Wireless signal generation apparatus and method based on integrated optical comb synchronization

Abstract

The application provides a wireless signal generation device and method based on integrated optical comb synchronization. The device comprises: an integrated optical comb repetition frequency signal generation unit: generating an optical comb signal, filtering the optical comb signal to obtain first and second optical signals adjacent to the beam, and third and fourth optical signals with different frequencies, and obtaining a high-frequency clock signal with the same frequency as the optical comb signal by combining, amplifying and frequency mixing the first and second optical signals; a standard microwave clock signal generation unit: after amplification and filtering of the high-frequency clock signal, the microwave clock signal with a standard frequency and synchronized with the high-frequency clock signal is obtained by integer frequency division and decimal frequency division in turn; a wireless signal generation unit: converting the microwave clock signal into a low-frequency baseband signal, generating an optical carrier microwave signal by single sideband modulation of the fourth optical signal through the low-frequency baseband signal, and obtaining a high-frequency coherent wireless signal by combining and frequency mixing the optical carrier microwave signal and the third optical signal.

Description

Technical Field

[0001] This invention relates to the fields of wireless communication and sensing imaging, and in particular to a wireless signal generation device and method based on integrated optical comb synchronization. Background Technology

[0002] In the future, 6G networks will provide ultra-high-speed data transmission exceeding 1Tbps, dozens of times faster than existing 5G technology, meeting the demands of high-bandwidth applications such as AR, VR, haptic internet, and holographic experiences. Simultaneously, 6G will also need to achieve centimeter-level precision sensing technology to support applications in fields such as extended reality, intelligent transportation, and healthcare.

[0003] However, traditional electronic wireless communication systems are limited by electronic bottlenecks, restricting their operating frequency and bandwidth. Photonic-assisted technologies, especially photonic upconversion technology, with their ultra-wideband millimeter-wave and terahertz signal processing capabilities, have opened up new directions for high-frequency communication and radar systems. Optical comb technology has achieved significant results in the fields of wireless sensing and communication, but existing electro-optical comb systems rely on high-frequency microwave sources, resulting in high costs.

[0004] With advancements in micro-nano fabrication technology, the emergence and control of novel optical comb systems have made miniaturized, low-power integrated optical comb systems possible, offering significant advantages in photonic-assisted wireless communication sensing systems. However, achieving clock synchronization between the optical comb system and the electronic system still requires overcoming technical challenges such as the complexity and operational difficulties of traditional electrical locking architectures. Summary of the Invention

[0005] In view of the above problems, the present invention provides a wireless signal generation device and method based on integrated optical comb synchronization, which at least partially solves the above technical problems.

[0006] The first aspect of the present invention provides a wireless signal generation device based on integrated optical comb synchronization, comprising: an integrated optical comb repetition frequency signal generation unit for generating an optical comb signal, filtering the optical comb signal to obtain a first single-frequency optical signal and a second single-frequency optical signal with adjacent beams, and a third single-frequency optical signal and a fourth single-frequency optical signal with different frequencies, and combining, amplifying and beating the first single-frequency optical signal and the second single-frequency optical signal to obtain a high-frequency clock signal with the same frequency as the optical comb signal; a standard microwave clock signal generation unit for amplifying and filtering the high-frequency clock signal, and then sequentially dividing it by integer frequency and fractional frequency to obtain a microwave clock signal with a standard frequency synchronized with the high-frequency clock signal; and a wireless signal generation unit for converting the microwave clock signal into a low-frequency baseband signal, performing single-sideband modulation on the fourth single-frequency optical signal using the low-frequency baseband signal to generate an optically carried microwave signal, and combining the optically carried microwave signal and the third single-frequency optical signal to obtain a high-frequency coherent wireless signal.

[0007] According to an embodiment of the present invention, the integrated optical comb repetition rate signal generation unit includes a distributed feedback laser, a high-quality factor silicon nitride microring, a multi-channel tunable optical filter, a first optical coupler, a first optical amplifier, and a first photodetector connected in sequence. The distributed feedback laser generates pump light, which is self-injected and locked into the high-quality factor silicon nitride microring to generate an optical comb signal. The multi-channel tunable optical filter filters and selects the comb teeth of the optical comb signal to obtain a first single-frequency optical signal and a second single-frequency optical signal with adjacent beams, as well as a third single-frequency optical signal and a fourth single-frequency optical signal with different frequencies. The first optical coupler combines the first single-frequency optical signal and the second single-frequency optical signal to obtain a first combined signal. The first combined signal is amplified by the first optical amplifier and then enters the first photodetector to obtain a high-frequency clock signal with the same frequency as the optical comb signal.

[0008] According to an embodiment of the present invention, a distributed feedback laser and a high-quality factor silicon nitride microring are integrated on the same optical chip.

[0009] According to an embodiment of the present invention, the standard microwave clock signal generation unit includes a radio frequency amplifier, a radio frequency filter, a radio frequency integer divider, and a radio frequency fractional divider connected in sequence. The radio frequency amplifier amplifies the power of the high-frequency clock signal. After the amplified high-frequency clock signal is filtered by the radio frequency filter, it is divided by the radio frequency integer divider to obtain a low-frequency signal with a frequency of 1 / N of the high-frequency clock signal, where N is a positive integer. The low-frequency signal is converted to a standard frequency microwave clock signal by the radio frequency fractional divider.

[0010] According to an embodiment of the present invention, the wireless signal generation unit includes: a first optical polarization controller and a second optical polarization controller, respectively used to control the polarization states of a third single-frequency optical signal and a fourth single-frequency optical signal; a second optical amplifier and a third optical amplifier, respectively used to amplify the power of the polarization-controlled third single-frequency optical signal and the fourth single-frequency optical signal; and an arbitrary waveform generator, an RF bridge, a single-sideband modulation module, a second optical coupler, and a second photodetector connected in sequence, wherein: the arbitrary waveform generator generates a low-frequency baseband signal based on a received microwave clock signal; the low-frequency baseband signal is split into two electrical signals by the RF bridge; the single-sideband modulation module performs carrier-suppressed single-sideband modulation on the power-amplified fourth single-frequency optical signal through the two electrical signals to obtain an optical microwave signal; the second optical coupler combines the optical microwave signal and the power-amplified third single-frequency optical signal to obtain a second combined signal, and the second combined signal enters the second photodetector for power detection to obtain a wireless signal.

[0011] According to an embodiment of the present invention, the radio frequency bridge is a radio frequency 90° bridge, used to split the low-frequency baseband signal into a first electrical signal and a second electrical signal with a 90° phase difference.

[0012] According to an embodiment of the present invention, the standard frequency is 10MHz or 100MHz.

[0013] A second aspect of the present invention provides a method for generating wireless signals based on integrated optical comb synchronization, comprising: generating an optical comb signal; filtering the optical comb signal to obtain a first single-frequency optical signal and a second single-frequency optical signal with adjacent beams, and a third single-frequency optical signal and a fourth single-frequency optical signal with different frequencies; combining, amplifying, and beating the first and second single-frequency optical signals to obtain a high-frequency clock signal with the same frequency as the optical comb signal; amplifying and filtering the high-frequency clock signal, and then sequentially dividing it by integer and fractional frequencies to obtain a microwave clock signal with a standard frequency synchronized with the high-frequency clock signal; converting the microwave clock signal into a low-frequency baseband signal; performing single-sideband modulation on the fourth single-frequency optical signal using the low-frequency baseband signal to generate an optically carried microwave signal; and combining the optically carried microwave signal and the third single-frequency optical signal to obtain a high-frequency coherent wireless signal.

[0014] According to an embodiment of the present invention, generating an optical comb signal includes: generating pump light through a distributed feedback laser, self-injecting and locking the pump light into a high-quality factor silicon nitride microring to generate an optical comb signal, wherein the distributed feedback laser and the high-quality factor silicon nitride microring are integrated on the same optical chip.

[0015] According to an embodiment of the present invention, a fourth single-frequency optical signal is modulated by a low-frequency baseband signal using a single-sideband modulation to generate an optical microwave signal. The optical microwave signal and the third single-frequency optical signal are then combined and beat-frequency-controlled to obtain a high-frequency coherent wireless signal. The method includes: controlling the polarization states of the third and fourth single-frequency optical signals using a first and a second optical polarization controller, respectively; amplifying the polarization-controlled third and fourth single-frequency optical signals using a second and a third optical amplifier, respectively; splitting the low-frequency baseband signal into two electrical signals using an RF bridge; performing carrier-suppressed single-sideband modulation on the amplified fourth single-frequency optical signal using a single-sideband modulation module based on the two electrical signals to obtain the optical microwave signal; and combining the optical microwave signal and the amplified third single-frequency optical signal using a second optical coupler to obtain a second combined signal.

[0016] Compared with the prior art, the wireless signal generation device and method based on integrated optical comb synchronization provided by the present invention has at least the following technical effects:

[0017] (1) The optical comb signal is generated by using an on-chip distributed feedback laser and an on-chip high-quality factor silicon nitride microring, resulting in high light source integration. The principle of self-injection locking to narrow linewidth is utilized to obtain a high-quality microcavity optical comb.

[0018] (2) The scheme of dividing the high-frequency clock signal with the same frequency as the optical comb signal to the standard microwave clock frequency and using it as the synchronization clock of the entire optoelectronic system is proposed. Since the high-frequency clock signal has great potential in achieving ultra-low phase noise performance, using it as the clock signal can improve the overall optoelectronic system parameter level.

[0019] (3) By utilizing the high coherence of the optical comb teeth and the carrier suppression single-sideband modulation of the IQ modulator, the tunability of the output electrical signal is ensured, and various signals (such as single-frequency signals, Chirp signals, QPSK signals, etc.) can be tuned.

[0020] (4) The device link structure is simple and easy to operate, which reduces the complexity of hardware and is easy to miniaturize and integrate. Attached Figure Description

[0021] The above and other objects, features and advantages of the present invention will become more apparent from the following description of embodiments of the invention with reference to the accompanying drawings, in which:

[0022] Figure 1 This schematic diagram illustrates the structure of a wireless signal generation device based on integrated optical comb synchronization according to an embodiment of the present invention.

[0023] Figure 2 A flowchart illustrating a wireless signal generation method based on integrated optical comb synchronization according to an embodiment of the present invention is shown.

[0024] Explanation of reference numerals in the attached figures:

[0025] OC - ​​Optical comb signal; OC1 - First single-frequency optical signal; OC2 - Second single-frequency optical signal; OC3 - Third single-frequency optical signal; OC4 - Fourth single-frequency optical signal; OC12 - First beam combiner signal; E - High-frequency clock signal; E2 - Low-frequency signal; Ref - Microwave clock signal; IF - Low-frequency baseband signal; IF1 - First electrical signal; IF2 - Second electrical signal; OC5 - Optical microwave signal; OC35 - Second beam combiner signal; ET - Wireless signal. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0027] 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 the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0028] 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.

[0029] Figure 1 The diagram illustrates the structure of a wireless signal generation device based on integrated optical comb synchronization according to an embodiment of the present invention.

[0030] like Figure 1 As shown, the wireless signal generation device based on integrated optical comb synchronization in this embodiment includes:

[0031] An integrated optical comb repetition frequency signal generation unit is used to generate an optical comb signal OC. The optical comb signal OC is filtered to obtain a first single-frequency optical signal OC1 and a second single-frequency optical signal OC2 with adjacent beams, as well as a third single-frequency optical signal OC3 and a fourth single-frequency optical signal OC4 with different frequencies. The first single-frequency optical signal OC1 and the second single-frequency optical signal OC2 are combined, amplified and beat frequencyd to obtain a high-frequency clock signal E with the same frequency as the optical comb signal OC.

[0032] The standard microwave clock signal generation unit is used to amplify and filter the high-frequency clock signal E, and then successively divide it by integer and fractional frequencies to obtain a microwave clock signal Ref with a standard frequency that is synchronized with the high-frequency clock signal E.

[0033] The wireless signal generation unit is used to convert the microwave clock signal Ref into a low-frequency baseband signal IF, and to perform single-sideband modulation on the fourth single-frequency optical signal OC4 through the low-frequency baseband signal IF to generate an optical microwave signal OC5. The optical microwave signal OC5 and the third single-frequency optical signal OC3 are combined and beat frequency is applied to obtain a high-frequency coherent wireless signal ET.

[0034] The following will be based on Figure 1 The structure is described in detail, including the integrated optical comb repetition frequency signal generation unit, the standard microwave clock signal generation unit, and the wireless signal generation unit.

[0035] In this embodiment, the integrated optical comb repetition rate signal generation unit includes a distributed feedback laser, a high-quality factor (Q-value) silicon nitride microring, a multi-channel tunable optical filter, a first optical coupler, a first optical amplifier, and a first photodetector connected in sequence, wherein:

[0036] A distributed feedback laser generates pump light, which is self-injected and locked into a high-quality factor silicon nitride microring to generate an optical comb signal OC.

[0037] The multi-channel tunable optical filter filters and selects the comb teeth of the optical comb signal OC to obtain the first single-frequency optical signal OC1 and the second single-frequency optical signal OC2 with adjacent beams, as well as the third single-frequency optical signal OC3 and the fourth single-frequency optical signal OC4 with different frequencies.

[0038] The first optical coupler combines the first single-frequency optical signal OC1 and the second single-frequency optical signal OC2 to obtain the first combined signal OC12. The first combined signal OC12 is amplified by the first optical amplifier and then enters the first photodetector. At the output of the first photodetector, a high-frequency clock signal E with the same frequency as the optical comb signal OC is obtained.

[0039] Preferably, the distributed feedback laser and the high-quality factor silicon nitride microring are integrated on the same optical chip. That is, the distributed feedback laser can be an on-chip distributed feedback laser, and the high-quality factor silicon nitride microring can be an on-chip high-quality factor silicon nitride microring.

[0040] Understandably, high-quality silicon nitride microrings can provide accumulated backscattered Rayleigh light feedback. By integrating them with a distributed feedback semiconductor laser, an optical comb signal (OC) can be obtained, serving as a highly integrated, self-injection-locked, on-chip narrow-linewidth light source. This improves integration and makes them suitable for high-speed communication and optical sensing applications.

[0041] In this way, the integrated optical comb repetition frequency signal generation unit can generate the repetition frequency signal of the integrated optical comb, which is used as a high-frequency clock signal E. Among them, the third single-frequency optical signal OC3 and the fourth single-frequency optical signal OC4 enter the wireless signal generation unit as optical carriers to provide beat frequency for generating high-frequency wireless signals.

[0042] In this embodiment, the standard microwave clock signal generation unit includes a radio frequency amplifier, a radio frequency filter, a radio frequency integer divider, and a radio frequency fractional divider connected in sequence, wherein:

[0043] The RF amplifier amplifies the power of the high-frequency clock signal E. After the amplified high-frequency clock signal E is filtered by the RF filter, it is divided into integers by the RF integer divider to obtain a low-frequency signal E2 with a frequency of 1 / N of the high-frequency clock signal, where N is a positive integer.

[0044] The low-frequency signal E2 is converted to a standard frequency microwave clock signal Ref using an RF fractional divider.

[0045] For example, an RF amplifier connected to the output of the first photodetector in the integrated optical comb repetition rate signal generation unit can amplify the high-frequency clock signal E. An RF filter then filters the amplified high-frequency clock signal E, making it cleaner.

[0046] For example, the standard frequency is 10MHz or 100MHz. Therefore, the RF fractional divider can convert the low-frequency signal E2 to a standard 10MHz or 100MHz microwave clock signal Ref.

[0047] In this way, the standard microwave clock signal generation unit can generate a standard frequency microwave clock signal Ref, which is synchronized with the high-frequency clock signal E.

[0048] In this embodiment, the wireless signal generating unit includes:

[0049] The first optical polarization controller and the second optical polarization controller are used to control the polarization states of the third single-frequency optical signal OC3 and the fourth single-frequency optical signal OC4, respectively.

[0050] The second and third optical amplifiers are used to amplify the power of the polarization-controlled third single-frequency optical signal OC3 and the fourth single-frequency optical signal OC4, respectively.

[0051] An arbitrary waveform generator, an RF bridge, a single-sideband modulation module, a second optical coupler, and a second photodetector are connected in sequence. The second optical amplifier is connected to the second optical coupler, and the third optical amplifier is connected to the single-sideband modulation module.

[0052] The arbitrary waveform generator generates a low-frequency baseband signal IF based on the received microwave clock signal Ref;

[0053] The low-frequency baseband signal IF is split into two electrical signals by an RF bridge;

[0054] The single-sideband modulation module modulates the fourth single-frequency optical signal OC4 after polarization control with two electrical signals to obtain the optical microwave signal OC5 with carrier suppression.

[0055] The second optical coupler combines the optical microwave signal OC5 and the polarization-controlled third single-frequency optical signal OC3 to obtain the second combined signal OC35. The second combined signal OC35 enters the second photodetector, and the high-frequency coherent wireless signal ET is obtained at the output of the second photodetector.

[0056] For example, the first optical polarization controller and the second optical polarization controller are respectively connected to the output of the multi-channel tunable optical filter of the integrated optical comb repetition frequency signal generation unit, so as to control the polarization state of the third single-frequency optical signal OC3 and the fourth single-frequency optical signal OC4 respectively.

[0057] For example, an arbitrary waveform generator is connected to the output of the radio frequency fractional divider of a standard microwave clock signal generation unit to receive the microwave clock signal Ref, achieve synchronization with the optical comb signal OC, and use the microwave clock signal Ref as an external reference to generate a low-frequency baseband signal IF.

[0058] For example, the RF bridge is a 90° RF bridge, which can split the low-frequency baseband signal IF into a first electrical signal IF1 and a second electrical signal IF2 with a 90° phase difference. The single-sideband modulation module can use the first electrical signal IF1 and the second electrical signal IF2 to perform carrier-suppressed single-sideband modulation on the polarization-controlled fourth single-frequency optical signal OC4, thereby loading the low-frequency baseband signal IF and obtaining the optical microwave signal OC5.

[0059] In this way, the wireless signal generation unit can generate a high-frequency coherent wireless signal ET.

[0060] Based on this, the wireless signal generation device based on integrated optical comb synchronization provided in this embodiment of the invention is designed to meet the high-speed communication and high-positioning accuracy sensing requirements of 6G networks. It can organically combine integrated optical comb technology with wireless communication sensing systems to generate coherent signals based on the wireless communication sensing system with integrated optical comb. It is a low-cost, low-resource-consumption, clock-synchronized wireless signal generation device and method.

[0061] Based on the same technical concept, the present invention also provides a method for generating wireless signals based on integrated optical comb synchronization.

[0062] Figure 2 A flowchart illustrating a wireless signal generation method based on integrated optical comb synchronization according to an embodiment of the present invention is shown.

[0063] like Figure 2 As shown, the wireless signal generation method based on integrated optical comb synchronization in this embodiment may include steps S1 to S3.

[0064] Step S1: Generate optical comb signal OC. Filter the optical comb signal OC to obtain first single-frequency optical signal OC1 and second single-frequency optical signal OC2 with adjacent beams, as well as third single-frequency optical signal OC3 and fourth single-frequency optical signal OC4 with different frequencies. Combine the first single-frequency optical signal OC1 and the second single-frequency optical signal OC2, amplify and beat the signal to obtain a high-frequency clock signal E with the same frequency as the optical comb signal OC.

[0065] This step can be performed by an integrated optical comb repetition rate signal generation unit. Specifically, a pump light can be generated by a distributed feedback laser, and the pump light can be self-injected and locked into a high-quality factor silicon nitride microring to generate an optical comb signal OC. The distributed feedback laser and the high-quality factor silicon nitride microring are integrated on the same optical chip.

[0066] The optical comb signal OC can be input into a multi-channel tunable optical filter for filtering and comb selection. The first single-frequency optical signal OC1 and the second single-frequency optical signal OC2, which are adjacent to each other, are selected and output from the two channels respectively. The other two single-frequency optical signals OC3 and OC4, which have different frequencies, are also selected as optical carriers to provide beat frequency for generating high-frequency wireless signals.

[0067] The first single-frequency optical signal OC1 and the second single-frequency optical signal OC2 are combined by the first optical coupler, then amplified by the first optical amplifier and enter the first photodetector. A high-frequency clock signal E is obtained at the output of the first photodetector.

[0068] Step S2: After amplifying and filtering the high-frequency clock signal, it is then divided by integer and fractional frequencies in sequence to obtain a microwave clock signal with a standard frequency that is synchronized with the high-frequency clock signal.

[0069] This step can be performed by a standard microwave clock signal generation unit. In the standard microwave clock signal generation unit, the RF amplifier amplifies the power of the high-frequency clock signal E. After the amplified high-frequency clock signal E is filtered by an RF filter, it is divided by an RF integer divider to obtain a low-frequency signal E2 with a frequency of 1 / N of the high-frequency clock signal, where N is a positive integer.

[0070] The low-frequency signal E2 is converted to a standard 10MHz or 100MHz microwave clock signal Ref using an RF fractional divider.

[0071] Step S3: Convert the microwave clock signal into a low-frequency baseband signal, and use the low-frequency baseband signal to perform single-sideband modulation on the fourth single-frequency optical signal to generate an optical microwave signal. Combine the optical microwave signal and the third single-frequency optical signal and beat the signal to obtain a high-frequency coherent wireless signal.

[0072] This step can be performed by the wireless signal generation unit. Specifically, in the wireless signal generation unit, the polarization states of the third single-frequency optical signal OC3 and the fourth single-frequency optical signal OC4 can be controlled by the first optical polarization controller and the second optical polarization controller, respectively.

[0073] The third single-frequency optical signal OC3 and the fourth single-frequency optical signal OC4 after polarization control are amplified by the second and third optical amplifiers, respectively.

[0074] The low-frequency baseband signal IF is split into a first electrical signal IF1 and a second electrical signal IF2 with a phase difference of 90° by using an RF bridge.

[0075] By using a single-sideband modulation module, the fourth single-frequency optical signal OC4 after power amplification is subjected to carrier suppression single-sideband modulation based on the first electrical signal IF1 and the second electrical signal IF2, thereby loading the low-frequency baseband signal IF and obtaining the optical microwave signal OC5.

[0076] The second optical coupler combines the optical microwave signal OC5 and the amplified third single-frequency optical signal OC3 to obtain the second combined signal OC35.

[0077] It should be noted that the embodiments of the method section are similar to those of the embodiments of the apparatus section described above, and the technical effects achieved are also similar. For specific details, please refer to the embodiments of the apparatus section described above, which will not be repeated here.

[0078] In summary, the embodiments of the present invention provide a wireless signal generation device and method based on integrated optical comb synchronization, which addresses the high-speed communication and high-positioning accuracy sensing requirements of 6G networks. It can organically combine integrated optical comb technology with wireless communication sensing systems to generate coherent signals based on the wireless communication sensing system with integrated optical comb. It is a low-cost, low-resource-consumption, and clock-synchronized wireless signal generation device and method.

[0079] As can be seen from the above description, the embodiments of the present invention achieve at least the following technical effects:

[0080] (1) The optical comb signal is generated by using an on-chip distributed feedback laser and an on-chip high-quality factor silicon nitride microring, resulting in high light source integration. The principle of self-injection locking to narrow linewidth is utilized to obtain a high-quality microcavity optical comb.

[0081] (2) The scheme of dividing the high-frequency clock signal with the same frequency as the optical comb signal to the standard microwave clock frequency and using it as the synchronization clock of the entire optoelectronic system is proposed. Since the high-frequency clock signal has great potential in achieving ultra-low phase noise performance, using it as the clock signal can improve the overall optoelectronic system parameter level.

[0082] (3) By utilizing the high coherence of the optical comb teeth and the carrier suppression single-sideband modulation of the IQ modulator, the tunability of the output electrical signal is ensured, and various signals (such as single-frequency signals, Chirp signals, QPSK signals, etc.) can be tuned.

[0083] (4) The device link structure is simple and easy to operate, which reduces the complexity of hardware and is easy to miniaturize and integrate.

[0084] It should be noted that similar or identical parts are referred to by the same drawing numbers in the accompanying drawings or description. Implementations not shown or described in the drawings are those known to those skilled in the art. Furthermore, while this document may provide examples of parameters containing specific values, it should be understood that the parameters need not be exactly equal to the corresponding values, but rather approximate the corresponding values ​​within acceptable error tolerances or design constraints.

[0085] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0086] 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.

[0087] The embodiments of the present invention have been described above. However, these embodiments are merely illustrative and not intended to limit the scope of the invention. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of the invention, and all such substitutions and modifications should fall within the scope of the invention.

Claims

1. A wireless signal generation device based on integrated optical comb synchronization, characterized in that, include: An integrated optical comb repetition frequency signal generation unit is used to generate an optical comb signal. The optical comb signal is filtered to obtain a first single-frequency optical signal and a second single-frequency optical signal with adjacent beams, as well as a third single-frequency optical signal and a fourth single-frequency optical signal with different frequencies. The first single-frequency optical signal and the second single-frequency optical signal are combined, amplified, and beat-frequencyd to obtain a high-frequency clock signal with the same frequency as the optical comb signal. A standard microwave clock signal generation unit is used to amplify and filter the high-frequency clock signal, and then sequentially divide it by integer and fractional frequencies to obtain a microwave clock signal with a standard frequency that is synchronized with the high-frequency clock signal. A wireless signal generation unit is used to convert the microwave clock signal into a low-frequency baseband signal, perform single-sideband modulation on the fourth single-frequency optical signal using the low-frequency baseband signal to generate an optical microwave signal, and combine the optical microwave signal and the third single-frequency optical signal through beam combining and beat frequency modulation to obtain a high-frequency coherent wireless signal.

2. The apparatus according to claim 1, characterized in that, The integrated optical comb repetition rate signal generation unit includes a distributed feedback laser, a high-quality factor silicon nitride microring, a multi-channel tunable optical filter, a first optical coupler, a first optical amplifier, and a first photodetector connected in sequence, wherein: The distributed feedback laser generates pump light, which is self-injected and locked into the high-quality factor silicon nitride microring to generate the optical comb signal. The multi-channel tunable optical filter filters and selects the comb teeth of the optical comb signal to obtain a first single-frequency optical signal and a second single-frequency optical signal with adjacent beams, as well as a third single-frequency optical signal and a fourth single-frequency optical signal with different frequencies. The first optical coupler combines the first single-frequency optical signal and the second single-frequency optical signal to obtain a first combined signal. The first combined signal is amplified by the first optical amplifier and then enters the first photodetector to obtain a high-frequency clock signal with the same frequency as the optical comb signal.

3. The apparatus according to claim 2, characterized in that, The distributed feedback laser and the high-quality factor silicon nitride microring are integrated on the same optical chip.

4. The apparatus according to claim 1 or 2, characterized in that, The standard microwave clock signal generation unit includes a radio frequency amplifier, a radio frequency filter, a radio frequency integer divider, and a radio frequency fractional divider connected in sequence, wherein: The radio frequency amplifier amplifies the power of the high-frequency clock signal. After the amplified high-frequency clock signal is filtered by the radio frequency filter, it is divided into integers by the radio frequency integer divider to obtain a low-frequency signal with a frequency of 1 / N of the high-frequency clock signal, where N is a positive integer. The low-frequency signal is converted to a standard frequency microwave clock signal by the radio frequency fractional divider.

5. The apparatus according to claim 1 or 2, characterized in that, The wireless signal generating unit includes: The first optical polarization controller and the second optical polarization controller are used to control the polarization state of the third single-frequency optical signal and the fourth single-frequency optical signal, respectively. The second and third optical amplifiers are used to amplify the power of the third and fourth single-frequency optical signals after polarization control, respectively. An arbitrary waveform generator, an RF bridge, a single-sideband modulation module, a second optical coupler, and a second photodetector are connected in sequence, wherein: The arbitrary waveform generator generates a low-frequency baseband signal based on the received microwave clock signal; The low-frequency baseband signal is split into two electrical signals by the radio frequency bridge. The single-sideband modulation module modulates the power-amplified fourth single-frequency optical signal with carrier suppression using the two electrical signals to obtain an optical microwave signal. The second optical coupler combines the optical microwave signal and the amplified third single-frequency optical signal to obtain a second combined signal. The second combined signal enters the second photodetector for power detection to obtain the wireless signal.

6. The apparatus according to claim 5, characterized in that, The radio frequency bridge is a 90° radio frequency bridge, used to split the low-frequency baseband signal into a first electrical signal and a second electrical signal with a 90° phase difference.

7. The apparatus according to claim 1, characterized in that, The standard frequency is 10MHz or 100MHz.

8. A method for generating wireless signals based on integrated optical comb synchronization, characterized in that, include: An optical comb signal is generated, and the optical comb signal is filtered to obtain a first single-frequency optical signal and a second single-frequency optical signal with adjacent beams, as well as a third single-frequency optical signal and a fourth single-frequency optical signal with different frequencies. The first single-frequency optical signal and the second single-frequency optical signal are combined, amplified, and beat-frequencyd to obtain a high-frequency clock signal with the same frequency as the optical comb signal. After amplification and filtering, the high-frequency clock signal is then divided by integer and fractional frequencies in sequence to obtain a microwave clock signal with a standard frequency that is synchronized with the high-frequency clock signal. The microwave clock signal is converted into a low-frequency baseband signal, and the fourth single-frequency optical signal is modulated by the low-frequency baseband signal to generate an optical microwave signal. The optical microwave signal and the third single-frequency optical signal are combined and beat-frequency-controlled to obtain a high-frequency coherent wireless signal.

9. The method according to claim 8, characterized in that, The generation of the optical comb signal includes: Pump light is generated by a distributed feedback laser and self-injected into a high-quality factor silicon nitride microring to generate the optical comb signal. The distributed feedback laser and the high-quality factor silicon nitride microring are integrated on the same optical chip.

10. The method according to claim 8, characterized in that, The process of using the low-frequency baseband signal to perform single-sideband modulation on the fourth single-frequency optical signal to generate an optical microwave signal, and then combining the optical microwave signal and the third single-frequency optical signal through beam combining and beat frequency modulation to obtain a high-frequency coherent wireless signal, includes: The polarization states of the third and fourth single-frequency optical signals are controlled by the first and second optical polarization controllers, respectively. The third and fourth single-frequency optical signals after polarization control are amplified by the second and third optical amplifiers, respectively. The low-frequency baseband signal is split into two electrical signals using an RF bridge. By using a single-sideband modulation module, the fourth single-frequency optical signal after power amplification is subjected to carrier-suppressed single-sideband modulation based on the two electrical signals to obtain an optical microwave signal. The second optical coupler combines the optical microwave signal and the amplified third single-frequency optical signal to obtain a second combined signal.

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