Integrated microwave photon frequency conversion system

Abstract

The invention provides an integrated microwave photon frequency conversion system, and relates to the technical field of optical communication. The integrated microwave photon frequency conversion system comprises a laser used for outputting optical carriers; the frequency conversion unit is used for splitting the optical carrier into four light beams, loading an input bandwidth signal to two adjacent light beams in the four light beams to realize single side band modulation, and loading an input local oscillator signal to the other two adjacent light beams to realize single side band modulation; and carrying out frequency mixing and filtering processing on the four loaded light beams in an optical domain to obtain an output signal, wherein the bandwidth signal comprises a radio frequency signal or an intermediate frequency signal; and the photoelectric detector is used for performing beat frequency processing on the output signal to obtain a frequency conversion signal.

Description

Technical Field

[0001] The present disclosure relates to the field of optical communication technology, and more specifically, to an integrated microwave photonic frequency conversion system. Background Art

[0002] Frequency conversion units are an indispensable part of many systems such as communications and radars. Since low-frequency signals are easy to generate and process, while high-frequency signals are easy to transmit and transmit, up-conversion technology is needed in the transmitter to first move the generated low-frequency signals to the RF frequency point. Similarly, down-conversion technology is needed in the receiver to move the spatial RF signal to a fixed intermediate frequency point so that it can be digitized more easily.

[0003] In recent years, microwave photonic technology has been widely used in the field of frequency conversion due to its advantages such as wide spectrum coverage, large instantaneous bandwidth, high isolation, and anti-electromagnetic interference. However, the traditional microwave photonic frequency conversion architecture is based on discrete devices, does not have size advantages, and has low mixing spurious suppression. Generally, electronic filters are used after the frequency converter to improve the spectral purity of the output signal, which results in the instantaneous bandwidth of the system being limited by the bandwidth of the electronic filter. In addition, due to the different frequency conversion requirements in the transmitter and receiver, different frequency conversion structures usually need to be designed, which further increases the complexity of the link. Summary of the invention

[0004] In view of this, the present disclosure provides an integrated microwave photonic frequency conversion system.

[0005] The present disclosure provides an integrated microwave photon frequency conversion system, comprising: a laser, used to output an optical carrier; a frequency conversion unit, used to split the optical carrier into four beams, and load an input bandwidth signal onto two adjacent beams of the four beams to achieve single-sideband modulation, and load an input local oscillator signal onto the other two adjacent beams to achieve single-sideband modulation; and perform frequency mixing and filtering on the four loaded beams in an optical domain to obtain an output signal; wherein the bandwidth signal includes a radio frequency signal or an intermediate frequency signal; and a photodetector, used to perform beat frequency processing on the output signal to obtain a frequency conversion signal.

[0006] According to an embodiment of the present disclosure, the frequency conversion unit includes: a beam splitting module, which is used to divide the optical carrier into four light beams; a modulation module includes two parallel first modulators and a second modulator; wherein the first modulator is used to load the bandwidth signal onto two adjacent light beams among the four light beams, and perform phase processing on the two adjacent light beams that have been loaded so that the first modulator is located at a preset working point to achieve single-sideband modulation; the second modulator is used to load the local oscillator signal onto the other two adjacent light beams, and perform phase processing on the other two adjacent light beams that have been loaded so that the second modulator is located at a preset working point to achieve single-sideband modulation; a beam combining module is used to combine the four loaded light beams to output a mixed signal; and a filtering module is used to filter the mixed signal to obtain an output signal.

[0007] According to an embodiment of the present disclosure, the first modulator and the second modulator are both dual-drive modulators, and the dual-drive modulator includes: two waveguides, one end of the two waveguides is used to receive two adjacent light beams or another two adjacent light beams among the four light beams; a metal electrode structure, which is used to receive a bandwidth signal or a local oscillator signal and to change the phase of the two waveguides with the change of the bandwidth signal through an electro-optical effect, and to load the bandwidth signal or the local oscillator signal onto two adjacent light beams or another two adjacent light beams among the four light beams; a metal thermoelectrode, which is located at one end of one of the two waveguides, and is used to change the refractive index of one of the two waveguides by controlling the temperature of the metal thermoelectrode, so as to regulate the phase difference between the two waveguides.

[0008] According to an embodiment of the present disclosure, the beam splitting module includes: a first beam splitter for equally splitting the optical carrier into a first beam and a second beam; a second beam splitter for equally splitting the first beam into a third beam and a fourth beam; and a third beam splitter for equally splitting the second beam into a fifth beam and a sixth beam.

[0009] According to an embodiment of the present disclosure, the beam combining module includes: a fourth beam splitter, used to combine the third to fourth light beams that have been loaded into a seventh light beam; a fifth beam splitter, used to combine the fifth to sixth light beams that have been loaded into an eighth light beam; and a sixth beam splitter, used to combine the seventh light beam and the eighth light beam into a mixed signal, and transmit the mixed signal to the filtering module.

[0010] According to an embodiment of the present disclosure, a filtering module includes: a microring resonant cavity, including a multi-mode straight waveguide and a ring waveguide, for receiving a mixing signal to generate a periodic resonance peak; a metal thermoelectrode, arranged on the ring waveguide, for regulating the temperature of the ring waveguide to change the refractive index of the ring waveguide, so as to regulate the resonant wavelength of the resonance peak to achieve filtering of the optical carrier.

[0011] According to an embodiment of the present disclosure, the waveguides in the frequency conversion unit are all ridge waveguides.

[0012] According to an embodiment of the present disclosure, the metal electrode is a traveling wave electrode.

[0013] According to an embodiment of the present disclosure, the material of the metal thermode includes a nickel-chromium alloy.

[0014] According to an embodiment of the present disclosure, the first to sixth optical splitters are all 1×2 multi-mode interferometers.

[0015] According to the embodiments of the present disclosure, the frequency conversion unit is provided to implement single-sideband modulation of the bandwidth signal and the local oscillator signal, and improve the frequency conversion gain and spurious suppression ratio, while avoiding periodic power attenuation.

[0016] According to the embodiments of the present disclosure, a monolithically integrated frequency conversion unit is provided to reduce the volume and complexity of the system, and optical domain filtering is used to solve the problem of limited instantaneous bandwidth of traditional frequency conversion systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0018] Figure 1 The structure diagram of the integrated microwave photon frequency conversion system according to the embodiment of the present disclosure is schematically shown;

[0019] Figure 2 Schematically shows a structural diagram of a dual-drive modulator according to an embodiment of the present disclosure;

[0020] Figure 3 A schematic cross-sectional view of a modulation arm of a dual-drive modulator according to an embodiment of the present disclosure is schematically shown;

[0021] Figure 4 schematically shows a normalized transmission curve of a dual-drive modulator according to an embodiment of the present disclosure;

[0022] Figure 5 A schematic diagram of a down-converted beat frequency spectrum according to an embodiment of the present disclosure is shown schematically;

[0023] Figure 6 A schematic diagram of an up-converted beat frequency spectrum according to an embodiment of the present disclosure is shown;

[0024] Description of reference numerals:

[0025] 1. Laser; 2. Frequency conversion unit; 3. Beam splitting module; 3-1. First spectrometer; 3-2. Second spectrometer; 3-3. Third spectrometer; 4. Modulation module; 4-1. Metal thermode; 4-2. Thermally tunable waveguide; 4-3. Parallel waveguide; 4-4. First metal electrode; 4-5. Second metal electrode; 4-6. First metal electrode; 4-7. Waveguide; 4-8. Substrate; 5. Beam combining module; 5-1. Fifth spectrometer; 5-2. Fourth spectrometer; 5-3. Sixth spectrometer; 6. Filtering module; 6-1. Metal thermode; 7. Photodetector. DETAILED DESCRIPTION

[0026] Hereinafter, embodiments of the present disclosure 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 present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known systems and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0027] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0028] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0029] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0030] Figure 1 The structure diagram of the integrated microwave photonic frequency conversion system of the embodiment of the present disclosure is schematically shown.

[0031] like Figure 1As shown, the present disclosure provides an integrated microwave photon frequency conversion system, including: a laser 1, used to output an optical carrier; a frequency conversion unit 2, used to split the optical carrier into four beams, and load the input bandwidth signal RF / IF onto two adjacent beams of the four beams to achieve single sideband modulation, and load the input local oscillator signal LO onto the other two adjacent beams to achieve single sideband modulation; and mix and filter the four loaded beams in the optical domain to obtain an output signal; wherein the bandwidth signal includes a radio frequency signal RF or an intermediate frequency signal IF; and a photodetector 7, used to perform beat frequency processing on the output signal to obtain a frequency conversion signal.

[0032] In the embodiment of the present disclosure, the mixing spurious suppression ratio is an important performance index of the microwave photon mixer. The mixing spurious refers to the frequency component that is not desired to appear at the output end of the microwave photon mixer. When the frequency is ω RF The RF signal and frequency are ω LO When the LO signal is added to the mixer, the generated frequency component can be expressed as (nω RF ±mω LO ), divided into three categories: 1) the desired frequency conversion signal when n=1 and m=1; 2) LO and RF leakage when n=1, m=0 or n=0, m=1; 3) harmonic spurs when n and m take other values. Only the frequency oscillation between the +1st order RF and +1st order (or -1st order) LO sidebands can produce the desired frequency conversion components, so it is necessary to eliminate the unwanted mixing spurs, namely LO, RF leakage and harmonic spurs.

[0033] The present invention realizes single-sideband modulation of bandwidth signal and local oscillator signal by designing a frequency conversion unit, and filters out carrier components not needed by the beat frequency through cascaded microring resonators, effectively eliminating unnecessary mixing spurious signals, improving the spurious suppression ratio, while ensuring the frequency conversion gain and avoiding periodic power attenuation.

[0034] According to an embodiment of the present disclosure, the frequency conversion unit 2 includes: a beam splitting module 3, which is used to divide the optical carrier into four light beams; a modulation module 4 includes two parallel first modulators and a second modulator; wherein the first modulator is used to load the bandwidth signal onto two adjacent light beams among the four light beams, and phase-process the two adjacent light beams that have been loaded so that the first modulator is located at a preset working point to achieve single-sideband modulation; the second modulator is used to load the local oscillator signal onto the other two adjacent light beams, and phase-process the other two adjacent light beams that have been loaded so that the second modulator is located at a preset working point to achieve single-sideband modulation; a beam combining module 5, which is used to combine the four loaded light beams to output a mixed signal; and a filtering module 6, which is used to filter the mixed signal to obtain an output signal.

[0035] In the embodiment of the present disclosure, a monolithic integrated frequency conversion unit is provided, which avoids the use of electronic filters, significantly reduces the volume and complexity of the system, and at the same time, optical domain filtering solves the problem of limited instantaneous bandwidth of traditional frequency conversion systems. At the same time, by adjusting the preset working points of the two modulators, flexible switching of up and down frequency conversion is achieved, which has broad application prospects in optical carrier communication systems.

[0036] Figure 2 The structure of a dual-drive modulator according to an embodiment of the present disclosure is schematically shown.

[0037] Figure 3 The cross-sectional view of a modulation arm of a dual-drive modulator according to an embodiment of the present disclosure is schematically shown.

[0038] like Figure 2 and Figure 3 As shown, according to an embodiment of the present disclosure, the first modulator and the second modulator are both dual-drive modulators, and the dual-drive modulator includes: two waveguides, one end of the two waveguides is used to receive two adjacent light beams or another two adjacent light beams among the four light beams; a metal electrode structure, which is used to receive a bandwidth signal or a local oscillator signal and to change the phase of the two waveguides with the change of the bandwidth signal through an electro-optical effect, and to load the bandwidth signal or the local oscillator signal carried by the electrical signal onto two adjacent light beams or another two adjacent light beams among the four light beams; a metal thermoelectrode, which is located at one end of one of the two waveguides, and is used to change the refractive index of one waveguide by controlling the temperature of the metal thermoelectrode, so as to regulate the phase difference between the two waveguides.

[0039] In the embodiment of the present disclosure, both waveguides include two parallel waveguides 4-3 and two thermally tunable waveguides 4-2. The refractive index of the thermally tunable waveguide 4-2 is changed with the change of temperature by regulating the metal thermoelectrode 4-1, thereby regulating the phase difference of the light beams passing through the two waveguides. The metal electrode structure includes a first metal electrode 4-4 located between the two waveguides; two second metal electrodes 4-5 located outside the two waveguides for receiving bandwidth signals or local oscillator signals; and two first metal electrodes 4-6 located on the other side of the two second metal electrodes 4-5. By applying a voltage to the metal electrode structure, the refractive indices of the two waveguides change due to the electro-optical effect, thereby causing the accumulated phase of the two light beams to change with the change of the refractive index of the waveguides, and the refractive indices of the two waveguides can be regulated separately. Among them, the metal electrode structure and the parallel waveguides constitute the modulation arm of the dual-drive modulator.

[0040] According to an embodiment of the present disclosure, the beam splitting module 3 includes: a first beam splitter 3-1, used to split the optical carrier into a first beam and a second beam; a second beam splitter 3-2, used to split the first beam into a third beam and a fourth beam; a third beam splitter 3-3, used to split the second beam into a fifth beam and a sixth beam.

[0041] According to an embodiment of the present disclosure, the beam combining module 5 includes: a fourth beam splitter 5-2, used to combine the third to fourth light beams that have been loaded and processed into a seventh light beam; a fifth beam splitter 5-1, used to combine the fifth to sixth light beams that have been loaded and processed into an eighth light beam; a sixth beam splitter 5-3, used to combine the seventh light beam and the eighth light beam into a mixed signal, and transmit the mixed signal to the filtering module.

[0042] In the embodiment of the present disclosure, the beam combining module combines the four light beams that have been loaded into the system in pairs to achieve the transformation of phase information into intensity information, and then performs beam combining processing to output a mixed signal.

[0043] According to an embodiment of the present disclosure, the beam combining module also includes a metal thermode. By adjusting the external voltage of the metal thermode, the phase difference between the two light beams of the beam combining module is controlled to be zero, so that the seventh light beam and the eighth light beam interfere constructively.

[0044] According to an embodiment of the present disclosure, the filtering module 6 includes: a microring resonant cavity, which includes a multi-mode straight waveguide and a ring waveguide, and is used to receive a mixing signal to generate a periodic resonance peak; a metal thermoelectrode 6-1, which is arranged on the ring waveguide and is used to regulate the temperature of the ring waveguide to change the refractive index of the ring waveguide, so as to regulate the resonant wavelength of the resonance peak to achieve filtering of the optical carrier.

[0045] In the embodiments of the present disclosure, a multimode straight waveguide is used to weaken the overlap between the light field and the side wall in the waveguide, thereby reducing the transmission loss; the Euler bent ring waveguide is used to suppress the excitation of high-order modes, and the all-pass microring resonant cavity can produce a series of periodic resonance peaks. The light beam at the resonance wavelength will be significantly suppressed and cannot be output from the output end of the microring resonant cavity; in the embodiments of the present disclosure, the optical carrier is filtered out by the microring resonant cavity to ensure the frequency conversion gain and spurious suppression ratio, avoid the use of subsequent electronic filters, and solve the problem of limited instantaneous bandwidth of traditional frequency conversion systems.

[0046] According to an embodiment of the present disclosure, the waveguides in the frequency conversion unit are all ridge waveguides.

[0047] According to an embodiment of the present disclosure, the metal electrode is a traveling wave electrode.

[0048] According to an embodiment of the present disclosure, the material of the metal thermode includes a nickel-chromium alloy.

[0049] According to an embodiment of the present disclosure, the first to sixth optical splitters are all 1×2 multi-mode interferometers.

[0050] According to an embodiment of the present disclosure, the output wavelength of the laser is an optical carrier of 1550 nm.

[0051] Figure 4 The normalized transmission curve of the dual-drive modulator according to an embodiment of the present disclosure is schematically shown.

[0052] Figure 5 A schematic diagram of a down-converted beat frequency spectrum according to an embodiment of the present disclosure is shown schematically.

[0053] like Figure 4 and Figure 5 As shown, in a possible embodiment of the present disclosure, the present disclosure provides a working process of down-conversion:

[0054] Step 1: The RF signal and the local oscillator signal are respectively input into the metal electrodes 4-5 of two parallel dual-drive modulators after passing through a 90° bridge.

[0055] Step 2: When the RF signal and the local oscillator signal are transmitted in the metal electrode structure, the refractive index of the two arms of the dual-drive modulator changes under the action of the electric field. When the two beams of light are transmitted through the two-arm waveguide, corresponding phase changes will occur, that is, the phase accumulation of the two beams of light changes with the intensity of the RF signal and the local oscillator signal. This process successfully loads the RF signal and the local oscillator signal onto the third to fourth light beams and the fifth to sixth light beams, respectively.

[0056] Step 3: Apply voltage to the metal thermode 4-1 to make the metal thermode heat up, change the temperature of the waveguide 4-2 around the metal thermode 4-1, and then change the refractive index of the waveguide. When the light beam passes through the thermal tuning waveguide 4-2, a phase accumulation related to the external applied voltage will be generated. By controlling the applied voltage, the phase difference introduced by the thermal tuning waveguides of the two arms of the two parallel dual-drive modulators is +π / 2. According to the normalized transmission response curve of the modulator, the dual-drive modulator works at the orthogonal bias point at this time, such as Figure 4 As shown, the abscissa is the phase difference between the two waveguides, and the ordinate is the transmittance.

[0057] Step 4: The modulated third to fourth light beams and the fifth to sixth light beams are combined into the seventh and eighth light beams after passing through the fourth beam splitter 5-2 and the fifth beam splitter 5-1, and the phase information is converted into intensity information. According to the modulation principle of the modulator, at this time, the two parallel dual-drive modulators both realize single-sideband modulation, and the -1 order sideband is suppressed.

[0058] Step 5: Adjust the external voltage on the metal hot electrode on the beam combining module so that the two modulators operate at the maximum transmission point. The seventh and eighth light beams are combined into a mixed light beam after passing through the sixth beam splitter 5-3, wherein the spectral components of the mixed light beam mainly include the carrier frequency, the +1-order RF signal frequency and the +1-order local oscillator signal frequency.

[0059] Step six: The mixed light beam is then transmitted to the filter module 6, which is composed of an all-pass micro-ring resonant cavity and a metal thermoelectrode 6-1, wherein the all-pass micro-ring resonant cavity is composed of a multi-mode straight waveguide and an Euler bent ring waveguide. The multi-mode straight waveguide is used to weaken the overlap between the light field and the side wall in the waveguide, thereby reducing the transmission loss; the Euler bent ring waveguide is used to suppress the excitation of high-order modes. The all-pass micro-ring resonant cavity can generate a series of periodic resonance peaks, and the light at the resonance wavelength will be significantly suppressed and cannot be output from the output end of the micro-ring resonant cavity.

[0060] Step seven: by applying voltage to the metal thermode 6-1 of the all-pass microring resonant cavity to make the metal thermode 6-1 heat up, changing the temperature of the waveguide around the metal thermode 6-1, and then changing the refractive index of the waveguide, the resonant wavelength of the all-pass microring resonant cavity can be drifted. By precisely controlling the magnitude of the applied voltage, the resonant wavelength is shifted to the wavelength of the optical carrier, and the optical carrier in the mixing light beam can be filtered out to obtain an output signal. At this time, the main spectral components of the output signal are the +1-order RF signal frequency and the +1-order local oscillator signal frequency.

[0061] Step 8: The output signal is transmitted to the photodetector 7 to obtain an intermediate frequency signal generated by the beat frequency of the +1-order RF signal and the +1-order local oscillator signal, whose frequency is equal to the difference between the RF signal frequency and the local oscillator signal frequency, thereby realizing down-conversion. Figure 6 The schematic diagram of the up-conversion beat frequency spectrum according to the embodiment of the present disclosure is shown schematically.

[0062] like Figure 4 , 6 As shown, in a possible embodiment of the present disclosure, the present disclosure provides a working process of up-conversion:

[0063] Step 1: The intermediate frequency signal and the local oscillator signal are respectively input into the metal electrodes 4-5 of two parallel dual-drive modulators after passing through a 90° bridge.

[0064] Step 2: Load the intermediate frequency signal and the local oscillator signal onto the third to fourth light beams and the fifth to sixth light beams, wherein the loading process is consistent with the loading principle in the above-mentioned down-conversion and will not be repeated here.

[0065] Step 3: Apply voltage to the metal thermode 4-1 to make it heat up, change the temperature of the waveguide around the metal thermode 4-1, and then change the refractive index of the waveguide. When the light beam passes through the thermal tuning waveguide 4-2, a phase accumulation related to the external applied voltage will be generated. By controlling the external voltage, the phase difference introduced by the thermal tuning waveguides of the two arms of the first modulator is -π / 2, and the phase difference introduced by the thermal tuning waveguides of the two arms of the second dual-drive modulator is +π / 2. According to the normalized transmission response curve of the modulator, the dual-drive modulator operates at the orthogonal bias point at this time, such as Figure 4 shown.

[0066] Step 4: The modulated third to fourth light beams and the fifth to sixth light beams are combined into the seventh and eighth light beams after passing through the fourth beam splitter 5-2 and the fifth beam splitter 5-1, respectively, and the phase information is converted into intensity information. According to the modulation principle of the modulator, at this time, both the upper and lower dual-drive modulators realize single-sideband modulation, wherein the +1-order sideband of the upper branch dual-drive modulator is suppressed, and the -1-order sideband of the lower branch dual-drive modulator is suppressed.

[0067] Step 5: Adjust the external voltage on the metal hot electrode on the beam combining module so that the two modulators operate at the maximum transmission point. The seventh and eighth light beams are combined into a mixed light beam after passing through the sixth beam splitter 5-3, wherein the spectral components of the mixed light beam mainly include the carrier frequency, the -1 order intermediate frequency signal frequency and the +1 order local oscillator signal frequency.

[0068] Step six: The mixed light beam is then transmitted to the filtering module 6. By precisely controlling the voltage applied to the metal thermoelectrode 6-1, the resonant wavelength of the all-pass microring resonator is shifted to the wavelength of the optical carrier, thereby filtering out the optical carrier in the mixed light beam and obtaining an output signal. At this time, the main spectral components of the output signal are the -1-order intermediate frequency signal frequency and the +1-order local oscillator signal frequency.

[0069] Step 7: The output signal is transmitted to the photodetector 7 to obtain a radio frequency signal generated by the beat frequency of the -1 order intermediate frequency signal and the +1 order local oscillator signal, whose frequency is equal to the sum of the intermediate frequency signal frequency and the local oscillator signal frequency, thereby realizing up-conversion.

[0070] exist Figure 5 , 6 In the beat frequency spectrum shown, ω RF is the frequency of the RF signal, ω LO is the frequency of the LO signal, ω cThe integrated reconfigurable microwave photonic frequency conversion system provided by the disclosed embodiment realizes single-sideband modulation of bandwidth signal and local oscillator signal by using a mixing unit with dual parallel dual-drive modulator as the core. At the same time, by changing the thermal adjustment voltage to adjust the bias point of the dual parallel dual-drive modulator, flexible switching of up and down frequency conversion can be realized. The proposed integrated reconfigurable microwave photonic frequency conversion system has broad application prospects in optical wireless communication systems.

[0071] It will be appreciated by those skilled in the art that the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways, even if such combinations and / or combinations are not explicitly described in the present disclosure. In particular, the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways without departing from the spirit and teachings of the present disclosure. All of these combinations and / or combinations fall within the scope of the present disclosure.

[0072] The embodiments of the present disclosure are described above. However, these embodiments are only for illustrative purposes and are not intended to limit the scope of the present disclosure. Although the embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. The scope of the present disclosure is defined by the attached claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. An integrated microwave photon frequency conversion system, characterized in that: include: A laser for outputting an optical carrier; A frequency conversion unit, used for splitting the optical carrier into four beams, loading the input bandwidth signal onto two adjacent beams of the four beams to achieve single sideband modulation, and loading the input local oscillator signal onto the other two adjacent beams to achieve single sideband modulation; and mixing and filtering the four beams after loading in the optical domain to obtain output signals; wherein the bandwidth signal includes a radio frequency signal or an intermediate frequency signal; as well as The photoelectric detector is used to perform beat frequency processing on the output signal to obtain a frequency conversion signal.

2. The integrated microwave photon frequency conversion system according to claim 1, characterized in that: The frequency conversion unit comprises: A beam splitting module, used for equally dividing the optical carrier into the four beams; The modulation module includes two parallel first modulators and a second modulator; The first modulator is used to load the bandwidth signal onto two adjacent light beams among the four light beams, and perform phase processing on the two adjacent light beams that have been loaded so that the first modulator is located at a preset working point to achieve single sideband modulation; The second modulator is used to load the local oscillator signal onto the other two adjacent light beams, and perform phase processing on the other two adjacent light beams after the loading process so that the second modulator is located at a preset working point to realize single sideband modulation; A beam combining module, used for combining the four light beams that have been loaded and processed to output a mixed signal; The filtering module is used to filter the mixed signal to obtain the output signal.

3. The integrated microwave photon frequency conversion system according to claim 2, characterized in that: The first modulator and the second modulator are both dual-drive modulators, and the dual-drive modulator includes: two waveguides, one end of each of the two waveguides being used for receiving the two adjacent light beams or the other two adjacent light beams among the four light beams; A metal electrode structure, used for receiving the bandwidth signal or the local oscillator signal and changing the phases of the two waveguides with the bandwidth signal through an electro-optical effect, and loading the bandwidth signal or the local oscillator signal onto two adjacent beams or other two adjacent beams among the four light beams; The metal thermode is located at one end of one of the two waveguides and is used to change the refractive index of the one waveguide by controlling the temperature of the metal thermode so as to adjust the phase difference between the two waveguides.

4. The integrated microwave photon frequency conversion system according to claim 2, characterized in that: The beam splitting module comprises: A first optical splitter, used for equally splitting the optical carrier into a first light beam and a second light beam; A second beam splitter, used to equally split the first light beam into a third light beam and a fourth light beam; The third beam splitter is used to equally split the second beam into a fifth beam and a sixth beam.

5. The integrated microwave photon frequency conversion system according to claim 4, characterized in that: The beam combining module comprises: a fourth beam splitter, used for combining the third to fourth light beams that have been loaded into a seventh light beam; a fifth beam splitter, used for combining the fifth to sixth light beams that have been loaded into an eighth light beam; The sixth beam splitter is used to combine the seventh light beam and the eighth light beam into the mixed signal, and transmit the mixed signal to the filtering module.

6. The integrated microwave photon frequency conversion system according to claim 3, characterized in that: The filtering module comprises: A micro-ring resonant cavity, comprising a multi-mode straight waveguide and a ring waveguide, for receiving the mixing signal to generate a periodic resonance peak; The metal thermode is arranged on the annular waveguide and is used to adjust the temperature of the annular waveguide to change the refractive index of the annular waveguide, so as to adjust the resonant wavelength of the resonance peak to filter out the optical carrier.

7. The integrated microwave photon frequency conversion system according to claim 6, characterized in that: The waveguides in the frequency conversion unit are all ridge waveguides.

8. The integrated microwave photon frequency conversion system according to claim 3, characterized in that: The metal electrode is a traveling wave electrode.

9. The integrated microwave photon frequency conversion system according to claim 3, characterized in that: The material of the metal hot electrode includes nickel-chromium alloy.

10. The integrated microwave photon frequency conversion system according to claim 5, characterized in that: The first to sixth optical splitters are all 1×2 multi-mode interferometers.

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