DP-MZM-based reconfigurable mixer with phase shift and image rejection functions

Abstract

The invention discloses a DP-MZM-based reconfigurable mixer with phase shift and image rejection functions, and belongs to the field of microwave photon signal processing. By adjusting an input radio frequency signal and a direct current bias voltage of the DP-MZM1, four different LO frequency doubling and mixing functions can be realized. By controlling the angle alpha between the polarization direction of the polarization analyzer and one axis of the modulator, the phase of the generated signal can be flexibly tuned in the range of 0-360 degrees. When combined with the optical frequency comb, the multi-channel multi-band frequency conversion system can be expanded into a multi-channel multi-band frequency conversion system with independent phase tuning capability by utilizing the channel switching and frequency slot selection functions of the wavelength selection switch, and parallel output of various frequency mixing results can be realized. By adjusting the phase difference between the two-channel output signals, I / Q mixing, double-balanced mixing and image rejection mixing can be configured. The scheme is not influenced by direct current bias drift, the system complexity is reduced, and the frequency conversion efficiency is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of microwave photon signal processing, and particularly relates to a reconfigurable mixer with phase shift and image rejection function based on a DP-MZM. BACKGROUND

[0002] As an inevitable trend of mobile communication, space-based Internet of Things is expected to play an important role in building information networks across space, air, land and sea. Compared with traditional satellites, multi-beam high-throughput satellites have higher transmission bandwidth and stronger on-board processing capability, making them a key component of future space-based Internet of Things. However, with the rapid development of K-band and above and millimeter wave high-temperature superconducting technology, the method of electric domain processing is increasingly unable to meet the multi-band frequency conversion needs of satellite payloads. In recent years, research has focused on microwave signal processing based on photonics. Compared with traditional on-board electric domain processing technology, the mixer based on microwave photon technology has the advantages of large bandwidth, low insertion loss, high integration and anti-electromagnetic interference.

[0003] The mixing function is a basic feature of the satellite payload electronic receiving and transmitting system. The mixer can convert signals of different frequency bands to meet the needs of on-board multi-band signal processing. With the development of microwave photon technology, researchers have proposed a variety of microwave photon mixing schemes. The paper "A Filterless Reconfigurable Frequency Mixer Based on a Wideband Photonic Microwave Phase Shifter" proposes a reconfigurable mixer based on a single polarization division multiplexing double parallel Mach-Zehnder modulator (PDM-DP-MZM). This scheme generates a carrier-suppressed single sideband (CS-SSB) signal without using a filter. The paper "Dual-Output Microwave Photonic Frequency Up- and Down-Converter Using a 90◦ Optical Hybrid Without Filtering" designs a dual-output microwave photon frequency converter using a 90° optical hybrid coupler. The paper "Photonic Downconversion of RF Signals with Improved Conversion Efficiency and SFDR" demonstrates a microwave photon downconverter based on a double parallel Mach-Zehnder modulator (DP-MZM) and a digital signal post-processing algorithm. The above schemes only use the first-order local oscillator (LO) harmonic sideband for mixing. However, in order to obtain frequency conversion signals of different frequency bands, multiple local oscillator signals of different frequencies are needed, which inevitably leads to an increase in system complexity, a decrease in flexibility and an increase in cost.

[0004] The control of signal phase is a prerequisite for achieving image rejection and is crucial in microwave photonic signal processing. Therefore, the ability to have 360° full-range phase shift tuning is one of the core functions in various signal processing applications. However, some current mixing schemes can only convert frequencies and cannot perform phase shifts, so microwave photonic mixers with phase shift functions have become a research hotspot. The paper "Microwave Photonic I / Q Mixer with Phase Shifting Ability" achieves the phase shift function of the mixer by controlling the bias voltage of the modulator, but this method is easily affected by DC bias drift. The paper "Broadband Photonic Microwave Signal Processor with Frequency Up / Down Conversion and Phase Shifting Capability" achieves the phase shift function by adding a phase modulator (PM) after the PDM-DP-MZM. However, when extended to a multi-channel independent phase tuning system, a PM needs to be added to each channel, which increases the complexity and cost of the system.

[0005] In addition, due to the complexity of the space electromagnetic environment, the satellite antenna receives signals containing image (IM) frequency signals corresponding to the radio frequency (RF) signals. If the mixer does not have image rejection capability, the IM signal will also produce an intermediate frequency (IF) signal of the same frequency after passing through the mixing system. This intermediate frequency signal will overlap with the desired intermediate frequency signal produced by the radio frequency signal, cannot be filtered out, and causes serious interference to subsequent processing, so an image rejection mixer (IRM) is needed to achieve image rejection mixing. However, in the traditional scheme, the manufacturing process of the 90° electrical hybrid coupler introduces an inherent phase deviation, resulting in poor image rejection performance and low image rejection ratio (IRR). SUMMARY

[0006] In view of the deficiencies of the prior art, the present application provides a reconfigurable mixer with phase shift and image rejection functions based on a DP-MZM, which realizes four different LO frequency multiplication mixing functions, and simultaneously realizes I / Q mixing, double-balanced mixing and image rejection mixing through reconfiguration.

[0007] The technical scheme of the present application is:

[0008] The reconfigurable mixer with phase shift and image rejection functions based on a DP-MZM comprises an LO harmonic mixing module and N synchronous phase shift and image rejection modules.

[0009] The LO harmonic mixing module is used to load the radio frequency signal and the local oscillator signal that need to be frequency-converted. Through modulation, the +1st order sideband of the radio frequency signal and the local oscillator signal sideband that meet the frequency conversion requirements are obtained. The +1st order sideband of the radio frequency signal and the local oscillator signal sideband that meet the frequency conversion requirements are combined to obtain orthogonally linearly polarized light of different wavelengths and are respectively input to different synchronous phase shift and image suppression modules.

[0010] The N synchronous phase shift and image suppression modules represent N independently operating channels with the same function. Each synchronous phase shift and image suppression module is used to introduce a specific phase shift into one orthogonally linearly polarized light input and convert it into an electrical signal output, while suppressing the image signal to obtain the final mixed signal.

[0011] Furthermore, the LO harmonic mixing module includes a semiconductor laser, a first polarization controller, a 1×2 optical coupler, a 90° polarization rotator, a first dual parallel Mach-Zehnder modulator in the Y branch, a second dual parallel Mach-Zehnder modulator in the X branch, a wavelength selection switch, a first erbium-doped fiber amplifier, a second erbium-doped fiber amplifier, a 1×N optical coupler, and a polarization combiner.

[0012] The semiconductor laser generates linearly polarized light waves. A first polarization controller adjusts the polarization direction and form of the linearly polarized light waves, outputting a linearly polarized light signal. A 1×2 optical coupler splits the linearly polarized light signal into two equal-power signals. A 90° polarization rotator then adjusts one of the light signals, ultimately obtaining a Y-polarized light signal and an X-polarized light signal. The Y-polarized light signal is modulated by an externally input local oscillator signal into the first dual-parallel Mach-Zehnder modulator in the Y branch, generating the various order sidebands of the local oscillator signal in optical signal form. The X-polarized light signal is input together with the externally input radio frequency signal into the X branch. The second dual-parallel Mach-Zehnder modulator of the branch is used for modulation to obtain the +1st order sideband of the radio frequency signal in the form of an optical signal. The obtained +1st order sideband of the radio frequency signal is amplified by the first erbium-doped fiber amplifier, and then split into N radio frequency signal +1st order sidebands by a 1×N optical coupler with equal power. The wavelength selection switch is used to select each order sideband of the local oscillator signal and output to the second erbium-doped fiber amplifier for amplification. Finally, a polarization combiner is used to combine one of the radio frequency signal +1st order sidebands with the amplified local oscillator signal sideband into the same optical path to generate a path of orthogonally linearly polarized light with different wavelengths and transmit it to a synchronous phase shift and image suppression module. Furthermore, by changing the bias voltage of the first dual-parallel Mach-Zehnder modulator in the Y branch, the ±1st, ±2nd, ±3rd, or ±4th order local oscillator signal sidebands can be selectively retained, or the first dual-parallel Mach-Zehnder modulator in the Y branch can be used to generate 5-line and 7-line flat optical frequency combs respectively. At the same time, by adjusting the bias voltage and the amplitude of the radio frequency signal of the second dual-parallel Mach-Zehnder modulator in the X branch, the second dual-parallel Mach-Zehnder modulator in the X branch can be made to operate in the suppressed carrier single-sideband modulation mode, retaining only the +1st order radio frequency signal sideband.

[0013] Furthermore, the synchronous phase shift and mirror suppression module includes a synchronous phase shift module and a mirror suppression module;

[0014] The synchronous phase shift module is used to introduce a specific phase shift into one orthogonally linearly polarized light input and convert it into an electrical signal output, so as to achieve phase tuning of the output signal in the full range of 0~360°;

[0015] The image suppression module is used to suppress existing image signals.

[0016] Furthermore, the synchronous phase shift module includes a second polarization controller, a 50:50 polarization holding coupler, a first polarization analyzer, a second polarization analyzer, a first photodetector, and a second photodetector;

[0017] The second polarization controller converts one orthogonally linearly polarized light beam into one orthogonally circularly polarized light beam, then splits it into two equal optical signals via a 50:50 polarization-holding coupler. These signals are then input to the first and second analyzers for beat frequency analysis. The first and second analyzers adjust their respective polarization directions... and polarization direction The system generates two frequency conversion signals with phase tuning across the entire range of 0~360°. Then, the first and second photodetectors convert the two frequency conversion signals from optical signals into electrical signals and input them into the image suppression module.

[0018] Furthermore, when the polarization direction between the first analyzer and the second analyzer... and polarization direction When the phase difference is 90° or 45°, the double-balanced mixing or I / Q mixing function is realized respectively.

[0019] Furthermore, the image suppression module employs a 90° electrical hybrid coupler, which introduces a 90° phase shift into one of the two input electrical signals, and then couples it with the other electrical signal to obtain the final mixed signal.

[0020] Furthermore, a 90° electric hybrid coupler is used in the I / Q mixing function to achieve image rejection in downconversion mode.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] This invention enables four different LO harmonic mixing functions, and can also be reconfigured to achieve I / Q mixing, double-balanced mixing, and image suppression mixing. Compared with other microwave photonic mixing schemes, this scheme has certain advantages in bandwidth coverage, spurious suppression, and image suppression capabilities. The reconfigurable LO harmonic mixer can flexibly select appropriate LO harmonic sidebands to participate in the frequency conversion, thereby effectively reducing the requirement for LO signal frequency. ±1, ±2, ±3, or ±4 order LO harmonic sidebands or optical frequency combs (OFCs) can be generated respectively. By appropriately configuring the DP-MZM1 of the Y branch, 5-line and 7-line frequency combs can be generated respectively. Using a wavelength selective switch (WSS), this scheme can be extended into a multi-channel, multi-band frequency conversion system with independent phase tuning capabilities, achieving parallel output of various mixing results. Furthermore, since this invention generates multiple phase-shift signals by increasing the number of analyzers (Pol) rather than modulators, no additional modulators are required, and it is not affected by modulator DC bias drift, thereby effectively reducing system complexity and improving frequency conversion efficiency. By using a polarization controller to control the polarization state and adjusting the angle of the analyzer to achieve phase tuning across the entire 0~360° range, the inherent phase deviation of the 90° hybrid coupler can be compensated for, resulting in better image suppression performance. It offers advantages in bandwidth coverage, spurious emission suppression, and image suppression capabilities. Attached Figure Description

[0023] Figure 1 This is a structural diagram of a reconfigurable mixer with phase shifting and image suppression functions based on DP-MZM in an embodiment of the present invention;

[0024] Among them, 1-semiconductor laser, 2-first polarization controller, 3-1×2 optical coupler, 4-90° polarization rotator, 5-first dual parallel Mach-Zehnder modulator of Y branch, 6-second dual parallel Mach-Zehnder modulator of X branch, 7-wavelength selection switch, 8-first erbium-doped fiber amplifier, 9-second erbium-doped fiber amplifier, 10-1×N optical coupler, 11-polarization combiner, 12-second polarization controller, 13-50:50 polarization holding coupler, 14-first analyzer, 15-second analyzer, 16-first photodetector, 17-second photodetector, 18-90° electrical hybrid coupler;

[0025] Figure 2 This is a schematic diagram of the electrical spectrum of the PD output terminal under different local oscillator conditions in the implementation of this invention;

[0026] Among them, (a) is the signal of the 3rd local oscillator harmonic down-converted at a frequency of 13 GHz; (b) is the signal of the 4th local oscillator harmonic down-converted at a frequency of 8 GHz; (c) is the signal of the 3rd local oscillator harmonic up-converted at a frequency of 43 GHz; and (d) is the signal of the 4th local oscillator harmonic up-converted at a frequency of 48 GHz.

[0027] Figure 3 This is a schematic diagram of the waveform of the signal after phase continuous tuning under the local oscillator frequency doubling and mixing operation in the implementation of the present invention;

[0028] Wherein, (a) is the up-conversion signal; (b) is the down-conversion signal;

[0029] Figure 4 This is a schematic diagram showing the measurement spectrum and waveform of the downconversion intermediate frequency and the mirror intermediate frequency signals under the image suppression function in this embodiment of the invention;

[0030] Among them, (a) is the spectrum of the intermediate frequency signal; and (b) is the waveform of the intermediate frequency signal. Detailed Implementation

[0031] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0032] This reconfigurable mixer based on the DP-MZM features phase shifting and image suppression capabilities. It can perform four different LO frequency multiplication mixing functions and, through reconfiguration, achieve I / Q mixing, double-balanced mixing, and image suppression mixing. When combined with an optical frequency comb, by controlling the amplitude of the input signal and configuring the bias voltage of the Y-branch DP-MZM1, 5-line and 7-line frequency sparses can be generated respectively. Using the wavelength selection switch 7, this scheme can be extended to multi-channel, multi-band frequency converter systems with independent phase tuning capabilities, enabling parallel output of various mixing results.

[0033] like Figure 1 As shown, the reconfigurable mixer based on DP-MZM with phase shift and image suppression functions includes an LO harmonic mixing module and N synchronous phase shift and image suppression modules.

[0034] The LO harmonic mixing module is used to load the radio frequency (RF) signal and the local oscillator (LO) signal that need to be frequency-converted. Through modulation, the +1st order sideband of the RF signal and the local oscillator (LO) signal sideband that meet the frequency conversion requirements are obtained. The +1st order sideband of the RF signal and the local oscillator signal sideband that meet the frequency conversion requirements are combined to obtain orthogonally linearly polarized light of different wavelengths, which are then input to different synchronous phase shift and image suppression modules respectively.

[0035] The LO harmonic mixing module includes a semiconductor laser 1, a first polarization controller 2, a 1×2 optical coupler 3, a 90° polarization rotator 4, a first dual parallel Mach-Zehnder modulator 5 (DP-MZM1) for the Y branch, a second dual parallel Mach-Zehnder modulator 6 (DP-MZM2) for the X branch, a wavelength selection switch 7, a first erbium-doped fiber amplifier 8, a second erbium-doped fiber amplifier 9, a 1×N optical coupler 10, and a polarization combiner 11.

[0036] The semiconductor laser 1 (LD) generates linearly polarized light waves. The polarization direction and form of the linearly polarized light waves are adjusted by the first polarization controller 2 (PC1), outputting a linearly polarized light signal. The 1×2 optical coupler 3 splits the linearly polarized light signal into two equal-power optical signals. One of the optical signals is then adjusted by a 90° polarization rotator 4, ultimately obtaining a Y-polarized light signal and an X-polarized light signal. The Y-polarized light signal is modulated by the externally input local oscillator (LO) signal, which is then input to the first dual-parallel Mach-Zehnder modulator 5 in the Y branch to generate the various order sidebands of the local oscillator (LO) signal in optical signal form. The X-polarized light signal is modulated by the externally input radio frequency (RF) signal... The signal is modulated by the second dual-parallel Mach-Zehnder modulator 6 input to the X branch to obtain the +1st order sideband of the radio frequency (RF) signal in the form of an optical signal. The obtained RF signal +1st order sideband is amplified by the first erbium-doped fiber amplifier 8, and then divided into N RF signal +1st order sidebands by the 1×N optical coupler 10 with equal power. The wavelength selection switch 7 selects each order sideband of the local oscillator signal and outputs it to the second erbium-doped fiber amplifier 9 for amplification. Finally, the polarization combiner 11 (PBC) is used to combine one of the RF signal +1st order sidebands with the amplified local oscillator signal sideband into the same optical path to generate a path of orthogonally linearly polarized light with different wavelengths and transmit it to a synchronous phase shift and image suppression module.

[0037] In the configuration of the dual parallel Mach-Zehnder modulator DP-MZM, by changing the bias voltage of the first dual parallel Mach-Zehnder modulator 5 in the Y branch, the ±1st, ±2nd, ±3rd, or ±4th order local oscillator (LO) signal sidebands can be selectively retained, or the first dual parallel Mach-Zehnder modulator 5 in the Y branch can be used to generate 5-line and 7-line flat optical frequency combs respectively. At the same time, by adjusting the bias voltage and the amplitude of the radio frequency (RF) signal of the second dual parallel Mach-Zehnder modulator 6 in the X branch, the second dual parallel Mach-Zehnder modulator 6 in the X branch can be made to operate in the carrier-suppressed single-sideband (CS-SSB) modulation mode, retaining only the +1st order radio frequency (RF) signal sideband.

[0038] The N synchronous phase shift and image suppression modules represent N channels that can operate independently and have the same function. Each synchronous phase shift and image suppression module is used to introduce a specific phase shift into one orthogonally linearly polarized light input and convert it into an electrical signal output, while suppressing the image signal to obtain the final mixed signal.

[0039] The synchronous phase shift and mirror suppression module includes a synchronous phase shift module and a mirror suppression module;

[0040] The synchronous phase shift module is used to introduce a specific phase shift into one orthogonally linearly polarized light input and convert it into an electrical signal output, so as to achieve phase tuning of the output signal in the full range of 0~360°;

[0041] The image suppression module is used to suppress existing image signals;

[0042] The synchronous phase shift module includes a second polarization controller 12, a 50:50 polarization holding coupler 13, a first polarization analyzer 14, a second polarization analyzer 15, a first photodetector 16, and a second photodetector 17.

[0043] The second polarization controller 12 (PC2) converts one orthogonally linearly polarized light into one orthogonally circularly polarized light, and then splits it into two equal optical signals by a 50:50 polarization holding coupler 13. These signals are then input to the first analyzer 14 and the second analyzer 15 for beat frequency analysis. The first analyzer 14 and the second analyzer 15 adjust their respective polarization directions. and polarization direction The system generates two frequency conversion signals with phase tuning in the full range of 0~360°. Then, the first photodetector 16 and the second photodetector 17 convert the two frequency conversion signals from optical signals to electrical signals and input them to the image suppression module.

[0044] When the polarization direction between the first analyzer 14 and the second analyzer 15 of the upper and lower branches and polarization direction When the phase difference is 90° or 45°, double-balanced mixing or I / Q mixing functions can be achieved respectively;

[0045] The image suppression module uses a 90° electrical hybrid coupler 18 to introduce a 90° phase shift into one of the two input electrical signals, and then couples it with the other electrical signal to obtain the final mixed signal. The 90° electrical hybrid coupler 18 is used in the I / Q mixing function to realize the image suppression function in the downconversion mode.

[0046] like Figure 2As shown, the electrical spectrum of the PD output is displayed under different local oscillator conditions, indicating that the system has good multi-band up-conversion and down-conversion capability for RF signals; the measured waveforms of the 360° phase-tuned up-conversion and down-conversion signals are shown below. Figure 3 As shown, the results indicate that the amplitude fluctuation of the waveform is small in both cases and has a relatively flat amplitude response as the phase changes. Figure 4 The image rejection capability of the system was demonstrated. It can be observed that the intermediate frequency signal generated by the frequency conversion of the image signal is well suppressed, and the image rejection ratio (IRR) is 46.84dB, indicating that the system has a good ability to suppress image signals.

Claims

1. A reconfigurable mixer based on DP-MZM with phase shifting and image suppression functions, characterized in that, Includes an LO harmonic mixing module and N synchronous phase shift and image suppression modules; The LO harmonic mixing module is used to load the radio frequency signal and the local oscillator signal that need to be frequency-converted. Through modulation, the +1st order sideband of the radio frequency signal and the local oscillator signal sideband that meet the frequency conversion requirements are obtained. The +1st order sideband of the radio frequency signal and the local oscillator signal sideband that meet the frequency conversion requirements are combined to obtain orthogonally linearly polarized light of different wavelengths and are respectively input to different synchronous phase shift and image suppression modules. The N synchronous phase shift and image suppression modules represent N independently operating channels with the same function. Each synchronous phase shift and image suppression module is used to introduce a specific phase shift into one orthogonally linearly polarized light input and convert it into an electrical signal output, while suppressing the image signal to obtain the final mixed signal.

2. The reconfigurable mixer with phase shifting and image suppression functions based on DP-MZM according to claim 1, characterized in that, The LO harmonic mixing module includes a semiconductor laser, a first polarization controller, a 1×2 optical coupler, a 90° polarization rotator, a first dual parallel Mach-Zehnder modulator in the Y branch, a second dual parallel Mach-Zehnder modulator in the X branch, a wavelength selection switch, a first erbium-doped fiber amplifier, a second erbium-doped fiber amplifier, a 1×N optical coupler, and a polarization combiner. The semiconductor laser generates linearly polarized light waves. After the first polarization controller adjusts the polarization direction and polarization form of the linearly polarized light waves, a linearly polarized light signal is output. The 1×2 optical coupler splits the linearly polarized light signal into two optical signals with equal power. Then, a 90° polarization rotator adjusts one of the optical signals to finally obtain a Y-polarized optical signal and an X-polarized optical signal. The Y-polarized optical signal is modulated by the externally input local oscillator signal into the first dual-parallel Mach-Zehnder modulator of the Y branch to generate the sidebands of the local oscillator signal in the form of an optical signal. The X-polarized optical signal and the externally input radio frequency signal are modulated by the second dual-parallel Mach-Zehnder modulator of the X branch to obtain the +1 order sideband of the radio frequency signal in the form of an optical signal. The obtained RF signal +1st order sideband is amplified by the first erbium-doped fiber amplifier, and then split into N RF signal +1st order sidebands by a 1×N optical coupler with equal power. Wavelength selection switches are used to select each order sideband of the local oscillator signal and output to the second erbium-doped fiber amplifier for amplification. Finally, a polarization combiner is used to combine one of the RF signal +1st order sidebands with the amplified local oscillator signal sideband into the same optical path to generate a path of orthogonally linearly polarized light with different wavelengths and transmit it to a synchronous phase shift and image suppression module.

3. The reconfigurable mixer with phase shifting and image suppression functions based on DP-MZM according to claim 2, characterized in that, By changing the bias voltage of the first dual-parallel Mach-Zehnder modulator in the Y branch, the ±1st, ±2nd, ±3rd, or ±4th order local oscillator signal sidebands can be selectively retained, or the first dual-parallel Mach-Zehnder modulator in the Y branch can be used to generate 5-line and 7-line flat optical frequency combs respectively. At the same time, by adjusting the bias voltage and the amplitude of the radio frequency signal of the second dual-parallel Mach-Zehnder modulator in the X branch, the second dual-parallel Mach-Zehnder modulator in the X branch can be made to operate in the suppressed carrier single-sideband modulation mode, retaining only the +1st order radio frequency signal sideband.

4. The reconfigurable mixer with phase shifting and image suppression functions based on DP-MZM according to claim 1, characterized in that, The synchronous phase shift and mirror suppression module includes a synchronous phase shift module and a mirror suppression module; The synchronous phase shift module is used to introduce a specific phase shift into one orthogonally linearly polarized light input and convert it into an electrical signal output, so as to achieve phase tuning of the output signal in the full range of 0~360°; The image suppression module is used to suppress existing image signals.

5. The reconfigurable mixer with phase shifting and image suppression functions based on DP-MZM according to claim 4, characterized in that, The synchronous phase shift module includes a second polarization controller, a 50:50 polarization holding coupler, a first polarization analyzer, a second polarization analyzer, a first photodetector, and a second photodetector. The second polarization controller converts one orthogonally linearly polarized light beam into one orthogonally circularly polarized light beam, then splits it into two equal optical signals via a 50:50 polarization-holding coupler. These signals are then input to the first and second analyzers for beat frequency analysis. The first and second analyzers adjust their respective polarization directions... and polarization direction The system generates two frequency conversion signals with phase tuning across the entire range of 0~360°. Then, the first and second photodetectors convert the two frequency conversion signals from optical signals into electrical signals and input them into the image suppression module.

6. The reconfigurable mixer with phase shifting and image suppression functions based on DP-MZM according to claim 5, characterized in that, When the polarization direction between the first analyzer and the second analyzer and polarization direction When the phase difference is 90° or 45°, the double-balanced mixing or I / Q mixing function is realized respectively.

7. The reconfigurable mixer with phase shifting and image suppression functions based on DP-MZM according to claim 4, characterized in that, The image suppression module uses a 90° electrical hybrid coupler to introduce a 90° phase shift into one of the two input electrical signals, and then couples it with the other electrical signal to obtain the final mixed signal.

8. The reconfigurable mixer with phase shifting and image suppression functions based on DP-MZM according to claim 7, characterized in that, A 90° electric hybrid coupler is used in the I / Q mixing function to achieve image rejection in downconversion mode.

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