Signal processing chip system, channelized frequency measurement method and radio frequency selection method

Abstract

The invention provides a reconfigurable photon signal processing chip system which can be applied to the technical field of integrated photonics and microwave photonics. The chip system comprises: a continuous wave laser source for providing an optical carrier; the optical input end of the electro-optical modulator is used for receiving the optical carrier wave, and the radio frequency port of the electro-optical modulator is used for receiving a radio frequency signal to be processed; the tunable optical filter array comprises a plurality of micro-ring resonators which are connected in parallel, and each micro-ring resonator is configured to be provided with an independent tuning unit; the photoelectric detection array comprises a plurality of photoelectric detectors, the optical input end of each photoelectric detector is optically coupled with the downloading port of the corresponding micro-ring resonator, and the photoelectric detectors are used for converting the gated optical signals into electric signals and outputting the electric signals; wherein the electro-optical modulator, the tunable optical filter array and the photoelectric detection array are integrated on the same substrate.

Description

Technical Field

[0001] This invention relates to the fields of integrated photonics and microwave photonics, and more specifically to a reconfigurable photonic signal processing chip system, a channelized frequency measurement method, and a radio frequency selection method. Background Technology

[0002] In modern radar, electronic warfare, and broadband communication systems, extremely high demands are placed on the real-time spectrum analysis (i.e., channelized reception) and dynamic frequency selection routing capabilities of radio frequency signals in complex electromagnetic environments. Traditional solutions mainly rely on electronic technology or discrete optical components.

[0003] Channelized receiver schemes based on traditional electronic technology typically employ a large number of mixers, local oscillators, and electrical filter banks. When processing high-frequency, wideband signals, these schemes face serious electronic bottlenecks, such as limited instantaneous bandwidth, unavoidable electromagnetic interference, and inherent drawbacks like large system size and high power consumption.

[0004] To overcome the limitations of electronic technology, microwave photonics emerged. It leverages the advantages of photons, such as wide bandwidth, low transmission loss, and resistance to electromagnetic interference, providing a new approach to processing high-frequency broadband signals. Early microwave photonic systems were constructed from discrete optical components (such as modulators, optical fibers, bulk optical filters, and discrete detectors) on an optical platform. Although these systems exhibited excellent bandwidth performance, they were bulky, complex, expensive, and sensitive to environmental vibrations and temperature changes, exhibiting poor stability and failing to meet the requirements of modern electronic systems for miniaturization, high reliability, and low cost.

[0005] In recent years, the maturity of silicon-based photonic integration technology has provided an ideal platform for solving the above problems. This technology can integrate multiple optical components on a single chip with high density, significantly reducing system size, improving stability, and lowering costs. Existing technologies have proposed schemes using integrated microring resonators for optical filtering and switching. However, these schemes typically have two main limitations: first, their functions are relatively limited, lacking the ability to dynamically reconfigure multiple functions (such as channelized reception and frequency-selective switching) through electrical control on the same hardware platform; second, these schemes usually fail to integrate key photodetector functions monolithically, still relying on off-chip discrete photodetectors. This "partial integration" approach introduces additional optical coupling losses, packaging complexity, and cost between the chip and the detector, while also limiting the overall system bandwidth, response speed, and reliability. Summary of the Invention

[0006] (a) Technical problems to be solved

[0007] To address at least one of the aforementioned problems, this invention provides a reconfigurable photonic signal processing chip system, a channelized frequency measurement method, and a radio frequency selection method. By monolithically integrating an electro-optic modulator, a tunable optical filter array based on multiple parallel microring resonators, and a photodetector array onto a single substrate, and independently tuning the resonant wavelength of each microring, dynamic switching between a channelized reception mode (for parallel spectrum sensing) and a radio frequency selection switching mode (for dynamic frequency routing) is achieved. This solution, through high integration and functional reconfigurability, overcomes the shortcomings of traditional discrete optical systems, such as large size and poor stability, as well as the limited functionality of existing integrated solutions. Ultimately, it achieves a comprehensive advantage of miniaturization, high performance (high speed, wideband processing, high sensitivity), excellent flexibility, and easy scalability, providing an efficient chip-level wideband radio frequency signal processing solution for modern radar, electronic warfare, and other systems.

[0008] (II) Technical Solution

[0009] To address the aforementioned technical problems, embodiments of the present invention propose a reconfigurable photonic signal processing chip system, a channelized frequency measurement method, and a radio frequency selection method.

[0010] According to a first aspect of the present invention, a reconfigurable photonic signal processing chip system is provided, comprising: a continuous-wave laser source for providing an optical carrier; an electro-optic modulator, wherein the optical input terminal of the electro-optic modulator is used to receive the optical carrier, and the radio frequency port of the electro-optic modulator is used to receive a radio frequency signal to be processed; a tunable optical filter array comprising a plurality of parallel microring resonators, each microring resonator being configured to have an independent tuning unit; and a photodetector array comprising a plurality of photodetectors, wherein the optical input terminal of each photodetector is optically coupled to the download port of a corresponding microring resonator for converting the selected optical signal into an electrical signal output; wherein the electro-optic modulator, the tunable optical filter array, and the photodetector array are integrated on the same substrate.

[0011] In some exemplary embodiments, the system is configured to dynamically switch between at least two operating modes by controlling the tuning unit: a channelized receive mode, in which each microring resonator is tuned to a specific sub-band within the operating frequency band to achieve parallel spectrum sensing of the input RF signal; and a frequency selection switch mode, in which each microring resonator is tuned to selectively download specific target frequency components from the input RF signal and route them to a designated photodetector output.

[0012] In some exemplary embodiments, the tuning unit is a thermo-optical tuner, and the tuning range of the tuning unit covers at least the free spectral range of a microring resonator.

[0013] In some exemplary embodiments, in channelized reception mode, multiple microring resonators are tuned to multiple non-overlapping sub-bands covering the operating frequency band.

[0014] In some exemplary embodiments, in frequency selection switch mode, the system is configured to dynamically route multiple different frequency components in the input composite radio frequency signal to the same or different output ports in the photodetector array by tuning.

[0015] In some exemplary embodiments, the system further includes a control module configured to generate control signals to drive the tuning unit based on received external commands or feedback signals from the photodetector array, thereby enabling automatic switching of operating modes or dynamic reconfiguration of filter states.

[0016] In some exemplary embodiments, the number of microring resonators in the tunable optical filter array is greater than the number of photodetectors in the photodetector array, and the system is configured to activate different groups of microring resonators to an operating state at different times via a tuning unit to extend the effective processing bandwidth or frequency resolution of the system.

[0017] In some exemplary embodiments, the continuous wave laser source is a stand-alone laser located outside the substrate.

[0018] According to a second aspect of the present invention, a channelized frequency measurement method based on the above-described reconfigurable photonic signal processing chip system is provided, comprising: tuning each micro-ring resonator in a tunable optical filter array to a predetermined sub-band within a target frequency band; inputting the radio frequency signal to be measured to an electro-optic modulator; reading the output signals of each detector in a photodetector array in parallel; and determining the spectral components of the radio frequency signal to be measured based on the output signals of the photodetector array.

[0019] According to a third aspect of the present invention, a radio frequency selection method based on the above-described reconfigurable photonic signal processing chip system is provided, comprising: inputting a composite radio frequency signal to be processed into an electro-optic modulator; tuning a specific filter in a tunable optical filter array to a resonant state corresponding to a target radio frequency frequency component according to a target routing scheme, while simultaneously detuning other filters; and acquiring an electrical signal of the target radio frequency frequency component from the output terminal of a photodetector corresponding to the filter in the resonant state.

[0020] (III) Beneficial Effects

[0021] As can be seen from the above technical solutions, the reconfigurable photonic signal processing chip system, channelized frequency measurement, and radio frequency selection method provided by the embodiments of the present invention have at least the following beneficial effects:

[0022] (1) A true monolithic fully integrated system: For the first time, a high-speed electro-optic modulator, a tunable micro-ring filter array, and a high-speed photodetector are fully integrated into a single silicon-based chip, forming a complete on-chip signal processing system. This eliminates coupling loss, alignment problems, and instability between the chip, fiber, and detector, significantly improving the system's reliability, bandwidth performance, and compactness.

[0023] (2) High speed and high sensitivity: The chip-integrated detector directly receives the download optical signal from the micro ring, avoiding the delay and additional insertion loss of external reception, supporting higher speed real-time signal processing, and improving the receiving sensitivity of the system.

[0024] (3) Dual-function dynamic reconfiguration: Through simple electrothermal tuning, it is possible to flexibly and quickly switch between the two functions of channelized receiver and RF frequency selection switch, or dynamically reconfigure the channel allocation and routing scheme within each mode. The system is highly adaptable and has a wide range of applications.

[0025] (4) Easy to manufacture and scale up: Based on CMOS compatible technology, all components can be fabricated using standard semiconductor processes, resulting in low cost, high yield, and good consistency. The channel capacity and processing power of the system can be linearly expanded by increasing the number of parallel micro-rings and detector units. Attached Figure Description

[0026] The above-described features, other objects, and advantages of the present invention will become clearer from the following description of embodiments of the invention with reference to the accompanying drawings, in which:

[0027] Figure 1 The schematic diagram illustrates the structure of a reconfigurable photonic signal processing chip system according to an embodiment of the present invention.

[0028] Figure 2 A flowchart illustrating a channelized frequency measurement method according to an embodiment of the present invention is shown schematically;

[0029] Figure 3 A flowchart illustrating a radio frequency selection method according to an embodiment of the present invention is shown schematically.

[0030] Figure label:

[0031] 101 - Continuous wave laser source; 102 - Electro-optic modulator; 103 - Tunable optical filter array; 104 - Photodetector array; MR1 - First microring resonator; MR2 - Second microring resonator; MR3 - Third microring resonator; MR4 - Fourth microring resonator; 104-1 - First photodetector; 104-2 - Second photodetector; 104-3 - Third photodetector; and 104-4 - Fourth photodetector. Detailed Implementation

[0032] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the invention. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the invention for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0033] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The terms “comprising,” “including,” etc., as used herein indicate the presence of features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0034] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0035] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0036] Figure 1 The schematic diagram illustrates the structure of a reconfigurable photonic signal processing chip system according to an embodiment of the present invention.

[0037] like Figure 1As shown, a reconfigurable photonic signal processing chip system according to an embodiment of the present invention includes: a continuous-wave laser source 101 for providing an optical carrier; an electro-optic modulator 102, the optical input terminal of which is used to receive the optical carrier, and the radio frequency port of which is used to receive the radio frequency signal to be processed; a tunable optical filter array 103, including multiple parallel micro-ring resonators, each micro-ring resonator being configured with an independent tuning unit; and a photodetector array 104, including multiple photodetectors, the optical input terminal of each photodetector being optically coupled to the download port of a corresponding micro-ring resonator, for converting the selected optical signal into an electrical signal output; wherein the electro-optic modulator 102, the tunable optical filter array 103, and the photodetector array 104 are integrated on the same substrate; and the continuous-wave laser source 101 is an independent laser located outside the substrate. This design, which monolithically integrates the core functional units, brings significant advantages such as small size, high link stability, large bandwidth, and low loss, completely solving the problems of large size, difficult alignment, and poor stability existing in traditional discrete optical systems.

[0038] In embodiments of the present invention, the system is configured to dynamically switch between at least two operating modes by controlling a tuning unit: a channelized reception mode, in which each microring resonator is tuned to a specific sub-band within the operating frequency band that is different from each other, to achieve parallel spectrum sensing of the input radio frequency signal; and a frequency selection switching mode, in which each microring resonator is tuned to selectively download specific target frequency components in the input radio frequency signal and route them to a designated photodetector output. In the channelized reception mode, multiple microring resonators are tuned to multiple non-overlapping sub-bands covering the operating frequency band. In the frequency selection switching mode, the system is configured to dynamically route multiple different frequency components in the input composite radio frequency signal to the same or different output ports in the photodetector array 104 through tuning. In the channelized reception mode, each microring is tuned to a specific non-overlapping sub-band within the operating frequency band that is different from each other, thereby achieving parallel spectrum sensing of the input radio frequency signal. Its beneficial effect is that it enables high-speed, parallel analysis of the signal spectrum, rapid determination of the frequency components contained in the signal, and greatly improves the efficiency of spectrum analysis. In frequency selection switch mode, the system is configured to selectively download specific target frequency components from the input composite RF signal and dynamically route them to the designated photodetector output. This allows the system to function like a programmable switch, enabling dynamic connections from any frequency to any port in the frequency domain, providing powerful signal routing and filtering capabilities. This dual-mode functionality allows a single chip to adapt to various application scenarios, from spectrum detection to signal routing, offering flexibility and a wide range of applications.

[0039] In an embodiment of the present invention, the tuning unit is a thermo-optical tuner, and the tuning range of the tuning unit covers at least the free spectral range of a micro-ring resonator. By changing the refractive index of the micro-ring waveguide through thermal effects, its resonant wavelength is precisely controlled, ensuring that the tuning range can cover the entire operating frequency band without frequency dead zones. At the same time, thermo-optical tuning technology is mature, precise in control, and fully compatible with CMOS processes, which is beneficial for manufacturing.

[0040] In embodiments of the present invention, the system further includes a control module configured to generate control signals to drive the tuning unit based on received external commands or feedback signals from the photoelectric detection array 104, thereby enabling automatic switching of operating modes or dynamic reconfiguration of filter states. This significantly reduces the need for manual intervention, allowing the system to adapt to environmental changes or task requirements, and enhancing its reliability and practicality in complex scenarios.

[0041] In embodiments of the present invention, the number of microring resonators in the tunable optical filter array 103 is greater than the number of photodetectors in the photodetector array 104, and the system is configured to activate different groups of microring resonators to an operational state at different times via a tuning unit, thereby expanding the system's effective processing bandwidth or frequency resolution. By designing the number of microring resonators in the tunable optical filter array 103 to be greater than the number of photodetectors, the system can activate different groups of microring resonators at different times via the tuning unit, i.e., employing the time multiplexing principle. This means that without increasing the number of costly detectors, the system's processing bandwidth or frequency resolution can be effectively expanded simply through a flexible tuning strategy. This design optimizes hardware resources, reduces costs, and gives the system greater functional flexibility and performance potential.

[0042] Figure 2 A flowchart illustrating a channelized frequency measurement method according to an embodiment of the present invention is shown schematically.

[0043] like Figure 2 As shown, a channelized frequency measurement method according to an embodiment of the present invention includes steps S110 to S140.

[0044] In step S110, each microring resonator in the tunable optical filter array 103 is tuned to a predetermined sub-band within the target frequency band.

[0045] In step S120, the radio frequency signal to be tested is input to the electro-optic modulator 102.

[0046] In step S130, the output signals of each detector in the photoelectric detection array 104 are read in parallel.

[0047] In step S140, the spectral components of the radio frequency signal under test are determined based on the output signal of the photoelectric detection array 104.

[0048] For example: Figure 1 The high-speed reconfigurable channelized receiver and RF frequency selection switch chip with integrated detector shown includes: a continuous wave laser source 101 located outside the chip; an electro-optic modulator 102 integrated on a silicon-based chip; a tunable optical filter array 103 including four parallel upload / download microring resonators, namely a first microring resonator MR1, a second microring resonator MR2, a third microring resonator MR3, and a fourth microring resonator MR4; and a photodetector array 104 including four silicon-germanium photodetectors, namely a first photodetector 104-1, a second photodetector 104-2, a third photodetector 104-3, and a fourth photodetector 104-4. When operating in channelized frequency measurement mode, different electrical powers are applied to the heaters of the four microring resonators through a control circuit, causing the resonant wavelengths of the four microring resonators to redshift relative to the initial wavelength λ, respectively, precisely corresponding to RF frequencies f1 = X / 8, f2 = 3X / 8, f3 = 5X / 8, and f4 = 7X / 8 GHz. In this way, the four micro-rings uniformly cover the 0-X GHz frequency band. An unknown RF signal with a bandwidth of 0-X GHz is input to the RF port. After being modulated onto an optical carrier, the signal is transmitted in the optical waveguide. Each micro-ring will download the RF sideband corresponding to its resonant frequency. For example, if the input signal mainly contains components near frequency f2, the second photodetector 104-2 corresponding to the second micro-ring resonator MR2 at frequency f2 will output a significant electrical signal, while the outputs of other detectors will be weak or zero. By monitoring the outputs of the four detectors, the spectral components of the input signal can be determined in real time.

[0049] Figure 3 A flowchart illustrating a radio frequency selection method according to an embodiment of the present invention is shown schematically.

[0050] like Figure 3 As shown, a radio frequency selection method according to an embodiment of the present invention includes steps S210 to S230.

[0051] In step S210, the composite radio frequency signal to be processed is input to the electro-optic modulator 102.

[0052] In step S220, according to the target routing scheme, a specific filter in the tunable optical filter array 103 is tuned to a resonant state corresponding to the target radio frequency frequency component, while other filters are detuned.

[0053] In step S230, an electrical signal of the target radio frequency frequency component is obtained from the output terminal of the photodetector corresponding to the filter in the resonant state.

[0054] For example, when Figure 1 The high-speed reconfigurable channelized receiver and RF frequency selective switch chip shown, operating in RF frequency selective switch mode, receives a composite RF signal containing two components with frequencies of f_A = X / 4 GHz and f_B = 3X / 4 GHz from the RF port. The system task is to route f_A to the output of the first photodetector 104-1 and f_B to the output of the third photodetector 104-3. Tuning: The thermal tuner of the first micro-ring resonator MR1 is controlled to precisely align its resonant wavelength with f_A; the thermal tuner of the third micro-ring resonator MR3 is controlled to precisely align its resonant wavelength with f_B. Simultaneously, the second micro-ring resonator MR2 and the fourth micro-ring resonator MR4 are detuned (e.g., by turning off their heaters or applying a reverse bias voltage to move their resonant wavelengths away from the signal band). Routing: The signal light carrying f_A is efficiently downloaded by MR1 and received by the subsequent detector 104-1, which converts it into an electrical signal. The signal light carrying f_B is downloaded by the first microring resonator MR1, received by the third photodetector 104-3, and converted into an electrical signal. Reconfiguration: If a change in routing is needed, for example, to download f_A and f_B to the second microring resonator MR2 and the fourth microring resonator MR4, simply align the second microring resonator MR2 and the fourth microring resonator MR4 with f_A and f_B respectively through thermal tuning, while simultaneously detuning the first microring resonator MR1 and the third microring resonator MR3. This system achieves dynamic, reconfigurable switching and routing of radio frequency components.

[0055] Those skilled in the art will understand that the features described in the various embodiments of the present invention can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in the present invention. In particular, the features described in the various embodiments of the present invention can be combined and / or combined in various ways without departing from the spirit and teachings of the present invention. All such combinations and / or combinations fall within the scope of the present invention.

Claims

1. A reconfigurable photonic signal processing chip system, characterized in that, include: A continuous wave laser source is used to provide an optical carrier. An electro-optic modulator, wherein the optical input terminal of the electro-optic modulator is used to receive the optical carrier, and the radio frequency port of the electro-optic modulator is used to receive the radio frequency signal to be processed; A tunable optical filter array includes multiple parallel microring resonators, each of which is configured to have an independent tuning unit; The photoelectric detection array includes multiple photodetectors, and the optical input terminal of each photodetector is optically coupled to the download port of a corresponding microring resonator to convert the selected optical signal into an electrical signal output. The electro-optic modulator, the tunable optical filter array, and the photodetector array are integrated on the same substrate.

2. The reconfigurable photonic signal processing chip system according to claim 1, characterized in that, The system is configured to dynamically switch between at least two operating modes by controlling the tuning unit: In the channelized reception mode, each micro-ring resonator is tuned to a specific sub-band that is different from each other within the operating frequency band to achieve parallel spectrum sensing of the input RF signal. In frequency-selective switching mode, each microring resonator is tuned to selectively download a specific target frequency component from the input RF signal and route it to the output of a designated photodetector.

3. The reconfigurable photonic signal processing chip system according to claim 1, characterized in that, The tuning unit is a thermo-optical tuner, and the tuning range of the tuning unit covers at least the free spectral range of a microring resonator.

4. The reconfigurable photonic signal processing chip system according to claim 2, characterized in that, In the channelized reception mode, the plurality of micro-ring resonators are tuned to a plurality of sub-bands that cover the operating frequency band and do not overlap with each other.

5. The reconfigurable photonic signal processing chip system according to claim 2, characterized in that, In the frequency selection switch mode, the system is configured to dynamically route multiple different frequency components in the input composite radio frequency signal to the same or different output ports in the photodetector array through tuning.

6. The reconfigurable photonic signal processing chip system according to claim 1, characterized in that, The system also includes a control module, which is configured to generate control signals based on received external commands or feedback signals from the photoelectric detection array to drive the tuning unit, thereby enabling automatic switching of operating modes or dynamic reconfiguration of filter states.

7. The reconfigurable photonic signal processing chip system according to claim 1, characterized in that, The number of microring resonators in the tunable optical filter array is greater than the number of photodetectors in the photodetector array, and the system is configured to activate different groups of microring resonators to the working state at different times through the tuning unit, so as to extend the effective processing bandwidth or frequency resolution of the system.

8. The reconfigurable photonic signal processing chip system according to claim 1, characterized in that, The continuous wave laser source is an independent laser located outside the substrate.

9. A channelized frequency measurement method, characterized in that, Using the reconfigurable photonic signal processing chip system as described in any one of claims 1-8, the method comprises: Each microring resonator in the tunable optical filter array is tuned to a predetermined sub-band within the target frequency band; The radio frequency signal to be tested is input to the electro-optic modulator; The output signals of each detector in the photoelectric detection array are read in parallel. Based on the output signal of the photoelectric detection array, the spectral components of the radio frequency signal under test are determined.

10. A radio frequency selection method, characterized in that, Using the reconfigurable photonic signal processing chip system as described in any one of claims 1-8, the method comprises: The composite radio frequency signal to be processed is input into the electro-optic modulator; According to the target routing scheme, a specific filter in the tunable optical filter array is tuned to a resonant state corresponding to the target radio frequency frequency component, while other filters are detuned. The electrical signal of the target radio frequency frequency component is obtained from the output terminal of the photodetector corresponding to the filter in a resonant state.

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