above-mentioned photonic integrated multi-wavelength coherent transmitter A, a single-polarization coherent transceiver system containing a multi-wavelength coherent transmitter A' can be proposed. Figure 10 , Figure 10 is a structure block diagram of the single-polarization optical transceiver system based on the photonic integrated multi-wavelength coherent transmitter of the application.

[0190] In Figure 10 , the multi-wavelength coherent transmitter A' comprises:

[0191] a multi-wavelength light source 301, a first beam splitter 302, an I-path beam splitter 303a, a Q-path beam splitter 303b, an I-up-path driver group 310a, an I-up-path micro-ring modulator array 304a, an I-down-path micro-ring modulator array 314a, an I-down-path driver group 319a, an I-path phase shifter 305a, an I-path beam combiner 306a, a Q-up-path driver group 310b, a Q-up-path micro-ring modulator array 304b, a Q-down-path micro-ring modulator array 314b, a Q-down-path driver group 319b, a Q-path phase shifter 305b, a Q-path beam combiner 306b, a first phase shifter 307, a first beam combiner 308, and an optical amplifier 309.

[0192] The multi-wavelength coherent transmitter A' is connected to a multi-wavelength coherent receiver B' through an optical interconnection optical fiber link 320. The coupler 322 in the multi-wavelength coherent receiver B' receives the signal light emitted by the multi-wavelength coherent transmitter A'.

[0193] The multi-wavelength coherent receiver B' further comprises a local light (Lo) receiving device 321, an optical mixer 323, a demultiplexer (Demux) group (324-1~324-4), and a photodetector (PD) group (325-1~325-4). The optical mixer 323 comprises two input ports 326-1 and 326-2, and four output ports (327-1~327-4).

[0194] In the multi-wavelength coherent transmitter A', the multi-wavelength light source 301 emits light of N wavelengths, which is divided into I and Q two paths through the first beam splitter 302. Then, the light waves of the I and Q two paths are divided into upper and lower two paths, which are marked as I path, path, Q path and path respectively. The four light waves are input into the corresponding micro-ring modulator arrays 304a, 304b, 314a and 314b respectively, and the differential modulation of the light waves is realized based on the corresponding micro-ring modulators through the differential modulation signals loaded in the driver groups (310a, 310b, 319a and 319b). The differential modulation signals loaded in 310a and 310b and 319a and 319b are complementary signals, which constitute differential driving.

[0195] path and The I path phase shifter 305a and the Q path phase shifter 305b are used to adjust the phase of the signals, and the interference and beam combination of the optical signals are realized through the I path beam combiner 306a and the Q path beam combiner 306b. Then, the light output from the Q path beam combiner 306b is changed by π / 2 through the first phase shifter 307, so as to realize the orthogonality of the I path and Q path signal light. Finally, the signal light is combined and amplified through the first beam combiner 308 and the optical amplifier 309.

[0196] The amplified signal light is coupled into the optical interconnection fiber link 320, and after transmission, it reaches the coherent receiver B' end. The signal light is fed into the coherent receiver through the optical coupler 322. The local light (Lo) receiving device 321 is the same light source as the multi-wavelength light source 301 in the multi-wavelength coherent transmitter A'. The signal light S and the local light L are input into the two input ports 326-1 and 326-2 of the optical mixer 323 respectively, and the relative phase difference of the four output ports 327-1 to 327-4 of the optical mixer is 0°, 180°, 90° and 270° respectively. Therefore, the photocurrents obtained by the photodetectors (PDs) 325-1 and 325-2 through the ports 327-1 and 327-2 recover the phase information of the I path signal at the transmitting end, and the photocurrents obtained by the photodetectors (PDs) 325-3 and 325-4 through the ports 327-3 and 327-4 recover the phase information of the Q path signal at the transmitting end. The demultiplexer 324-1 to 324-4 can separate the signal light of N wavelengths.

[0197] In addition, in order to achieve the above object, the application further provides a photonic integrated multi-wavelength coherent emission method based on the photonic integrated multi-wavelength coherent transmitter A. Figure 11 , Figure 11 The flowchart of the first embodiment of the photonic integrated multi-wavelength coherent emission method of the application is shown in the figure.

[0198] Based on the above embodiment, in the embodiment, the photonic integrated multi-wavelength coherent emission method comprises the following steps:

[0199] Step S10: Obtain optical waves of a preset wavelength number, and the optical waves are first optical waves and second optical waves.

[0200] It should be noted that the embodiments of the application can be applied in the field of optical communication, and can be specifically applied in the scene of modulating multi-wavelength optical waves such as polarization multiplexing, wavelength division multiplexing, quadrature phase shift keying (QPSK), quadrature amplitude modulation (QAM), etc. The execution subject of the embodiment of the application can be the photonic integrated multi-wavelength coherent transmitter A as described above.

[0201] Step S20: Micro-ring modulation is performed on the first optical wave and the second optical wave respectively according to the preset wavelength number, to obtain first optical signals and second optical signals.

[0202] Step S30: Polarization rotation is performed on the second optical signal.

[0203] Step S40: The first optical signal and the second optical signal after polarization rotation are coupled to obtain a polarization composite optical signal, and the polarization composite optical signal is amplified and emitted.

[0204] Further, in order to specifically describe the process of micro-ring modulation on the first / second optical wave, reference can be made to Figure 12 , Figure 12 The flowchart of the step of micro-ring modulation on the first / second optical wave in the photonic integrated multi-wavelength coherent emission method of the application is shown in the figure. Therefore, step S20 further comprises:

[0205] Step S201: When the first / second optical wave is obtained, the first / second optical wave is divided into I-path optical waves and Q-path optical waves.

[0206] Step S202: The I-path optical waves and the Q-path optical waves are differentially modulated based on the micro-rings of the preset wavelength number respectively, to obtain I-path optical signals and Q-path optical signals.

[0207] Step S203: Phase adjustment is performed on the Q-path optical signal.

[0208] Step S204: combining the I light signal and the phase-adjusted Q light signal to obtain a first / two light signals.

[0209] Further, to specifically describe the process of micro-ring modulation of the I / Q light waves, reference can be made to Figure 13 , Figure 13 A flowchart of the step of micro-ring modulation of the I / Q light waves in the photonics integrated multi-wavelength coherent emission method of the present application. Therefore, step S202 comprises:

[0210] Step S2021: when the I / Q light waves are obtained, the I / Q light waves are divided into uplink light waves and downlink light waves.

[0211] Step S2022: the uplink light waves and the downlink light waves are modulated based on the micro-ring of the preset number of wavelengths to obtain uplink light signals and downlink light signals.

[0212] Step S2023: the downlink light signals are phase-adjusted.

[0213] Step S2024: the uplink light signals and the phase-adjusted downlink light signals are combined to obtain I / Q light signals.

[0214] In addition, reference can also be made to Figure 14 A full flow of the photonics integrated multi-wavelength coherent emission method of the present application is described, Figure 14 a full flowchart of the photonics integrated multi-wavelength coherent emission method of the present application.

[0215] A1: a multi-wavelength light source (laser) emits N wavelengths of light waves, wherein each wavelength spacing is equal and greater than or equal to 2;

[0216] A2: the light waves pass through a total beam splitter to be divided into two, obtaining a first light wave (Ex light wave) and a second light wave (Ey light wave), which then pass through a first beam splitter and a second beam splitter again to be divided into two, respectively forming two groups of I, Q light waves (Ex-I, Ex-Q; Ey-I, Ey-Q);

[0217] A3: the four light waves pass through a beam splitter again to be divided into two, obtaining Ix and Iy and Qx and Qy and

[0218] A4: the eight light waves are input into the corresponding micro-ring modulator array to be modulated, obtaining E-Ix, E-Qx, E-Iy, E-Qy,

[0219] A5: and After phase adjustment by the phase shifter, the I and Q signals are combined with the corresponding uplink optical signals to obtain Ex-I, Ex-Q; Ey-I, Ey-Q;

[0220] A6: Ex-Q and Ey-Q are combined with the corresponding I signals after phase adjustment to obtain Ex and Ey, wherein Ey is converted by a polarization rotator to change the polarization state by 90 degrees;

[0221] A7: The two groups of optical signals with different polarization states are combined by a polarization beam combiner and then amplified;

[0222] A8: The signals are emitted by the transmitter and coupled into the optical transmission fiber link to the receiver end.

[0223] In this embodiment, the light waves emitted by the multi-wavelength light source are divided into two paths, then divided again by a beam splitter to form two groups of I and Q signals (Ex-I, Ex-Q, Ey-I, Ey-Q), which can realize coherent modulation of the signal light through IQ modulation, and the four light waves (each I / Q light wave) are divided again by a beam splitter to obtain eight light waves (Ix and Iy and Qx and Qy and Through the complementary driver group of the upper and lower arms, differential modulation is realized to obtain E-Ix, E-Qx, E-Iy, E-Qy, Furthermore, each group of upper and lower signals is synthesized into I / Q light signals, each group of IQ signals is synthesized into a first optical signal Ex and a second optical signal Ey, and the second optical signal is coupled with the first optical signal after polarization rotation to obtain a composite optical signal, realizing the polarization state orthogonality of the two groups of signals, which is conducive to improving the data transmission rate while ensuring the anti-interference of the optical signal.

[0224] The other embodiments or specific implementation manners of the photon integrated multi-wavelength coherent emission method can refer to the above-mentioned embodiments of the photon integrated multi-wavelength coherent transmitter, which will not be repeated here.

[0225] It should be noted that, in the present document, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, circuit, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, circuit, article, or apparatus. Without further limitation, an element preceded by "comprises a" does not, without more limitations, foreclose the existence of additional identical elements in the process, circuit, article, or apparatus that comprises the element.

[0226] The above-mentioned embodiment serial numbers of the present application are only for description, and do not represent the advantages and disadvantages of the embodiments.

[0227] The above is only the preferred embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent process transformation using the content of the present application specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A photonic integrated multi-wavelength coherent transmitter, characterized in that, The photon integrated multi-wavelength coherent transmitter comprises a multi-wavelength light source, a transmitter modulation module and an optical amplifier; The transmitter modulation module comprises a total beam splitter, a first micro-ring modulation submodule, a second micro-ring modulation submodule, a polarization rotator and a polarization light beam combiner; The total beam splitter is connected with the multi-wavelength light source, the first micro-ring modulation submodule and the second micro-ring modulation submodule respectively, the second micro-ring modulation submodule is connected with the polarization rotator in series and then connected with the first micro-ring modulation submodule in parallel, the first micro-ring modulation submodule is further connected with the polarization light beam combiner, and the polarization light beam combiner is further connected with the optical amplifier; The multi-wavelength light source is configured to generate light waves of a preset wavelength number and send the light waves to the total beam splitter; The total beam splitter is configured to divide the light waves into first light waves and second light waves, send the first light waves to the first micro-ring modulation submodule and send the second light waves to the second micro-ring modulation submodule; The first micro-ring modulation submodule is configured to differentially modulate the first light waves based on the preset wavelength number, obtain first optical signals and send the first optical signals to the polarization light beam combiner; The second micro-ring modulation submodule is configured to differentially modulate the second light waves based on the preset wavelength number, obtain second optical signals and send the second optical signals to the polarization rotator; The polarization rotator is configured to perform polarization rotation on the second optical signals and send the second optical signals after polarization rotation to the polarization light beam combiner; The polarization light beam combiner is configured to couple the first optical signals and the second optical signals after polarization rotation, obtain composite optical signals and send the composite optical signals to the optical amplifier; The optical amplifier is configured to amplify and emit the composite optical signals; The first micro-ring modulation submodule and the second micro-ring modulation submodule are of the same structure; the first micro-ring modulation submodule comprises a first beam splitter, a first I-path micro-ring modulation unit, a first Q-path micro-ring modulation unit, a first phase shifter and a first beam combiner; The first beam splitter is connected with the total beam splitter, the first I-path micro-ring modulation unit and the first Q-path micro-ring modulation unit respectively, the first Q-path micro-ring modulation unit and the first phase shifter are connected in series and then connected with the first I-path micro-ring modulation unit in parallel, the first I-path micro-ring modulation unit is further connected with the first beam combiner, and the first beam combiner is further connected with the polarization light beam combiner; The first I-path micro-ring modulation unit and the first Q-path micro-ring modulation unit are of the same structure, and the first I-path micro-ring modulation unit comprises a first I-path beam splitter, a first I-path upper micro-ring modulation assembly, a first I-path lower micro-ring modulation assembly, a first I-path phase shifter and a first I-path beam combiner; The first I-branch beam splitter is connected with the first beam splitter, the first I-uplink micro-ring modulation assembly, and the first I-downlink micro-ring modulation assembly respectively, the first I-downlink micro-ring modulation assembly is connected with the first I-uplink micro-ring modulation assembly in parallel after being connected with the first I-branch phase shifter in series, the first I-uplink micro-ring modulation assembly is further connected with the first I-branch beam combiner, and the first I-branch beam combiner is further connected with the first beam combiner; The first I-uplink micro-ring modulation assembly comprises a plurality of micro-rings corresponding to the number of wavelengths of the multi-wavelength light source, and the resonant wavelengths of the micro-rings correspond to the wavelengths of the multi-wavelength light source respectively; The first I-uplink micro-ring modulation assembly comprises a first I-uplink micro-ring modulator array and a first I-uplink driver array, and the first I-downlink micro-ring modulation assembly comprises a first I-downlink micro-ring modulator array and a first I-downlink driver array which constitute differential modulation; The first I-uplink micro-ring modulator array and the first I-downlink micro-ring modulator array are of the same structure and each comprise a heater array, a micro-ring structure, and an electrode array; The driving signals generated by the drivers in the first I-uplink driver array and the driving signals generated by the drivers in the first I-downlink driver array are complementary to each other in upper and lower arms; The micro-ring structure comprises a micro-ring structure input end, a micro-ring straight waveguide, a micro-ring structure output end, and a plurality of micro-rings of a preset wavelength number. The photonic integrated multi-wavelength coherent transmitter is further connected with a multi-wavelength coherent receiver, the multi-wavelength coherent receiver comprises a polarization light beam splitting and rotating module, a local oscillator light beam splitting module, and a coherent light demodulation module, the coherent light demodulation module comprises a first optical signal modulation sub-module and a second optical signal demodulation sub-module which are of the same structure, the first optical signal modulation sub-module comprises an optical mixer, a demultiplexer group, and a detector group, and the optical mixer has two input ports and four output ports.

2. The photonic integrated multi-wavelength coherent transmitter of claim 1, wherein, The first beam splitter is used for dividing the first light wave into I-branch light wave and Q-branch light wave, transmitting the I-branch light wave to the first I-branch micro-ring modulation unit, and transmitting the Q-branch light wave to the first Q-branch micro-ring modulation unit; The first I-branch micro-ring modulation unit is used for performing differential modulation on the I-branch light wave based on the preset wavelength number of micro-rings, obtaining an I-branch optical signal, and transmitting the I-branch optical signal to the first beam combiner; The first Q-branch micro-ring modulation sub-module is used for performing differential modulation on the Q-branch light wave based on the preset wavelength number of micro-rings, obtaining a Q-branch optical signal, and transmitting the Q-branch optical signal to the first phase shifter; The first phase shifter is used for adjusting the phase of the Q-branch optical signal and transmitting the adjusted Q-branch optical signal to the first beam combiner; The first beam combiner is used for performing signal synthesis on the I-branch optical signal and the Q-branch optical signal, obtaining a first optical signal, and transmitting the first optical signal to the polarization light beam combiner.

3. The photonic integrated multi-wavelength coherent transmitter of claim 2, wherein, The first I-branch beam splitter is configured to split the I-branch light wave into a first I-branch uplink light wave and a first I-branch downlink light wave, and transmit the first I-branch uplink light wave to the first I-branch uplink micro-ring modulation assembly and transmit the first I-branch downlink light wave to the first I-branch downlink micro-ring modulation assembly. The first I-branch uplink micro-ring modulation assembly is configured to perform first modulation on the first I-branch uplink light wave to obtain a first I-branch uplink optical signal, and transmit the first I-branch uplink optical signal to the first I-branch combiner. The first I-branch downlink micro-ring modulation assembly is configured to perform second modulation on the first I-branch downlink light wave to obtain a first I-branch downlink optical signal, and transmit the first I-branch downlink optical signal to the first I-branch phase shifter. The first modulation and the second modulation constitute differential modulation on the I-branch light wave. The first I-branch phase shifter is configured to perform phase adjustment on the first I-branch downlink optical signal, and transmit the adjusted first I-branch downlink optical signal to the first I-branch combiner. The first I-branch combiner is configured to perform signal light interference and synthesis on the first I-branch uplink optical signal and the first I-branch downlink optical signal to obtain an I-branch optical signal, and transmit the I-branch optical signal to the first combiner.

4. The photonic integrated multi-wavelength coherent transmitter of claim 3, wherein, The first I-branch uplink micro-ring modulator array is configured to, when receiving the first I-branch uplink light wave, filter and modulate the first I-branch uplink light wave based on each micro-ring, wherein the resonance wavelength of each micro-ring corresponds to each wavelength of the multi-wavelength light source respectively. The first I-branch uplink driver array is configured to load a driving signal and transmit the driving signal to the first I-branch uplink micro-ring modulator array. The first I-branch uplink micro-ring modulator array is further configured to, based on each micro-ring, perform micro-ring modulation on the first I-branch uplink light wave according to the driving signal to obtain a first I-branch uplink optical signal.

5. The photonic integrated multi-wavelength coherent transmitter of claim 4, wherein, The heater array is configured to adjust the resonance wavelength of each micro-ring of the preset number of wavelengths by power adjustment, so that the resonance wavelength of each micro-ring corresponds to each wavelength of the multi-wavelength light source respectively. The electrode array is configured to receive the driving signal loaded by the driver array and transmit the driving signal to the micro-ring structure. The micro-ring structure is configured to perform micro-ring modulation on the first I-branch uplink light wave by the driving signal to obtain a first I-branch uplink optical signal.

6. The photonic integrated multi-wavelength coherent transmitter of claim 5, wherein, The first I-branch uplink micro-ring modulation assembly further comprises an incoming waveguide and an outgoing waveguide. Each heater in the heater array and each signal loading electrode in the electrode array correspond to each micro-ring respectively. The micro-ring structure input end is configured to receive the first I-branch uplink light wave transmitted by the incoming waveguide, transmit the first I-branch uplink light wave to the micro-ring straight waveguide, and transmit the driving signal to the preset number of micro-rings through each signal loading electrode pair, so as to, based on each micro-ring, perform micro-ring modulation on the first I-branch uplink light wave according to the driving signal to obtain a first I-branch uplink optical signal. The micro-ring straight waveguide is also used to transmit the obtained first I upper-path optical signal to the output waveguide based on the output end of the micro-ring structure when each of the micro-rings modulates the first I upper-path optical wave through the driving signal.

7. A photonic integrated multi-wavelength coherent transmitter method based on the photonic integrated multi-wavelength coherent transmitter of any of claims 1-6, characterized in that, The method includes: Acquire light waves of a preset number of wavelengths, and classify the light waves as a first light wave and a second light wave; Micro-ring modulation is performed on the first light wave and the second light wave according to the preset number of wavelengths to obtain the first optical signal and the second optical signal; The polarization of the second optical signal is rotated. The first optical signal and the second optical signal after polarization rotation are coupled to obtain a polarized composite optical signal, which is then amplified and emitted.

8. The photonic integrated multi-wavelength coherent emission method of claim 7, wherein, The step of performing micro-ring modulation on the first light wave and the second light wave according to the preset number of wavelengths to obtain the first optical signal and the second optical signal includes: When the first / second light wave is obtained, the first / second light wave is divided into I-path light wave and Q-path light wave; Differential modulation is performed on the I-channel optical wave and the Q-channel optical wave based on a preset number of micro-rings to obtain the I-channel optical signal and the Q-channel optical signal; Phase adjustment is performed on the Q-channel optical signal; The I-channel optical signal and the phase-adjusted Q-channel optical signal are combined to obtain the first / second optical signal.

9. The photonic integrated multi-wavelength coherent emission method of claim 8, wherein, The step of differentially modulating the I-channel and Q-channel optical waves based on a preset number of micro-rings to obtain the I-channel optical signal and Q-channel optical signal includes: When obtaining the I / Q optical waves, the I / Q optical waves are divided into upper optical waves and lower optical waves; The upper and lower optical waves are modulated based on a preset number of micro-rings to obtain the upper and lower optical signals; Phase adjustment is performed on the downstream optical signal; The upper optical signal and the lower optical signal after phase adjustment are combined to obtain the I / Q optical signal.

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