A method and system for high-precision pointing and tracking of microwave wireless energy transfer beams

Abstract

The application discloses a kind of microwave wireless energy transmission beam high-precision pointing and tracking method and system, the system includes interferometer angle measurement, energy center adaptive detection and ranging communication integrated feedback link three modules, interferometer angle measurement module provides initial pointing angle for energy beam alignment, and charging satellite controls transmission antenna to emit energy beam according to interferometer angle measurement result.The power measured by multiple power monitoring points after beam reaches receiving antenna array, then the actual position of energy center is deduced by adaptive measurement algorithm, the azimuth angle of incident beam in the coordinate system of receiving antenna and the center offset distance are obtained, the elevation angle of incident beam is estimated in combination with ranging information, and the elevation angle and azimuth angle estimation value are fed back to transmission antenna by ranging communication integrated feedback link of energy-receiving satellite, and the pointing error of beam is corrected, so that the high-precision beam pointing control of microwave energy transmission system is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of high-precision pointing and tracking of beams, and particularly to a high-precision pointing and tracking method and system for microwave wireless energy transmission beams related to a space power generation satellite and a power receiving satellite. BACKGROUND

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

[0003] The beam pointing measurement and control method in the existing microwave energy transmission system is mainly a reverse beam control method based on a direction backtracking array. This method mainly adjusts the phase relationship between the guide signal and the energy signal to realize accurate pointing measurement and control of the energy beam. This method has low precision and complex structure, and the accuracy of the 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 requires a simple structure as much as possible. SUMMARY

[0004] The purpose of the present application is to overcome the shortcomings of the prior art and provide a high-precision pointing and tracking method and system for 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 purpose of the present application is achieved by the following technical solution: a high-precision pointing and tracking method for microwave wireless energy transmission beams, in which the power generation satellite transmits an energy beam through a transmitting antenna array, and the power receiving satellite receives the energy beam through a receiving antenna array, comprising the following steps:

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

[0007] S2. installing power monitoring points on the receiving antenna array in a set arrangement, after the energy beam reaches the receiving antenna array of the power receiving satellite, the receiving array performs energy center adaptive detection according to the received power measured by the power monitoring points, and the actual position of the energy center is obtained through power inversion of the monitoring points;

[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 points, and then estimates the elevation angle of the incident beam in combination with the ranging information of the integrated link;

[0009] S4. the power receiving satellite feeds back the elevation angle and azimuth angle estimation values to the transmitting antenna through the ranging communication integrated feedback link, 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 generating 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 generating satellite is used for transmitting an energy beam through the transmitting antenna array.

[0012] The power receiving satellite is used for signal receiving through the receiving antenna array.

[0013] The interferometer angle measurement module is used for angle measurement by the power generating satellite and the power receiving satellite before energy beam transmission, and the measurement result is used as the pointing angle of the initial alignment of the energy beam.

[0014] The energy center adaptive detection module is used for installing power monitoring points on the receiving antenna array in a set arrangement, and performing energy center adaptive detection according to the received power measured by the power monitoring points after the energy beam reaches the receiving antenna array of the power receiving satellite.

[0015] The ranging communication integrated feedback link is used for measuring the distance between the power generating satellite and the power receiving satellite and feeding back the elevation angle and azimuth angle estimation values to the transmitting antenna, correcting the beam pointing error, and thus realizing high-precision beam pointing control of the microwave energy transmission system.

[0016] The present application has the beneficial effects that: the present application can improve the beam pointing precision, and thus improve the energy collection efficiency of the microwave energy transmission system. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The beam high-precision pointing and tracking method and system are designed;

[0018] Figure 2 A schematic diagram of the interferometer model of the present application;

[0019] Figure 3 A flow chart of the integrated signal generation of the present application;

[0020] Figure 4 A diagram of the ranging pilot insertion of the present application;

[0021] Figure 5 A schematic diagram of the convolutional encoder principle of the present application;

[0022] Figure 6 A block diagram of the OFDM modulation principle of the present application;

[0023] Figure 7 A diagram of the ranging pilot parallel tracking loop of the present application. DETAILED DESCRIPTION

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

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

[0026] S1. Before the energy beam is transmitted, the power-generating satellite and the power-receiving satellite first measure the angle by using the interferometer angle measurement method, and the measurement result is the pointing angle of the initial alignment of the energy beam. The principle and model of the interferometer angle measurement are as shown in Figure 2 .

[0027] The angle between the energy transmitting array surface of the power-generating satellite and the energy receiving array surface of the power-receiving satellite is measured by the interferometer angle measurement system, and the angle is the pointing angle of the initial alignment of the energy beam The specific measurement process is as follows:

[0028] S101. Assuming that the interferometer angle measurement adopts a double-baseline interferometer angle measurement system, the system includes two baselines of different lengths, and the angle measurement formula is as follows:

[0029]

[0030] wherein λ is the wavelength of the incident beam, d1 and d2 are the lengths of the two baselines, and d1 < d2, N1 and N2 are the integer ambiguity in the carrier phase difference of the two baselines, the decimal part of the carrier phase difference of the two baselines input respectively as days;

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

[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 angle of arrival

[0036]

[0037] S103. In order to obtain high-precision angle measurement value, let and into the angle measurement formula to obtain the first estimated value of N1:

[0038]

[0039] Substitute into the following formula to obtain

[0040]

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

[0042]

[0043] At this time, it is considered that is the final angle of arrival measurement result.

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

[0045] S2. Install power monitoring points on the receiving antenna array surface according to a certain arrangement, which can be uniformly distributed and cross-distributed, such as Figure 2 , and obtain the phase center of the receiving array energy beam through surface reconstruction. After the energy beam reaches the receiving antenna array of the power receiving satellite, the receiving array detects the energy center adaptively according to the received power measured by the power monitoring point, and the actual position of the energy center is obtained through the power inversion of the monitoring point.​

[0046] The step S2 comprises:

[0047] S201. Obtain the power density distribution of the energy signal on the receiving array surface using an N×N rectangular power detection array, comprising:

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

[0049] The time delay between S k,l and S 0,0 is represented as:

[0050]

[0051] wherein d x and d y respectively represent the adjacent antenna element spacing in the x and y axis directions, the adjacent spacing between each antenna element is equal, and d x =d y =d; the incident beam power received by the array element with coordinates (x k ,y l ) at the elevation angle θ and the azimuth angle φ is represented 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] wherein 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 at the elevation angle θ and the azimuth angle φ; and ω represents the angular frequency of the incident beam.

[0055] ​The array element coordinates are calculated as (x k ,y l ) for each combination of k and l, where 0≤k≤N-1 and 0≤l≤N-1. k,l The power density distribution of the energy signal on the receiving array is the power received by each array element, expressed as a set:

[0056]

[0057] S202. The obtained power density distribution of the energy signal is phase-adjusted to restore the power distribution when the energy center is aligned with the normal of the rectangular power detection array:

[0058] Suppose the transmitting party transmits an energy signal with an elevation angle of θ0and an azimuth angle of φ0to the receiving array, the received signal power is maximum, θ0and φ0are known by the receiving party, due to environmental reasons, the actual received signal by the receiving array has an elevation angle of θ0+Δ θ and an azimuth angle of φ0+Δ φ , Δ θ and Δ φ are unknown; the phase adjustment weight when the received power is maximum needs to be found, and then the elevation angle θ i = θ0+ Δ θ and the azimuth angle φ i = φ0+ Δ φ at this time are solved, and θ i and φ i are used to solve the power distribution at this time, the specific process is as follows:

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

[0060]

[0061] The phase adjustment weight w k corresponding to different elevation angles and azimuth angles is substituted into the incident signal, and the expression is:

[0062]

[0063] In the formula,

[0064]

[0065] where θ i and φ i are the elevation angle and azimuth angle corresponding to the phase adjustment weight;

[0066] Because θi = θ0+ Δ θ , φ i = φ0+ Δ φ , θ i and φ i are changed in the range of [φ0- α, φ0+ α] and [θ0- α, θ0+ α] with β as the step, and the array receiving power z(θ i , φ i ) at each θ i and φ i is measured, different z(θ i , φ i ) are compared, the maximum z(θ i , φ i ) is found, θ i and φ i at this time are recorded, and the power P k,l (θ i , φ i ) of all array elements, simply recorded as P k,l , 0≤k≤N-1, 0≤l≤N-1 and k, l are integers, are solved, so that the power distribution when the energy center is aligned with the normal of the rectangular power detection array is obtained, recorded as:

[0067]

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

[0069]

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

[0071]

[0072] The power distribution after B-spline interpolation is a standard ellipse, the intersection of the long and short semi-axes of the ellipse 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 the 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 elevation angle of the incident beam in combination with the ranging information of the integrated link;

[0074] The ranging code is inserted into the OFDM pilot to measure the distance D between the power receiving satellite and the power generating satellite, and 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, i.e. d' = X-X'; the elevation angle is obtained by a trigonometric function:

[0075]

[0076] The integrated signal design model is as shown in Figure 3 , and is designed as follows:

[0077] Different pseudo-random codes are inserted into the OFDM signal as pilots from the frequency domain. After receiving the OFDM signal through the channel, the receiver first performs serial-parallel conversion, removes the cyclic prefix, performs frequency offset estimation and compensation, and then performs FFT conversion. Finally, the converted result is a series of parallel sub-signals, and the receiver will take out the sub-signals loaded with pilots to perform channel estimation and distance calculation at the same time.

[0078] The ranging pseudo-code is used to replace the pilot, and the inserted ranging code as the pilot can not only be used for channel estimation, but also can be used to measure the distance between the transmitting and receiving satellites, which solves the problem of wasting frequency band resources in the traditional OFDM which only uses pilots for channel estimation. The pilot insertion mode is as shown in Figure 4 The transmitter inserts the ranging pilot into the comb pilot at certain intervals, and at the same time, in order to realize fast capture of the ranging code, the ranging pilot uses different short period ranging codes.

[0079] Before OFDM modulation, the information symbols are encoded by a (2, 1, 7) convolution code to reduce the influence of channel factors such as fading and noise, and the principle of the convolution code encoder is as shown in Figure 5 .

[0080] After encoding, the OFDM signal can be modulated and transmitted, and the basic principle diagram is as shown in Figure 6 After convolution encoding and QPSK modulation, the serial baseband transmission data is converted into a parallel data symbol stream, and after modulating the sub-carrier, it is sent out.

[0081] After receiving the OFDM signal, the signal is channel estimated, then the signal is captured and tracked, and the ranging solution is solved.

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

[0085] For the hth pilot, the time domain continuous signal corresponding to the subchannel can be equivalent to:

[0086]

[0087] where p h (t) is the ranging subcode loaded on the hth subcarrier. The receiver can obtain

[0088]

[0089] where f d is the Doppler shift generated in the signal propagation process, is the frequency offset estimated by the receiver, τ is the time delay generated by the signal, is the time delay compensated by the receiver after synchronization. In the case of complete frequency offset compensation and synchronization, i.e. , the above formula can be expressed as:

[0090]

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

[0092]

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

[0094]

[0095] where p h (i-i k ) is the phase offset ik N is the hth ranging sub-code h is the period of the hth ranging sub-code k The peak value of R can be obtained when i k is the approximate phase after the ranging code offset.

[0096] In order to save resources, the receiver only serially acquires each ranging signal, i.e. acquires each sub-signal in turn. The present application adopts an equal sampling tracking loop based on a direct spread baseband pseudo code DLL tracking loop. This loop has high tracking accuracy, and compared with the circuit implementation commonly used in tracking loops, it eliminates the complex implementation of the loop digital oscillator and also eliminates the influence of the uncertainty of the initial phase of the digital oscillator on the pseudo code tracking accuracy. The tracking loop structure is shown in Figure 7 Each loop is the same DLL structure, is the ranging pilot signal after stripping the sub-carrier at the receiving end, i is the serial number of the ranging pilot, indicating that there are i ranging pilots, I-D is the integral clear. E is the early correlation and L is the late correlation, which use the pseudo random code of one sampling point in advance or in arrears of the current P branch pseudo code, i.e.

[0097]

[0098] In the formula, PL i (k) is the corresponding local pseudo random code signal generated after acquisition. The phase discriminator of the loop adopts the normalized dot product power phase discrimination algorithm, and the output error e(k) of the phase discriminator is:

[0099]

[0100] e(k) controls the local regenerative 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 smoothly shift. In this paper, an ideal second-order loop is adopted, and the digital filter function is:

[0101]

[0102] Wherein, C1, C2 are constant gains.

[0103] S4. The energy receiving satellite feeds back the pitch angle and azimuth angle estimation values to the transmitting antenna through the integrated feedback link of the 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 iThe θ' and φ are fed back to the power generation satellite through an integrated link i As the control quantity Δθ and φ, the control quantity Δθ and Δφ are added or subtracted on the basis of the original emission angle to adjust the emission array surface and correct the emission angle.

[0105] Finally, it should be noted that the above only for the preferred embodiments of the present application, and is not intended to limit the present application, although the foregoing embodiments of the present application has been described in detail, for those skilled in the art, it still can be modified to the method described in the foregoing embodiments, such as the change of the method name, etc. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application, should be included in the scope of protection of the present application.

Claims

1. A high-precision pointing and tracking method for microwave wireless power transmission beams, wherein a power-generating satellite transmits an energy beam through a transmitting antenna array, and a receiving satellite receives the beam through a receiving antenna array, characterized in that: The method comprises the following steps: S1. Before the energy beam is transmitted, the power-generating satellite and the power-receiving satellite first measure the angle by using an interferometer angle measurement method, and the measurement result is the pointing angle of the initial alignment of the energy beam; then the pointing angle of the initial alignment is transmitted to the transmitting antenna through an integrated link, the transmitting antenna adjusts the alignment of the array surface and the receiving array surface according to the measured angle, and transmits the energy beam; S2. The power monitoring points are installed on the receiving antenna array surface in a set arrangement mode, after the energy beam reaches the receiving antenna array surface of the power-receiving satellite, the receiving array surface detects the energy center adaptively according to the received power measured by the power monitoring points, and the actual position of the energy center is obtained through the power inversion of the monitoring points; S3. The receiving array surface obtains the azimuth angle and the center offset distance of the incident beam in the receiving antenna coordinate system according to the energy center position detected by the power monitoring points, and then estimates the elevation angle of the incident beam in combination with the ranging information of the integrated link; S4. The power-receiving satellite feeds back the elevation angle and the azimuth angle estimation value to the transmitting antenna through the ranging communication integrated feedback link, the pointing error of the beam is corrected, and thus the high-precision beam pointing control of the microwave energy transmission system is realized.

2. A method of high-precision pointing and tracking of a microwave wireless energy transfer beam according to claim 1, characterized in that: In the step S1, the angle between the energy transmitting array surface of the power-generating satellite and the energy receiving array surface of the power-receiving satellite is measured by using an interferometer angle measurement system, and the angle is the pointing angle θ of the initial alignment of the energy beam. The specific measurement process is as follows: S101. It is assumed that a double-baseline interferometer angle measurement system is used for the interferometer angle measurement, the system comprises two baselines with different lengths, and the angle measurement formula is as follows: where λ is the wavelength of the incident beam, d1 and d2 are the lengths of the two baselines respectively, and d1 < d2, N1 and N2 are the integer ambiguities in the carrier phase differences of the two baselines respectively, are the decimal parts of the carrier phase differences of the two baselines input respectively in days; S102. Assuming the virtual length d0=d2-d1< λ / 2, let resulting in According to the range of ξ2-ξ1, let Substitute the obtained into the following angle formula to obtain the first ambiguity-free estimated angle of arrival S103. In order to get high-precision angle measurement value, put and into the angle measurement formula, and get the first estimated value of N1: Bringing into the following equation gives S104. Add the two baselines to get M = N1+N2 times the accuracy of the bearing At this time At this time, it is considered that is the final θ measurement result.

3. A method of high-precision pointing and tracking of a microwave wireless energy transfer beam according to claim 1, characterized in that: The step S2 comprises: S201. The power density distribution of the energy signal on the receiving array surface is obtained by using an N×N rectangular power detection array, and the step comprises: A rectangular power detection array is a set of N x N antennas, the position of the array element (0, 0) is the origin position O, the coordinate is represented as (0, 0), S 0,0 represents the incident beam received by the array element (0, 0), S k,l represents the incident beam received by the array element with coordinates (x k ,y l ), P k,l represents the incident beam power received by the array element with coordinates (x k ,y l ), 0≤k≤N-1, 0≤l≤N-1 and k, l are integers; S k,l The time delay between S 0,0 The time delay between S is represented as: where d x and d y respectively represent the adjacent antenna element spacing in the x and y axis directions, the adjacent spacing between each antenna element is equal, and d x = d y = d; the element coordinates are (x k , y l ), and the energy beam power received with the elevation angle and azimuth angle being θ and φ respectively is represented 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) denotes the complex amplitude of the energy beam received by the energy receiving antenna array at an elevation angle and azimuth angle of θ,φ, respectively. The array element coordinates are calculated as (x k ,y l ) for each combination of k, l when 0≤k≤N-1, 0≤l≤N-1. k,l The power density distribution of the energy signal on the receiving array surface is the signal power received by each array element, expressed as a set: S202. The obtained power density distribution of the energy signal is phase-adjusted, and the power distribution when the energy center is aligned with the normal line of the rectangular power detection array is restored: Assume that the transmitting party transmits an energy signal with an elevation angle θ0 and an azimuth angle φ0 to the receiving array, the received signal power is maximum, θ0 and φ0 are known by the receiving party, due to environmental reasons, the actual signal received by the receiving array is an energy signal with an elevation angle θ0+Δ θ and an azimuth angle φ0+Δ φ , Δ θ and Δ φ are unknown quantities; it is necessary to find the phase adjustment weight when the received power is maximum, and then solve the elevation angle θ i = θ0+Δ θ and the azimuth angle φ i = φ0+Δ φ at this time, and use θ i and φ i to 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 surface with the elevation angle and the azimuth angle θ and φ is represented as follows: The phase adjustment weight w corresponding to different elevation angles and azimuth angles k Substituting the incident signal, the expression is: In the formula, where θ i and φ i are the phase-adjusted weights corresponding to the elevation and azimuth angles, respectively. Because θ i = θ0+ Δ θ , φ i = φ0+ Δ φ , the values of θ i and φ i are changed constantly with β as a step in the range of [φ0- α, φ0+ α] and [θ0- α, θ0+ α] respectively with θ0and φ0as initial values, and at each θ i and φ i , the array receiving power z(θ i , φ i ) at this time is measured, different z(θ i , φ i ) are compared, the maximum case of z(θ i , φ i ) is found, θ i , φ i at this time are recorded, and the power P k,l (θ i , φ i ) of all array elements is solved, which is simply recorded as P k,l , 0≤k≤N-1, 0≤l≤N-1 and k, l are integers, i.e. the power distribution situation when the energy center is aligned with the normal line of the rectangular power detection array is obtained, which is recorded as: The phase-adjusted power distribution is subjected to B-spline interpolation, and the B-spline surface is represented as follows: where S(u, v) is the approximated surface after B-spline interpolation, u and v are the parameters of the domain on the surface, m and n represent the discrete points in the domain of the approximated surface, P k,l is the point on the surface, that is, the power P k,l (θ i , φ i ) of the element, k and l represent the index in u and v respectively; N k,p (u) is the base function of B-spline interpolation acting in the u direction, N l,q (v) is the base function of B-spline interpolation acting in the v direction, p and q are the order of the base function, and p = q = 3 is taken, which is defined as follows: After the B-spline interpolation, the power distribution is a standard ellipse, and the intersection of the long semi-axis and the short semi-axis of the ellipse is the center of the ellipse, that is, the center of the energy beam.

4. The method of claim 1, wherein: the method further comprises: determining a direction of the microwave wireless energy transfer beam; and adjusting the direction of the microwave wireless energy transfer beam to a target direction. The step S3 comprises: The ranging code is inserted into the OFDM pilot, the distance D between the power-receiving satellite and the power-generating satellite is measured, the center offset distance is obtained by the difference between the geometric center X of the receiving antenna array surface and the estimation value X' of the energy beam center, that is, d'=X-X', and the elevation angle is obtained by a trigonometric function:

5. The method of claim 1, wherein: the method further comprises: determining a direction of the microwave wireless energy transfer beam; and adjusting the direction of the microwave wireless energy transfer beam to a target direction. The step S4 comprises: The estimated pitch angle θ' and the measured azimuth angle φ i The θ' and φ are fed back to the power generation satellite through an integrated link i As the control amounts Δθ and Δφ, the control amounts Δθ and Δφ are added to or subtracted from the original launch angle, the launch array is adjusted, and the launch angle is corrected.

6. A high-precision pointing and tracking system of microwave wireless energy transmission beams, using the method according to any one of claims 1 to 5, characterized in that, The system comprises a power-generating satellite, a transmitting antenna array surface, a power-receiving satellite, a receiving antenna array surface, an interferometer angle measurement module, an energy center adaptive detection module, and a ranging communication integrated feedback link. The power-generating satellite is used for transmitting an energy beam through the transmitting antenna array surface. The power-receiving satellite is used for receiving a signal through the receiving antenna array surface. The interferometer angle measurement module is configured to measure the angle between the power-generating satellite and the power-receiving satellite before the energy beam is transmitted, and the measurement result is used as the pointing angle of the initial alignment of the energy beam. The energy center adaptive detection module is configured to install power monitoring points on the receiving antenna array surface according to a set arrangement, and to perform adaptive detection on the energy center according to the received power measured by the power monitoring points after the energy beam reaches the receiving antenna array surface of the power-receiving satellite. The integrated ranging and communication feedback link is configured to measure the distance between the power-generating satellite and the power-receiving satellite, and to feed back the elevation angle and azimuth angle estimation values to the transmitting antenna, so as to correct the beam pointing error and achieve high-precision beam pointing control of the microwave energy transmission system.

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