Microwave wireless energy transmission wave beam high-precision pointing and tracking method and system

Abstract

The invention discloses a microwave wireless energy transmission wave beam high-precision pointing and tracking method and system, and the system comprises an interferometer angle measurement module, an energy center self-adaptive detection module and a distance measurement and communication integrated feedback link module, and the interferometer angle measurement module provides an initial pointing angle for energy wave beam alignment. The charging satellite controls the transmitting antenna to transmit energy beams according to the angle measurement result of the interferometer. After a wave beam reaches a receiving antenna array surface, a receiving antenna measures power through a plurality of power monitoring points, then the actual position of an energy center is inverted through an adaptive measurement algorithm, the azimuth angle and the center offset distance of an incident wave beam under a receiving antenna coordinate system are obtained, and the pitch angle of an incident wave beam is estimated by combining distance measurement information. And the energy receiving satellite feeds back estimated values of the pitch angle and the azimuth angle to the transmitting antenna through the distance measurement and communication integrated feedback link to correct a beam pointing error, so that high-precision beam pointing control of the microwave energy transfer system is realized.

Description

Technical Field

[0001] The present invention relates to the field of high-precision beam pointing and tracking, and in particular to a method and system for high-precision microwave wireless energy transmission beam pointing and tracking involving a space power generation satellite and a power receiving satellite. Background Art

[0002] Currently, more than 95% of satellites in orbit are powered by solar arrays. The satellite platform is selected based on the power consumption of satellite instruments and equipment and the weight requirements of the payload, and then the size of the solar array is determined. However, with the increasing demand for the power supply capacity and life of the satellite platform, the traditional solar array power supply mode has problems such as the area and mass increasing with the increase of the power generation power of the solar sail panel, the complex deployment process is prone to failure, and the process of the solar array constantly adjusting the direction leads to a decrease in the stability of the entire satellite. Therefore, charging satellites through satellite wireless energy transmission has become an important research direction for the development of energy power and reliability of future space satellite platforms.

[0003] The beam pointing measurement and control method in the existing microwave energy transmission system is mainly based on the reverse beam control method of the directional backtracking array. This method mainly achieves accurate pointing measurement and control of the energy beam by adjusting the phase relationship between the guidance signal and the energy signal. This method has low accuracy and complex structure, and the accuracy of energy beam pointing directly affects the beam collection efficiency of the microwave wireless energy transmission system. The microwave energy transmission system not only requires high beam pointing accuracy and high energy collection efficiency, but also the structure is as simple as possible. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and to provide a method and system for high-precision pointing and tracking of microwave wireless energy transmission beams, which can improve the beam pointing accuracy and thus improve the energy collection efficiency of the microwave energy transmission system.

[0005] The object of the present invention is achieved through the following technical scheme: a microwave wireless energy transmission beam high-precision pointing and tracking method, wherein the power generation satellite transmits the energy beam through the transmitting antenna array, and the power receiving satellite receives it through the receiving antenna array, comprising the following steps:

[0006] S1. Before the energy beam is transmitted, the power generating satellite and the power receiving satellite firstly measure the angle using the interferometer angle measurement method. The measurement result is the pointing angle of the initial alignment of the energy beam. Then the initial alignment pointing angle is transmitted to the transmitting antenna through the integrated link. The transmitting antenna adjusts the array face to align with the receiving array face according to the measured angle and transmits the energy beam.

[0007] S2. Install power monitoring points on the receiving antenna array according to the set arrangement. After the energy beam reaches the receiving satellite receiving antenna array, the receiving array performs adaptive detection of the energy center according to the received power measured by the power monitoring point, and the actual position of the energy center is inverted through the power of the monitoring point;

[0008] S3. The receiving array obtains the azimuth angle and center offset distance of the incident beam in the receiving antenna coordinate system according to the energy center position detected by the power monitoring point, and then estimates the pitch angle of the incident beam in combination with the ranging information of the integrated link;

[0009] S4. The receiving satellite feeds back the estimated values ​​of the pitch angle and azimuth angle to the transmitting antenna through the integrated feedback link of ranging communication, corrects the beam pointing error, and thus realizes high-precision beam pointing control of the microwave energy transmission system.

[0010] A microwave wireless energy transmission beam high-precision pointing and tracking system, comprising: a power generation satellite, a transmitting antenna array, a power receiving satellite, a receiving antenna array, an interferometer angle measurement module, an energy center adaptive detection module, and a ranging communication integrated feedback link;

[0011] The power generation satellite is used to transmit energy beams through a transmitting antenna array;

[0012] The power receiving satellite is used to receive signals through a receiving antenna array;

[0013] The interferometer angle measurement module is used to measure the angles of the power generating satellite and the power receiving satellite before the energy beam is emitted, and the measurement results are used as the pointing angles for the initial alignment of the energy beam;

[0014] The energy center adaptive detection module is used to install power monitoring points on the receiving antenna array according to a set arrangement mode, and after the energy beam reaches the receiving satellite receiving antenna array, the energy center adaptive detection is performed according to the receiving power measured by the power monitoring points;

[0015] The integrated ranging communication feedback link is used to measure the distance between the power generating satellite and the power receiving satellite and to feed back the estimated values ​​of the pitch angle and azimuth angle to the transmitting antenna, so as to correct the beam pointing error and thus realize high-precision beam pointing control of the microwave energy transmission system.

[0016] The beneficial effect of the present invention is that the present invention can improve the beam pointing accuracy, thereby improving the energy collection efficiency of the microwave energy transmission system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The high-precision beam pointing and tracking method and system design diagram of the present invention;

[0018] Figure 2 It is a schematic diagram of the interferometer model of the present invention;

[0019] Figure 3 The integrated signal generation flow chart of the present invention;

[0020] Figure 4 This is a ranging pilot insertion diagram of the present invention;

[0021] Figure 5 It is a schematic diagram of the convolutional encoder principle of the present invention;

[0022] Figure 6 This is a block diagram of the OFDM modulation and demodulation principle of the present invention;

[0023] Figure 7 This is a diagram of the ranging pilot parallel tracking loop of the present invention. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following.

[0025] In the microwave wireless energy transmission system composed of power generation satellite and power receiving satellite, the power generation satellite and the power receiving satellite are respectively provided with microwave energy transmitting antenna and microwave energy receiving antenna. The functional modules of the microwave wireless energy transmission system include interferometer angle measurement and alignment, energy center adaptive detection and ranging communication integrated feedback link. The functional modules of the system include: interferometer angle measurement, energy center adaptive detection and ranging communication integrated feedback link. The overall design of the microwave wireless energy transmission beam pointing system is as follows: Figure 1 shown.

[0026] S1. Before the energy beam is launched, the power generating satellite and the power receiving satellite first use the interferometer angle measurement method to measure the angle. The measurement result is the pointing angle of the energy beam's initial alignment. Figure 2 .

[0027] The angle between the energy transmitting array of the power generating satellite and the energy receiving array of the power receiving satellite is measured by the interferometer angle measurement system. This angle is the initial pointing angle of the energy beam. The specific measurement process is:

[0028] S101. Assume that the interferometer angle measurement adopts a double-baseline interferometer angle measurement system, which includes two baselines of different lengths. The angle measurement formula is:

[0029]

[0030] Where d1 and d2 are the lengths of the two baselines, and d1<d2. N1 and N2 are the integer ambiguities in the carrier phase difference between the two baselines. The fractional part of the carrier phase difference between the two baselines entered as days respectively;

[0031] S102. Assume that the virtual length d0 = d2-d1 ≤ λ / 2, get

[0032]

[0033] According to the range of ξ2-ξ1, let

[0034]

[0035] Substitute the obtained ξ0 into the following angle formula to obtain the first ambiguity-free estimated arrival angle:

[0036]

[0037] S103. In order to obtain high-precision angle measurement values, and Substituting into the angle measurement formula, we get the first estimate of N1:

[0038]

[0039] Will Substitute the following formula to get

[0040]

[0041] S104. Add the two baselines to obtain the angle of arrival with M=N1+N2 times the accuracy at this time

[0042]

[0043] At this time, it is believed Cape Poda Measurement results.

[0044] After the measurement value is obtained, the initial alignment pointing angle is transmitted to the transmitting antenna through an integrated link. The transmitting antenna adjusts the array surface to align with the receiving array surface according to the measured angle and emits an energy beam.

[0045] S2. Install power monitoring points on the receiving antenna array in a certain arrangement. The power monitoring points can be evenly distributed or cross-distributed, such as Figure 2 , the phase center of the energy beam of the receiving array is obtained by surface reproduction. After the energy beam reaches the receiving satellite receiving antenna array, the receiving array performs energy center adaptive detection according to the receiving power measured at the power monitoring point, and the actual position of the energy center is inverted by the power of the monitoring point.

[0046] The step S2 comprises:

[0047] S201. Using an N×N rectangular power detection array to obtain the power density distribution of the energy signal on the receiving array, including:

[0048] The rectangular power detection array is a group of N×N antennas. The position of the array element (0,0) is the origin position O, and the coordinates are expressed as (0,0). 0,0 represents the incident beam received by the array element (0,0), S k,l Indicates that the coordinates of the array element are (x k ,y l ) received incident beam, P k,l Indicates that the coordinates of the array element are (x k ,y l ) received incident beam power, 0≤k≤N-1,0≤l≤N-1 and k and l are integers;

[0049] S k,l With S 0,0 The delay between It is expressed as:

[0050]

[0051] Among them, d x and d y They represent the spacing between adjacent antenna elements parallel to the x-axis and y-axis directions respectively. The spacing between adjacent antenna elements is equal, and d x =d y =d; then the coordinates of the array element are (x k ,y l ) The energy beam power received at the elevation angle and azimuth angle of θ and φ is expressed as:

[0052] P k,l (θ,φ)=g k (θ,φ)·exp{jωτ(θ,φ)}

[0053] =g k (θ,φ)exp{-j2πd(x k ·cosφ+y l ·sinφ)·sinθ / λ}

[0054] Where λ is the wavelength of the incident beam, g k (θ, φ) represents the complex amplitude of the energy beam received by the energy receiving antenna array with elevation angles θ and azimuth angles φ respectively;

[0055] When 0≤k≤N-1,0≤l≤N-1, for each combination of k and l, the calculated coordinates of the array element are (xk ,y l ) receives the energy beam power P with elevation and azimuth angles θ and φ respectively k,l (θ, φ), the power density distribution of the energy signal on the receiving array is the signal power received by each array element, expressed as a set:

[0056]

[0057] S202. Phase adjustment is performed on the obtained energy signal power density distribution to restore the power distribution when the energy center is aligned with the normal of the rectangular power detection array:

[0058] Assume that when the transmitter transmits an energy signal with an elevation angle of θ0 and an azimuth angle of φ0 to the receiving array, the received signal power is the largest. The receiver of θ0 and φ0 is known. Due to environmental reasons, the signal actually received by the receiving array is the elevation angle of θ0+Δ θ , the azimuth is φ0+Δ φ , Δ θ With Δ φ is an unknown quantity; it is necessary to find the phase adjustment weight when the received power is maximum, and then solve the pitch angle θ at this time through the phase adjustment weight i =θ0+Δ θ , azimuth φ i =φ0+Δ φ , using θ i ,φ i Solve the power distribution at this time. The specific process is:

[0059] The total power of the energy beam received by the energy receiving antenna array with elevation angles θ and azimuth angles φ respectively is expressed as:

[0060]

[0061] The phase adjustment weights w corresponding to different elevation angles and azimuth angles are k Substituting the incident signal, the expression is:

[0062]

[0063] In the formula,

[0064]

[0065] Among them, θ i and φ i are the corresponding elevation and azimuth angles under the phase adjustment weight;

[0066] Because θ i =θ0+Δ θ ,φ i =φ0+Δφ , taking θ0 and φ0 as initial values, and changing θ in steps of β within the range of [φ0-α, φ0+α] and [θ0-α, θ0+α] respectively. i and φ i The value of θ i and φ i Under this condition, the array receiving power z(θ i ,φ i ), compare different z(θ i ,φ i ), find z(θ i ,φ i ) is the largest, record the value of θ at this time i ,φ i , solve for the power P of all array elements k,l (θ i ,φ i ), abbreviated as P k,l , 0≤k≤N-1,0≤l≤N-1 and k and l are integers, that is, the power distribution when the energy center is aligned with the normal of the rectangular power detection array is obtained, which is recorded as:

[0067]

[0068] B-spline interpolation is performed on the power distribution after phase adjustment, and the B-spline surface is expressed as:

[0069]

[0070] Where S(u,v) is the approximation surface after B-spline interpolation, u and v are the domain parameters on the surface, m and n represent the discrete points in the domain of the approximation surface, and P k,l is a point on the surface, that is, the power P of the array element k,l (θ i ,φ i ), k and l represent the indexes on u and v respectively; N k,p (u) is the basis function of the B-spline interpolation acting in the u direction, N l,q (v) is the basis function of B-spline interpolation in the v direction, p and q are the orders of the basis function, p = q = 3, and are defined as follows:

[0071]

[0072] The power distribution after B-spline interpolation is a standard ellipse. The major and minor axes of the ellipse are measured, and the intersection of the two is the center of the ellipse, which is also the center of the energy beam.

[0073] S3. The receiving array obtains the azimuth angle and center offset distance of the incident beam in the receiving antenna coordinate system according to the energy center position detected by the power monitoring point, and then estimates the pitch angle of the incident beam in combination with the ranging information of the integrated link;

[0074] By inserting the ranging code into the OFDM pilot, the distance D between the receiving satellite and the generating satellite is measured. The center offset distance is obtained by the difference between the geometric center X of the receiving antenna array and the estimated value X' of the energy beam center, that is, d' = X-X'; the pitch angle is obtained by trigonometric function:

[0075]

[0076] Integrated signal design model such as Figure 3 , the design is as follows:

[0077] Different pseudo-random codes are inserted into the OFDM signal in the frequency domain as pilots. After receiving the OFDM signal through the channel, the receiver first converts the serial to parallel, removes the cyclic prefix, performs frequency offset estimation and compensation, and then performs FFT transformation. Finally, a series of parallel sub-signals are obtained after the transformation. The receiver will extract the sub-signal loaded with the pilot, and perform distance calculation while performing channel estimation.

[0078] The ranging pseudo code is used to replace the pilot. The inserted ranging code as a pilot can not only be used for channel estimation, but also can be used to measure the distance between the transmitting and receiving satellites, thus solving the problem that the traditional OFDM only uses the pilot for channel estimation and wastes the frequency band resources. Figure 4 The transmitter uses a comb pilot to insert the ranging pilot at a certain interval. At the same time, in order to quickly capture the ranging code, the ranging pilot uses different short-period ranging codes.

[0079] Before OFDM modulation, (2,1,7) convolutional code is used to encode information symbols to reduce the influence of channel factors such as fading and noise on the signal. The principle of convolutional code encoder is as follows: Figure 5 shown.

[0080] After the encoding is completed, the OFDM signal can be modulated and sent. The basic principle block diagram is as follows Figure 6 As shown, after the serial baseband transmission data is convolutionally encoded and QPSK modulated, it is converted from serial to parallel transmission data symbol streams, modulated on the subcarrier and sent out.

[0081] After receiving the OFDM signal, the channel is estimated, and then the signal is captured, tracked, and range-measured.

[0082] OFDM is a multi-carrier parallel transmission system. After inserting the pilot in the frequency domain, the signal of the kth pilot in the time domain is:

[0083]

[0084] Among them, P l [h] represents the lth pilot symbol on the hth subcarrier, l = 0, 1, 2, ..., ∞, h is the subcarrier position where the pilot is located, 0<h<N-1.

[0085] For the h-th pilot, the time domain continuous signal of the corresponding subchannel can be equivalent to:

[0086]

[0087] In the formula, p h (t) is the ranging subcode loaded on the hth subcarrier. After the receiver strips the subcarrier from the received ranging signal, it can obtain

[0088]

[0089] Among them, f d is the Doppler frequency shift produced by the signal during propagation. is the frequency deviation estimated by the receiver, τ is the delay of signal generation, is the delay compensated after synchronization at the receiving end. After frequency offset compensation and complete synchronization, that is, When , the above formula can be expressed as:

[0090]

[0091] According to the sampling frequency f s Sampling, f s ≥2 / T sym , the discrete form of the ranging pilot signal can be obtained as:

[0092]

[0093] Among them, i s is the phase sampling point of the ranging code corresponding to the time delay offset, and N(i) is the sampling signal corresponding to the noise. The correlation operation of the above formula is:

[0094]

[0095] In the formula, p h (ii k ) is the locally generated phase shift i k h-path ranging subcode, N h is the period of the hth ranging subcode. Cyclic adjustment i k You can get a peak value of R, at which point i k It is the approximate phase after the corresponding ranging code is offset.

[0096] In order to save resources, the receiver only serially captures each ranging signal, that is, captures each path signal in turn. The present invention adopts an equal sampling tracking loop based on a direct expansion baseband pseudo code DLL tracking loop. This loop has a higher tracking accuracy. Compared with the commonly used circuit implementation of the tracking loop, it eliminates the complex implementation of the loop digital oscillator and the influence of the uncertainty of the initial phase of the digital oscillator on the pseudo code tracking accuracy. The tracking loop structure is as follows Figure 7 As shown, the loop will track each ranging pilot in parallel. Each loop has the same DLL structure. It is the ranging pilot signal after the receiving end strips off the subcarriers. i is the serial number of the ranging pilot, indicating that there are i pilots for ranging. ID is the integral clearing. E is the leading correlation, and L is the lagging correlation, which respectively use the pseudo-random code that is one sampling point ahead or behind the current P branch pseudo code, that is:

[0097]

[0098] Where PL i (k) is the local pseudo-random code signal generated after capture. The phase detector of the loop uses the normalized dot product power phase detection algorithm, and the phase detector output error e(k) is:

[0099]

[0100] e(k) controls the local regenerated pseudo code generator to update a new set of pseudo code phase outputs PL i (a), a=k+1,k,k-1. The loop filter F(z) can make the local pseudo code phase transfer smoothly. This paper adopts an ideal second-order loop, and the digital filter function is:

[0101]

[0102] Among them, C1 and C2 are constant gains.

[0103] S4. The receiving satellite feeds back the estimated values ​​of the pitch angle and azimuth angle to the transmitting antenna through the integrated feedback link of ranging communication, corrects the beam pointing error, and thus realizes high-precision beam pointing control of the microwave energy transmission system.

[0104] Specifically, the estimated pitch angle θ' and the measured azimuth angle φ i Through the integrated link, θ' and φ are fed back to the power generation satellite. i As control amounts Δθ and Δφ, the control amounts Δθ and Δφ are added or subtracted from the original emission angle to adjust the emission array and correct the emission angle.

[0105] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the above embodiments, it is still possible for a person skilled in the art to modify the methods described in the above embodiments, such as changing the names of the methods, etc. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A microwave wireless energy transmission beam high-precision pointing and tracking method, wherein the power generation satellite transmits the energy beam through the transmitting antenna array, and the power receiving satellite receives it through the receiving antenna array, characterized in that: The following steps are involved: S1. Before the energy beam is transmitted, the power generating satellite and the power receiving satellite firstly measure the angle using the interferometer angle measurement method. The measurement result is the pointing angle of the initial alignment of the energy beam. Then the initial alignment pointing angle is transmitted to the transmitting antenna through the integrated link. The transmitting antenna adjusts the array face to align with the receiving array face according to the measured angle and transmits the energy beam. S2. Install power monitoring points on the receiving antenna array according to the set arrangement. After the energy beam reaches the receiving satellite receiving antenna array, the receiving array performs adaptive detection of the energy center according to the received power measured by the power monitoring point, and the actual position of the energy center is inverted through the power of the monitoring point; S3. The receiving array obtains the azimuth angle and center offset distance of the incident beam in the receiving antenna coordinate system according to the energy center position detected by the power monitoring point, and then estimates the pitch angle of the incident beam in combination with the ranging information of the integrated link; S4. The receiving satellite feeds back the estimated values ​​of the pitch angle and azimuth angle to the transmitting antenna through the integrated feedback link of ranging communication, corrects the beam pointing error, and thus realizes high-precision beam pointing control of the microwave energy transmission system.

2. A microwave wireless energy transmission beam high-precision pointing and tracking method according to claim 1, characterized in that: In step S1, the angle between the energy transmitting array of the power generating satellite and the energy receiving array of the power receiving satellite is measured by the interferometer angle measuring system. This angle is the pointing angle of the initial alignment of the energy beam. The specific measurement process is: S101. Assume that the interferometer angle measurement adopts a double-baseline interferometer angle measurement system, which includes two baselines of different lengths. The angle measurement formula is: Where d1 and d2 are the lengths of the two baselines, and d1<d2. N1 and N2 are the integer ambiguities in the carrier phase difference between the two baselines. The fractional part of the carrier phase difference between the two baselines entered as days respectively; S102. Assume that the virtual length d0 = d2-d1 ≤ λ / 2, get According to the range of ξ2-ξ1, let Substitute the obtained ξ0 into the following angle formula to obtain the first ambiguity-free estimated arrival angle: S103. In order to obtain high-precision angle measurement values, and Substituting into the angle measurement formula, we get the first estimate of N1: Will Substitute the following formula to get S104. Add the two baselines to obtain the angle of arrival with M=N1+N2 times the accuracy at this time At this time, it is believed Cape Poda Measurement results.

3. A microwave wireless energy transmission beam high-precision pointing and tracking method according to claim 1, characterized in that: The step S2 comprises: S201. Using an N×N rectangular power detection array to obtain the power density distribution of the energy signal on the receiving array, including: The rectangular power detection array is a group of N×N antennas. The position of the array element (0,0) is the origin position O, and the coordinates are expressed as (0,0). 0,0 represents the incident beam received by the array element (0,0), S k,l Indicates that the coordinates of the array element are (x k ,y l ) received incident beam, P k,l Indicates that the coordinates of the array element are (x k ,y l ) received incident beam power, 0≤k≤N-1,0≤l≤N-1 and k and l are integers; S k,l With S 0,0 The delay between It is expressed as: Among them, d x and d y They represent the spacing between adjacent antenna elements parallel to the x-axis and y-axis directions respectively. The spacing between adjacent antenna elements is equal, and d x =d y =d; then the coordinates of the array element are (x k ,y l ) The energy beam power received at the elevation angle and azimuth angle of θ and φ is expressed as: P k,l (θ,φ)=g k (θ,φ)·exp{jωτ(θ,φ)} =g k (θ,φ)exp{-j2πd(x k ·cosφ+y l ·sinφ)·sinθ / λ} Where λ is the wavelength of the incident beam, g k (θ, φ) represents the complex amplitude of the energy beam received by the energy receiving antenna array with elevation angles θ and azimuth angles φ respectively; When 0≤k≤N-1,0≤l≤N-1, for each combination of k and l, the calculated coordinates of the array element are (x k ,y l ) receives the energy beam power P with elevation and azimuth angles θ and φ respectively k,l (θ, φ), the power density distribution of the energy signal on the receiving array is the signal power received by each array element, expressed as a set: S202. Phase adjustment is performed on the obtained energy signal power density distribution to restore the power distribution when the energy center is aligned with the normal of the rectangular power detection array: Assume that when the transmitter transmits an energy signal with an elevation angle of θ0 and an azimuth angle of φ0 to the receiving array, the received signal power is the largest. The receiver of θ0 and φ0 is known. Due to environmental reasons, the signal actually received by the receiving array is the elevation angle of θ0+Δ θ , the azimuth is φ0+Δ φ , Δ θ With Δ φ is an unknown quantity; it is necessary to find the phase adjustment weight when the received power is maximum, and then solve the pitch angle θ at this time through the phase adjustment weight i =θ0+Δ θ , azimuth φ i =φ0+Δ φ , using θ i ,φ i Solve the power distribution at this time. The specific process is: The total power of the energy beam received by the energy receiving antenna array with elevation angles θ and azimuth angles φ respectively is expressed as: The phase adjustment weights w corresponding to different elevation angles and azimuth angles are k Substituting the incident signal, the expression is: In the formula, Among them, θ i and φ i are the corresponding elevation and azimuth angles under the phase adjustment weight; Because θ i =θ0+Δ θ ,φ i =φ0+Δ φ , taking θ0 and φ0 as initial values, and changing θ in steps of β within the range of [φ0-α, φ0+α] and [θ0-α, θ0+α] respectively. i and φ i The value of θ i and φ i Under this condition, the array receiving power z(θ i ,φ i ), compare different z(θ i ,φ i ), find z(θ i ,φ i ) is the largest, record the value of θ at this time i ,φ i , solve for the power P of all array elements k,l (θ i ,φ i ), abbreviated as P k,l , 0≤k≤N-1,0≤l≤N-1 and k and l are integers, that is, the power distribution when the energy center is aligned with the normal of the rectangular power detection array is obtained, which is recorded as: B-spline interpolation is performed on the power distribution after phase adjustment, and the B-spline surface is expressed as: Where S(u,v) is the approximation surface after B-spline interpolation, u and v are the domain parameters on the surface, m and n represent the discrete points in the domain of the approximation surface, and P k,l is a point on the surface, that is, the power P of the array element k,l (θ i ,φ i ), k and l represent the indexes on u and v respectively; N k,p (u) is the basis function of the B-spline interpolation acting in the u direction, N l,q (v) is the basis function of B-spline interpolation in the v direction, p and q are the orders of the basis function, p = q = 3, and are defined as follows: The power distribution after B-spline interpolation is a standard ellipse. The major and minor axes of the ellipse are measured, and the intersection of the two is the center of the ellipse, which is also the center of the energy beam.

4. A microwave wireless energy transmission beam high-precision pointing and tracking method according to claim 1, characterized in that: The step S3 comprises: By inserting the ranging code into the OFDM pilot, the distance D between the receiving satellite and the generating satellite is measured. The center offset distance is obtained by the difference between the geometric center X of the receiving antenna array and the estimated value X' of the energy beam center, that is, d' = X-X'; the pitch angle is obtained by trigonometric function:

5. A microwave wireless energy transmission beam high-precision pointing and tracking method according to claim 1, characterized in that: The step S4 comprises: The estimated pitch angle θ' and the measured azimuth angle φ i Through the integrated link, the θ' and φ are fed back to the power generation satellite. i As control amounts Δθ and Δφ, the control amounts Δθ and Δφ are added or subtracted from the original emission angle to adjust the emission array and correct the emission angle.

6. A microwave wireless energy transmission beam high-precision pointing and tracking system, using the method described in any one of claims 1 to 5, characterized in that: The system comprises: a power generation satellite, a transmitting antenna array, a power receiving satellite, a receiving antenna array, an interferometer angle measurement module, an energy center adaptive detection module, and a ranging communication integrated feedback link; The power generation satellite is used to transmit energy beams through a transmitting antenna array; The power receiving satellite is used to receive signals through a receiving antenna array; The interferometer angle measurement module is used to measure the angles of the power generating satellite and the power receiving satellite before the energy beam is emitted, and the measurement results are used as the pointing angles for the initial alignment of the energy beam; The energy center adaptive detection module is used to install power monitoring points on the receiving antenna array according to a set arrangement mode, and after the energy beam reaches the receiving satellite receiving antenna array, the energy center adaptive detection is performed according to the receiving power measured by the power monitoring points; The integrated ranging communication feedback link is used to measure the distance between the power generating satellite and the power receiving satellite and to feed back the estimated values ​​of the pitch angle and azimuth angle to the transmitting antenna, so as to correct the beam pointing error and thus realize high-precision beam pointing control of the microwave energy transmission system.

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