Multi-source integrated ultra-high-speed optical communication system using side-emitting coherent array lasers

Abstract

This invention provides a multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser, relating to the field of optical communication technology. In the transmitting end laser source array, some laser sources output optical signals carrying data information, while others generate local reference signals. The data-carrying optical signals are phase- or amplitude-modulated by a high-speed modulator and then input to a polarization multiplexing module for polarization control of some or all of the optical signals. A merging module combines all optical signals and the local reference signal and outputs them to an optical fiber link. At the receiving end, a wavelength division module receives the optical signals output from the optical fiber link, separating the local reference signal and the data signal. A coherent detection module performs coherent detection on the data signal based on the local reference signal to obtain the data information. This invention achieves Pb / s level or even unlimited data transmission capabilities through multi-channel laser sources, high-speed modulators, and adaptive local reference optical paths, possessing high bandwidth, low bit error rate, and high integration.

Description

Technical Field

[0001] This invention relates to the field of optical communication technology, and to a multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser. Background Technology

[0002] With the explosive growth of services such as artificial intelligence, cloud computing, edge computing, and high-definition video, global data traffic is increasing exponentially. Traditional coherent optical communication systems typically use discrete devices to implement light source, modulation, and detection functions, resulting in low integration. In this case, the output power, linewidth, and stability of discrete light sources are insufficient to meet the requirements of high-speed transmission. Discrete modulation and detection devices lack efficient coordination and cannot process high-speed signals in a timely manner. At speeds above Tb / s, the phase, amplitude, and polarization state of signals change extremely rapidly, making it difficult for discrete devices to accurately track and process these changes. Low system integration also leads to poor compatibility between DSPs and other discrete devices, preventing the full utilization of DSPs in areas such as dispersion compensation, noise suppression, and nonlinearity elimination, resulting in degraded signal quality and increased bit error rate. Therefore, traditional coherent optical communication systems are unable to meet the demands of future Tb / s and even Pb / s speeds.

[0003] In recent years, the development of novel materials and processes such as thin-film lithium niobate (LiNbO3) and silicon photonics platforms has made it possible to realize high-performance, low-cost integrated coherent optical communication systems. However, the following problems still exist in existing technologies:

[0004] (1) The modulator bandwidth is limited and it is difficult to support a single-channel rate of Tb / s;

[0005] (2) Low integration of multi-channel systems leads to a sharp increase in power consumption, cost and complexity;

[0006] (3) The local reference signal (LO) depends on an external light source, which limits the flexibility and scalability of the system;

[0007] (4) Lack of a unified architecture to support the collaborative work of multiple multiplexing methods such as polarization multiplexing, wavelength division multiplexing, and space division multiplexing.

[0008] Therefore, there is an urgent need to build a highly integrated, multi-dimensional multiplexed, and flexibly adaptable coherent optical communication system to meet future communication demands at the 1000Tbps level and even the Pb / s level. Summary of the Invention

[0009] To address the aforementioned issues, this invention provides a multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser. By introducing a high-speed interferometric modulator array, a multi-dimensional multiplexing mechanism, an adaptive local reference optical path, and a scalable receiver architecture, it achieves unlimited data transmission capability while maintaining low bit error rate, low cost, and high reliability.

[0010] To achieve the above objectives, the present invention provides a multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser, comprising a transmitter and a receiver;

[0011] The transmitter includes a laser source array connected in sequence. The optical signal output by at least one laser source in the laser source array is used to carry data information, and the optical signal output by the remaining at least one laser source is used to generate a local reference signal. All optical signals carrying data information are respectively input to a high-speed modulator. The high-speed modulator modulates the optical signals by phase or amplitude and outputs them to a polarization multiplexing module. The polarization multiplexing module controls the polarization of some or all of the optical signals and outputs them to a merging module. The merging module merges all the input optical signals and the local reference signal into one optical signal and outputs it to the optical fiber link.

[0012] The receiving end includes a wavelength division module, a coherent detection module, and a digital signal processing module connected in sequence. The wavelength division module receives the optical signal transmitted via the optical fiber link and separates the local reference optical signal and the data optical signal. The coherent detection module performs coherent detection on the data optical signal based on the local reference optical signal to obtain data information.

[0013] As a further improvement of the present invention, the laser source array adopts an integrated coherent array laser or a standalone laser array.

[0014] As a further improvement of the present invention, high-precision synchronization of each laser source in the laser source array is controlled by a phase-locked loop or an optical phase-locked circuit.

[0015] As a further improvement of the present invention, the high-speed modulator is an interference-type structure based on thin-film lithium niobate, silicon photonics, indium phosphide or polymer materials, including a Mach-Zehnder interferometer, a ring resonant cavity and a directional coupler, with a bandwidth of not less than 40 GHz.

[0016] As a further improvement of the present invention, the polarization multiplexing module includes a polarization controller, a waveplate and a polarization beam splitter arranged in sequence to dynamically adjust the polarization state of the optical signal.

[0017] As a further improvement of the present invention, the laser source array integrates a thermoelectric modulation unit, which controls the temperature of the laser in the laser source array to achieve rapid wavelength stabilization.

[0018] As a further improvement of the present invention, the merging module employs a wavelength division multiplexer or a spatial multiplexer to merge all data optical signals and local reference signals according to wavelength or spatial dimension.

[0019] As a further improvement of the present invention, the merging module integrates an optical amplifier, a filter, and an isolator.

[0020] As a further improvement of the present invention, the coherent detection includes self-zero difference detection, heterodyne detection, or same-frequency zero difference detection.

[0021] As a further improvement of the present invention, the wavelength division module separates the optical signal through a wavelength division multiplexer or an optoelectronic hybrid filter.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] This invention relates to a multi-source integrated ultra-high-speed optical communication system using a side-emission coherent array laser. Through a multi-channel laser source, a high-speed modulator array, and an adaptive local reference optical path design, it achieves data transmission capabilities at the Pb / s level and even with no upper limit, while possessing core advantages such as high bandwidth, low bit error rate, and high integration. This system is suitable for ultra-high-speed optical communication scenarios such as data center interconnection, 6G fronthaul / midhaul / backhaul, metropolitan area networks, and backbone networks, and has broad market prospects and application value.

[0024] The communication system of this invention has ultra-high bandwidth, with a single modulator bandwidth of ≥ 40 GHz and up to 100 GHz, supporting Tb / s level single-channel rates; combined with multi-dimensional multiplexing (WDM, SDM, PolMux) combinations, it achieves Pb / s level total rates; the system design supports an infinitely expandable architecture, and theoretically there is no bandwidth limit.

[0025] The communication system of this invention has ultra-large capacity, supports multiple modulation formats (QPSK, QAM, DP-QAM, etc.) and multidimensional multiplexing, significantly improving spectrum efficiency; polarization multiplexing doubles the channel capacity, and WDM provides tens to hundreds of channels for parallel transmission; it supports a flexible expansion mechanism, which can increase the number of channels at any time according to service needs.

[0026] The communication system of this invention features a low bit error rate, with the local reference signal and data signal sharing the same source, reducing the impact of phase noise; coherent detection technology provides high sensitivity and anti-interference capability, significantly reducing the bit error rate; DSP and AI technologies assist demodulation, further improving signal recovery accuracy.

[0027] The communication system of this invention has a high degree of integration, and all modules can be implemented using integrated chips; it is particularly suitable for silicon photonics platforms or thin-film lithium niobate platforms, and supports large-scale production and deployment.

[0028] The communication system of this invention reduces dependence on external light sources, thereby reducing system complexity and maintenance costs; its highly integrated design reduces the number of components, thus lowering manufacturing costs; and it supports modular deployment, facilitating later maintenance and upgrades. Attached Figure Description

[0029] Figure 1This is a schematic diagram of the complete structure of a multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser, as disclosed in one embodiment of the present invention.

[0030] Figure 2 This is a detailed structural diagram of the transmitter end of a multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser, as disclosed in one embodiment of the present invention.

[0031] Figure 3 This is a detailed structural diagram of the receiver end of a multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser, as disclosed in one embodiment of the present invention. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] The present invention will now be described in further detail with reference to the accompanying drawings:

[0034] like Figure 1 As shown, the present invention provides a multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser, comprising a transmitter and a receiver.

[0035] The transmitter includes a laser source array connected in sequence. The optical signal output by at least one laser source in the laser source array is used to carry data information, and the optical signal output by the remaining at least one laser source is used to generate a local reference signal. All optical signals carrying data information are respectively input to a high-speed modulator. The high-speed modulator modulates the optical signals by phase or amplitude and outputs them to a polarization multiplexing module. The polarization multiplexing module controls the polarization of some or all of the optical signals and outputs them to a merging module. The merging module merges all the input optical signals and the local reference signal into one optical signal and outputs it to the optical fiber link.

[0036] The receiving end includes a wavelength division module, a coherent detection module, and a digital signal processing module connected in sequence. The wavelength division module receives the optical signal transmitted through the optical fiber link and separates the local reference optical signal and the data optical signal. The coherent detection module performs coherent detection on the data optical signal based on the local reference optical signal to obtain the data information.

[0037] in,

[0038] The detailed structure of the transmitter of this invention is as follows: Figure 2As shown, the system includes a laser source array and a high-speed interferometric modulation array connected in sequence. In the laser source array, some of the light emitted by the laser sources is used as a data channel to carry data information, and some is used to generate a local reference signal. That is, multiple data signals and one local reference signal are obtained from the laser source array. The data signals are modulated by a modulator and then polarization controlled separately. The local reference signal is filtered / attenuated to purify the optical spectrum and optimize the optical power matching. The polarization-controlled data signals and the filtered / attenuated local reference signals are combined by a merging module into one optical signal and output to the fiber optic link.

[0039] Specifically,

[0040] The laser source array in this invention:

[0041] (1) It contains at least N laser sources, one or more of which are used to carry data information, and the remaining one or more are used to generate local reference signals;

[0042] (2) The laser source array adopts an integrated coherent array laser or an independent laser array. An independent laser array is a light source array composed of multiple independent lasers, and the laser sources maintain frequency and phase synchronization.

[0043] (3) Supports dynamic frequency tuning function, which facilitates flexible wavelength allocation and wavelength division multiplexing;

[0044] (4) High-precision synchronization of each laser source in the laser source array is controlled by a phase-locked loop or optical phase-locked circuit.

[0045] (5) The laser source array integrates a thermoelectric modulation unit, which controls the temperature of the laser in the laser source array to achieve rapid wavelength stabilization.

[0046] The local reference signal in this invention:

[0047] The local reference signal generated by the transmitter through the laser in the laser source array or an independent laser source must be filtered and attenuated.

[0048] The high-speed modulator in this invention:

[0049] (1) A high-speed interferometric modulator array consisting of one or more high-speed interferometric modulators, each corresponding to one or more optical signals used to carry data information, receiving optical signals output from a laser source, and performing phase or amplitude modulation on the optical signals;

[0050] (2) The high-speed modulator is an interference structure based on thin-film lithium niobate, silicon photonics, indium phosphide or polymer materials. Preferably, its bandwidth is not less than 40 GHz, and some high-end models can reach more than 100 GHz. The interference structure can be selected from Mach-Zehnder interferometer, ring resonator and directional coupler, etc.

[0051] (3) Supports multiple modulation formats, including QPSK, QAM, DP-QPSK, DP-16QAM, DP-64QAM, etc.;

[0052] (4) Some high-speed modulators have built-in digital predistortion modules to compensate for nonlinear effects.

[0053] The polarization multiplexing module in this invention:

[0054] (1) The polarization multiplexing module is a flexible and optional module;

[0055] (2) Includes a polarization controller, a waveplate and a polarization beam splitter arranged in sequence to dynamically adjust the polarization state of the optical signal;

[0056] (3) Polarization control is applied to some or all of the modulated optical signals to achieve dual polarization modulation in order to improve channel capacity.

[0057] (4) Support the combined use of polarization multiplexing with wavelength division multiplexing, spatial multiplexing and other multidimensional multiplexing technologies.

[0058] The merging module in this invention:

[0059] (1) Use wavelength division multiplexer or spatial multiplexer to combine all data optical signals and local reference optical signals according to wavelength or spatial dimension;

[0060] (2) Combine the modulated multi-channel data optical signal with the local reference optical signal into a single optical signal and output it to the fiber optic link;

[0061] (3) It integrates functional units such as optical amplifiers, filters and isolators to improve signal integrity;

[0062] (4) Supports flexible wave combination mechanism, which can dynamically add new channels without affecting the operation of the existing system.

[0063] Furthermore,

[0064] The detailed structure of the receiver in this invention is as follows: Figure 3 As shown:

[0065] The wavelength division module has an optical fiber input interface at the front end, which connects to the optical fiber output interface of the merging module. The wavelength division module separates the optical signal input from the optical fiber link into multiple data optical signals and a local reference optical signal. The multiple data optical signals are input into a coherent detection module. The coherent detection module performs coherent detection on each data optical signal based on the local reference optical signal and outputs I / Q electrical signals. The I / Q electrical signals are processed by the data signal processing module (DSP) for equalization, adjustment, error correction, etc., to obtain multiple data and summarize them. Then, the AI-assisted demodulation module recovers the multiple data and outputs the data.

[0066] Specifically,

[0067] The receiving end in this invention:

[0068] (1) Includes a wavelength division module and a coherent detection module, used to separate the data optical signal from the local reference optical signal, and to perform coherent detection on the data optical signal based on the local reference optical signal;

[0069] (3) The wavelength division multiplexing module separates the optical signal through a wavelength division multiplexer or an optoelectronic hybrid filter. Further, such as... Figure 3 As shown, the data optical signal and the local reference optical signal are separated into multiple channels;

[0070] (2) The coherent detection module includes a 90° mixer and a balanced detector, such as Figure 3 As shown, coherent detection is performed on each data channel to output I / Q electrical signals. Coherent detection includes self-zero difference detection, heterodyne detection, or same-frequency zero difference detection, etc.

[0071] (4) Supports digital signal processing (DSP) algorithms for demodulation, equalization, error correction and other operations;

[0072] (5) An optional AI-assisted demodulation module can be installed to improve recovery capabilities under complex channels.

[0073] The local reference optical signal in this invention:

[0074] A local reference optical signal extraction unit is provided, which can extract the signal using zero difference and indicate the extraction path in the data channel.

[0075] The fiber optic link in this invention:

[0076] As an optical signal transmission medium, it connects the transmitter and receiver. Specifically, the receiver's wavelength division multiplexing module has an optical fiber input interface at the front end to receive multiplexed optical signals from the transmitter. Example 1:

[0077] The transmitter is equipped with a laser source array containing 64 laser channels and 8 local reference optical channels. Each laser channel is connected to a thin-film lithium niobate (MZI) modulator, with 32 channels undergoing dual-polarization modulation via a polarization multiplexing module. All modulated signals, along with the local reference optical signal, are then transmitted to the receiver via WDM multiplexing.

[0078] The receiver uses a coherent detector for self-zero error detection and a DSP for signal recovery, achieving a total transmission rate of 1024Tbps (1Pbps). Example 2:

[0079] The transmitter features a laser source array composed of multiple independent lasers, synchronized at frequency via a phase-locked circuit. The high-speed modulator is a Mach-Zehnder structure on a silicon photonics platform, supporting modulation bandwidths up to 100 GHz. The local reference signal is obtained by splitting a portion of the optical power from one of the data channels, followed by filtering and attenuation. The receiver employs heterodyne detection for signal demodulation and utilizes an AI demodulation module to improve bit error rate performance, enabling unlimited flexible scalability.

[0080] Advantages of this invention:

[0081] This invention relates to a multi-source integrated ultra-high-speed optical communication system using a side-emission coherent array laser. Through a multi-channel laser source, a high-speed modulator array, and an adaptive local reference optical path design, it achieves data transmission capabilities at the Pb / s level and even with no upper limit, while possessing core advantages such as high bandwidth, low bit error rate, and high integration. This system is suitable for ultra-high-speed optical communication scenarios such as data center interconnection, 6G fronthaul / midhaul / backhaul, metropolitan area networks, and backbone networks, and has broad market prospects and application value.

[0082] The communication system of this invention has ultra-high bandwidth, with a single modulator bandwidth of ≥ 40 GHz and up to 100 GHz, supporting Tb / s level single-channel rates; combined with multi-dimensional multiplexing (WDM, SDM, PolMux) combinations, it achieves Pb / s level total rates; the system design supports an infinitely expandable architecture, and theoretically there is no bandwidth limit.

[0083] The communication system of this invention has ultra-large capacity, supports multiple modulation formats (QPSK, QAM, DP-QAM, etc.) and multidimensional multiplexing, significantly improving spectrum efficiency; polarization multiplexing doubles the channel capacity, and WDM provides tens to hundreds of channels for parallel transmission; it supports a flexible expansion mechanism, which can increase the number of channels at any time according to service needs.

[0084] The communication system of this invention features a low bit error rate, with the local reference signal and data signal sharing the same source, reducing the impact of phase noise; coherent detection technology provides high sensitivity and anti-interference capability, significantly reducing the bit error rate; DSP and AI technologies assist demodulation, further improving signal recovery accuracy.

[0085] The communication system of this invention has a high degree of integration, and all modules can be implemented using integrated chips; it is particularly suitable for silicon photonics platforms or thin-film lithium niobate platforms, and supports large-scale production and deployment.

[0086] The communication system of this invention reduces dependence on external light sources, thereby reducing system complexity and maintenance costs; its highly integrated design reduces the number of components, thus lowering manufacturing costs; and it supports modular deployment, facilitating later maintenance and upgrades.

[0087] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser, characterized in that: Includes the transmitter and receiver; The transmitter includes a laser source array connected in sequence. The optical signal output by at least one laser source in the laser source array is used to carry data information, and the optical signal output by the remaining at least one laser source is used to generate a local reference signal. The laser sources in the laser source array are controlled to synchronize with high precision through a phase-locked loop or optical phase-locked circuit. All optical signals carrying data information are respectively input to a high-speed modulator. The high-speed modulator modulates the optical signals by phase or amplitude and outputs them to a polarization multiplexing module. The polarization multiplexing module controls the polarization of some or all of the optical signals and outputs them to a merging module. The local reference signal is transmitted separately to the merging module. The merging module merges all the input optical signals and the local reference signal into one optical signal and outputs it to the optical fiber link. The receiving end includes a wavelength division module, a coherent detection module, and a digital signal processing module connected in sequence. The wavelength division module receives the optical signal transmitted via the optical fiber link and separates the local reference optical signal and the data optical signal. The coherent detection module performs coherent detection on the data optical signal based on the local reference optical signal to obtain data information. The laser source array integrates a thermoelectric modulation unit, which controls the temperature of the laser in the laser source array to achieve rapid wavelength stabilization.

2. The multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser according to claim 1, characterized in that, The laser source array uses an integrated coherent array laser or a standalone laser array.

3. The multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser according to claim 1, characterized in that: The high-speed modulator is an interference-type structure based on thin-film lithium niobate, silicon photonics, indium phosphide, or polymer materials, including a Mach-Zehnder interferometer, a ring resonant cavity, and a directional coupler, with a bandwidth of not less than 40 GHz.

4. The multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser according to claim 1, characterized in that: The polarization multiplexing module includes a polarization controller, a waveplate, and a polarization beam splitter arranged in sequence to dynamically adjust the polarization state of the optical signal.

5. The multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser according to claim 1, characterized in that: The merging module employs a wavelength division multiplexer or a spatial multiplexer to merge all data optical signals and local reference signals according to wavelength or spatial dimension.

6. The multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser according to claim 1, characterized in that: The merging module integrates an optical amplifier, a filter, and an isolator.

7. The multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser according to claim 1, characterized in that: The coherent detection includes self-zero difference detection, heterodyne detection, or same-frequency zero difference detection.

8. The multi-source integrated ultra-high-speed optical communication system using a side-emitting coherent array laser according to claim 1, characterized in that: The wavelength division module separates the optical signal through a wavelength division multiplexer or an optoelectronic hybrid filter.

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