A dual-carrier frequency-controlled array signal generation device and method based on microwave photons

Abstract

The present invention discloses a dual-carrier frequency-controlled array signal generation device and method based on microwave photons. The device includes: a laser LD and a 1:N optical coupler; the optical carrier output by the LD is divided into N channels by the 1:N optical coupler, and each channel sequentially includes a polarization-modulated phase-shifted (PDM-DPMZM) module, a polarization controller PC, a polarizer Pol, an EDFA, a photodetector PD, and an antenna; wherein: the PDM-DPMZM includes a parallel X-DPMZM and Y-DPMZM, a polarization rotator PR, and a polarization beam combiner PBC; the X-DPMZM internally includes a main modulator and parallel MZMX_1 and MZMX_2; the Y-DPMZM internally includes a main modulator and parallel MZMY_1 and MZMY_2; the optical carriers output by MZMX_1 and MZMX_2 are modulated by the polarization rotator PR and combined with the optical carrier output by the Y-DPMZM by the polarization beam combiner PBC. The present invention not only simplifies system design and improves signal tunability, but also provides a new solution for achieving more effective distance and angle decoupling, laying a foundation for the future development of FDA radar technology.

Description

Technical Field

[0001] The present invention relates to the technical field of microwave photons and frequency-controlled arrays, and in particular to a dual-carrier frequency-controlled array signal generating device and method based on microwave photons. Background Art

[0002] Phased array (PA) technology has been widely used in many fields due to its high gain, flexible scanning, and excellent anti-interference capabilities. However, PA technology is limited by the frequency correlation of its signals, resulting in its spatial radiation pattern being solely dependent on angle, limiting its applications in distance-dependent applications. To overcome this limitation, frequency-diverse array (FDA) technology was introduced in 2006. By introducing a frequency offset between adjacent array elements, the spatial radiation pattern is made sensitive to both angle and distance, providing new possibilities for distance-dependent applications. Traditional FDA technology has an "S"-shaped spatial beam pattern, which results in energy dispersion and is susceptible to interference and noise, increasing the risk of detection by non-cooperative targets. Therefore, achieving a more focused beam pattern and decoupling the angle and distance dimensions are key to improving FDA performance. To date, researchers have mainly addressed this challenge through two methods: frequency offset optimization and array optimization.

[0003] Although existing research has provided a variety of solutions for the decoupling of FDA beam patterns, relevant literature is still relatively scarce, and traditional methods are subject to performance limitations in the electronic field when generating FDA signals. The emergence of microwave photonics (MWP) technology, with its unique advantages, provides new methods for the generation, transmission, and processing of radar signals. MWP technology has a wider bandwidth and highly adjustable frequency response, which significantly improves the flexibility and reconfigurability of microwave signal generation systems, indicating its great potential in signal generation for FDA radar systems. However, the currently reported microwave photonic FDA signal generation methods face challenges such as high system complexity and insufficient tunability, and there are difficulties in achieving distance and angle decoupling. Summary of the Invention

[0004] The purpose of the present invention is to provide a dual-carrier frequency-controlled array signal generation device and method based on microwave photons to overcome the problems existing in the prior art.

[0005] In order to achieve the above tasks, the present invention adopts the following technical solutions:

[0006] A microwave photon-based dual-carrier frequency-controlled array signal generation device includes: a laser (LD) and a 1:N optical coupler. The optical carrier output by the LD is divided into N channels by the 1:N optical coupler. Each channel includes a polarization multiplexing dual-parallel Mach-Zehnder modulator (PDM-DPMZM), a polarization controller (PC), a polarizer (Pol), an erbium-doped fiber amplifier (EDFA), a photodetector (PD), and an antenna. The radio frequency ports of the PDM-DPMZM are respectively connected to I / Q microwave signals and radio frequency signals provided by external signal sources. PDM-DPMZM includes parallel X-DPMZM and Y-DPMZM, a polarization rotator PR, and a polarization beam combiner PBC. The X-DPMZM internally contains a main modulator and parallel MZMX_1 and MZMX_2. The Y-DPMZM internally contains a main modulator and parallel MZMY_1 and MZMY_2. The optical carriers output by MZMX_1 and MZMX_2 are modulated by the polarization rotator PR and combined with the optical carrier output from the Y-DPMZM by the polarization beam combiner PBC.

[0007] A method for generating dual-carrier frequency-controlled array signals based on microwave photons, comprising:

[0008] Step 1: The continuous optical carrier output by the LD is injected into N channels respectively after passing through a 1:N optical coupler;

[0009] Step 2: In each channel, the optical carrier simultaneously enters the X-DPMZM and Y-DPMZM of the PDM-DPMZM for signal modulation. In the X-DPMZM, the DC bias of MZMX_2 is adjusted to operate at the minimum point. The optical carrier first implements suppressed carrier double-sideband modulation in MZMX_2, and the modulated signal is the RF signal. Simultaneously, MZMX_1 is unloaded and modulated to operate at the minimum point.

[0010] Step 3: In Y_DPMZM, I / Q microwave signals with a phase difference of 90 degrees are input to MZMY_1 and MZMY_2 respectively. At the same time, MZMY_1 and MZMY_2 are controlled to operate at the minimum point, and the main modulator operates at the orthogonal point, ultimately realizing suppressed carrier single sideband modulation (SSB-CS) of the optical carrier.

[0011] Step 4: The optical carriers output from MZMX_1 and MZMX_2 of the X-DPMZM are first modulated by the polarization rotator PR, and then combined with the optical carrier output from the Y-DPMZM by the polarization beam combiner PBC, thereby generating a polarization multiplexed signal of PDM-DPMZM.

[0012] In step 5, the polarization multiplexing signal of the PDM-DPMZM is polarized by the polarization controller PC and the polarizer Pol before being sent to the erbium-doped fiber amplifier EDFA for power compensation. Subsequently, the power-compensated optical carrier enters the photodetector PD for photoelectric signal conversion, ultimately generating a single-channel dual-carrier FDA signal that is sent to the antenna for transmission.

[0013] Furthermore, in X_DPMZM, the processing and output of the optical carrier are expressed as:

[0014] Assume that a continuous optical carrier enters each channel, denoted as E c (t) = E c exp(2πf c t); where E c and f c are the amplitude and frequency of the optical carrier, and t is the time parameter. In X-DPMZM, the optical carrier input to MZMX_2 is driven by the RF signal V RF (t) = V RF sin(2πf RF t) modulation, where V RF and f RF represent the amplitude and frequency of the RF signal respectively. When MZMX_1 is unloaded and the DC bias is adjusted to operate at the minimum point, the optical carrier output by X-DPMZM can be expressed as:

[0015]

[0016] Among them, m RF =πV RF / 2V π,MZMX_1 is the modulation index of MZMX_1, is the DC bias of MZMX_1, V π,MZMX_1 is the half-wave voltage of MZMX_1, V DC_RF is the DC bias input amplitude of MZMX_1, J n (·) represents the first kind n-th order Bessel function, e is a natural constant, and j is an imaginary unit;

[0017] By adjusting the DC bias MZMX_2 also works at the minimum point, that is, the optical signal output by X_DPMZM can be expressed as:

[0018]

[0019] Furthermore, in Y_DPMZM, the processing and output of the optical carrier are expressed as:

[0020] In Y_DPMZM, the optical carrier enters MZMY_1 and MZMY_2 respectively, and one of the I / Q microwave signals with a phase difference of 90 degrees is represented as V n_I (t) = V n sin(2πΔf n t), where V n and Δf n are the amplitude and frequency of the signal respectively; another I / Q microwave signal with a phase difference of 90 degrees is represented by V n_Q (t) = V n cos(2πΔf n t), the two I / Q microwave signals are injected into MZMY_1 and MZMY_2 respectively. By adjusting the bias points, MZMY_1 and MZMY_2 are respectively operated at the minimum point, and the main modulator operates at the orthogonal point. At this time, the optical signal output by Y_DPMZM is expressed as:

[0021]

[0022] Among them, m n is the modulation index of Y_DPMZM.

[0023] Furthermore, the optical carriers outputted by MZMX_1 and MZMX_2 of X_DPMZM are first modulated by the polarization rotator PR and then recorded as E X (t), and then combined with the optical carrier E output from Y-DPMZM Y (t) is combined by the polarization beam combiner PBC; at this time, the two signals with a 90° difference in polarization direction become polarization multiplexed signals, which can be expressed as:

[0024]

[0025] in, and Indicates different polarization modes.

[0026] Furthermore, using PC and Pol to combine two optical carriers with different polarization modes, the optical carrier after power compensation through EDFA can be expressed as:

[0027]

[0028] Among them, G EDFA is the compensation power of EDFA, α is the polarization azimuth, δ is the optical carrier E X (t), E Y (t) is the polarization phase difference.

[0029] Furthermore, the power-compensated EDFA optical signal is guided to the PD for photoelectric conversion, and the resulting photocurrent is expressed as:

[0030]

[0031] Among them, ∝ indicates positive correlation, is the amplitude of the dual-carrier FDA signal.

[0032] Compared with the prior art, the present invention has the following technical features:

[0033] The present invention can realize the generation of multi-channel, high-flatness FDA signals, and the generated radiation pattern realizes an "X"-shaped radiation pattern, which is very promising in distance and other related applications; the present invention can not only simplify system design and improve signal tunability, but also provide a new solution for achieving more effective distance and angle decoupling, providing strong support for the future development of FDA radar technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a structural diagram of the dual-carrier frequency-controlled array signal generating device based on microwave photons of the present invention;

[0035] Figure 2 This is the internal structure diagram of PDM-DPMZM;

[0036] Figure 3 Spectra of the PDM-DPMZM output signal; the I / Q microwave signal frequency in (a) is 1 MHz, and the I / Q microwave signal frequency in (b) is 1 GHz;

[0037] Figure 4 is the spectrum of the EDFA output signal;

[0038] Figure 5 is the spectrum of the PD output signal; the I / Q microwave signal frequency in (a) is 1 GHz, and the I / Q microwave signal frequency in (b) is 1 MHz;

[0039] Figure 6 is the spectrum of the 16-channel dual-carrier FDA signal;

[0040] Figure 7 (a)-(f) are the beam patterns formed by dual-carrier FDA signals with 4, 8, and 16 channels. DETAILED DESCRIPTION

[0041] See attached Figure 1The present invention provides a dual-carrier frequency-controlled array signal generating device based on microwave photons, comprising a laser diode (LD) and a 1:N optical coupler; the optical carrier output by the laser is divided into N channels by the 1:N optical coupler, each channel comprising a polarization multiplexing dual-parallel Mach-Zehnder modulator (PDM-DPMZM), a polarization controller (PC), a polarizer (Pol), an erbium-doped fiber amplifier (EDFA), a photodetector (PD) and an antenna, wherein:

[0042] The output port of the LD is connected to the input port of the 1:N coupler. The N output ports of the 1:N coupler are respectively connected to the input optical ports of N PDM-DPMZMs. Each output port of the PDM-DPMZM is connected to the input port of the PC. Each output port of the PC is connected to the input port of the Pol. Each output port of the Pol is connected to the input port of the EDFA. Each output port of the EDFA is connected to the input port of the PD. Finally, the output port of the PD is connected to the antenna. The RF port of the PDM-DPMZM is respectively connected to the I / Q microwave signal and RF signal provided by the external signal source.

[0043] In this scheme, PDM-DPMZM is an integrated and compact modulator with the following internal structure: Figure 2 The system comprises two parallel DPMZMs (X-DPMZM and Y-DPMZM), a polarization rotator (PR), and a polarization beam combiner (PBC). Each DPMZM contains a master modulator and two MZMs (MZMX_1, MZMX_2 or MZMY_1, MZMY_2). The master modulator in the X-DPMZM is used to create a phase difference between the optical carriers in MZMX_1 and MZMX_2, while the master modulator in the Y-DPMZM is used to create a phase difference between the optical carriers in MZMY_1 and MZMY_2. The four MZM modulators form the basic unit of the integrated modulator, which uses a DC signal for bias control to achieve modulation of different microwave signal formats.

[0044] On the basis of the above technical solution, the present invention further provides a method for generating dual-carrier frequency-controlled array signals based on microwave photons, comprising:

[0045] Step 1: The continuous optical carrier output by the LD passes through a 1:N optical coupler and is injected into N channels to generate dual-carrier FDA signals of different frequencies.

[0046] In step 2, in each channel, the optical carrier simultaneously enters the X-DPMZM and Y-DPMZM of PDM-DPMZM for signal modulation. In X_DPMZM, the DC bias of MZMX_2 is adjusted to make it operate at the minimum point. The optical carrier first implements suppressed carrier double-sideband modulation in MZMX_2, and the modulated signal is the RF signal. At the same time, MZMX_1 is unloaded and modulated to operate at the minimum point.

[0047] Step 3: In the Y_DPMZM, I / Q microwave signals with a 90-degree phase difference are input to MZMY_1 and MZMY_2, respectively. MZMY_1 and MZMY_2 are simultaneously controlled to operate at their minimum points, and the main modulator operates at the quadrature point, ultimately achieving single-sideband with carrier suppression modulation (SSB-CS) of the optical carrier.

[0048] In step 4, the optical carriers output from MZMX_1 and MZMX_2 of X_DPMZM are first modulated by the polarization rotator PR, and then combined with the optical carrier output from Y-DPMZM by the polarization beam combiner PBC, thereby generating the polarization multiplexing signal of PDM-DPMZM.

[0049] In step 5, the polarization multiplexing signal of the PDM-DPMZM is polarized by the polarization controller PC and the polarizer Pol before being sent to the erbium-doped fiber amplifier EDFA for power compensation. Subsequently, the power-compensated optical carrier enters the photodetector PD for photoelectric signal conversion, ultimately generating a single-channel dual-carrier FDA signal that is sent to the antenna for transmission.

[0050] The mathematical principles of the present invention are as follows:

[0051] Assume that a continuous optical carrier enters each channel, denoted as E c (t) = E c exp(2πf c t); where E c and f c are the amplitude and frequency of the optical carrier, and t is the time parameter. Subsequently, the optical carrier is input into the two DPMZMs (X-DPMZM and Y-DPMZM) in the PDM-DPMZM for modulation. In the X-DPMZM, the optical carrier input to MZMX_2 is modulated by the RF signal V RF (t) = V RF sin(2πfRF t) modulation, where V RF and f RF represent the amplitude and frequency of the RF signal respectively. When MZMX_1 is unloaded and the DC bias is adjusted to operate at the minimum point (the minimum point is the working state of carrier suppression), the optical carrier output by X-DPMZM can be expressed as:

[0052]

[0053] Among them, m RF =πV RF / 2V π,MZMX_1 is the modulation index of MZMX_1, is the DC bias of MZMX_1, V π,MZMX_1 is the half-wave voltage of MZMX_1, V DC_RF is the DC bias input amplitude of MZMX_1, J n (·) denotes the nth-order Bessel function of the first kind, e is a natural constant, and j is an imaginary unit.

[0054] By adjusting the DC bias MZMX_2 also works at the minimum point, that is, the optical signal output by X_DPMZM can be expressed as:

[0055]

[0056] In Y_DPMZM, the optical carrier enters MZMY_1 and MZMY_2 respectively for carrier suppressed single sideband modulation SSB-CS. Assuming that one of the I / Q microwave signals with a phase difference of 90 degrees can be expressed as V n_I (t) = V n sin(2πΔf n t), where V n and Δf n are the amplitude and frequency of the signal respectively; another I / Q microwave signal with a phase difference of 90 degrees can be expressed as V n_Q (t) = V n cos(2πΔf n t), the two I / Q microwave signals are injected into MZMY_1 and MZMY_2 respectively. By adjusting the bias points, MZMY_1 and MZMY_2 are respectively operated at the minimum point, and the main modulator operates at the orthogonal point. At this time, the optical signal output by Y_DPMZM can be expressed as:

[0057]

[0058] Among them, m n is the modulation index of Y_DPMZM.

[0059] Then, the optical carrier output from MZMX_1 and MZMX_2 of X_DPMZM is first modulated by the polarization rotator PR and then recorded as E X (t), and then combined with the optical carrier E output from Y-DPMZM Y (t) is combined by the polarization beam combiner PBC; at this time, the two signals with a 90° difference in polarization direction become polarization multiplexed signals, which can be expressed as:

[0060]

[0061] in, and Represent two different polarization modes respectively. Using PC and Pol to combine optical carriers with two different polarization modes, the optical signal after power compensation through EDFA can be expressed as:

[0062]

[0063] Among them, G EDFA is the compensation power of EDFA, α is the polarization azimuth, δ is the optical carrier E X (t), E Y (t) is the polarization phase difference.

[0064] Subsequently, the power-compensated EDFA optical signal is guided to the PD for photoelectric conversion. Ignoring the DC component and high-frequency component, the resulting photocurrent can be expressed as:

[0065]

[0066] Among them, ∝ indicates positive correlation, is the amplitude of the dual-carrier FDA signal.

[0067] From formula (8), we can see that the center frequencies of the generated dual-carrier FDA signals are f RF -Δf n and f RF +Δf n Therefore, the frequency of the generated FDA signal can be easily changed by adjusting the frequency of the RF signal and the I / Q microwave signal. Furthermore, the amplitude and phase can be adjusted using the PC in the link. Based on these characteristics, this method has flexible adjustability and can adapt to different FDA scenarios and modes.

[0068] Example:

[0069] In this example, the device includes: a narrow linewidth tunable laser source, an integrated modulator PDM-DPMZM, a PC, a Pol, an EDFA, an optical spectrum analyzer, a spectrum analyzer, an oscilloscope, a signal generator, an arbitrary waveform generator AWG, and a DC power supply.

[0070] The continuous-wave optical carrier signal for each path is generated by a narrow-linewidth tunable laser source. This laser source operates in a frequency range of 191.50 to 196.25 THz, with an adjustable frequency accuracy of 0.01 nm and a maximum output power of 13.6 dBm. The integrated PDM-DPMZM modulator, the core component of the experimental link, implements SSB-CS modulation of microwave signals and DSB modulation of RF signals. PC and Pol control the polarization states of the PDM-DPMZM output signals. An EDFA with automatic power control and automatic gain control modes is used to compensate for power losses during the entire experimental process. Finally, the amplified optical signal is injected into the PD for optical detection. In the entire experimental test system, the optical signal is monitored by an optical spectrum analyzer, and the electronic signal is observed by a spectrum analyzer or oscilloscope. The microwave signal injected into the PDM-DPMZM is generated by a signal generator, while the I / Q microwave signal with a 90-degree phase difference is generated by an arbitrary waveform generator. A DC power supply provides the DC signal.

[0071] In the example, the specific implementation steps of the method are:

[0072] In step 1, the operating frequency of the LD is 193.4THz and the output power is 13.6dBm. In X-DPMZM, the RF signal generated by the signal generator operates at a frequency of 10GHz and a power level of 15dBm. By adjusting the DC bias of the two sub-modulators so that they operate at the minimum point, DSB modulation is achieved. Similarly, in Y-DPMZM, the I / Q microwave signal generated by the AWG operates at a frequency of 1MHz, with a power level of 10dBm and a phase difference of 90 degrees. By adjusting the DC bias output of the DC source, the two sub-modulators of the DPMZM are set to operate at their minimum point, while the main modulator is aligned at the orthogonal point. With this configuration, an SSB-CS signal can be achieved. Finally, the spectrum of the optical signal containing two polarization states output by PDM-DPMZM is as follows Figure 3 To better observe the SSB-CS component, the AWG is set to output a 1 GHz I / Q microwave signal. In this configuration, the spectrum of the PDM-DPMZM output is shown in (a). Figure 3 As shown in (b).

[0073] Step 2: After the optical signal from the PDM-DPMZM is precisely polarized and coupled with the PC and Pol states, it is injected into the EDFA for power compensation. Considering the input power limit of the PD, the EDFA is set to automatic power control mode to ensure that the output power is stable at 5dBm. The spectrum of the EDFA output signal is as follows: Figure 4 shown

[0074] In step 3, the carefully adjusted optical signal, i.e. the power compensation after EDFA, is directly injected into the PD with a high responsivity of 0.6A / W for photoelectric detection. The generated dual-carrier FDA signal is observed using a spectrum analyzer, as shown in Figure 5 shown.

[0075] Step 4: Adjust the frequency of the I / Q microwave signal starting from 1MHz and increasing it to 16MHz in 1MHz steps. The PD generates a dual-carrier FDA signal through 16 channels, such as Figure 6 Inspection of the figure shows that the frequencies of these dual-carrier FDA signals for the 16 channels are centered around 10 GHz, with each channel having a frequency offset of n × 1 MHz, where n represents the respective channel number.

[0076] Step 5: Use an oscilloscope to take 4, 8, and 16 channels of dual-carrier FDA signals, and use MATLAB to perform pattern beamforming. The resulting patterns are as follows: Figure 7 shown.

[0077] In summary, the microwave photon-based dual-carrier frequency-controlled array signal generation device and method of the present invention are simple and easy to implement, and can generate dual-carrier FDA signals with high flatness and high spurious suppression ratio within a large bandwidth. The present invention has great prospects in applications such as frequency-controlled array radar.

[0078] In the present invention, the implementation of DSB and SSB-CS modulation is not limited to PDM-DPMZM, and two DPMZMs can also be used to achieve the same effect.

[0079] In the present invention, the signal loaded into the PDM-DPMZM is not limited to a single-frequency signal, but may also be other signals such as radar, communication, etc., such as a linear frequency modulation signal, a phase coded signal or a vector modulation signal.

[0080] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. A method for generating dual-carrier frequency-controlled array signals based on microwave photons, characterized in that: The method is implemented on the basis of a dual-carrier frequency-controlled array signal generating device; the device comprises a laser LD and a 1:N optical coupler; the optical carrier output by the LD is divided into N channels by the 1:N optical coupler, and each channel comprises a polarization multiplexing dual parallel Mach-Zehnder modulator PDM-DPMZM, a polarization controller PC, a polarizer Pol, an erbium-doped fiber amplifier EDFA, a photodetector PD and an antenna in sequence; wherein: the radio frequency ports of the PDM-DPMZM are respectively connected to the I / Q microwave signal and the radio frequency signal provided by the external signal source The PDM-DPMZM includes parallel X-DPMZM and Y-DPMZM, a polarization rotator PR, and a polarization beam combiner PBC. The X-DPMZM internally contains a main modulator and parallel MZMX_1 and MZMX_2. The Y-DPMZM internally contains a main modulator and parallel MZMY_1 and MZMY_2. The optical carriers output by MZMX_1 and MZMX_2 are modulated by the polarization rotator PR and combined with the optical carrier output by the Y-DPMZM by the polarization beam combiner PBC. The method comprises: Step 1: The continuous optical carrier output by the LD is injected into N channels respectively after passing through a 1:N optical coupler; Step 2: In each channel, the optical carrier simultaneously enters the X-DPMZM and Y-DPMZM of PDM-DPMZM for signal modulation; in X_DPMZM, the DC bias of MZMX_2 is adjusted to make it work at the minimum point. The optical carrier first implements suppressed carrier double-sideband modulation in MZMX_2, and the modulated signal is the RF signal. RF ; At the same time, MZMX_1 is unloaded and modulated to operate at the minimum point; Step 3: In Y_DPMZM, I / Q microwave signals with a phase difference of 90 degrees are input to MZMY_1 and MZMY_2 respectively. At the same time, MZMY_1 and MZMY_2 are controlled to operate at the minimum point, and the main modulator operates at the orthogonal point, ultimately realizing suppressed carrier single sideband modulation (SSB-CS) of the optical carrier. Step 4: The optical carriers output from MZMX_1 and MZMX_2 of the X-DPMZM are first modulated by the polarization rotator PR, and then combined with the optical carrier output from the Y-DPMZM by the polarization beam combiner PBC, thereby generating a polarization multiplexed signal of PDM-DPMZM. In step 5, the polarization multiplexing signal of the PDM-DPMZM is polarized by the polarization controller PC and the polarizer Pol before being sent to the erbium-doped fiber amplifier EDFA for power compensation. Subsequently, the power-compensated optical carrier enters the photodetector PD for photoelectric signal conversion, ultimately generating a single-channel dual-carrier FDA signal that is sent to the antenna for transmission.

2. The method for generating dual-carrier frequency-controlled array signals based on microwave photons according to claim 1, characterized in that: In X_DPMZM, the processing and output of the optical carrier are expressed as: Assume that a continuous optical carrier enters each channel, expressed as ;in and are the amplitude and frequency of the optical carrier, t is the time parameter; in X-DPMZM, the optical carrier input to MZMX_2 is replaced by the RF signal Modulation, where and represent the amplitude and frequency of the RF signal respectively. When MZMX_1 is unloaded and the DC bias is adjusted to operate at the minimum point, the optical carrier output by X-DPMZM can be expressed as: (1) in, is the modulation index of MZMX_1, is the DC bias of MZMX_1, is the half-wave voltage of MZMX_1, is the DC bias input amplitude of MZMX_1, represents the nth-order Bessel function of the first kind, is a natural constant, is an imaginary unit; By adjusting the DC bias , MZMX_2 also works at the minimum point, that is, the optical signal output by X_DPMZM can be expressed as: (2)。 3. The method for generating dual-carrier frequency-controlled array signals based on microwave photons according to claim 2, characterized in that: In Y_DPMZM, the processing and output of the optical carrier are expressed as: In Y_DPMZM, the optical carrier enters MZMY_1 and MZMY_2 respectively, and one of the I / Q microwave signals with a phase difference of 90 degrees is expressed as ,in and are the amplitude and frequency of the signal respectively; another I / Q microwave signal with a phase difference of 90 degrees is expressed as , these two I / Q microwave signals are injected into MZMY_1 and MZMY_2 respectively; by adjusting the bias point, MZMY_1 and MZMY_2 are respectively operated at the minimum point, and the main modulator operates at the orthogonal point. At this time, the optical signal output by Y_DPMZM is expressed as: (3) in, is the modulation index of Y_DPMZM.

4. The method for generating dual-carrier frequency-controlled array signals based on microwave photons according to claim 3, characterized in that: The optical carriers output by MZMX_1 and MZMX_2 of X_DPMZM are first modulated by the polarization rotator PR and then recorded as , and then with the optical carrier output from Y-DPMZM The polarization beam combiner PBC combines the two signals with a 90° difference in polarization direction into a polarization multiplexed signal, which can be expressed as: (4) in, and Indicates different polarization modes.

5. The method for generating dual-carrier frequency-controlled array signals based on microwave photons according to claim 4, characterized in that: Using PC and Pol to combine two optical carriers with different polarization modes, the optical carrier after power compensation through EDFA can be expressed as: (5) in, is the compensation power of EDFA, is the polarization azimuth, Optical carrier 、 polarization phase difference.

6. The method for generating dual-carrier frequency-controlled array signals based on microwave photons according to claim 5, characterized in that: The power-compensated EDFA optical signal is guided to the PD for photoelectric conversion, and the resulting photocurrent is expressed as: (6) in, Indicates positive correlation, is the amplitude of the dual-carrier FDA signal.

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