A space-based gravitational wave detection signal simulation system including a phase-locking mechanism

Abstract

The present invention discloses a space-based gravitational wave detection signal simulation system including a phase-locking mechanism, the system comprising: a phase-locking mechanism signal simulation model, a phase-locking scheme design module and a detection formation full-link signal output module; wherein the phase-locking mechanism signal simulation model comprises three spacecraft simulation platforms with the same structure, two optical platforms are arranged on each spacecraft simulation platform, two measurement masses are arranged on each optical platform, as well as one scientific interferometer, one test mass interferometer and one reference interferometer; the phase-locking scheme design module is used for including six phase-locking sequence selections and six phase-locking main laser selections, forming a total of 36 phase-locking schemes; the detection formation full-link signal output module is used for selecting a phase-locking scheme according to a specified main laser, realizing laser phase locking between different optical platforms of different spacecraft and realizing phase output of each interferometer.

Description

Technical Field

[0001] The present invention belongs to the field of computer technology, and in particular relates to a space-based gravitational wave detection signal simulation system including a phase-locking mechanism. Background Art

[0002] The gravitational wave detection formation includes three spacecraft and six optical platforms. Each optical platform includes a scientific interferometer, a test mass interferometer and a reference interferometer. It uses segmented heterodyne interferometry to measure the impact of gravitational waves on space-time disturbances and invert the wave source parameters. Space gravitational wave detection uses weak light phase-locked amplification technology to overcome the laser attenuation problem of ultra-long-distance transmission. It requires laser phase locking between the three spacecraft and multiple interferometers in the detection formation, which is an important part of the full-link simulation. Due to the extremely complex physical mechanism of phase locking and the transmission process of system noise in the phase-locked loop, modeling and simulation are difficult. The full-link signal construction model of the detection formation including the phase-locked mechanism has not yet been constructed, making it difficult to effectively analyze and evaluate the system frequency parameter optimization and offset frequency setting scheme. Summary of the invention

[0003] The purpose of the present invention is to overcome the defects of the prior art, consider various noise coupling factors, and construct a space-based gravitational wave detection signal simulation method and system including a phase-locked mechanism for space gravitational wave detection.

[0004] In order to achieve the above-mentioned purpose, the present invention proposes a space-based gravitational wave detection signal simulation system including a phase-locking mechanism, the system comprising: a phase-locking mechanism signal simulation model, a phase-locking scheme design module and a detection formation full-link signal output module; wherein,

[0005] The phase-locked mechanism signal simulation model includes three spacecraft simulation platforms with the same structure, two optical platforms are arranged on each spacecraft simulation platform, two measurement masses are arranged on each optical platform, and one scientific interferometer, one test mass interferometer and one reference interferometer are arranged;

[0006] The phase-locking scheme design module is used to include 6 phase-locking sequence selections and 6 phase-locking main laser selections, forming a total of 36 phase-locking schemes;

[0007] The detection formation full-link signal output module is used to select a phase-locking scheme according to a specified main laser, realize laser phase locking between different optical platforms of different spacecraft, and realize phase output of each interferometer.

[0008] Preferably, the three spacecraft simulation platforms with the same structure are arranged in a counterclockwise direction, namely the first spacecraft, the second spacecraft and the third spacecraft simulation platform. The angle between the two optical platforms arranged on each spacecraft simulation platform is 60 degrees. The six optical platforms form an equilateral triangle. Lasers A and B and mass blocks TM1 and TM2 are placed inside the two optical platforms of the first spacecraft simulation platform. Lasers C and D and mass blocks TM3 and TM4 are placed inside the two optical platforms of the second spacecraft simulation platform. Lasers E and F and mass blocks TM5 and TM6 are placed inside the two optical platforms of the third spacecraft simulation platform. Each optical platform respectively transmits and receives lasers to two adjacent optical platforms.

[0009] Preferably, the six phase-locked sequences include: PL-Seq1, PL-Seq2, PL-Seq3, PL-Seq4, PL-Seq5 and PL-Seq6, wherein:

[0010] Select Laser A as the main laser,

[0011] PL-Seq1: Laser B is phase-locked to laser A received by the optical platform, laser C is phase-locked to laser B received by the optical platform, laser D is phase-locked to laser C received by the optical platform, laser E is phase-locked to laser D received by the optical platform, and laser F is phase-locked to laser E received by the optical platform;

[0012] PL-Seq2: Laser B is phase-locked to laser A received by the optical platform, laser C is phase-locked to laser B received by the optical platform, laser D is phase-locked to laser C received by the optical platform, laser E is phase-locked to laser D received by the optical platform, and laser F is phase-locked to laser A received by the optical platform;

[0013] PL-Seq3: Laser B is phase-locked to laser A received by the optical platform, laser C is phase-locked to laser B received by the optical platform, laser D is phase-locked to laser C received by the optical platform, laser E is phase-locked to laser F received by the optical platform, and laser F is phase-locked to laser A received by the optical platform;

[0014] PL-Seq4: Laser B is phase-locked to laser A received by the optical platform, laser C is phase-locked to laser B received by the optical platform, laser D is phase-locked to laser E received by the optical platform, laser E is phase-locked to laser F received by the optical platform, and laser F is phase-locked to laser A received by the optical platform;

[0015] PL-Seq5: Laser B is phase-locked to laser A received by the optical platform where it is located, laser C is phase-locked to laser D received by the optical platform where it is located, laser D is phase-locked to laser E received by the optical platform where it is located, laser E is phase-locked to laser F received by the optical platform where it is located, and laser F is phase-locked to laser A received by the optical platform where it is located;

[0016] PL-Seq6: Laser B is phase-locked to laser C received by the optical platform where it is located, laser C is phase-locked to laser D received by the optical platform where it is located, laser D is phase-locked to laser E received by the optical platform where it is located, laser E is phase-locked to laser F received by the optical platform where it is located, and laser F is phase-locked to laser A received by the optical platform where it is located.

[0017] Preferably, the 36 phase-locking schemes include:

[0018] <PL-Seq1, master laser A>, <PL-Seq2, master laser A>, <PL-Seq3, master laser A>, <PL-Seq4, master laser A>, <PL-Seq5, master laser A>, <PL-Seq6, master laser A>; <PL-Seq1, master laser B>, <PL-Seq2, master laser B>, <PL-Seq3, master laser B>, <PL-Seq4, master laser B>, <PL-Seq5, master laser B>, <PL-Seq6, master laser B>; <PL-Seq1, master laser D>, <PL-Seq2, master laser D>, <PL-Seq3, master laser D>, <PL-Seq4, master laser D>, <PL-Seq5, master laser D>, <PL-Seq6, master laser D>; <PL-Seq1, master laser E>, <PL-Seq2, master laser E>, <PL-Seq3, master laser E>, <PL-Seq4, master laser E>, <PL-Seq5, master laser E>, <PL-Seq6, master laser E>; <PL-Seq1, master laser F>, <PL-Seq2, master laser F>, <PL-Seq3, master laser F>, <PL-Seq4, master laser F>, <PL-Seq5, master laser F>, <PL-Seq6, master laser F>.

[0019] Preferably, the detection formation full-link signal output module selects the phase-locking scheme <PL-Seq3, master laser A> according to the specified master laser A, and respectively collects the phase signals output by each laser after phase-locking:

[0020]

[0021] Among them, and respectively represent the phase outputs of lasers B, C, D, E, and F after phase-locking; represents the laser frequency noise of laser A,

[0022] Respectively represent the optical platform noise of the optical platform where lasers A, B, C, D, E, and F are located, and They represent the readout noise and other noise of the optical platform where laser B is located; and They represent the readout noise and other noise of the optical platform where the laser C is located; and They represent the readout noise and other noise of the optical platform where the laser D is located;

[0023] and They represent the readout noise and other noise of the optical platform where the laser E is located; and They represent the readout noise and other noise of the optical platform where the laser F is located;

[0024] φ GW12 (t) and φ GW13 (t) represent the laser phase changes caused by gravitational wave signals;

[0025] and They represent the phase changes of laser C and laser F caused by the gravitational wave signal, represents the noise introduced by the phase-locking mechanism during the process of laser B being phase-locked to laser A, represents the noise introduced by the phase-locking mechanism when laser C is phase-locked to laser B, represents the noise introduced by the phase-locking mechanism when laser D is phase-locked to laser C. represents the noise introduced by the phase-locking mechanism during the process of laser E being phase-locked to laser F, It represents the noise introduced by the phase-locking mechanism when laser F is phase-locked to laser A.

[0026] Preferably,

[0027]

[0028]

[0029]

[0030]

[0031] Among them, L -1 {·} represents the inverse Laplace transform, φ GW12 (s), φ GW13(s) represents the frequency-domain representation of the time-series gravitational wave signal.

[0032] Preferably, the full-link phase-locking process of the phase-locking scheme <PL-Seq3, master laser A> includes:

[0033] Left side:

[0034] Step 1: Transmit laser A to the second optical platform through an optical fiber, interfere with laser B in the reference interferometer. After interference, make laser B phase-locked to laser A through a feedback control loop;

[0035] Step 2: Transmit the phase-locked laser B to the third optical platform, interfere with laser C in the scientific interferometer. After interference, make laser C phase-locked to the received laser B through a feedback control loop;

[0036] Step 3: Transmit the phase-locked laser C to the fourth optical platform through an optical fiber, interfere with laser D in the reference interferometer. After interference, make laser D phase-locked to laser C through a feedback control loop;

[0037] Right side:

[0038] Step 1: Transmit laser A to the sixth optical platform and interfere with laser F in the scientific interferometer. After interference, make laser F phase-locked to laser A through a feedback control loop;

[0039] Step 2: Transmit the phase-locked laser F to the fifth optical platform through an optical fiber, interfere with laser E in the reference interferometer. After interference, make laser E phase-locked to laser F through a feedback control loop.

[0040] Compared with the prior art, the advantages of the present invention are:

[0041] 1. The present invention constructs a more comprehensive phase-locking scheme, considering 6 phase-locking sequences and master lasers for phase-locking, with a total of 36 phase-locking setting schemes.

[0042] 2. The present invention constructs a full-link phase signal model of the detection formation including a phase-locking mechanism, and realizes the addition of various noise phase signals including laser frequency noise, optical platform noise, readout noise, acceleration noise, other noises, etc.

[0043] 3. The present invention realizes the propagation path of the interference phase signal with multiple noise couplings, which can lay a theoretical foundation for further analysis by subsequent researchers. Description of the Drawings

[0044] Figure 1 Are 6 phase-locking schemes with master laser A

[0045] Figure 2 is a schematic diagram of phase locking and a schematic diagram of a laser link. Among them, Figure 2(a) is a schematic diagram of a phase locking scheme, and Figure 2(b) is a schematic diagram of a laser link;

[0046] Figure 3 It is a display diagram of the full-link phase locking mechanism of the phase locking scheme <PL-Seq3, main laser A>;

[0047] Figure 4 It is a display diagram of each interference link;

[0048] Figure 5 It is the signal output of the scientific interferometer;

[0049] Figure 6 It is the signal output of the test mass interferometer;

[0050] Figure 7 It is the signal output of the reference interferometer. Specific implementation mode

[0051] Due to the relative motion between satellites, the laser frequency will be affected by the Doppler frequency shift, causing the interference beat frequency to fluctuate within a certain range. To avoid the fluctuating beat frequency exceeding the detection range of the photodiode, an offset frequency is usually added through a mixer during the weak light phase locking process. To keep the beat frequencies within all six optical platforms of the entire constellation within a reasonable range, one of the six optical platforms is selected as the main optical platform, and the laser emitted by it is the main laser. According to the different whole-satellite phase locking sequences and main phase-locked lasers, different phase locking schemes can be divided. There are 6 phase locking sequences in total, and all 6 lasers can be used as the main laser, so a total of 36 phase locking schemes are available for selection.

[0052] To realize the simulation of space-based gravitational wave detection signals including a phase locking mechanism, the present invention proposes a method and system for simulating space-based gravitational wave detection signals including a phase locking mechanism.

[0053] The method includes:

[0054] Step 1: Construct a signal simulation model of the phase locking mechanism

[0055] As an improvement of the above method, the description of the phase locking mechanism in step 1 is as follows:

[0056] Assume that the phase locking mechanism feedback control loop uses a temperature controller and a PZT controller to feedback control the slave laser and lock it to the main laser. The open-loop transfer function of the phase locking mechanism feedback control loop is represented by F(s). Assume that LASER 1 and LASER2s represent the main laser and the slave laser respectively, and their phase signals are represented by and respectively, represents the phase of the two laser interference signals, which includes not only the phase change caused by gravitational waves, but also the phase change caused by various noises. The expression is as follows

[0057]

[0058] in, and They represent the phase change caused by gravitational wave signal, laser frequency noise, optical platform noise and other noises respectively, and D represents the inter-satellite laser transmission delay.

[0059] The phase signal output after Laser 2s phase locking is constructed as follows

[0060]

[0061] in,

[0062]

[0063] L -1 {·} denotes inverse Laplace transform.

[0064] Step 2: Select a phase-locking scheme

[0065] As an improvement of the above method, the step 2 specifically includes:

[0066] The phase-locking scheme includes 6 phase-locking sequence selections and 6 phase-locking main laser selections, which constitute a total of 36 phase-locking schemes;

[0067] The three spacecraft are defined as spacecraft 1, spacecraft 2 and spacecraft 3; A, B, C, D, E, and F represent six main lasers; A and B are placed inside the two optical platforms of spacecraft 1, C and D are placed inside the two optical platforms of spacecraft 2, and E and F are placed inside the two optical platforms of spacecraft 3. The entire detection constellation contains a total of six optical platforms, each of which transmits and receives lasers to two adjacent optical platforms.

[0068] The six phase-locked sequences are denoted as PL-Seq1, PL-Seq2, PL-Seq3, PL-Seq4, PL-Seq5 and PL-Seq6.

[0069] Select laser A as the main laser, and the six phase-locking sequences are described as follows:

[0070] PL-Seq1: Laser B is phase-locked to laser A received by this optical platform, laser C is phase-locked to laser B received by this optical platform, laser D is phase-locked to laser C received by this optical platform, laser E is phase-locked to laser D received by this optical platform, and laser F is phase-locked to laser E received by this optical platform.

[0071] PL-Seq2: Laser B is phase-locked to laser A received by this optical platform, laser C is phase-locked to laser B received by this optical platform, laser D is phase-locked to laser C received by this optical platform, laser E is phase-locked to laser D received by this optical platform, and laser F is phase-locked to laser A received by this optical platform.

[0072] PL-Seq3: Laser B is phase-locked to laser A received by this optical platform, laser C is phase-locked to laser B received by this optical platform, laser D is phase-locked to laser C received by this optical platform, laser E is phase-locked to laser F received by this optical platform, and laser F is phase-locked to laser A received by this optical platform.

[0073] PL-Seq4: Laser B is phase-locked to laser A received by this optical platform, laser C is phase-locked to laser B received by this optical platform, laser D is phase-locked to laser E received by this optical platform, laser E is phase-locked to laser F received by this optical platform, and laser F is phase-locked to laser A received by this optical platform.

[0074] PL-Seq5: Laser B is phase-locked to laser A received by this optical platform, laser C is phase-locked to laser D received by this optical platform, laser D is phase-locked to laser E received by this optical platform, laser E is phase-locked to laser F received by this optical platform, and laser F is phase-locked to laser A received by this optical platform.

[0075] PL-Seq6: Laser B is phase-locked to laser C received by this optical platform, laser C is phase-locked to laser D received by this optical platform, laser D is phase-locked to laser E received by this optical platform, laser E is phase-locked to laser F received by this optical platform, and laser F is phase-locked to laser A received by this optical platform.

[0076] The 36 phase-locking schemes are <PL-Seq1, main laser A>, <PL-Seq2, main laser A>,

[0077] <PL-Seq3, Master Laser A>, <PL-Seq4, Master Laser A>, <PL-Seq5, Master Laser A>, <PL-Seq6, Master Laser A>; <PL-Seq1, Master Laser B>, <PL-Seq2, Master Laser B>, <PL-Seq3, Master Laser B>, <PL-Seq4, Master Laser B>, <PL-Seq5, Master Laser B>, <PL-Seq6, Master Laser B>; <PL-Seq1, Master Laser D>, <PL-Seq2, Master Laser D>, <PL-Seq3, Master Laser D>, <PL-Seq4, Master Laser D>, <PL-Seq5, Master Laser D>, <PL-Seq6, Master Laser D>; <PL-Seq1, Master Laser E>, <PL-Seq2, Master Laser E>, <PL-Seq3, Master Laser E>, <PL-Seq4, Master Laser E>, <PL-Seq5, Master Laser E>, <PL-Seq6, Master Laser E>; <PL-Seq1, Master Laser F>, <PL-Seq2, Master Laser F>, <PL-Seq3, Master Laser F>, <PL-Seq4, Master Laser F>, <PL-Seq5, Master Laser F>, <PL-Seq6, Master Laser F>;

[0078] Step 3: Construct a full-link signal model of the detection formation including the phase-locked scheme

[0079] Use <PL-Seq3, Master Laser A>, and use the interference signal of Laser C and Laser F with a scientific interferometer as the feedback signal to achieve the locking of the local laser phase and the received laser phase. Use the readout signal of the reference interferometer of Laser B, Laser D, and Laser E as the feedback signal to achieve the laser phase locking between different optical platforms of the same spacecraft.

[0080] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0081] Embodiment

[0082] An embodiment of the present invention proposes a space-based gravitational wave detection signal simulation system including a phase-locked mechanism, which system comprises: a phase-locked mechanism signal simulation model, a phase-locked scheme design module, and a detection formation full-link signal output module; wherein, the phase-locked mechanism signal simulation model includes 3 spacecraft simulation platforms with the same structure, each spacecraft simulation platform is provided with 2 optical platforms, each optical platform is provided with 2 measurement masses, as well as 1 scientific interferometer, 1 test mass interferometer, and 1 reference interferometer; the phase-locked scheme design module is used to include 6 selections of phase-locked sequences and 6 selections of phase-locked main lasers, which together form 36 phase-locked schemes; the detection formation full-link signal output module is used to select a phase-locked scheme according to the specified main laser, realize laser phase locking between different optical platforms of different spacecraft, and realize the phase output of each interferometer.

[0083] In the selection of the phase-locked scheme, if the phase-locked main laser does not change, there are the following six phase-locked schemes, as Figure 1 shown, numbered (a)-(f) respectively. Only one phase-locked main laser is shown. In fact, all 6 lasers can be used as the main laser, so there are a total of 36 phase-locked schemes to choose from. Among them, phase-locked scheme (c) is usually adopted in the current mission.

[0084] Taking the phase-locked scheme <PL-Seq3, main laser A> as an example for detailed introduction, Figure 2 is a phase-locked schematic diagram and a laser link schematic diagram. As shown in Figure 2(a), in this phase-locked scheme, laser A is used as the phase-locked main laser, and the other lasers are used as slave lasers. The inter-satellite time sequence Doppler frequency shift is set to f doppler,1,2 f doppler,1,2 and f doppler,1,2 . As shown in Figure 2(b), each optical platform is equipped with two test masses, named TM1-TM6 respectively, and the six interference links are L1, L1s, L2, L2s, L3, and L3s. Among them and represent direction vectors.

[0085] Without considering the phase-locked loop, the output signal expressions of the three interferometers on the optical platform where the main laser A is located are as shown in the formula.

[0086]

[0087] Among them,

[0088]

[0089] Among them, and respectively represent the output signals of the scientific interferometer, the test mass interferometer, and the reference interferometer on this optical platform; φ GW31(t) represents the phase change caused by the gravitational wave signal; and represent the laser frequency noise of Laser A and Laser F respectively; and represent the optical platform noise of OB A and OB F respectively; and They represent the readout noise, acceleration noise, laser pointing jitter noise, advance pointing optical path noise, breathing angle compensation optical path noise and other noises introduced in the optical platform, respectively, among which the acceleration noise only exists in the test quality interferometer; represents the set of phase changes caused by laser pointing jitter noise, advance pointing optical path noise, breathing angle compensation optical path noise and other noises in the scientific interferometer of the optical platform; D 31 represents the inter-satellite transmission delay operator, and It represents the phase change caused by the laser frequency noise from OB F and the optical platform noise received by the optical platform. Similarly, to simplify the formula, and They respectively represent the difference in phase change caused by the laser frequency noise of Laser F and the noise of the optical platform where Laser F is located received by the optical platform and the laser frequency noise of Laser A and the noise of the optical platform where Laser A is located; and They respectively represent the difference in phase change caused by the laser frequency noise of Laser B received by the optical platform where Laser A is located, the noise of the optical platform where Laser B is located, and the laser frequency noise of Laser A and the noise of the optical platform where Laser A is located.

[0090] After phase locking, the output phase signals of each laser are as follows:

[0091]

[0092] in, and Respectively represent the phase outputs of each laser after phase locking; represents the laser frequency noise of laser x, The optical platform noise of the optical platform where the laser x is located, represents the readout noise of the optical platform where the laser x is located, represents other noise on the optical platform where the laser x is located, where x∈[A,B,C,D,E,F]. It represents the phase signal introduced by the phase-locking mechanism during the process of laser n being phase-locked to laser m, such as Indicates the phase signal introduced by the phase-locking mechanism during the process of locking laser F to laser A. In the case of selecting the phase-locking scheme <PL-Seq3, master laser A>, There are a total of five, namely and Spacecraft S / C 1:

[0093] The optical platform where laser B is located

[0094] Phase outputs of each interferometer before phase locking:

[0095]

[0096] The output phase after locking laser B is as follows:

[0097]

[0098] Among them,

[0099]

[0100] The signal outputs of each interferometer on the optical platform where laser B is located after phase locking are as follows:

[0101]

[0102] At this time, the phase of the laser output after phase locking needs to be used for calculation.

[0103] Spacecraft S / C 2:

[0104] The optical platform where laser C is located

[0105] Phase outputs of each interferometer before locking the weak light:

[0106]

[0107] The output phase after locking laser C is as follows:

[0108]

[0109] Among them,

[0110]

[0111] The signal outputs of each interferometer on the optical platform where laser C is located after phase locking are as follows:

[0112]

[0113] The optical platform where laser D is located

[0114] Phase outputs of each interferometer before phase locking:

[0115]

[0116] The output phase of the laser D after phase locking is as follows:

[0117]

[0118] in,

[0119]

[0120] After phase locking, the signal outputs of each interferometer on the optical platform where laser D is located are as follows:

[0121]

[0122] Spacecraft S / C 3:

[0123] Optical platform where laser E is located

[0124] Phase output of each interferometer before phase locking:

[0125]

[0126] The output phase of laser E after phase locking is as follows:

[0127]

[0128] in,

[0129]

[0130] After phase locking, the signal outputs of each interferometer on the optical platform where laser E is located are as follows:

[0131]

[0132] Optical platform where laser F is located

[0133] Phase output of each interferometer before weak light phase locking:

[0134]

[0135] The output phase of laser F after phase locking is as follows:

[0136]

[0137] in,

[0138]

[0139] After phase locking, the signal outputs of each interferometer on the optical platform where the laser F is located are as follows:

[0140]

[0141] Adopting the phase-locking scheme <PL-Seq3, master laser A>, a full-link phase-locking mechanism was constructed, as Figure 3 shown. In the figure, the optical platforms where Laser A, Laser B, Laser C, Laser D, Laser E, and Laser F are located are OB A, OB B, OB C, OB D, OB E, and OB F respectively. The entire detector has 18 interferometers and 18 interference signals in total. Each interference link is shown as Figure 4 shown, where SCI 1 and SCI 1s represent the interference links of two scientific interferometers between spacecraft S / C 2 and S / C3; SCI 2 and SCI 2s represent the interference links of two scientific interferometers between spacecraft S / C 1 and S / C 3; SCI 3 and SCI3s represent the interference links of two scientific interferometers between spacecraft S / C 1 and S / C 2; TM 1, TM 1s, REF 1, and REF 1s represent the interference links of 2 test mass interferometers and 2 reference interferometers between two optical platforms inside spacecraft S / C 1; similarly, TM 2, TM 2s, REF 2, and REF 2s represent the interference links of 2 test mass interferometers and 2 reference interferometers between two optical platforms inside spacecraft S / C 2; TM 3, TM 3s, REF 3, and REF 3s represent the interference links of 2 test mass interferometers and 2 reference interferometers between two optical platforms inside spacecraft S / C 3.

[0142] For the phase-locking scheme <PL-Seq3, master laser A>, the full-link phase-locking process is as follows:

[0143] (1) Left side: Laser A -> Laser B -> Laser C -> Laser D

[0144] Step 1: Laser A transmits the laser to OB B through an optical fiber and interferes with Laser B in the reference interferometer. After interference, Laser B is phase-locked to Laser A through a feedback control loop.

[0145] Step 2: The phase-locked Laser B is emitted to OB C through a telescope and interferes with Laser C in the scientific interferometer. After interference, Laser C is phase-locked to the received Laser B through a feedback control loop.

[0146] Step 3: The phase-locked Laser C is transmitted to OB D through an optical fiber and interferes with Laser D in the reference interferometer. After interference, Laser D is phase-locked to Laser C through a feedback control loop.

[0147] (2) Right side: Laser A -> Laser F -> Laser E

[0148] Step 1: Laser A is emitted onto OB F through a telescope and interferes with Laser F in the scientific interferometer. After interference, Laser F is phase-locked to Laser A through a feedback control loop.

[0149] Step 2: The phase-locked Laser F is transmitted to OB E through an optical fiber and interferes with Laser E in the reference interferometer. After interference, Laser E is phase-locked to Laser F through a feedback control loop.

[0150] Based on this model, a SIMULINK full-link simulation framework for the phase-locking scheme <PL-Seq3, master laser A> is established, which has the ability to simulate long-period detection signals including arbitrary wave sources and various noises, and analyzes the influence of the frequency planning scheme and planning results on the detection performance and scientific operation.

[0151] Adopting a static interference link, the sampling rate of the simulation system is 3 Hz, and a total of 79,200 seconds are simulated. To ensure the stability of the signal, the first 200 seconds of data are deleted, and only 79,000 data are used for subsequent analysis. The time-series interference signal outputs of the scientific interferometer, test mass interferometer, and reference interferometer are as Figure 5 、 Figure 6 and Figure 7 shown. There are 6 signals for each of the 3 types of interferometers in the full link, for a total of 18 signals.

[0152] Aiming at the problem of full-link simulation of a detection formation with a long period including a phase-locking mechanism for on-orbit motion characteristics that is difficult to achieve in ground experiments due to high detection accuracy, long period, and complex on-orbit environment, the present invention proposes a space-based gravitational wave detection signal simulation method and system including a phase-locking mechanism. Considering various noise coupling factors, 36 phase-locking schemes are set. Based on a specific phase-locking scheme, a full-link simulation signal model of a detection formation including a phase-locking mechanism is constructed.

[0153] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the embodiments, those of ordinary skill in the art should understand that any modification or equivalent replacement of the technical solutions of the present invention does not depart from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A space-based gravitational wave detection signal simulation system including a phase-locking mechanism, characterized in that: The system includes: a phase-locking mechanism signal simulation model, a phase-locking scheme design module and a detection formation full-link signal output module; wherein, The phase-locked mechanism signal simulation model includes three spacecraft simulation platforms with the same structure, two optical platforms are arranged on each spacecraft simulation platform, two measurement masses are arranged on each optical platform, and one scientific interferometer, one test mass interferometer and one reference interferometer are arranged; The phase-locking scheme design module is used to include 6 phase-locking sequence selections and 6 phase-locking main laser selections, forming a total of 36 phase-locking schemes; The detection formation full-link signal output module is used to select a phase-locking scheme according to the specified main laser, realize laser phase locking between different optical platforms of different spacecraft and realize phase output of each interferometer; The three spacecraft simulation platforms with the same structure are arranged in a counterclockwise direction, namely the first spacecraft, the second spacecraft and the third spacecraft simulation platform, the angle between the two optical platforms arranged on each spacecraft simulation platform is 60 degrees, and the six optical platforms form an equilateral triangle, lasers A and B are placed inside the two optical platforms of the first spacecraft simulation platform, and the masses TM1 and TM2 are measured, lasers C and D are placed inside the two optical platforms of the second spacecraft simulation platform, and the masses TM3 and TM4 are measured, lasers E and F are placed inside the two optical platforms of the third spacecraft simulation platform, and the masses TM5 and TM6 are measured, and each optical platform respectively transmits and receives lasers to two adjacent optical platforms; The six phase-locked sequences include: PL-Seq1, PL-Seq2, PL-Seq3, PL-Seq4, PL-Seq5 and PL-Seq6, wherein: Select Laser A as the main laser, PL-Seq1: Laser B is phase-locked to laser A received by the optical platform, laser C is phase-locked to laser B received by the optical platform, laser D is phase-locked to laser C received by the optical platform, laser E is phase-locked to laser D received by the optical platform, and laser F is phase-locked to laser E received by the optical platform; PL-Seq2: Laser B is phase-locked to laser A received by the optical platform, laser C is phase-locked to laser B received by the optical platform, laser D is phase-locked to laser C received by the optical platform, laser E is phase-locked to laser D received by the optical platform, and laser F is phase-locked to laser A received by the optical platform; PL-Seq3: Laser B is phase-locked to laser A received by the optical platform, laser C is phase-locked to laser B received by the optical platform, laser D is phase-locked to laser C received by the optical platform, laser E is phase-locked to laser F received by the optical platform, and laser F is phase-locked to laser A received by the optical platform; PL-Seq4: Laser B is phase-locked to laser A received by the optical platform, laser C is phase-locked to laser B received by the optical platform, laser D is phase-locked to laser E received by the optical platform, laser E is phase-locked to laser F received by the optical platform, and laser F is phase-locked to laser A received by the optical platform; PL-Seq5: Laser B is phase-locked to Laser A received by the optical platform where it is located. Laser C is phase-locked to Laser D received by the optical platform where it is located. Laser D is phase-locked to Laser E received by the optical platform where it is located. Laser E is phase-locked to Laser F received by the optical platform where it is located. Laser F is phase-locked to Laser A received by the optical platform where it is located. PL-Seq6: Laser B is phase-locked to Laser C received by the optical platform where it is located. Laser C is phase-locked to Laser D received by the optical platform where it is located. Laser D is phase-locked to Laser E received by the optical platform where it is located. Laser E is phase-locked to Laser F received by the optical platform where it is located. Laser F is phase-locked to Laser A received by the optical platform where it is located. The 36 phase-locking schemes include: <PL-Seq1, Master Laser A>, <PL-Seq2, Master Laser A>, <PL-Seq3, Master Laser A>, <PL-Seq4, Master Laser A>, <PL-Seq5, Master Laser A>, <PL-Seq6, Master Laser A>; <PL-Seq1, Master Laser B>, <PL-Seq2, Master Laser B>, <PL-Seq3, Master Laser B>, <PL-Seq4, Master Laser B>, <PL-Seq5, Master Laser B>, <PL-Seq6, Master Laser B>; <PL-Seq1, Master Laser C>, <PL-Seq2, Master Laser C>, <PL-Seq3, Master Laser C>, <PL-Seq4, Master Laser C>, <PL-Seq5, Master Laser C>, <PL-Seq6, Master Laser C>; <PL-Seq1, Master Laser D>, <PL-Seq2, Master Laser D>, <PL-Seq3, Master Laser D>, <PL-Seq4, Master Laser D>, <PL-Seq5, Master Laser D>, <PL-Seq6, Master Laser D>; <PL-Seq1, Master Laser E>, <PL-Seq2, Master Laser E>, <PL-Seq3, Master Laser E>, <PL-Seq4, Master Laser E>, <PL-Seq5, Master Laser E>, <PL-Seq6, Master Laser E>; <PL-Seq1, Master Laser F>, <PL-Seq2, Master Laser F>, <PL-Seq3, Master Laser F>, <PL-Seq4, Master Laser F>, <PL-Seq5, Master Laser F>, <PL-Seq6, Master Laser F>; The full-link signal output module of the detection formation selects the phase-locking scheme <PL-Seq3, Master Laser A> according to the specified Master Laser A, and respectively collects the phase signals output by each laser after phase-locking to satisfy the following formula: in, and Respectively represent the phase outputs of lasers B, C, D, E and F after phase locking; represents the laser frequency noise of laser A, Respectively represent the optical platform noise of the optical platform where lasers A, B, C, D, E, and F are located, and They represent the readout noise and other noise of the optical platform where laser B is located; and They represent the readout noise and other noise of the optical platform where the laser C is located; and They represent the readout noise and other noise of the optical platform where the laser D is located; and They represent the readout noise and other noise of the optical platform where the laser E is located; represents the readout noise of the optical platform where the laser F is located; φ GW12 (t) and φ GW13 (t) represent the laser phase changes caused by gravitational wave signals; and They represent the phase changes of laser C and laser F caused by the gravitational wave signal, represents the noise introduced by the phase-locking mechanism during the process of laser B being phase-locked to laser A, represents the noise introduced by the phase-locking mechanism when laser C is phase-locked to laser B, represents the noise introduced by the phase-locking mechanism when laser D is phase-locked to laser C. represents the noise introduced by the phase-locking mechanism during the process of laser E being phase-locked to laser F, It represents the noise introduced by the phase-locking mechanism when laser F is phase-locked to laser A.

2. The space-based gravitational wave detection signal simulation system with a phase-locking mechanism according to claim 1, characterized in that Among them, L -1 {·} represents the inverse Laplace transform, φ GW12 (s), φ GW13 (s) represents the frequency domain representation of the time-series gravitational wave signal.

3. The space-based gravitational wave detection signal simulation system including a phase-locking mechanism according to claim 2, characterized in that: The full-link phase-locking process of the phase-locking scheme <PL-Seq3, Master Laser A> includes: Left side: Step 1: Transmit Laser A to the second optical platform through an optical fiber, interfere with Laser B in the reference interferometer. After interference, make Laser B phase-locked to Laser A through a feedback control loop. Step 2: The phase-locked laser B is emitted onto the third optical platform to interfere with the laser C in the scientific interferometer. After the interference, the feedback control loop is used to make the laser C phase-locked with the received laser B. Step 3: The phase-locked laser C is transmitted to the fourth optical platform through an optical fiber, and interferes with the laser D in the reference interferometer. After the interference, the laser D is phase-locked to the laser C through a feedback control loop; Right side: Step 1: Laser A is launched onto the sixth optical platform and interferes with laser F in the scientific interferometer. After the interference, laser F is phase-locked to laser A through a feedback control loop; Step 2: The phase-locked laser F is transmitted to the fifth optical platform through an optical fiber, and interferes with the laser E in the reference interferometer. After the interference, the laser E is phase-locked to the laser F through a feedback control loop.

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