Multi-tone signal assisted distributed node broadband signal emission participated synthesis system and multi-tone signal assisted distributed node broadband signal emission participated synthesis method

Abstract

The invention discloses a multi-tone signal assisted distributed node broadband signal emission coherent synthesis system and method, and belongs to the technical field of antennae, and the method comprises the steps: firstly, N emission nodes maintain uplink signal frequency source synchronization, and emit modulation signals and multi-tone signals; then, a plurality of received single-tone signals are respectively extracted through down-conversion and low-pass filtering at a receiving node; secondly, estimating the phase difference and the time difference among the N transmitting nodes according to the decoupled multi-tone signal, and tracking and predicting the phase difference and the time difference through loop filtering; and finally, the time difference between the nodes is pre-compensated through time delay filtering at the transmitting node, and the phase difference between the nodes is pre-compensated at the same time, so that the maximization of the broadband signal transmitting participation synthetic gain is ensured. The method is suitable for broadband signal emission coherent synthesis under the condition of distributed high-dynamic nodes, the real-time performance is high, implementation is easy, and the gain and efficiency of broadband signal coherent synthesis can be improved.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and more specifically, to a distributed node broadband signal transmission coherent synthesis system and method assisted by multi-tone signals. Background Art

[0002] Distributed coherent systems are often used in many fields such as deep space telemetry and remote control, ultra-long-distance radar detection, and radio astronomy. Transmit beam coherence is achieved by coherently adjusting the transmitted signals of distributed nodes so that they can reach the receiving node simultaneously and in phase and focus the energy, thereby maximizing the gain of the node transmit coherent synthesis and achieving long-distance and high-precision communication, detection and tracking.

[0003] Existing distributed transmission coherent methods usually consider the coherent synthesis of narrowband signals, ignoring the inconsistency of signal envelope delay caused by the distance from the transmitting node to the receiving node; at the same time, it is assumed that the position of the distributed node is stationary. However, when considering the coherent synthesis of broadband signal transmission under high dynamic conditions of distributed nodes, the inconsistency of signal envelope delay caused by the distance from the transmitting node to the receiving node cannot be ignored; in addition, mobile nodes will cause the phase difference and delay variation between nodes to become real-time. The above two factors will make the traditional narrowband transmission coherent synthesis method no longer applicable. Therefore, finding a real-time and efficient time difference and phase difference estimation method suitable for highly dynamic nodes is crucial to improving the gain and efficiency of broadband signal transmission coherent synthesis. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and to provide a distributed node broadband signal transmission coherent synthesis system and method assisted by a multi-tone signal, which is suitable for the broadband signal transmission coherent synthesis in distributed high-dynamic node conditions, has high real-time performance and is easy to implement, and can improve the gain and efficiency of broadband signal coherent synthesis.

[0005] The object of the present invention is achieved through the following solutions:

[0006] A multi-tone signal assisted distributed node broadband signal transmission coherent synthesis system, comprising:

[0007] A high-dynamic distributed node broadband signal transmission model establishment module is used to enable N transmitting nodes to keep the uplink signal frequency source synchronized by enabling reset, and then transmit the uplink modulation signal and multi-tone signal through the T component;

[0008] The multi-tone signal extraction module captures the Doppler shift through the R component at the receiving node, and then extracts the received multiple single-tone signals respectively through down-conversion and low-pass filtering;

[0009] The parameter estimation module estimates the phase difference and time difference between any two transmitting nodes using the multiple single-tone signals decoupled by the multi-tone signal extraction module, and tracks and predicts the phase difference and time difference through loop filtering;

[0010] A parameter tracking and prediction module is used to track and predict the phase difference and time difference between any two transmitting nodes through loop filtering;

[0011] The performance evaluation module is used to pre-compensate the time difference between nodes through delay filtering at the transmitting node, and pre-compensate the phase difference between nodes, and then calculate the gain and efficiency of the coherent synthesis of broadband signal transmission at the receiving node.

[0012] Furthermore, the N transmitting nodes specifically include two transmitting nodes.

[0013] Further, the capturing of Doppler shift by using an R component at the receiving node specifically includes: capturing Doppler shift in real time by using an R component at the receiving node.

[0014] Furthermore, the tracking and predicting the phase difference and the time difference through loop filtering specifically includes: tracking and predicting the phase difference and the time difference in real time through loop filtering.

[0015] Furthermore, the tracking and predicting the phase difference and time difference between any two transmitting nodes through loop filtering specifically includes: tracking and predicting the phase difference and time difference between any two transmitting nodes in real time through loop filtering.

[0016] Further, the calculating the gain and efficiency of the wideband signal transmission coherent synthesis at the receiving node specifically includes: calculating the gain and efficiency of the wideband signal transmission coherent synthesis in real time at the receiving node.

[0017] A multi-tone signal assisted distributed node broadband signal transmission coherent synthesis method comprises the following steps:

[0018] First, N transmitting nodes keep the uplink signal frequency source synchronized and transmit the modulated signal and multi-tone signal;

[0019] Next, multiple received single tone signals are extracted respectively by down-conversion and low-pass filtering at the receiving node;

[0020] Then, the phase difference and time difference between N transmitting nodes are estimated based on the decoupled multi-tone signal, and tracked and predicted through loop filtering;

[0021] Finally, at the transmitting node, the time difference between nodes is pre-compensated by delay filtering, and the phase difference between nodes is pre-compensated at the same time to ensure the maximization of the coherent synthesis gain of broadband signal transmission.

[0022] Further, the N transmitting nodes keep the uplink signal frequency source synchronized, and transmit the modulated signal and the multi-tone signal, specifically including the sub-steps:

[0023] Step 1-1: The modulation signal and the positive and negative single tone signals transmitted from the nth node to the receiving node are represented as s n (t), s n1 (t), s n2 (t), its specific expression is:

[0024]

[0025] Where n = 1, ..., N, p(t) represents the broadband modulated signal transmitted by the node; f0 represents the frequency of the carrier signal of the same source of N transmitting nodes, f n Indicates the frequency of the positive / negative single tone signal emitted by the nth transmitting node; f v represents Doppler frequency shift; τ n ,θ n They represent the propagation delay and initial phase from the nth transmitting node to the receiving node respectively;

[0026] Step 1-2: Take the first transmitting node as the reference node, and the single tone frequency difference between the nth transmitting node and the first transmitting node is Δf n =f n -f1, the first node and the nth node transmit a positive single-tone signal to the receiving node respectively, represented by s n3 (t), s n4 (t), its specific expression is:

[0027]

[0028] Step 1-3: The specific expression of the received signal at the receiving node is:

[0029]

[0030] Step 1-4: If the first transmitting node is used as a reference, the phase difference between the nth transmitting node and the first transmitting node is:

[0031] ΔΦ n1 =2π(f0+f v )(τ n -τ1)+(θ n -θ1), n=2,…,N.

[0032] Further, the multiple single-tone signals received are extracted respectively by down-conversion and low-pass filtering at the receiving node, specifically including the sub-steps of: down-converting and low-pass filtering the multi-tone signals received at the receiving node in sequence, and decoupling the single-tone signals with zero frequency to obtain:

[0033]

[0034] Furthermore, the estimating the phase difference and time difference between N transmitting nodes according to the decoupled multi-tone signal specifically includes the following sub-steps:

[0035] Step 3-1: If the signal s n1 (t) and s n2 (t) and we get

[0036]

[0037] Step 3-2: Taking the first transmitting node as a reference, and Multiplying the conjugate of gives:

[0038]

[0039] Step 3-3: The estimated phase difference between the nth transmitting node and the first transmitting node is:

[0040] in, represents the phase to be solved;

[0041] Step 3-4: Transform the signal s n2 The conjugate of (t) and s n3 (t) and we get

[0042]

[0043] Step 3-5: Taking the first transmitting node as the reference, transmit the signal s 12 The conjugate of (t) and s n4 (t) and we get

[0044]

[0045] Step 3-6: and Multiplying them, we get:

[0046]

[0047] Step 3-7: The estimated time difference between the nth transmitting node and the first transmitting node is:

[0048]

[0049] Furthermore, the tracking and prediction by loop filtering specifically includes the following sub-steps:

[0050] Step 4-1: The loop filter tracks the phase difference between the nth transmitting node and the first transmitting node at the kth time:

[0051] δ Φ (k) = δ Φ (k-1)+b0x Φ (n)+b1x Φ (n-1);

[0052]

[0053] in, ζ is an empirical value, B L represents the noise bandwidth, T s is the update period of the loop filter; x Φ (k), δ Φ (k) They respectively represent the phase difference, loop filtering output result and phase difference prediction result at time k.

[0054] Step 4-2: The loop filter tracks the time difference between the nth transmitting node and the first transmitting node at the kth time as:

[0055] δ τ (k) = δ τ (k-1)+b0x τ (n)+b1x τ (n-1)

[0056]

[0057] Among them, x τ (k), δ τ (k) They respectively represent the phase difference, loop filtering output result and time difference prediction result at time k.

[0058] Furthermore, the method of pre-compensating the time difference between nodes by delay filtering at the transmitting node and pre-compensating the phase difference between nodes to ensure the maximization of the coherent synthesis gain of the broadband signal transmission specifically includes the following sub-steps:

[0059] Step 5-1: Estimation results of phase difference and time difference Feedback is given to the transmitting node, and the delay filter is used to compensate the time difference between the N-1 transmitting nodes and the first transmitting node. The specific expression is:

[0060]

[0061] Among them, h n(t) represents the continuous delay filter, f t represents the cutoff frequency in the continuous domain;

[0062] When processing in the discrete domain, the corresponding time delay filter is

[0063]

[0064] Among them, f n represents the normalized cutoff frequency in the discrete domain, f n =f t / f s , f s is the sampling rate; D represents the delay, N represents the order of the delay filter;

[0065] Step 5-2: After phase pre-compensation, the coherent synthesis signal at the receiving node C is

[0066]

[0067] Step 5-3: Calculate the gain and efficiency of the coherent synthesis of N transmitting nodes:

[0068]

[0069] The beneficial effects of the present invention include:

[0070] (1) The present invention can realize coherent synthesis of broadband signal transmission. The embodiment of the present invention provides a method for coherent synthesis of broadband signal transmission applicable to highly dynamic distributed nodes, which can simply and quickly estimate the phase difference and time difference between transmitting nodes simultaneously through multi-tone assistance;

[0071] (2) The present invention can achieve real-time tracking and prediction of parameters. The embodiment of the present invention provides a method for coherent synthesis of broadband signal transmission suitable for highly dynamic distributed nodes, which tracks and predicts the phase difference and time difference between transmitting nodes in real time through loop filtering; and pre-compensates the time difference between nodes in real time through delay filtering, while compensating the phase difference between nodes, to maximize the gain of broadband signal transmission coherent synthesis;

[0072] (3) The present invention has the characteristic of flexible system expansion. The embodiment of the present invention provides a multi-tone signal assisted distributed node broadband signal transmission coherent synthesis method, which can be expanded to a broadband signal coherent synthesis system with any number of transmitting nodes, and the easy-to-implement method ensures the stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0074] Figure 1 It is a structural principle block diagram of the system of an embodiment of the present invention;

[0075] Figure 2 Schematic diagram of the spatial geometry of the transmitting nodes A, B and the mobile receiving node C;

[0076] Figure 3 is the sum of the six-channel single-tone signals and the modulated signal received by node C;

[0077] Figure 4 Node C sequentially performs down-conversion and low-pass filtering on the six received single-tone signals;

[0078] Figure 5 Phase difference and time difference changes between transmitting nodes A and B predicted by loop filter tracking

[0079] Figure 6 A delay filter for compensating the time difference between transmitting nodes A and B;

[0080] Figure 7 The result of pre-compensating the time difference and phase difference of the modulated signal at the transmitting node B;

[0081] Figure 8 Performing down-conversion and low-pass filtering on the received coherent modulated signal for node C;

[0082] Fig. 9 The coherent synthesis gain changes are transmitted at node C based on the prediction parameter results of the loop filter tracking. DETAILED DESCRIPTION

[0083] All features disclosed in all embodiments in this specification, or steps in all methods or processes implicitly disclosed, except for mutually exclusive features and / or steps, can be combined and / or expanded or replaced in any manner.

[0084] In view of the current situation in the background, the following technical solutions are proposed to solve the problem that the traditional narrowband transmission coherent synthesis method cannot be applied to the estimation of broadband signal time difference and phase difference under the high dynamic conditions of distributed nodes:

[0085] In a preferred embodiment, a multi-tone signal-assisted distributed node broadband signal transmission coherent synthesis system is proposed, such as Figure 1As shown, the specific settings are:

[0086] A high-dynamic distributed node broadband signal transmission model establishment module is used to enable N transmitting nodes to keep the uplink signal frequency source synchronized by enabling reset, and then transmit the uplink modulation signal and multi-tone signal through the T component;

[0087] The multi-tone signal extraction module captures the Doppler shift through the R component at the receiving node, and then extracts the received multiple single-tone signals respectively through down-conversion and low-pass filtering;

[0088] The parameter estimation module estimates the phase difference and time difference between any two transmitting nodes using the multiple single-tone signals decoupled by the multi-tone signal extraction module, and tracks and predicts the phase difference and time difference through loop filtering;

[0089] A parameter tracking and prediction module is used to track and predict the phase difference and time difference between any two transmitting nodes through loop filtering;

[0090] The performance evaluation module is used to pre-compensate the time difference between nodes through delay filtering at the transmitting node, and pre-compensate the phase difference between nodes, and then calculate the gain and efficiency of the coherent synthesis of broadband signal transmission at the receiving node.

[0091] On the other hand, in a preferred embodiment, see Figure 2-Figure 9 The present invention provides a distributed node broadband signal transmission coherent synthesis method assisted by a multi-tone signal, performing the following steps:

[0092] Step 1: Establish a high-dynamic distributed node broadband signal transmission model. N transmitting nodes keep the uplink signal frequency source synchronized by enabling reset, and then transmit the uplink modulation signal and multi-tone signal through the T component;

[0093] Step 2: Establish a multi-tone signal extraction module, capture the Doppler shift in real time through the R component at the receiving node, and then extract the received multiple single-tone signals respectively through down-conversion and low-pass filtering;

[0094] Step 3: Establish a parameter estimation module. The parameter estimation module estimates the phase difference and time difference between any two transmitting nodes using multiple single-tone signals decoupled by the multi-tone signal extraction module, and tracks and predicts the phase difference and time difference in real time through loop filtering.

[0095] Step 4: Establish a parameter tracking and prediction module, which tracks and predicts the phase difference and time difference between any two transmitting nodes in real time through loop filtering;

[0096] Step 5: Establish a performance evaluation module. The performance evaluation module pre-compensates the time difference between nodes through delay filtering at the transmitting node, and pre-compensates the phase difference between nodes, and then calculates the gain and efficiency of the coherent synthesis of broadband signal transmission in real time at the receiving node.

[0097] In order to illustrate the distributed high-dynamic node broadband signal transmission coherent synthesis method, the specific processing steps are further described as follows:

[0098] Establish a high-dynamic distributed node broadband signal transmission model. Figure 2 , a spatial geometric diagram of two transmitting nodes and a single receiving node is given; assuming that the position coordinates of the transmitting node A are (1, 0, 0) m, the position coordinates of the transmitting node B are (1, 1, 4) m, the initial position of the receiving node C is (0, 0, 15) Km, and the receiving node C moves at a uniform speed of (0, 0.5, 1) Km / s, and the receiving node C moves within 0 to 12.45 s.

[0099] See also Figure 3 , six single-tone signals and modulation signals transmitted from transmitting node A and transmitting node B to receiving node C are given, where the single-tone signals are represented by s 11 (t), s 12 (t), s 21 (t), s 22 (t), s 23 (t), s 24 (t). The frequency of the homologous carrier signal is f0 = 2.2 GHz, and the bandwidth of the modulated signal p(t) transmitted by the transmitting nodes A and B is 10 MHz, and the signal sampling rate is f s =200MHz. The positive and negative single-tone signal frequencies of transmitting nodes A and B are f1 = 20MHz, f2 = 18MHz, Δf n =2MHz; transmitting nodes A and B send a positive tone signal respectively, with frequencies of 22MHz and 16MHz.

[0100] Establish a multi-tone signal extraction module. Figure 4 , gives the result of down-converting and low-pass filtering the four single-tone signals received at the receiving node C in sequence, and obtaining six zero-frequency receiving signals.

[0101] Establishing a parameter estimation module includes the following steps:

[0102] Step 3-1: Transform the signal s n1 (t) and s n2 (t) and we get

[0103]

[0104] Step 3-2: Taking the first transmitting node as a reference, and Multiplying the conjugate of gives:

[0105]

[0106] Step 3-3: The estimated phase difference between the nth transmitting node and the first transmitting node is:

[0107]

[0108] Step 3-4: Transform the signal s n2 The conjugate of (t) and s n3 (t) and we get

[0109]

[0110] Step 3-5: Taking the first transmitting node as the reference, transmit the signal s 12 The conjugate of (t) and s n4 (t) and we get

[0111]

[0112] Step 3-6: and Multiplying them, we get:

[0113]

[0114] Step 3-7: The estimated time difference between the nth transmitting node and the first transmitting node is:

[0115]

[0116] Build a parameter tracking prediction module. Figure 5 , gives the results of loop filter tracking and predicting time difference and phase difference, where the loop filter update period T s =50ms, ζ is 0.707, and the noise bandwidth is B L =10Hz,ω n =18.9rad / s.

[0117] Establish a performance evaluation module. The specific steps include:

[0118] See also Figure 6-Figure 7 , a delay filter used to pre-compensate the time difference between transmitting nodes A and B, and a delay filter for pre-compensating the time difference of the modulated signal at transmitting node B and phase difference Pre-compensation result, normalized cutoff frequency f of discrete domain delay filter n =0.4, D=-2.921, N=80.

[0119] See also Figure 8 , after down-converting and low-pass filtering the modulated signals transmitted by nodes A and B, the coherent synthesis result at the receiving node C is:

[0120]

[0121] See also Fig. 9 , according to the loop filter tracking prediction parameter results, the coherent synthesis gain change is transmitted at node C. It can be seen that the gain and efficiency of the coherent synthesis of the broadband signals transmitted by nodes A and B are:

[0122]

[0123] The specific implementation of the present invention is not limited to the above-mentioned methods. The above description is only the preferred embodiment of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein. It is possible for those skilled in the art to make various obvious changes, adjustments and substitutions without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may also include more other equivalent embodiments without departing from the principles and concepts of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A distributed node broadband signal transmission coherent synthesis system assisted by multi-tone signals, characterized in that: include: A high-dynamic distributed node broadband signal transmission model establishment module is used to enable N transmitting nodes to keep the uplink signal frequency source synchronized by enabling reset, and then transmit the uplink modulation signal and multi-tone signal through the T component; The multi-tone signal extraction module captures the Doppler shift through the R component at the receiving node, and then extracts the received multiple single-tone signals respectively through down-conversion and low-pass filtering; The parameter estimation module estimates the phase difference and time difference between any two transmitting nodes using the multiple single-tone signals decoupled by the multi-tone signal extraction module, and tracks and predicts the phase difference and time difference through loop filtering; A parameter tracking and prediction module is used to track and predict the phase difference and time difference between any two transmitting nodes through loop filtering; The performance evaluation module is used to pre-compensate the time difference between nodes through delay filtering at the transmitting node, and pre-compensate the phase difference between nodes, and then calculate the gain and efficiency of the coherent synthesis of broadband signal transmission at the receiving node.

2. The multi-tone signal-assisted distributed node broadband signal transmission coherent synthesis system according to claim 1, characterized in that: The N transmitting nodes specifically include two transmitting nodes.

3. The multi-tone signal-assisted distributed node broadband signal transmission coherent synthesis system according to claim 1, characterized in that: The capturing of Doppler shift by using the R component at the receiving node specifically includes: capturing the Doppler shift in real time by using the R component at the receiving node.

4. The multi-tone signal-assisted distributed node broadband signal transmission coherent synthesis system according to claim 1, characterized in that: The tracking and predicting the phase difference and the time difference through loop filtering specifically includes: tracking and predicting the phase difference and the time difference in real time through loop filtering.

5. The multi-tone signal-assisted distributed node broadband signal transmission coherent synthesis system according to claim 1, characterized in that: The tracking and predicting the phase difference and time difference between any two transmitting nodes by means of loop filtering specifically includes: tracking and predicting the phase difference and time difference between any two transmitting nodes in real time by means of loop filtering.

6. The multi-tone signal-assisted distributed node broadband signal transmission coherent synthesis system according to claim 1, characterized in that: The calculating the gain and efficiency of the wideband signal transmission coherent synthesis at the receiving node specifically includes: calculating the gain and efficiency of the wideband signal transmission coherent synthesis in real time at the receiving node.

7. A multi-tone signal-assisted distributed node broadband signal transmission coherent synthesis method, characterized in that: The steps include: First, N transmitting nodes keep the uplink signal frequency source synchronized and transmit the modulated signal and multi-tone signal; Next, multiple received single tone signals are extracted respectively by down-conversion and low-pass filtering at the receiving node; Then, the phase difference and time difference between N transmitting nodes are estimated based on the decoupled multi-tone signal, and tracked and predicted through loop filtering; Finally, at the transmitting node, the time difference between nodes is pre-compensated by delay filtering, and the phase difference between nodes is pre-compensated at the same time to ensure the maximization of the coherent synthesis gain of broadband signal transmission.

8. The multi-tone signal-assisted distributed node broadband signal transmission coherent synthesis method according to claim 7, characterized in that: The N transmitting nodes keep the uplink signal frequency source synchronized and transmit the modulated signal and the multi-tone signal, specifically including the sub-steps: Step 1-1: The modulation signal and the positive and negative single tone signals transmitted from the nth node to the receiving node are represented as s n (t), s n1 (t), s n2 (t), its specific expression is: Where n = 1, ..., N, p(t) represents the broadband modulated signal transmitted by the node; f0 represents the frequency of the carrier signal of the same source of N transmitting nodes, f n Indicates the frequency of the positive / negative single tone signal emitted by the nth transmitting node; f v represents the Doppler frequency shift; τ n ,θ n They represent the propagation delay and initial phase from the nth transmitting node to the receiving node respectively; Step 1-2: Take the first transmitting node as the reference node, and the single tone frequency difference between the nth transmitting node and the first transmitting node is Δf n =f n -f1, the first node and the nth node transmit a positive single-tone signal to the receiving node respectively, represented by s n3 (t), s n4 (t), its specific expression is: Step 1-3: The specific expression of the received signal at the receiving node is: Step 1-4: If the first transmitting node is used as a reference, the phase difference between the nth transmitting node and the first transmitting node is: DF n1 =2π(f0+f v )(t n -τ1)+(θ n -θ1),n=2,…,N.

9. The method for coherently synthesizing distributed node broadband signal transmission assisted by multi-tone signals according to claim 8, characterized in that: The method of extracting the received multiple single-tone signals respectively by down-conversion and low-pass filtering at the receiving node specifically includes the sub-steps of: sequentially down-converting and low-pass filtering the multi-tone signals received at the receiving node, and decoupling the zero-frequency single-tone signals respectively as follows:

10. The multi-tone signal-assisted distributed node broadband signal transmission coherent synthesis method according to claim 9, characterized in that: The method of estimating the phase difference and time difference between N transmitting nodes according to the decoupled multi-tone signal specifically includes the following sub-steps: Step 3-1: If the signal s n1 (t) and s n2 (t) and we get Step 3-2: Taking the first transmitting node as a reference, and Multiplying the conjugate of gives: Step 3-3: The estimated phase difference between the nth transmitting node and the first transmitting node is: Among them, ≮(·) means solving the phase; Step 3-4: Transform the signal s n2 The conjugate of (t) and s n3 (t) and we get Step 3-5: Taking the first transmitting node as the reference, transmit the signal s 12 The conjugate of (t) and s n4 (t) and we get Step 3-6: and Multiplying them, we get: Step 3-7: The estimated time difference between the nth transmitting node and the first transmitting node is:

11. The multi-tone signal-assisted distributed node broadband signal transmission coherent synthesis method according to claim 10, characterized in that: The tracking and prediction by loop filtering specifically includes the following sub-steps: Step 4-1: The loop filter tracks the phase difference between the nth transmitting node and the first transmitting node at the kth time: d Φ (k)=δ Φ (k-1)+b0x Φ (n)+b1x Φ (n-1); in, ζ is an empirical value, B L represents the noise bandwidth, T s is the update period of the loop filter; x Φ (k), δ Φ (k) They respectively represent the phase difference, loop filtering output result and phase difference prediction result at time k. Step 4-2: The loop filter tracks the time difference between the nth transmitting node and the first transmitting node at the kth time as: d τ (k)=δ τ (k-1)+b0x τ (n)+b1x τ (n-1) Among them, x τ (k), δ τ (k) They respectively represent the phase difference, loop filtering output result and time difference prediction result at time k.

12. The multi-tone signal-assisted distributed node broadband signal transmission coherent synthesis method according to claim 11, characterized in that: The method of pre-compensating the time difference between nodes by delay filtering at the transmitting node and pre-compensating the phase difference between nodes to ensure the maximization of the coherent synthesis gain of broadband signal transmission specifically includes the following sub-steps: Step 5-1: Estimation results of phase difference and time difference Feedback is given to the transmitting node, and the delay filter is used to compensate the time difference between the N-1 transmitting nodes and the first transmitting node. The specific expression is: Among them, h n (t) represents the continuous delay filter, f t represents the cutoff frequency in the continuous domain; When processing in the discrete domain, the corresponding time delay filter is Among them, f n represents the normalized cutoff frequency in the discrete domain, f n =f t / f s , f s is the sampling rate; D represents the delay, N represents the order of the delay filter; Step 5-2: After phase pre-compensation, the coherent synthesis signal at the receiving node C is: Step 5-3: Calculate the gain and efficiency of the coherent synthesis of N transmitting nodes:

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