CN109696673A

CN109696673A - Unstable aerial platform microwave stares relevance imaging earth observation method and system

Info

Publication number: CN109696673A
Application number: CN201910020488.7A
Authority: CN
Inventors: 郭圆月; 陈卫东; 邓杰; 蒋铮; 王东进; 袁博; 夏瑞
Original assignee: University of Science and Technology of China USTC
Current assignee: University of Science and Technology of China USTC
Priority date: 2019-01-09
Filing date: 2019-01-09
Publication date: 2019-04-30
Anticipated expiration: 2039-01-09
Also published as: CN109696673B

Abstract

The present invention provides a kind of unstable aerial platform microwave and stares relevance imaging earth observation method and system, include: to obtain aerial array in the position data and attitude data at each positioning moment, calculates aerial array in the average translational velocity and average velocity of rotation of each pulse period；And aerial array is thus obtained in each pulse period t_l,kThe instantaneous position vector sum attitude angle at moment；By each instantaneous position vector sum attitude angle, pulsed beam overlay area selection matrix is determined, determine aerial array in each period t_l,kThe random radiation field that moment is formed；Calculate t in each period_l,kMoment is scattered back wave field, and defines the amendment random radiation field for being scattered back wave field, to wave field is scattered back and random radiation field is associated processing, obtains ground observation region high-resolution imaging.Using method and system provided by the invention, the high-resolution imaging in ground observation region can be obtained in the case where random swing and vibrating state occur for aerial array.

Description

Unstable aerial platform microwave stares relevance imaging earth observation method and system

Technical field

The present invention relates to radar imaging technology field, in particular to a kind of unstable aerial platform microwave stares relevance imaging Earth observation method and system.

Background technique

Radar imagery (Radar Imaging) technology is a leap in radar development history, and it is initial to have expanded radar Detection and ranging function, enable radar using the electromagnetic scattering information obtained, obtain to the panoramic radar image of scene.

Microwave stares relevance imaging and surmounts the excellent of real aperture radar imaging resolution limit and fast imaging because having Point achieves faster development in recent years.In order to realize the lasting observation to the region of a certain emphasis, microwave stares association Imaging system is often using non-stable floating balloon etc. as radar carrier.Since floating balloon is influenced to make by factors such as wind-force Aerial array occur it is random swing and shake, cause in imaging process the position of aerial array, the posture of aerial array and The region of antenna array beam covering changes, so that the antenna array radiation field calculated under stationary state hypothesis and pulse Beam coverage area inaccuracy, and then influence image quality.

Summary of the invention

In view of this, the embodiment of the invention provides a kind of unstable aerial platform microwaves to stare relevance imaging earth observation Method, can aerial array occur it is random swing and vibrating state under, obtain aerial array different moments position data, Attitude data and pulsed beam overlay area eliminate influence of the unstable aerial platform random motion to imaging, thus To the high-resolution imaging in ground observation area.

To achieve the above object, the embodiment of the present invention provides the following technical solutions:

A kind of unstable aerial platform microwave stares relevance imaging earth observation method, comprising:

Aerial array is obtained in the position data and attitude data at each positioning moment, wherein the two neighboring positioning Time interval between moment is preset locating periodically, the aerial array using unstable aerial platform as carrier, and according to The preset pulse period, observation area emitted pulse signal, and real-time reception scattering corresponding with the pulse signal to the ground Echo；

According to the position data and attitude data, average translation of the aerial array in each pulse period is calculated Speed and average velocity of rotation；

According to the average translational velocity and average velocity of rotation, the aerial array is obtained in each pulse period Middle t_l,kThe instantaneous position vector sum attitude angle at moment；Wherein, the t_l,kMoment is preset in each pulse period adopts The sample moment；

According to t in each pulse period_l.kThe instantaneous position vector sum attitude angle at moment, the determining and antenna array Arrange the corresponding pulsed beam overlay area selection matrix of pulsed beam of the pulse signal of transmitting；

According to pulsed beam overlay area selection matrix, the pulse of the pulse signal of the aerial array transmitting is determined Wave beam t in each pulse period_l,kThe random radiation field that moment is formed；

According to the antenna array receiver to scatter echo calculate t in each pulse period_l,kThe scatter echo at moment , and the amendment random radiation field of the random radiation field is defined, wave field and the amendment random radiation field are scattered back to described It is associated processing, obtains the high-resolution imaging in the ground observation region.

The above method, it is optionally, described to calculate average speed of the aerial array within each pulse period and be averaged Velocity of rotation, comprising:

Determine target polynomial fit curve equation；

According to the target polynomial fit curve equation, determine the aerial array in the starting of each pulse period The position data and attitude data at quarter and the position data and attitude data of finish time；

Position data and attitude data and the day according to the aerial array in the initial time of each pulse period Linear array calculates the aerial array described each in the position data and attitude data of the finish time of each pulse period Average translational velocity and average velocity of rotation in pulse period.

The above method, optionally, the determining target polynomial fit curve equation, comprising:

Using preset polynomial fitting curve equation, to the aerial array obtained in each positioning The position data and attitude data at moment carry out curve fitting, the polynomial fitting curve equation are as follows:

Wherein,B, L and H is respectively longitude, latitude of the aerial array under geographic coordinate system Degree and height；θ,It is respectively pitch angle, azimuth and the roll angle of the aerial array with φ；a_ξ,kIt is polynomial fitting k times The coefficient of item；

The coefficient a of the polynomial fitting curve equation is solved according to least square method_ξ,k, wherein the coefficient a_ξ,k's Solve equation are as follows:

Wherein,For t_i,posThe position data and attitude data for the aerial array that moment positions, t_i,posFor I-th positions the moment；

The coefficient a obtained according to solution_ξ,k, determine the target polynomial fit curve equation.

The above method, it is optionally, described according to the average translational velocity and average velocity of rotation, obtain the antenna array It is listed in t in each pulse period_l,kMoment instantaneous position vector sum attitude angle, comprising:

By each transmitting antenna in the aerial array in any two neighboring positioning moment t_i,posAnd t_i+1,posBetween Each pulse period in t_l,kThe instantaneous position vector at momentIt indicates are as follows:

Wherein, n indicates n-th of transmitting antenna,For t_i,posThe position vector of n-th of transmitting antenna of moment is positioned,For in (t_l,k-t_i,pos) position vector variable quantity caused by the aerial array translation in time interval, For in (t_l,k-t_i,pos) position vector variable quantity caused by each transmitting antenna rotation in time interval；

By the receiving antenna in the aerial array in two neighboring positioning moment t_i,posAnd t_i+1,posBetween each institute State t in the pulse period_l,kThe instantaneous position vector at momentIt indicates are as follows:

Wherein,For t_i,posPosition the position vector of receiving antenna described in the moment；According to the aerial array in each institute State average translational velocity in the pulse period andEquation is solved, solution obtains

Wherein, describedSolution equation are as follows:

Wherein, t_i,posThe moment is positioned within the l' pulse period, t_i+1,posThe moment is positioned in l " a transmitting pulse is all In phase, the l pulse period is in the l' pulse period and the l " between a transmitting pulse period, i.e. l ' < l < l "；WithIt is respectively as follows: t in first of pulse period_l,kThe average translational velocity of aerial array described in moment, l' T in a pulse period_l,kThe average translational velocity of aerial array described in moment, t in the l'+1 pulse period_l,kDay described in moment T in -1 pulse period of the average translational velocity and l of linear array "_l,kThe average translational velocity of aerial array described in moment, T_P For the pulse period of the pulse signal；

According to average rotation speed of the aerial array within each pulse period, solution obtains the aerial array and exists T in each pulse period of the pulse signal_l,kThe attitude angle at moment；Wherein, the solution equation of the attitude angle are as follows:

Wherein,θ、Pitch angle, azimuth and the roll angle of the aerial array are respectively indicated with φ； ω_l′,α、ω_l'+1,α、WithIt is respectively as follows: t in the l' pulse period_l,kThe average rotation speed of aerial array described in moment T in degree, the l'+1 pulse period_l,kT in -1 pulse period of the average rotation speed of aerial array described in moment, l "_l,k The average rotation speed of n-th transmitting antenna and t in first of pulse period in aerial array described in moment_l,kAntenna described in moment The average rotation speed of n-th of transmitting antenna in array；

According to the attitude angle andEquation is solved, solution obtains

Wherein, describedSolve equation are as follows:

Wherein,For t_i,posThe antenna coordinate system O at moment_b-x_by_bz_bIt is transformed into geographic coordinate system O- The coordinate transformation matrix of xyz,For in the antenna coordinate system O_b-x_by_bz_bUnder, n-th of transmitting antenna in the aerial array Position vector；

It is obtained according to solutionWithDetermine the aerial array in the arteries and veins Rush t in each pulse period of signal_l,kThe instantaneous position vector sum attitude angle at moment.

The above method, optionally, the determination are corresponding with the pulsed beam for the pulse signal that the aerial array emits Pulsed beam overlay area selection matrix, comprising:

According to the aerial array in each pulse period of the pulse signal t_l,kThe instantaneous position vector sum at moment Attitude angle calculates t in each pulse period_l,kThe pulsed beam of pulse signal described in moment is formed by the pulsed beam area of coverage DomainCenter；

Based on the center, t in each pulse period is determined_l.kPulsed beam overlay area described in momentInstitute The distribution for stating ground observation area, to the region of each pulsed beam coveringUnion calculating is carried out, determines imaging observation area Domain S, wherein the region that the pulsed beam for the pulse signal that the imaging observation region S is emitted by the aerial array covers In the area of observation coverage that the ground observation region is formed；

The imaging observation region S is divided into M discretization grid, the M=P × Q, wherein P is orientation resolution Unit number, Q is distance to resolution cell number, and defines pulsed beam overlay area selection matrix are as follows:

Wherein, the l row of beam coverage area selection matrix D indicates t in first of pulse period_l,kAntenna array described in moment Arrange distribution of the pulsed beam of the pulse signal of transmitting in the imaging observation region S；

FoundationDetermine each element of the pulsed beam overlay area selection matrix D； Wherein, elementIndicate m-th of grid target of the imaging observation region S whether by t in first of pulse period_l,k The beam radiation field at moment radiates,For the center of each grid in the imaging observation area S, m=1,2......M；

According to by each element in the determining pulsed beam overlay area selection matrix D, really Fixed pulsed beam overlay area selection matrix D corresponding with the pulsed beam of pulse signal that the aerial array emits.

The above method, it is optionally, described according to pulsed beam overlay area selection matrix, obtain the aerial array The pulsed beam of the pulse signal of transmitting t in each pulse period_l.kThe random radiation field that moment is formed, comprising:

According to the pulsed beam overlay area selection matrix D and preset random radiation field computation formula, it is calculated Each pulse period t_l,kMoment, the net of the pulsed beam of the pulse signal of aerial array transmitting in the imaging observation area S Case is setPlace is formed by grid random radiation field；

The preset random radiation field computation formula are as follows:

Wherein, c=3 × 10⁸M/s, ForGrid position under momentRelative to the antenna array The phase centre location vector of n-th of transmitting antenna in columnDirection in space unit vector,Emit for described n-th The pattern function of antenna, s_n(t) pulse signal of n-th of transmitting antenna of t moment transmitting is indicated；

To the t in each pulse period_l.kThe pulsed beam of the pulse signal of the transmitting of aerial array described in moment is in institute State grid positionPlace is formed by grid random radiation field and sums, the formula of the summation are as follows:

Obtain the pulsed beam of the pulse signal of the aerial array transmitting t in each pulse period_l.kMoment shape At random radiation field.

The above method, optionally, the scatter echo arrived according to the antenna array receiver calculate each pulse period Middle t_l,kMoment is scattered back wave field, and defines the amendment random radiation field of the random radiation field, to it is described be scattered back wave field and The amendment random radiation field is associated processing, obtains the high-resolution imaging in the ground observation region, comprising:

According to scatter echo received by the receiving antenna in the aerial array, t in each pulse period is calculated_l.kWhen That carves is scattered back wave field, wherein scatter echo field computation formula are as follows:

Wherein, c=3 × 108m/s, ForGrid position under momentRelative to the antenna array Receiving antenna phase centre location vector in columnDirection in space unit vector,To receive day in the aerial array The pattern function of line,For grid positionThe scattering coefficient at place；

The pulsed beam of the pulse signal emitted by the aerial array t in each pulse period_l.kMoment formed with Machine radiation field defines t in each pulse period_l,kThe amendment random radiation field at moment are as follows:

And scatter echo field equation is indicated are as follows:

That is: E^sca=E^radσ, wherein σ is scattering coefficient matrix；

According to association process equation, wave field is scattered back and the amendment random radiation field is associated processing to described, is obtained To the high-resolution imaging in the ground observation region, wherein the association process equation are as follows:

Wherein,For the operator of relevance imaging algorithm.

A kind of unstable aerial platform microwave stares relevance imaging earth observation systems, comprising:

First acquisition unit, for obtaining aerial array in the position data and attitude data at each positioning moment；

Computing unit, for calculating the aerial array in each pulse week according to the position data and attitude data Interim average translational velocity and average velocity of rotation；

Second acquisition unit, for obtaining the aerial array according to the average translational velocity and average velocity of rotation The t in each pulse period_l,kThe instantaneous position vector sum attitude angle at moment；Wherein, the t_l,kMoment is each described Preset sampling instant in pulse period；

First determination unit, for according to t in each pulse period_l.kThe instantaneous position vector sum attitude angle at moment, Determine pulsed beam overlay area selection matrix corresponding with the pulsed beam of pulse signal that the aerial array emits；

Second determination unit, for determining the aerial array hair according to pulsed beam overlay area selection matrix The pulsed beam for the pulse signal penetrated t in each pulse period_l,kThe random radiation field that moment is formed；

Association process unit, for according to the antenna array receiver to scatter echo calculate in each pulse period t_l,kMoment is scattered back wave field, and defines the amendment random radiation field of the random radiation field, is scattered back wave field and institute to described It states amendment random radiation field and is associated processing, obtain the high-resolution imaging in the ground observation region；

Wherein, the first acquisition unit, computing unit, second acquisition unit, the first determination unit, the second determination unit High accuracy positioning is set to association process unit and determines appearance subsystem, and the high accuracy positioning determines appearance subsystem and is fixed on the day The array center of linear array；

Unstable aerial platform is suspended in aerial for the carrier as the aerial array；

Aerial array, for the transmitting of observation area to the ground pulse signal, simultaneously real-time reception is corresponding with the pulse signal Scatter echo.

Above system, optionally, the aerial array include multiple transmitting antennas and at least one receiving antenna.

Above system, optionally, further includes:

Self-adapting type can be changed suspension subsystem, for adjusting the opposite position of the aerial array Yu the ground observation region It sets.

The present invention provides a kind of unstable aerial platform microwaves to stare relevance imaging earth observation method, including obtains day Position data and attitude data of the linear array at each positioning moment, wherein the time interval at the two neighboring positioning moment For preset locating periodically, the aerial array is using unstable aerial platform as carrier, and transmitting pulse in observation area is believed to the ground Number and real-time reception scatter echo corresponding with the pulse signal；According to the position data and attitude data, institute is calculated Aerial array is stated in the average translational velocity and average velocity of rotation of each pulse period；According to the average translational velocity peace Equal velocity of rotation obtains the aerial array in each pulse period t of the pulse signal_l,kThe instantaneous position vector sum at moment Attitude angle；Wherein, t_l,kMoment is the sampling instant of preset each pulse period；According to each pulse period t_l.kMoment Instantaneous position vector sum attitude angle, determine that corresponding with the pulse signal wave beam that the aerial array emits pulsed beam is covered Cover area selection matrix；According to pulsed beam overlay area selection matrix, the pulse letter of the aerial array transmitting is determined Number in each pulse period t_l,kThe random radiation field that moment is formed；The scatter echo arrived according to the antenna array receiver calculates Each pulse period t_l,kMoment is scattered back wave field, and is associated place to wave field and the amendment random radiation field of being scattered back Reason, obtains the high-resolution imaging in the ground observation region.In aerial array random pendulum can occur for method provided by the invention Under dynamic and vibrating state, aerial array is obtained in the position data of different moments, attitude data and pulsed beam overlay area, Influence of the unstable aerial platform random motion to imaging is eliminated, to obtain the high-resolution imaging in ground observation area.

Detailed description of the invention

In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this The embodiment of invention for those of ordinary skill in the art without creative efforts, can also basis The attached drawing of offer obtains other attached drawings.

Fig. 1 is that a kind of unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method Method flow diagram；

Fig. 2 is that a kind of unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method Another method flow diagram；

Fig. 3 is that a kind of unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method Another method flow diagram；

Fig. 4 is that a kind of unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method Another method flow diagram；

Fig. 5 is object module image；

Fig. 6 is that target restores image when ignoring aerial array real time kinematics；

Fig. 7 is that a kind of unstable aerial platform microwave provided in an embodiment of the present invention is used to stare relevance imaging earth observation The resulting target of method restores image；

Fig. 8 is that a kind of unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation systems Schematic diagram.

Specific embodiment

Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other Embodiment shall fall within the protection scope of the present invention.

In this application, the terms "include", "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, So that the process, method, article or equipment for including a series of elements not only includes those elements, but also including not having The other element being expressly recited, or further include for elements inherent to such a process, method, article, or device.Do not having There is the element limited in the case where more limiting by sentence "including a ...", it is not excluded that in the mistake including the element There is also other identical elements in journey, method, article or equipment.

Unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method, method stream Journey figure is as shown in Figure 1, can specifically include:

S101: aerial array is obtained in the position data and attitude data at each positioning moment；

Method provided in an embodiment of the present invention, high accuracy positioning determine appearance subsystem according to preset locating periodically to non-steady Determining aerial platform is that carrier hangs the position data of skyborne aerial array and attitude data is acquired.With unstable aerial Platform is that the skyborne aerial array of carrier suspension can emit pulse described in pulse signal and real-time reception in observation area to the ground Generated scatter echo after object on signal and ground observation region interacts.

The high accuracy positioning determines the center that appearance subsystem is fixed on aerial array, dynamically obtains the position of aerial array Data and attitude data are set, longitude, latitude and the height (B including antenna array center under geographic coordinate system_t,L_t,H_t) and by Aerial array pitch angle, azimuth and the roll angle that the relative positional relationship of antenna coordinate system and geographic coordinate system determines

The geographic coordinate system and antenna coordinate system are defined as follows:

Geographical coordinate (north-west-day) is O-xyz: the first positioning moment t_1,pos, antenna array center is in ground observation area Domain is projected as coordinate origin, and X-axis is directed toward direct north, and Y-axis is directed toward due west direction, and Z axis faces upward perpendicular to ground；

Antenna coordinate system O_b-x_by_bz_b: origin is fixed on antenna array center, x_bAxis is identical as aerial array horizontal axis, z_bAxis Orthogonal array is directed toward imaging region, x_b-y_b-z_bConstitute right hand rectangular coordinate system.

Preferably, in method provided in an embodiment of the present invention, the pulse signal that aerial array is emitted is random frequency hopping letter Number:

Wherein, s_nIt (t) is the random signal of n-th of transmitter transmitting in aerial array, f_nlFor n-th of antenna radiation unit First of pulse tranmitting frequency, which randomly chooses in bandwidth range, and L is pulse number, and τ is the pulse duration, T_PFor the pulse period.

It should be noted that it is flat that unstable aerial platform can be floating balloon in method provided in an embodiment of the present invention The hanging utensil such as platform, dirigible, unstable aerial platform are fastened on the winch of ground by hawser, and flying height is controllable in an atmosphere.

S102: according to the position data and attitude data, it is flat in each pulse period to calculate the aerial array Equal translational velocity and average velocity of rotation；

Method provided in an embodiment of the present invention, according to according to preset locating periodically acquisition aerial array position data and Attitude data, can be calculated aerial array in the average translational velocity and average velocity of rotation of each pulse period, and first In pulse period, the translational velocity and rotational angular velocity of aerial array can be embodied as respectively:

Translational velocity vector, each element are respectively antenna array center O_bAlong O-xyz coordinate system 3 The velocity component of a reference axis, the translational velocity of each point is identical in aerial array；

Aerial array rotational angular velocity vector indicates antenna coordinate system O-xyz relative to geography Coordinate system O_b-x_by_bz_bAngle Position change rate.

In method provided in an embodiment of the present invention, the two neighboring positioning moment in that is, preset locating periodically, be may include Multiple pulse periods；

It should be noted that the movement of aerial array is broken down into translational motion in method provided in an embodiment of the present invention And rotational motion, and within each pulse period, the translational motion of aerial array and rotational motion are at the uniform velocity.

S103: according to the average translational velocity and average velocity of rotation, the aerial array is obtained in each arteries and veins Rush t in the period_l,kThe instantaneous position vector sum attitude angle at moment；

Method provided in an embodiment of the present invention, it is available according to the average translational velocity and average velocity of rotation acquired Aerial array t in each pulse period_l,kThe instantaneous position vector sum attitude angle at moment；Wherein t_l,kMoment is each arteries and veins Rush preset sampling instant in the period.

S104: according to t in each pulse period_l.kThe instantaneous position vector sum attitude angle at moment, the determining and day The corresponding pulsed beam overlay area selection matrix of pulsed beam of the pulse signal of linear array transmitting；

Method provided in an embodiment of the present invention, according to aerial array t in each pulse period_l.kThe instantaneous position at moment Vector sum attitude angle determines that pulsed beam overlay area corresponding with the pulse signal wave beam that aerial array is emitted selects square Battle array, to describe the pulsed beam for the pulse signal that different pulse period aerial arrays emit in each pulse period t_l,kThe variation of moment institute overlay area.

S105: according to pulsed beam overlay area selection matrix, the pulse signal of the aerial array transmitting is determined Pulsed beam in each pulse period t_l,kThe random radiation field that moment is formed；

Method provided in an embodiment of the present invention, according to described corresponding with the pulse signal wave beam that aerial array is emitted Pulsed beam overlay area selection matrix determines the pulsed beam of the pulse signal of aerial array transmitting in each pulse period t_l,kWhen be engraved on ground observation region formation random radiation field.

S106: according to the antenna array receiver to scatter echo calculate t in each pulse period_l,kThe scattering at moment Echo field, and the amendment random radiation field of the random radiation field is defined, wave field and the random spoke of amendment are scattered back to described It penetrates field and is associated processing, obtain the high-resolution imaging in the ground observation region.

Method provided in an embodiment of the present invention arrives corresponding with the pulse signal of transmitting scattered according to antenna array receiver It is emitted back towards wave, calculates t in each pulse period_l,kMoment is scattered back wave field, and is modified to random radiation field, is corrected Random radiation field, being scattered back wave field and correcting random radiation field for being calculated are associated processing, obtain ground observation area The high-resolution imaging in domain.

Unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method, comprising: obtains Take aerial array in the position data and attitude data at each positioning moment, wherein between the two neighboring positioning moment Time interval is preset locating periodically, and the aerial array is using unstable aerial platform as carrier, and according to preset pulse Period, observation area emitted pulse signal, and real-time reception scatter echo corresponding with the pulse signal to the ground；Foundation The position data and attitude data calculate average translational velocity of the aerial array in each pulse period and average turn Dynamic speed；According to the average translational velocity and average velocity of rotation, the aerial array is obtained in each pulse period Middle t_l,kThe instantaneous position vector sum attitude angle at moment；Wherein, the t_l,kMoment is preset in each pulse period adopts The sample moment；According to t in each pulse period_l.kThe instantaneous position vector sum attitude angle at moment, the determining and aerial array The corresponding pulsed beam overlay area selection matrix of the pulsed beam of the pulse signal of transmitting；It is covered according to the pulsed beam Regional choice matrix determines the pulsed beam of the pulse signal of the aerial array transmitting t in each pulse period_l,k The random radiation field that moment is formed；According to the antenna array receiver to scatter echo calculate t in each pulse period_l,kWhen That carves is scattered back wave field, and is associated processing to being scattered back wave field and correcting random radiation field, obtains ground observation region High-resolution imaging.

Relevance imaging earth observation method is stared using unstable aerial platform microwave provided in an embodiment of the present invention, it is comprehensive Aerial array caused by influencing because of factors such as wind-force is considered to swing and shake immediately, it is fixed in difference by obtaining aerial array The position data and attitude data at position moment calculate aerial array in each pulse week according to the position data and attitude data The average translational velocity and average velocity of rotation of phase；Then, day is calculated according to the average translational velocity and average velocity of rotation Linear array t in the pulse signal each pulse period_l,kThe instantaneous position vector sum attitude angle at moment, and according to the wink When position vector and attitude angle determine aerial array pulsed beam overlay area selection matrix, by the pulsed beam overlay area select It selects matrix and determines aerial array random radiation field, precisely determine the position of each moment aerial array, antenna array in imaging process The region of posture and the antenna array beam covering of column；Finally, scatter echo is calculated according to the scatter echo received , and it is associated processing to being scattered back wave field and correcting random radiation field, the high-resolution imaging in target observation region is obtained, It eliminates aerial array random swing occurs and shakes the adverse effect caused by imaging, ensure that image quality.

Unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method, the calculating Average translational velocity and average velocity of rotation of the aerial array within each period, as shown in Fig. 2, can specifically include:

S201: target polynomial fit curve equation is determined；

Method provided in an embodiment of the present invention, calculate average translational velocity within each period of the aerial array and When average rotation speed, it is first determined to the target polynomial fit curve equation calculated.

S202: according to the target polynomial fit curve equation, determine the aerial array in each pulse period The position data and attitude data of initial time and the position data and attitude data of finish time；

Method provided in an embodiment of the present invention determines aerial array according to the target polynomial fit curve equation determined In each pulse period initial time t_l,0Position data and attitude data and each finish time pulse period t_l,0+T_P Position data and attitude data.

S203: according to the aerial array the initial time of each pulse period position data and attitude data, and The aerial array calculates the aerial array in institute in the position data and attitude data of the finish time of each pulse period State the average translational velocity and average velocity of rotation in each pulse period.

Method provided in an embodiment of the present invention, according to the aerial array in the position of the initial time of each pulse period The position data and attitude data of data and attitude data and the aerial array in the finish time of each pulse period, meter Calculate average translational velocity and average velocity of rotation of the aerial array within each pulse period.

Method provided in an embodiment of the present invention, in first of pulse period, aerial array average rotation speed can be under Formula solves:

In first of pulse period, the aerial array translational velocity that is averaged can be solved by following formula:

Unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method, the calculating Average speed and average velocity of rotation of the aerial array within each pulse period, comprising: determine that target polynomial is fitted Curvilinear equation；According to the target polynomial fit curve equation, determine the aerial array in the starting of each pulse period The position data and attitude data at moment and the position data and attitude data of finish time；According to the aerial array each The position data and attitude data of the initial time of a pulse period and the aerial array each pulse period at the end of The position data and attitude data at quarter calculate average translational velocity peace of the aerial array within each pulse period Equal velocity of rotation.

Relevance imaging earth observation method is stared using unstable aerial platform microwave provided in an embodiment of the present invention, is determined Target polynomial fit curve equation, and according to the target polynomial fit curve equation, utilize the discrete day got Linear array obtains linear target polynomial fit curve equation in the position data and attitude data at each positioning moment, quasi- Aerial array really is described to occur to swing and shaken to aerial array position data and posture number at random due to by factors such as wind-force According to influence；And determine aerial array in the initial time of each pulse period by the target polynomial fit curve equation The position data and attitude data of position data and attitude data and finish time；Finally according to the aerial array each The finish time of the position data and attitude data of the initial time of pulse period and the aerial array in each pulse period Position data and attitude data, calculate average translational velocity of the aerial array within each pulse period and average Velocity of rotation, so that the average translational velocity being calculated and average velocity of rotation are more in line with aerial array and are putting at random Actual motion situation during dynamic and shaking.

Unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method, the determination Target polynomial fit curve equation, as shown in figure 3, can specifically include:

S301: preset polynomial fitting curve equation is used, to the aerial array obtained in each institute The position data and attitude data for stating the positioning moment carry out curve fitting；

Method provided in an embodiment of the present invention, the polynomial fitting curve equation are as follows:

Wherein,B, L and H be respectively longitude of the aerial array under geographic coordinate system, latitude and Highly；θ,It is respectively pitch angle, azimuth and the roll angle of the aerial array with φ；a_ξ,kFor k item of polynomial fitting Coefficient；

Preferably, method provided in an embodiment of the present invention, used polynomial fitting curve equation coefficient a_ξ,kIt is 3 times Term coefficient, i.e. K=3.

S302: the coefficient a of the polynomial fitting curve equation is solved according to least square method_ξ,k；

Method provided in an embodiment of the present invention is solved the coefficient a of polynomial fitting curve equation by least square method_ξ,k, make It obtains according to the calculated position data of polynomial fitting curve equation institute and attitude data that are determined by the coefficient and each positioning Moment position data collected and attitude data error reach minimum, to guarantee the accuracy of polynomial fitting curve equation.

The coefficient a_ξ,kSolution equation are as follows:

Wherein,For t_i,posThe position data and attitude data for the aerial array that moment positions, t_i,posFor I-th positions the moment.

S303: the coefficient a obtained according to solution_ξ,k, determine the target polynomial fit curve equation.

Providing method of the embodiment of the present invention, the coefficient a obtained according to solution_ξ,k, determine target polynomial fit curve equation Concrete form.It should be noted that be calculated according to the target polynomial fit curve equation by determination Position data and attitude data reach minimum with position data collected of each positioning moment and attitude data error.

Unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method, the determination Target polynomial fit curve equation includes: using preset polynomial fitting curve equation, to the day obtained Position data and attitude data of the linear array at each positioning moment carry out curve fitting；Then, according to least square method Solve the coefficient of the polynomial fitting curve equation；Finally, the coefficient a obtained according to solution_ξ,k, determine the target Polynomial fitting curve equation.

Relevance imaging earth observation method is stared using unstable aerial platform microwave provided in an embodiment of the present invention, is used Preset item formula fit curve equation, to the aerial array obtained in each position data and appearance for positioning the moment State data carry out curve fitting, and the coefficient a of polynomial fitting curve equation is solved according to least square method_ξ,k, and according to solution Obtained coefficient determines the polynomial fitting curve equation, so that the target polynomial fit curve equation is calculated Position data out and attitude data reach minimum with position data collected of each positioning moment and attitude data error, protect The accuracy of the target polynomial fit curve equation is demonstrate,proved.

Unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method, the foundation The average translational velocity and average velocity of rotation, obtain aerial array t in each pulse period_l,kWink at moment When position vector and attitude angle, can specifically include:

S401: according to average translational velocity of the aerial array within each pulse period and Equation is solved, solution obtains

Method provided in an embodiment of the present invention, in the antenna coordinate system O_b-x_by_bz_bUnder, the position of n-th of transmitting antenna Vector is denoted asReceiving antenna is located at antenna array center, and position vector is denoted as

In geographic coordinate system O-xyz, enables and position moment t in first pulse period_1,posWhen antenna array center position Setting vector isA positioning moment t of i-th (i=2,3 ... I)_i,pos, the position vector of receiving antenna It can be with approximate representation are as follows:

The position vector of n-th of transmitting antennaAre as follows:

Wherein,The t indicated for radian_i,posThe longitude and latitude for the aerial array that moment POS system measurement obtains Degree, R are the radius of the earth.For t_i,posThe antenna coordinate system O at moment_b-x_by_bz_bIt is transformed into geographical coordinate It is the coordinate transformation matrix of O-xyz, can be calculated by following formula

Method provided in an embodiment of the present invention, since high accuracy positioning determines appearance subsystem in arbitrarily two neighboring positioning Carve t_i,pos,t_i+1,posBetween comprising several transmitting pulse periods, t_i,posWithin the l' transmitting pulse period, and t_i+1,pos Positioned at l " in a transmitting pulse period, l (l'≤l < l "), then any time within l (l'≤l < l ") a pulse period t_l,k, n-th of position of transmitting antenna vectorIt can indicate are as follows:

Wherein,For t_i,posPosition the position vector of receiving antenna described in the moment；

According to average translational velocity of the aerial array within each pulse period andSolution side Journey, solution obtain

Wherein, describedSolution equation are as follows:

Wherein, t_i,posThe moment is positioned within the l' pulse period, t_i+1,posThe moment is positioned in l " a transmitting pulse is all In phase, the l pulse period is in the l' pulse period and the l " between a transmitting pulse period, i.e. l ' < l < l "；WithIt is respectively as follows: t in first of pulse period_l,kThe average translational velocity of aerial array described in moment, l' T in a pulse period_l,kThe average translational velocity of aerial array described in moment, t in the l'+1 pulse period_l,kDay described in moment T in -1 pulse period of the average translational velocity and l of linear array "_l,kThe average translational velocity of aerial array described in moment.

S402: according to average rotation speed of the aerial array within each pulse period, solution obtains the antenna Array t in each pulse period of the pulse signal_l,kThe attitude angle at moment；Wherein, the solution equation of the attitude angle Are as follows:

Wherein,θ、Pitch angle, azimuth and the roll angle of aerial array are respectively indicated with φ；ω_l',α、 ω_l'+1,α、WithIt is respectively as follows: t in the l' pulse period_l,kThe average rotation speed of moment aerial array, l'+1 T in pulse period_l,kT in -1 pulse period of the average rotation speed of aerial array described in moment, l "_l,kAntenna described in moment The average rotation speed of n-th transmitting antenna and t in first of pulse period in array_l,kN-th in aerial array described in moment The average rotation speed of transmitting antenna；

According to the attitude angle andSolution equation, solution obtains

Wherein,Solution equation are as follows:

According to position vector variable quantity caused by the aerial array translation that solution obtainsTransmitting antenna turns Position vector variable quantity caused by dynamicAnd attitude angleDetermine that the aerial array is believed in the pulse Number each pulse period in t_l,kThe instantaneous position vector sum attitude angle at moment.

Unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method, the foundation The average translational velocity and average velocity of rotation, obtain aerial array t in each pulse period_l,kWink at moment When position vector and attitude angle, comprising: according to average translational velocity of the aerial array within each pulse period and In (t_l,k-t_i,pos) position vector variable quantity caused by the aerial array translation in time intervalSolution equation, Solution obtainsAccording to average rotation speed of the aerial array within each pulse period, solution obtains the day Linear array t in each pulse period of the pulse signal_l,kThe attitude angle at moment；According to the attitude angle and in (t_l,k- t_i,pos) position vector variable quantity caused by each transmitting antenna rotation in time intervalSolution equation, ask Solution obtainsIt is obtained according to solutionWithDetermine that the aerial array exists T in each pulse period of the pulse signal_l,kThe instantaneous position vector sum attitude angle at moment.

It is acquired using method provided in an embodiment of the present invention according to the average translational velocity and average rotation speed Because occurred by aerial array it is random swing and wobble effects caused by instantaneous position vector variable quantity and attitude transformation amount, Aerial array t in each pulse period is obtained with this_l,kMoment instantaneous position vector sum attitude angle；So that gained Instantaneous position vector sum attitude angle it is more accurate, and then improve image quality.

Unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method, the determination Pulsed beam overlay area selection matrix corresponding with the pulsed beam of pulse signal of aerial array transmitting, such as Fig. 4 It is shown, it can specifically include:

S501: according to the aerial array in each pulse period of the pulse signal t_l,kThe instantaneous position at moment Vector sum attitude angle calculates t in each pulse period_l,kThe pulsed beam of pulse signal described in moment is formed by pulsed beam Overlay areaCenter；

Method provided in an embodiment of the present invention, in geographic coordinate system O-xyz, the antenna array beam of first of pulse covers Cover area is denoted asCoordinate of its center in xoy planeAre as follows:

Wherein,It is first of pulse period t respectively_l,kMoment antenna array center Position vector and aerial array attitude angle.

Method provided in an embodiment of the present invention, according to acquisition aerial array t in each pulse period_l,kMoment it is instantaneous Position vector and aerial array attitude angle, calculate t in each pulse period_l,kThe arteries and veins of the pulse signal of moment aerial array transmitting It rushes wave beam and is formed by pulsed beam overlay area in ground observation regionCenter.

It should be noted that aerial array t in each pulse period_l,kThe instantaneous position vector at moment includes day Linear array center, i.e. the receiving antenna t in each pulse period_l,kThe instantaneous position vector at moment；And each transmitting antenna exists T in each pulse period_l,kThe instantaneous position vector at moment.

S502: it is based on the center, determines t in each pulse period_l.kPulsed beam overlay area described in momentDistribution in the ground observation region, to the region of each pulsed beam coveringUnion calculating is carried out, is determined Imaging observation region S；

Method provided in an embodiment of the present invention presets the pulsed beam institute of the pulse signal of aerial array single emission The beam coverage area size of formation is w_x×w_y, w_x, w_yRespectively distance to orientation width.

Method provided in an embodiment of the present invention, based on t in each pulse period being calculated_l,kMoment aerial array hair The pulsed beam for the pulse signal penetrated is formed by pulsed beam overlay area in ground observation regionCenter, and According to preset single pulse beam coverage area w_x×w_ySize, determine t in each pulse period_l.kMoment institute State pulsed beam overlay areaDistribution in the ground observation region, and to the region of each pulsed beam coveringUnion calculating is carried out, determines imaging observation region S, wherein the imaging observation region S is the aerial array each T in pulse period_l,kThe region that the pulsed beam for the pulse signal that moment is emitted is covered is superimposed in the ground observation region The area of observation coverage of formation.

S503: the imaging observation region S is divided into M discretization grid, and defines the pulsed beam area of coverage Domain selection matrix；

Imaging observation region S is divided into M discretization grid by method provided in an embodiment of the present invention, and the M=P × Q, wherein P is orientation resolution cell number, and Q is distance to resolution cell number；And define the pulsed beam overlay area selection Matrix are as follows:

Wherein, the l row of beam coverage area selection matrix D indicates t in first of pulse period_l,kAntenna array described in moment Arrange distribution of the pulsed beam of the pulse signal of transmitting in the imaging observation region S.

S504: each element of the pulsed beam overlay area selection matrix D is determined；

Method provided in an embodiment of the present invention, foundationDetermine the pulsed beam covering Each element of regional choice matrix D；Wherein, elementIndicating m-th of grid target of the imaging observation region S is It is no by t in first of pulse period_l,kThe beam radiation field at moment radiates,For in each grid in the imaging observation area S Heart position, m=1,2......M.

S505: according to by each element in the determining pulsed beam overlay area selection matrix DDetermine pulsed beam overlay area choosing corresponding with the pulsed beam of pulse signal that the aerial array emits Select matrix D.

Method provided by the invention, according to by each in the determining pulsed beam overlay area selection matrix D Element, it may be determined that pulsed beam overlay area corresponding with the pulsed beam of pulse signal of aerial array transmitting selects Matrix D.

Unstable aerial platform microwave provided in an embodiment of the present invention stares relevance imaging earth observation method, the determination Pulsed beam overlay area selection matrix corresponding with the pulsed beam of pulse signal of aerial array transmitting, comprising: According to the aerial array in each pulse period of the pulse signal t_l,kThe instantaneous position vector sum attitude angle at moment, Calculate t in each pulse period_l,kThe pulsed beam of pulse signal described in moment is formed by pulsed beam overlay area's Center；Based on the center, t in each pulse period is determined_l.kPulsed beam overlay area described in moment? The distribution in the ground observation region, to the region of each pulsed beam coveringUnion calculating is carried out, determines that imaging is seen Survey region S；The imaging observation region S is divided into M discretization grid, and defines the pulsed beam overlay area selection Matrix；Determine each element of the pulsed beam overlay area selection matrix D；It is covered according to by the determining pulsed beam Each element in cover area selection matrix D, determination are corresponding with the pulsed beam of pulse signal that the aerial array emits Pulsed beam overlay area selection matrix D.

Relevance imaging earth observation method is stared using unstable aerial platform microwave provided in an embodiment of the present invention, is used Antenna beam coverage region selection matrix dynamically describes the arteries and veins of the pulse signal emitted in different pulse period aerial arrays It rushes wave beam and is formed by pulsed beam overlay area in the movement of entire observation area.

In method provided in an embodiment of the present invention, according to pulsed beam overlay area selection matrix, the day is obtained The pulse signal of linear array transmitting is in each pulse period t_l.kThe random radiation field that moment is formed, comprising:

According to the pulsed beam overlay area selection matrix D and preset random radiation field computation formula, it is calculated Each pulse period t_l,kMoment, grid position of the pulsed beam that the aerial array emits in the imaging area SPlace shape At random radiation field；

To in each pulse period t_l.kThe pulsed beam of the transmitting of aerial array described in moment is in the grid positionPlace The random radiation field of formation is summed, and obtains the pulse signal of the aerial array transmitting in each pulse period t_l.kMoment The random radiation field of formation.

Method provided in an embodiment of the present invention, pulsed beam overlay area selection matrix were described in the different pulse periods t_l.kMoment, aerial array transmitting pulsed beam imaging observation area movement, to obtain different pulse period random radiations The distribution of field.

Method provided in an embodiment of the present invention, the t of first of pulse period_l,kMoment, wherein l represents each pulse period In any one pulse period, the pulse signal of N number of transmitting antenna synchronized transmissions of aerial array is in the S of imaging observation regionPlace's superposition forms random radiation fieldIt may be expressed as:

Wherein,C=3 × 10⁸M/s, ForGrid position under momentPhase centre location vector relative to n-th of transmitting antenna in the aerial arrayDirection in space unit vector,For the pattern function of n-th of transmitting antenna, s_n(t) the pulse letter of n-th of transmitting antenna transmitting of t moment is indicated Number.

Method provided in an embodiment of the present invention, to each pulse period t_l.kThe impulse wave of the transmitting of aerial array described in moment Beam is in the grid positionPlace is formed by random radiation field and sums, the formula of the summation are as follows:

To obtain the pulse signal of the aerial array transmitting in each pulse period t_l.kThe random radiation that moment is formed ?.

In method provided in an embodiment of the present invention, calculated according to the scatter echo arrived according to the antenna array receiver each T in pulse period_l,kMoment is scattered back wave field, and defines the amendment random radiation field of the random radiation field, to the scattering Echo field and the amendment random radiation field are associated processing, obtain the high-resolution imaging in the ground observation region, comprising:

Method provided in an embodiment of the present invention, the transmitting antenna of aerial array is in the transmitting pulse signal of the area of observation coverage to the ground Meanwhile the reception line locking of aerial array receives the scatter echo in ground observation area.

Method provided in an embodiment of the present invention emits the t of pulse period at first_l,kMoment, receiving antenna receive entire The scatter echo in imaging observation area are as follows:

Wherein, ForGrid position under momentRelative to described The direction in space unit vector of receiving antenna phase centre location vector in aerial array,For the directional diagram of receiving antenna Function,For gridThe scattering coefficient at place.

By first of pulse period t_l,kMoment imaging observation area arbitrary mess vectorThe amendment random radiation field at place defines Are as follows:

Imaging equation is indicated are as follows:

That is: E^sca=E^radσ, wherein σ is scattering coefficient matrix.

It is obtained according to relevance imaging equation to wave field and the progress space time correlation imaging of amendment random radiation field is scattered back High-precision to ground observation area is imaged.Wherein, relevance imaging equation are as follows:

Wherein,For the operator of relevance imaging algorithm, once connection is imaged, can be associated with using direct single order field strength Algorithm, Pseudoinverse algorithm, orthogonal matching pursuit (OMP) algorithm, management loading (SBL) algorithm etc..

Below with reference to specific image scene, the principle of the present invention and effect are made by the drawings and specific embodiments detailed Description.Below by taking a more typical specific example as an example, a specific embodiment of the invention is provided, it still, should not be with this Limit practical application and protection scope of the invention.

Object module image is as shown in figure 5, emulation experiment setting aerial array caliber size is 1.5m × 1.5m, array element Number is 25, bandwidth 500MHz, carrier frequency 10GHz, and the transmitting signal pulse period is 5us, specific simulation parameter such as 1 institute of table Show:

System parameter	Parameter setting
		Radiant array caliber size D	1.5m×1.5m
Radiation source element number of array N	25
		The vertical range of imaging plane and radiant source plane	H₀=350m
Obliquely downward visual angle of the radiant source plane to imaging region	θ₀=45 °
		Two-dimensional imaging region area W_x×W_y	117m×117m
Simple beam overlay area area w_x×w_y	111m×111m
		Imaging region grid dividing number	39×39
Grid spacing ρ_a=ρ_r	3m
		Emit signal form	Random frequency hopping
Emit the signal pulse period	T_p=5us
		Pulse duration	τ=600ns
Signal frequency hopping bandwidth	B=500MHz
		Emit signal carrier frequency f₀	10GHz

Table 1

Ignore aerial array real time kinematics, that is, ignore unstable aerial platform by the factors such as wind-force influenced caused by with Machine swings and shakes, and directly will stare relevance imaging model applied under unstable aerial platform under static platform, target is extensive Complex pattern as shown in fig. 6, from fig. 6 it can be seen that at this time target restore picture quality it is very poor, do not see the wheel of target substantially It is wide.

High accuracy positioning is determined into the center that appearance subsystem is placed in aerial array, within the Polaroid time, when high-precision fixed When appearance subsystem record I=20 group data are determined in position, there are L/I=100 transmitting pulses between the two neighboring positioning moment.Fig. 7 Target to use the microwave relevance imaging method proposed by the present invention based on unstable aerial platform to obtain restores image.

Compare Fig. 6 and Fig. 7, it can be seen that the microwave of the unstable aerial platform proposed using this patent is associated to image space The target of method restores picture quality and is significantly improved.

Corresponding with the method for Fig. 1, it is solidifying that the embodiment of the invention provides a kind of microwaves of unstable aerial platform Depending on relevance imaging earth observation systems, for the specific implementation to method in Fig. 1.The microwave of the unstable aerial platform is stared Relevance imaging earth observation systems include: that unstable aerial platform, aerial array and high accuracy positioning determine appearance subsystem；Its In, the high accuracy positioning determines appearance subsystem as shown in figure 8, can specifically include:

First acquisition unit 801, for obtaining aerial array in the position data and attitude data at each positioning moment；

Computing unit 802, for calculating the aerial array in each pulse according to the position data and attitude data Average translational velocity and average velocity of rotation in period；

Second acquisition unit 803, for obtaining the antenna array according to the average translational velocity and average velocity of rotation It is listed in t in each pulse period_l,kThe instantaneous position vector sum attitude angle at moment；Wherein, the t_l,kMoment is each institute State preset sampling instant in the pulse period；

First determination unit 804, for according to t in each pulse period_l.kThe instantaneous position vector sum posture at moment Angle determines that pulsed beam overlay area corresponding with the pulsed beam of pulse signal that the aerial array emits selects square Battle array；

Second determination unit 805, for determining the aerial array according to pulsed beam overlay area selection matrix The pulsed beam of the pulse signal of transmitting t in each pulse period_l,kThe random radiation field that moment is formed；

Association process unit 806, for according to the antenna array receiver to scatter echo calculate in each pulse period t_l,kMoment is scattered back wave field, and defines the amendment random radiation field of the random radiation field, is scattered back wave field and institute to described It states amendment random radiation field and is associated processing, obtain the high-resolution imaging in the ground observation region；

Wherein, the first acquisition unit, computing unit, second acquisition unit, the first determination unit, the second determination unit High accuracy positioning is set to association process unit and determines appearance subsystem, wherein the high accuracy positioning is determined appearance subsystem and is fixed on The array center of the aerial array；

System provided in an embodiment of the present invention, including obtaining aerial array in the position data and posture at each positioning moment Data, wherein the time interval at the two neighboring positioning moment is preset locating periodically, and the aerial array is with unstable Aerial platform is carrier, to the ground observation area transmitting pulse signal and real-time reception scattering corresponding with the pulse signal Echo；According to the position data and attitude data, the aerial array is calculated in the average translational velocity of each pulse period With average velocity of rotation；According to the average translational velocity and average velocity of rotation, the aerial array is obtained in the pulse The each pulse period t of signal_l,kThe instantaneous position vector sum attitude angle at moment；Wherein, t_l,kMoment is preset each pulse week The sampling instant of phase；According to each pulse period t_l.kThe instantaneous position vector sum attitude angle at moment, the determining and antenna The corresponding pulsed beam overlay area selection matrix of the pulse signal wave beam of array emitter；According to the pulsed beam area of coverage Domain selection matrix determines the pulse signal of the aerial array transmitting in each pulse period t_l,kThe random radiation that moment is formed ?；The scatter echo arrived according to the antenna array receiver calculates each pulse period t_l,kMoment is scattered back wave field, and to scattered It is emitted back towards wave field and amendment random radiation field is associated processing, obtain the high-resolution imaging in ground observation region.The present invention provides System, can aerial array occur it is random swing and vibrating state under, obtain aerial array in the positional number of different moments According to, attitude data and pulsed beam overlay area, influence of the unstable aerial platform random motion to imaging is eliminated, thus Obtain the high-resolution imaging in ground observation area.

System provided in an embodiment of the present invention, the aerial array includes multiple transmitting antennas and at least one receives day Line, transmitting antenna are used for the synchronous transmission pulse signal of the ground area of observation coverage, and receiving antenna is for receiving and the pulse signal pair The scatter echo answered.Wherein, transmitting antenna can uniformly or non-uniform Distribution forms aerial array, and receiving antenna is located at antenna array At the center of column.

System provided in an embodiment of the present invention, further includes: self-adapting type can be changed suspension subsystem, for adjusting the antenna The relative position of array and the ground observation area.

System provided in an embodiment of the present invention calculates the aerial array according to the position data and attitude data During average translational velocity in each pulse period and average velocity of rotation, the computing unit 802 be can wrap It includes:

First determines subelement, for determining target polynomial fit curve equation；

Second determines subelement, for determining that the aerial array exists according to the target polynomial fit curve equation The position data and attitude data of the initial time of each pulse period and the position data and attitude data of finish time；

Computation subunit, for according to the aerial array the initial time of each pulse period position data and appearance State data and the aerial array calculate the day in the position data and attitude data of the finish time of each pulse period Average translational velocity and average velocity of rotation of the linear array within each pulse period.

The system that inventive embodiments provide, during determining target polynomial fit curve equation, described first really Stator unit, comprising:

Subelement is obtained, for using preset polynomial fitting curve equation, to the antenna array obtained The position data and attitude data for being listed in each positioning moment carry out curve fitting；

The polynomial fitting curve equation are as follows:

Wherein,a_{ξ, k}For the coefficient of k item of polynomial fitting；

Subelement is solved, for solving the coefficient a of the polynomial fitting curve equation according to least square method_ξ,k, In, the coefficient a_ξ,kSolution equation are as follows:

Determine subelement, the coefficient a for obtaining according to solution_ξ,k, determine the target polynomial matched curve side Journey.

System provided in an embodiment of the present invention, according to the average translational velocity and average velocity of rotation, described in acquisition Aerial array t in each pulse period_l,kDuring moment instantaneous position vector sum attitude angle, described second is obtained Unit 803 may include:

First solves subelement, for the average translational velocity according to the aerial array within each pulse period AndEquation is solved, solution obtains

Wherein, describedSolution equation are as follows:

Second solution subelement is asked for the average rotation speed according to the aerial array within each pulse period Solution obtains aerial array t in each pulse period of the pulse signal_l,kThe attitude angle at moment；Wherein, the posture The solution equation at angle are as follows:

Wherein,θ、Pitch angle, azimuth and the roll angle of the aerial array are respectively indicated with φ；

Third solves subelement, for according to the attitude angle andEquation is solved, solution obtains

Wherein, describedSolve equation are as follows:

Wherein,For t_i,posThe antenna coordinate system O at moment_b-x_by_bz_bIt is transformed into geographic coordinate system O- The coordinate transformation matrix of xyz,For in antenna coordinate system O_b-x_by_bz_bUnder, the position of n-th of transmitting antenna in the aerial array Set vector；

4th solves subelement, for what is obtained according to solutionWithDetermine institute State aerial array t in each pulse period of the pulse signal_l,kThe instantaneous position vector sum attitude angle at moment.

System provided in an embodiment of the present invention, in the pulsed beam phase for determining the pulse signal emitted with the aerial array During the selection matrix of corresponding pulsed beam overlay area, first determination unit 804 may include:

First computation subunit, for according to the aerial array in each pulse period of the pulse signal t_l,k The instantaneous position vector sum attitude angle at moment, calculates t in each pulse period_l,kThe pulsed beam institute of pulse signal described in moment The pulsed beam overlay area of formationCenter；

Second computation subunit determines t in each pulse period for being based on the center_l.kPulse described in moment Beam coverage areaDistribution in the ground observation area, to the region of each pulsed beam coveringCarry out union It calculates, determines imaging observation region S, wherein the imaging observation region S is the arteries and veins of the pulse signal of aerial array transmitting Rush the area of observation coverage that the region that wave beam is covered is formed in the ground observation region；

Discrete subelement, for the imaging observation region S to be divided into M discretization grid, the M=P × Q, In, P is orientation resolution cell number, and Q is distance to resolution cell number, and defines pulsed beam overlay area selection matrix Are as follows:

Element determines subelement, is used for foundationDetermine the pulsed beam overlay area Each element of selection matrix D；Wherein, elementIndicate the imaging observation region S m-th of grid target whether By t in first of pulse period_l,kThe beam radiation field at moment radiates；

Matrix determines subelement, for according to by each in the determining pulsed beam overlay area selection matrix D A element determines pulsed beam overlay area selection corresponding with the pulsed beam of pulse signal that the aerial array emits Matrix D.

System provided in an embodiment of the present invention is determining the pulsed beam of the pulse signal of the aerial array transmitting each T in a pulse period_l,kDuring the random radiation field that moment is formed, second determination unit 805 may include:

Computation of radiation field subelement, for according to the pulsed beam overlay area selection matrix D and preset random spoke Field computation formula is penetrated, is calculated in each pulse period t_l,kMoment, the pulsed beam of the pulse signal of the aerial array transmitting In the grid position of the imaging observation area SPlace is formed by grid random radiation field, whereinFor the imaging observation area The center of each grid, m=1,2......M in S；

The preset random radiation field computation formula are as follows:

Summation subelement, for the t in each pulse period_l.kThe pulse letter of the transmitting of aerial array described in moment Number pulsed beam in the grid positionPlace is formed by grid random radiation field and sums, the formula of the summation Son are as follows:

System provided in an embodiment of the present invention calculates each pulse week in the scatter echo arrived according to the antenna array receiver Interim t_l.kMoment is scattered back wave field, and defines the amendment random radiation field of the random radiation field, is scattered back wave field to described It is associated processing with the amendment random radiation field, obtains the process of the high-resolution imaging in the ground observation region, it is described Association process unit 806 may include:

Scatter echo field computation subelement, for being scattered back according to received by the receiving antenna in the aerial array Wave calculates t in each pulse period_l.kMoment is scattered back wave field, wherein calculating formula are as follows:

Subelement is defined, the pulsed beam of the pulse signal for being emitted by the aerial array is in each pulse period t_l.kThe random radiation field that moment is formed defines t in each pulse period_l,kThe amendment radiation field at moment are as follows:

And scatter echo field equation is indicated are as follows:

That is: E^sca=E^radσ, wherein σ is scattering coefficient matrix；

Association process subelement, for being scattered back wave field and the random spoke of amendment to described according to association process equation It penetrates field and is associated processing, obtain the high-resolution imaging in the ground observation region, wherein the association process equation are as follows:

Wherein,For the operator of relevance imaging algorithm.

All the embodiments in this specification are described in a progressive manner, same and similar portion between each embodiment Dividing may refer to each other, and each embodiment focuses on the differences from other embodiments.Especially for system or For system embodiment, since it is substantially similar to the method embodiment, so describing fairly simple, related place is referring to method The part of embodiment illustrates.System and system embodiment described above is only schematical, wherein the conduct The unit of separate part description may or may not be physically separated, component shown as a unit can be or Person may not be physical unit, it can and it is in one place, or may be distributed over multiple network units.It can root According to actual need that some or all of the modules therein is selected to achieve the purpose of the solution of this embodiment.Ordinary skill Personnel can understand and implement without creative efforts.

Professional further appreciates that, unit described in conjunction with the examples disclosed in the embodiments of the present disclosure And algorithm steps, can be realized with electronic hardware, computer software, or a combination of the two, in order to clearly demonstrate hardware and The interchangeability of software generally describes each exemplary composition and step according to function in the above description.These Function is implemented in hardware or software actually, the specific application and design constraint depending on technical solution.Profession Technical staff can use different methods to achieve the described function each specific application, but this realization is not answered Think beyond the scope of this invention.

The foregoing description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, as defined herein General Principle can be realized in other embodiments without departing from the spirit or scope of the present invention.Therefore, of the invention It is not intended to be limited to the embodiments shown herein, and is to fit to and the principles and novel features disclosed herein phase one The widest scope of cause.

Claims

1. a kind of unstable aerial platform microwave stares relevance imaging earth observation method characterized by comprising

Aerial array is obtained in the position data and attitude data at each positioning moment, wherein the two neighboring positioning moment Between time interval be preset locating periodically, the aerial array is using unstable aerial platform as carrier, and according to default Observation area emits pulse signal to the ground pulse period, and real-time reception is corresponding with the pulse signal is scattered back Wave；

According to the position data and attitude data, average translational velocity of the aerial array in each pulse period is calculated With average velocity of rotation；

According to the average translational velocity and average velocity of rotation, the aerial array is obtained in each pulse period t_l,kThe instantaneous position vector sum attitude angle at moment；Wherein, the t_l,kMoment is preset sampling in each pulse period Moment；

According to t in each pulse period_l.kThe instantaneous position vector sum attitude angle at moment, it is determining to be sent out with the aerial array The corresponding pulsed beam overlay area selection matrix of the pulsed beam for the pulse signal penetrated；

According to pulsed beam overlay area selection matrix, the pulsed beam of the pulse signal of the aerial array transmitting is determined The t in each pulse period_l,kThe random radiation field that moment is formed；

According to the antenna array receiver to scatter echo calculate t in each pulse period_l,kMoment is scattered back wave field, and The amendment random radiation field for defining the random radiation field is scattered back wave field and the amendment random radiation field is closed to described Connection processing, obtains the high-resolution imaging in the ground observation region.

2. the method according to claim 1, wherein described calculate the aerial array within each pulse period Average speed and average velocity of rotation, comprising:

Determine target polynomial fit curve equation；

According to the target polynomial fit curve equation, determine the aerial array in the initial time of each pulse period The position data and attitude data of position data and attitude data and finish time；

Position data and attitude data and the antenna array according to the aerial array in the initial time of each pulse period It is listed in the position data and attitude data of the finish time of each pulse period, calculates the aerial array in each pulse Average translational velocity and average velocity of rotation in period.

3. according to the method described in claim 2, it is characterized in that, the determining target polynomial fit curve equation, comprising:

Using preset polynomial fitting curve equation, to the aerial array obtained at each positioning moment Position data and attitude data carry out curve fitting, the polynomial fitting curve equation are as follows:

The coefficient a of the polynomial fitting curve equation is solved according to least square method_ξ,k, wherein the coefficient a_ξ,kSolution Equation are as follows:

Wherein, ζ_ti,posFor t_i,posThe position data and attitude data for the aerial array that moment positions, t_i,posIt is i-th The secondary positioning moment；

4. the method according to claim 1, wherein described according to the average translational velocity and average rotation speed Degree, obtains aerial array t in each pulse period_l,kMoment instantaneous position vector sum attitude angle, comprising:

By each transmitting antenna in the aerial array in any two neighboring positioning moment t_i,posAnd t_i+1,posBetween it is each T in a pulse period_l,kThe instantaneous position vector at momentIt indicates are as follows:

Wherein, n indicates n-th of transmitting antenna,For t_i,posThe position vector of n-th of transmitting antenna of moment is positioned, For in (t_l,k-t_i,pos) position vector variable quantity caused by the aerial array translation in time interval,For (t_l,k-t_i,pos) position vector variable quantity caused by each transmitting antenna rotation in time interval；

By the receiving antenna in the aerial array in two neighboring positioning moment t_i,posAnd t_i+1,posBetween each arteries and veins Rush t in the period_l,kThe instantaneous position vector at momentIt indicates are as follows:

According to average translational velocity of the aerial array within each pulse period andEquation is solved, is asked Solution obtains

Wherein, describedSolution equation are as follows:

Wherein, t_i,posThe moment is positioned within the l' pulse period, t_i+1,posThe moment is positioned in l " in a transmitting pulse period, The l pulse period is in the l' pulse period and the l " between a transmitting pulse period, i.e. l ' < l < l "；WithIt is respectively as follows: t in first of pulse period_l,kThe average translational velocity of aerial array described in moment, l' T in a pulse period_l,kThe average translational velocity of aerial array described in moment, t in the l'+1 pulse period_l,kDay described in moment T in -1 pulse period of the average translational velocity and l of linear array "_l,kThe average translational velocity of aerial array described in moment, T_P For the pulse period of the pulse signal；

According to average rotation speed of the aerial array within each pulse period, solution obtains the aerial array described T in each pulse period of pulse signal_l,kThe attitude angle at moment；Wherein, the solution equation of the attitude angle are as follows:

Wherein,θ、Pitch angle, azimuth and the roll angle of the aerial array are respectively indicated with φ；ω_l',α、 ω_l'+1,α、WithIt is respectively as follows: t in the l' pulse period_l,kThe average rotation speed of aerial array described in moment, l' T in+1 pulse period_l,kT in -1 pulse period of the average rotation speed of aerial array described in moment, l "_l,kDescribed in moment The average rotation speed of n-th transmitting antenna and t in first of pulse period in aerial array_l,kIn aerial array described in moment The average rotation speed of n transmitting antenna；

According to the attitude angle andEquation is solved, solution obtains

It is describedSolve equation are as follows:

Wherein,For t_i,posThe antenna coordinate system O at moment_b-x_by_bz_bIt is transformed into geographic coordinate system O-xyz's Coordinate transformation matrix,For in the antenna coordinate system O_b-x_by_bz_bUnder, the position of n-th of transmitting antenna in the aerial array Vector；

It is obtained according to solutionWithDetermine that the aerial array is believed in the pulse Number each pulse period in t_l,kThe instantaneous position vector sum attitude angle at moment.

5. the method according to claim 1, wherein the pulse signal of the determination and aerial array transmitting The corresponding pulsed beam overlay area selection matrix of pulsed beam, comprising:

According to the aerial array in each pulse period of the pulse signal t_l,kThe instantaneous position vector sum posture at moment Angle calculates t in each pulse period_l,kThe pulsed beam of pulse signal described in moment is formed by pulsed beam overlay area Center；

Based on the center, t in each pulse period is determined_l.kPulsed beam overlay area described in momentDescribedly The distribution of the face area of observation coverage, to the region of each pulsed beam coveringUnion calculating is carried out, determines imaging observation region S, Wherein, the region that the pulsed beam for the pulse signal that the imaging observation region S is emitted by the aerial array covers is in institute State the area of observation coverage of ground observation region formation；

The imaging observation region S is divided into M discretization grid, the M=P × Q, wherein P is orientation resolution cell Number, Q is distance to resolution cell number, and defines pulsed beam overlay area selection matrix are as follows:

Wherein, the l row of beam coverage area selection matrix D indicates t in first of pulse period_l,kThe hair of aerial array described in moment Distribution of the pulsed beam for the pulse signal penetrated in the imaging observation region S；

FoundationDetermine each element of the pulsed beam overlay area selection matrix D；Its In, elementIndicate m-th of grid target of the imaging observation region S whether by t in first of pulse period_l,kWhen The beam radiation field at quarter radiates,For the center of each grid in the imaging observation area S, m=1,2......M；

According to by each element in the determining pulsed beam overlay area selection matrix DDetermine with The corresponding pulsed beam overlay area selection matrix D of pulsed beam of the pulse signal of the aerial array transmitting.

6. according to the method described in claim 5, it is characterized in that, described select square according to the pulsed beam overlay area Battle array obtains the pulsed beam of the pulse signal of the aerial array transmitting t in each pulse period_l.kWhat the moment was formed Random radiation field, comprising:

According to the pulsed beam overlay area selection matrix D and preset random radiation field computation formula, it is calculated each Pulse period t_l,kAt the moment, the pulsed beam of the pulse signal of the aerial array transmitting is in the grid position of the imaging observation area S It setsPlace is formed by grid random radiation field；

The preset random radiation field computation formula are as follows:

Wherein, c=3 × 10⁸M/s, ForGrid position under momentRelative in the aerial array The phase centre location vector of n-th of transmitting antennaDirection in space unit vector,For n-th of transmitting day The pattern function of line, s_n(t) pulse signal of n-th of transmitting antenna of t moment transmitting is indicated；

To the t in each pulse period_l.kThe pulsed beam of the pulse signal of the transmitting of aerial array described in moment is in the net Case is setPlace is formed by grid random radiation field and sums, the formula of the summation are as follows:

Obtain the pulsed beam of the pulse signal of the aerial array transmitting t in each pulse period_l.kWhat the moment was formed Random radiation field.

7. according to the method described in claim 6, it is characterized in that, the scatter echo arrived according to the antenna array receiver Calculate t in each pulse period_l.kMoment is scattered back wave field, and defines the amendment random radiation field of the random radiation field, right It is described to be scattered back wave field and the amendment random radiation field is associated processing, obtain the high-resolution in the ground observation region at Picture, comprising:

According to scatter echo received by the receiving antenna in the aerial array, t in each pulse period is calculated_l.kMoment It is scattered back wave field, wherein scatter echo field computation formula are as follows:

Wherein, c=3 × 10⁸M/s, ForGrid position under momentRelative in the aerial array Receiving antenna phase centre location vectorDirection in space unit vector,For receiving antenna in the aerial array Pattern function,For grid positionThe scattering coefficient at place；

The pulsed beam of the pulse signal emitted by the aerial array t in each pulse period_l.kThe random spoke that moment is formed It penetrates field and defines t in each pulse period_l,kMoment corrects random radiation field are as follows:

And scatter echo field equation is indicated are as follows:

That is: E^sca=E^radσ, wherein σ is scattering coefficient matrix；

According to association process equation, wave field is scattered back and the amendment random radiation field is associated processing to described, obtains institute State the high-resolution imaging in ground observation region, wherein the association process equation are as follows:

Wherein,For the operator of relevance imaging algorithm.

8. a kind of unstable aerial platform microwave stares relevance imaging earth observation systems, comprising:

Computing unit, for calculating the aerial array in each pulse period according to the position data and attitude data Average translational velocity and average velocity of rotation；

Second acquisition unit, for obtaining the aerial array each according to the average translational velocity and average velocity of rotation T in a pulse period_l,kThe instantaneous position vector sum attitude angle at moment；Wherein, the t_l,kMoment is each pulse Preset sampling instant in period；

First determination unit, for according to t in each pulse period_l.kThe instantaneous position vector sum attitude angle at moment determines Pulsed beam overlay area selection matrix corresponding with the pulsed beam of pulse signal of aerial array transmitting；

Second determination unit, for determining the aerial array transmitting according to pulsed beam overlay area selection matrix The pulsed beam of pulse signal t in each pulse period_l,kThe random radiation field that moment is formed；

Association process unit, for according to the antenna array receiver to scatter echo calculate t in each pulse period_l.kWhen That carves is scattered back wave field, and defines the amendment random radiation field of the random radiation field, is scattered back wave field to described and described repairs Positive random radiation field is associated processing, obtains the high-resolution imaging in the ground observation region；

Wherein, the first acquisition unit, computing unit, second acquisition unit, the first determination unit, the second determination unit and pass Connection processing unit is set to high accuracy positioning and determines appearance subsystem, and the high accuracy positioning determines appearance subsystem and is fixed on the antenna array The array center of column；

Aerial array, for the transmitting of observation area to the ground pulse signal, simultaneously real-time reception is corresponding with the pulse signal scattered It is emitted back towards wave.

9. system according to claim 8, which is characterized in that the aerial array includes multiple transmitting antennas and at least one A receiving antenna.

10. system according to claim 8, which is characterized in that further include:

Self-adapting type can be changed suspension subsystem, for adjusting the relative position of the aerial array Yu the ground observation region.