CN105005841A - Method of synthesizing imaging satellite meta-task and device of synthesizing imaging satellite meta-task - Google Patents

Abstract

The present invention discloses a method of synthesizing an imaging satellite meta-task and a device of synthesizing the imaging satellite meta-task which can save the satellite resources. The method comprises the steps of obtaining a plurality of meta-tasks located in a view field angle range of an imaging satellite sensor; generating a first intermediate task and a second intermediate task according to the plurality of meta-tasks, wherein the lateral swing angle, the time window starting time, the time window ending time and the shortest execution duration of the first intermediate task are defined as theta x, wsx, wex and dx respectively, and the lateral swing angle, the time window starting time, the time window ending time and the shortest execution duration of the second intermediate task are defined as theta y, wsy, wey and dy respectively; determining whether the theta x, wsx, wex and dx and the theta y, wsy, wey and dy satisfy the preset conditions, if yes, synthesizing the plurality of meta tasks into a synthesis task.

Description

The method of compound imaging satellite Meta task and device

Technical field

The present invention relates to imaging satellite task synthesis technical field, be specifically related to a kind of method and device of compound imaging satellite Meta task.

Background technology

Imaging satellite has the features such as Polaroid scope is large, imaging cost is low, has been widely used in the fields such as national defence, environmental protection, agricultural, meteorology, calamity emergency.But, imaging satellite development, launch and maintenance cost high, although along with the development of satellite application technology, increasing imaging satellite soar into space, the imaging demand growing relative to the mankind, satellite resource is still extremely valuable.In order to most optimally utilize imaging satellite resource, satellite task planning is particularly important.Namely satellite task planning consider the constraints such as satellite imagery ability and mission requirements, to arrange task income and to be optimization aim to the maximum, determines the task that will perform and the time window beginning and ending time performing these tasks.Some typical mission planning algorithms comprise greedy algorithm, tabu search, linear programming relax, genetic algorithm, evolution algorithm, heuritic approach, Lagrangian relaxation technology etc.

When observed object corresponding to different imaging task is when nearer, by adjusting the imaging side-sway angle of satellite borne sensor, extend the on time of sensor, task synthesis observation is carried out to multiple observed object.The synthesis of satellite imagery task refers to, according to certain rule, several can be merged into a task by an once Meta task performed that passes by of satellite.As shown in Fig. 2 (a0) and 2 (a1), the sensor of a satellite, through observed object overhead, takes a band with certain fabric width and length.The length of band and width are by the height of satellite, and the field angle of sensor, the side-sway angle of sensor and the lasting observation time of sensor determine.Generally speaking, height and the sensor field of view angle of satellite are fixing, and we can decide the position and the size that cover observed object band by the side-sway angle and lasting observation time adjusting sensor.The imageable target studied herein is point target, and satellite is once observed and can be completed imaging.An observed object can be considered as a Meta task, and two or more tasks of closing on can merge into a task.As shown in Fig. 2 (b0), 2 (b1), 2 (c0) and 2 (c1), two observation mission T1 and T2 can be merged into a task, just can be completed by the once shooting of satellite.The synthesis of research satellite imaging task has great significance.First, this can be avoided satellite, and side-sway is movable frequently, reduces switching on and shutting down number of times, is conducive to protecting satellite sensor.Secondly, the side-looking imaging number of times in some imaging satellites each track circle time has strict restriction, and get task synthesis observation, so satellite flight one circle can complete more observation mission.In addition, task synthesis can reduce the solution space of mission planning, improves the utilization rate of satellite.Therefore, consider that task synthesis is most important to the observing capacity improving existing imaging satellite.Task synthesis reduces sensing switch machine number of times and side-sway number of times for satellite, reduces energy ezpenditure, completes more multitask and have great importance.

When satellite task synthetic method is applied in satellite task planning, we need judgement two Meta task can synthesize in what situations, and how to build synthesis task.As shown in Fig. 2 (a0) and 2 (a1), ground target, once have been passed by observation by satellite, so be referred to as Meta task.Make S={s ₁, s ₂..., s _mbe expressed as the set of picture satellite resource.A Meta task usual binding time window tasks carrying duration with a side-sway angle wherein with represent start time and the end time of time window.For convenience of representing, herein to omit subscript s in lower part.For example, i-th Meta task on s satellite is then expressed as T _i={ W _i, d _i, θ _i.

Task T _iif can be performed by a satellite, so necessarily in the SEE time window of this satellite, select one section and be no less than d _iperiod, namely

$\left\{\begin{array}{c}t{e}_i-t{s}_i\≥d_i\\ t{s}_i\≥w{s}_i\\ t{e}_i\≤w{e}_i\end{array}\right..$

Wherein ts _iand te _irepresent that task starts the moment of moment and the end performed respectively, ws _iand we _ialso be task T respectively _iearliest start time end time the latest

Suppose T _i,jbe a synthesis task, it is by two Meta task T _iand T _jsynthesis.When reality performs T _i,jtime be greater than the execution duration d that required by task wants _i,jtime, so will waste the valuable satellite resource of a part to complete this task.

When the redundancy time actual execution time referred to when task of synthesis window task time is greater than the execution time that required by task wants, i.e. te _i,j-ts _i,j>d _i,j, so in time window, some time is wasted, and this part time is called as redundancy time.

From Fig. 2 (a0) and 2 (a1), terrain object 1,2, and 3 can as 3 Meta task T ₁, T ₂and T ₃, complete observation imaging by two satellites.As shown in Fig. 2 (b0), 2 (b1), 2 (c0) and 2 (c1), satellite also can by performing synthesis task T _1,2with Meta task T ₃carry out the imaging to these three targets.Fig. 2 (b0) and 2 (b1) is to there is redundancy time in the former generated time window with the difference of 2 (c0) and 2 (c1), and the latter is not.

Some are thought, if imaging task T to the research of the satellite task planning problem of consideration task synthesis ₁and T ₂can synthesize, following two conditions [18,19,20,22,23] must be met:

$\left\{\begin{array}{c}\max \{{\mathrm{we}}_1,{\mathrm{we}}_2\}-\min \{{\mathrm{ws}}_1,{\mathrm{ws}}_2\}\≤\mathrm{\Δ}{d}_s\\ |{\mathrm{\θ}}_1-{\mathrm{\θ}}_2|\≤\mathrm{\Δ}{\mathrm{\θ}}_s\end{array}\right.,$

Wherein Δ d _s, Δ θ _srepresent single imaging on time and the field angle of satellite s respectively.

If imaging task T ₁and T ₂can synthesize, so synthesize task T _1,2time window and side-sway angle be:

$\left\{\begin{array}{c}{W}_{\mathrm{1,2}}=\left[\min \right\{{\mathrm{ws}}_1,{\mathrm{ws}}_2\},\max \{{\mathrm{we}}_1,{\mathrm{we}}_2\left\}\right]\\ {\mathrm{\θ}}_{\mathrm{1,2}}=\frac{{\mathrm{\θ}}_1+{\mathrm{\θ}}_2}{2}\end{array}\right..$

This conventional synthesis mode does not consider the execution duration of synthesis task.The execution duration of task refers to and calculates according to the orbit parameter of imaging satellite and the geographic position of imaging task, is satellite carries out the time of imaging to this task.In the process of task scheduling, this time can not change, and thus also can regard an attribute of imaging task as.When satellite orbit is higher or satellite borne sensor field range is larger, the SEE time length of window of satellite is often greater than satellite to the real time needed for target observation, and satellite performs imaging task only need choose a period of time imaging in SEE time window.The mode of this task synthesis, makes to there is redundancy time in generated time window, as shown in Fig. 2 (b0) and 2 (b1).In satellite task planning, if take the thought that above-mentioned normal work to do synthesizes, task of likely causing some originally can synthesize cannot be synthesized, and the imaging session time that the imaging task simultaneously synthesized requires is not the theoretic shortest time; In addition, the imaging side-sway angle after synthesis minimumly in theory neither can observe task T simultaneously ₁and T ₂the imaging side-sway angle of corresponding observed object.

It can thus be appreciated that the synthesis task of conventional task synthetic method structure can not make full use of satellite resource, thus causes the waste of satellite resource.

Summary of the invention

The object of the invention is to, a kind of method and device of compound imaging satellite Meta task is provided, can satellite resource be made full use of, thus can satellite resource be saved.

For this purpose, on the one hand, the present invention proposes a kind of method of compound imaging satellite Meta task, comprising:

S1, obtains the multiple Meta task T be within the scope of the field angle of same imaging satellite sensor ₁, T ₂, T ₃..., T _n;

S2, according to described multiple Meta task T ₁, T ₂, T ₃..., T _ngenerate the first middle task and the second middle task; The side-sway angle of described first middle task, the start time of time window, end time and the shortest execution duration are respectively θ _x, ws _x, we _xand d _x, the side-sway angle of described second middle task, the start time of time window, end time and the shortest execution duration are respectively θ _y, ws _y, we _yand d _y;

S3, judges described θ _x, ws _x, we _xand d _x, and described θ _y, ws _y, we _yand d _ywhether meet

(ws _y+ d _y)-(we _x-d _x)≤Δ d _s(ws _x≤ ws _y) and | θ _x-θ _y|≤Δ θ _s

Or (ws _x+ d _x)-(we _y-d _y)≤Δ d _s(ws _y<ws _x) and | θ _x-θ _y|≤Δ θ _s,

Wherein, described Δ d _s, Δ θ _srepresent single imaging on time and the field angle of described imaging satellite s respectively,

If meet, then by described multiple Meta task T ₁, T ₂, T ₃..., T _nsynthesize synthesis task,

If meet

(ws _y+ d _y)-(we _x-d _x)≤Δ d _s(ws _x≤ ws _y) and | θ _x-θ _y|≤Δ θ _s,

The side-sway angle of described synthesis task is θ _x,y,

${\mathrm{\&theta;}}_{x,y}=\left\{\begin{array}{cc}\max \{{\mathrm{\&theta;}}_x-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \min \{{\mathrm{\&theta;}}_x+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x<0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \max \{{\mathrm{\&theta;}}_y-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\\ \min \{{\mathrm{\&theta;}}_y+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y<0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\end{array}\right.,$

The start time of the time window of described synthesis task is ws _x,y,

${\mathrm{ws}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{we}}_x-d_x,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min \{{\mathrm{ws}}_y,\max ({\mathrm{ws}}_x,{\mathrm{ws}}_y+d_y-d_x)\},& \mathrm{else}\end{array}\right.,$

The end time of the time window of described synthesis task is we _x,y,

${\mathrm{we}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_y+d_y,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min ({\mathrm{we}}_x-d_x,{\mathrm{we}}_y-d_y)+\max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

The shortest execution duration of described synthesis task is d _x,y,

$d_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_y+d_y-({\mathrm{we}}_x-d_x),& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

If meet

(ws _x+ d _x)-(we _y-d _y)≤Δ d _s(ws _y<ws _x) and | θ _x-θ _y|≤Δ θ _s,

The side-sway angle of described synthesis task is θ _x,y,

${\mathrm{\&theta;}}_{x,y}=\left\{\begin{array}{cc}\max \{{\mathrm{\&theta;}}_y-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_y\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_x\right|\\ \min \{{\mathrm{\&theta;}}_y+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y<0,\left|{\mathrm{\&theta;}}_y\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_x\right|\\ \max \{{\mathrm{\&theta;}}_x-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_x\right|>\left|{\mathrm{\&theta;}}_y\right|\\ \min \{{\mathrm{\&theta;}}_x+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x<0,\left|{\mathrm{\&theta;}}_x\right|>\left|{\mathrm{\&theta;}}_y\right|\end{array}\right.,$

The start time of the time window of described synthesis task is ws _x,y,

${\mathrm{ws}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{we}}_y-d_y,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min \{{\mathrm{ws}}_x,\max ({\mathrm{ws}}_y,{\mathrm{ws}}_x+d_x-d_y)\},& \mathrm{else}\end{array}\right.,$

The end time of the time window of described synthesis task is we _x,y,

${\mathrm{we}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_x+d_x,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min ({\mathrm{we}}_y-d_y,{\mathrm{we}}_x-d_x)+\max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

The shortest execution duration of described synthesis task is d _x,y,

$d_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_x+d_x-({\mathrm{we}}_y-d_{x}y),& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \max \{d_x,d_y\},& \mathrm{else}\end{array}\right..$

On the other hand, the present invention proposes a kind of device of compound imaging satellite Meta task, comprising:

Acquiring unit, for obtain be in same imaging satellite sensor field angle within the scope of multiple Meta task T ₁, T ₂, T ₃..., T _n;

Middle task generation unit, for according to described multiple Meta task T ₁, T ₂, T ₃..., T _ngenerate the first middle task and the second middle task; The side-sway angle of described first middle task, the start time of time window, end time and the shortest execution duration are respectively θ _x, ws _x, we _xand d _x, the side-sway angle of described second middle task, the start time of time window, end time and the shortest execution duration are respectively θ _y, ws _y, we _yand d _y;

Synthesis task generation unit, for judging described θ _x, ws _x, we _xand d _x, and described θ _y, ws _y, we _yand d _ywhether meet

(ws _y+ d _y)-(we _x-d _x)≤Δ d _s(ws _x≤ ws _y) and | θ _x-θ _y|≤Δ θ _s

Or (ws _x+ d _x)-(we _y-d _y)≤Δ d _s(ws _y<ws _x) and | θ _x-θ _y|≤Δ θ _s,

Wherein, described Δ d _s, Δ θ _srepresent single imaging on time and the field angle of described imaging satellite s respectively,

If meet, then by described multiple Meta task T ₁, T ₂, T ₃..., T _nsynthesize synthesis task,

If meet

(ws _y+ d _y)-(we _x-d _x)≤Δ d _s(ws _x≤ ws _y) and | θ _x-θ _y|≤Δ θ _s,

The side-sway angle of described synthesis task is θ _x,y,

${\mathrm{\&theta;}}_{x,y}=\left\{\begin{array}{cc}\max \{{\mathrm{\&theta;}}_x-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \min \{{\mathrm{\&theta;}}_x+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x<0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \max \{{\mathrm{\&theta;}}_y-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\\ \min \{{\mathrm{\&theta;}}_y+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y<0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\end{array}\right.,$

The start time of the time window of described synthesis task is ws _x,y,

${\mathrm{ws}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{we}}_x-d_x,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min \{{\mathrm{ws}}_y,\max ({\mathrm{ws}}_x,{\mathrm{ws}}_y+d_y-d_x)\},& \mathrm{else}\end{array}\right.,$

The end time of the time window of described synthesis task is we _x,y,

${\mathrm{we}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_y+d_y,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min ({\mathrm{we}}_x-d_x,{\mathrm{we}}_y-d_y)+\max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

The shortest execution duration of described synthesis task is d _x,y,

$d_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_y+d_y-({\mathrm{we}}_x-d_x),& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

If meet

(ws _x+ d _x)-(we _y-d _y)≤Δ d _s(ws _y<ws _x) and | θ _x-θ _y|≤Δ θ _s,

The side-sway angle of described synthesis task is θ _x,y,

${\mathrm{\&theta;}}_{x,y}=\left\{\begin{array}{cc}\max \{{\mathrm{\&theta;}}_y-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_y\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_x\right|\\ \min \{{\mathrm{\&theta;}}_y+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y<0,\left|{\mathrm{\&theta;}}_y\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_x\right|\\ \max \{{\mathrm{\&theta;}}_x-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_x\right|>\left|{\mathrm{\&theta;}}_y\right|\\ \min \{{\mathrm{\&theta;}}_x+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x<0,\left|{\mathrm{\&theta;}}_x\right|>\left|{\mathrm{\&theta;}}_y\right|\end{array}\right.,$

The start time of the time window of described synthesis task is ws _x,y,

${\mathrm{ws}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{we}}_y-d_y,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min \{{\mathrm{ws}}_x,\max ({\mathrm{ws}}_y,{\mathrm{ws}}_x+d_x-d_y)\},& \mathrm{else}\end{array}\right.,$

The end time of the time window of described synthesis task is we _x,y,

${\mathrm{we}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_x+d_x,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min ({\mathrm{we}}_y-d_y,{\mathrm{we}}_x-d_x)+\max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

The shortest execution duration of described synthesis task is d _x,y,

$d_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_x+d_x-({\mathrm{we}}_y-d_{x}y),& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \max \{d_x,d_y\},& \mathrm{else}\end{array}\right..$

The method of the compound imaging satellite Meta task described in the embodiment of the present invention and device, the synthesis task side-sway angle that the synthetic method compared to routine being in the synthesis task of the multiple Meta task synthesis within the scope of the field angle of same imaging satellite sensor is synthesized is minimum, and time window does not have redundancy time, thus than the task synthetic method of routine, more task can be synthesized, and the side-sway angle of the synthesis task of synthesis is less, execution time is shorter, thus the start number of times of satellite borne sensor can be reduced, reduce the energy loss of satellite, thus can satellite resource be saved.

Accompanying drawing explanation

Fig. 1 is the schematic flow sheet of method one embodiment of compound imaging satellite Meta task of the present invention;

In Fig. 2, (a0) is the schematic diagram of satellite imagery task, (a1) be the schematic diagram of the time window of satellite imagery task, (b0) be the schematic diagram of conventional satellite imaging task synthesis, (b1) be the schematic diagram of the time window of the synthesis task of conventional satellite imaging task synthesis, (c0) be schematic diagram that another embodiment Satellite imaging task of method of compound imaging satellite Meta task of the present invention synthesizes, (c1) schematic diagram of the time window of the synthesis task of synthesizing for another embodiment Satellite imaging task of method of compound imaging satellite Meta task of the present invention,

Fig. 3 is task T ₁with task T ₂time window relative position distribution schematic diagram;

Fig. 4 is for the task T shown in Fig. 3 ₁with task T ₂the schematic diagram of the time window of the synthesis task of synthesis;

Fig. 5 is task T _iand T _jthe common factor schematic diagram of time window;

Fig. 6 is the frame structure schematic diagram of device one embodiment of compound imaging satellite Meta task of the present invention.

Embodiment

For making the object of the embodiment of the present invention, technical scheme and advantage clearly, below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly described, obviously, described embodiment is the present invention's part embodiment, instead of whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art, not making the every other embodiment obtained under creative work prerequisite, belong to the scope of protection of the invention.

As shown in Figure 1, the present embodiment discloses a kind of method of compound imaging satellite Meta task, comprising:

S1, obtains the multiple Meta task T be within the scope of the field angle of same imaging satellite sensor ₁, T ₂, T ₃..., T _n;

S2, according to described multiple Meta task T ₁, T ₂, T ₃..., T _ngenerate the first middle task and the second middle task; The side-sway angle of described first middle task, the start time of time window, end time and the shortest execution duration are respectively θ _x, ws _x, we _xand d _x, the side-sway angle of described second middle task, the start time of time window, end time and the shortest execution duration are respectively θ _y, ws _y, we _yand d _y;

S3, judges described θ _x, ws _x, we _xand d _x, and described θ _y, ws _y, we _yand d _ywhether meet

(ws _y+ d _y)-(we _x-d _x)≤Δ d _s(ws _x≤ ws _y) and | θ _x-θ _y|≤Δ θ _s

Or (ws _x+ d _x)-(we _y-d _y)≤Δ d _s(ws _y<ws _x) and | θ _x-θ _y|≤Δ θ _s,

Wherein, described Δ d _s, Δ θ _srepresent single imaging on time and the field angle of described imaging satellite s respectively,

If meet, then by described multiple Meta task T ₁, T ₂, T ₃..., T _nsynthesize synthesis task,

If meet

(ws _y+ d _y)-(we _x-d _x)≤Δ d _s(ws _x≤ ws _y) and | θ _x-θ _y|≤Δ θ _s,

The side-sway angle of described synthesis task is θ _x,y,

${\mathrm{\&theta;}}_{x,y}=\left\{\begin{array}{cc}\max \{{\mathrm{\&theta;}}_x-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \min \{{\mathrm{\&theta;}}_x+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x<0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \max \{{\mathrm{\&theta;}}_y-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\\ \min \{{\mathrm{\&theta;}}_y+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y<0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\end{array}\right.,$

The start time of the time window of described synthesis task is ws _x,y,

${\mathrm{ws}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{we}}_x-d_x,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min \{{\mathrm{ws}}_y,\max ({\mathrm{ws}}_x,{\mathrm{ws}}_y+d_y-d_x)\},& \mathrm{else}\end{array}\right.,$

The end time of the time window of described synthesis task is we _x,y,

${\mathrm{we}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_y+d_y,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min ({\mathrm{we}}_x-d_x,{\mathrm{we}}_y-d_y)+\max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

The shortest execution duration of described synthesis task is d _x,y,

$d_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_y+d_y-({\mathrm{we}}_x-d_x),& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

If meet

(ws _x+ d _x)-(we _y-d _y)≤Δ d _s(ws _y<ws _x) and | θ _x-θ _y|≤Δ θ _s,

The side-sway angle of described synthesis task is θ _x,y,

${\mathrm{\&theta;}}_{x,y}=\left\{\begin{array}{cc}\max \{{\mathrm{\&theta;}}_y-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_y\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_x\right|\\ \min \{{\mathrm{\&theta;}}_y+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y<0,\left|{\mathrm{\&theta;}}_y\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_x\right|\\ \max \{{\mathrm{\&theta;}}_x-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_x\right|>\left|{\mathrm{\&theta;}}_y\right|\\ \min \{{\mathrm{\&theta;}}_x+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x<0,\left|{\mathrm{\&theta;}}_x\right|>\left|{\mathrm{\&theta;}}_y\right|\end{array}\right.,$

The start time of the time window of described synthesis task is ws _x,y,

${\mathrm{ws}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{we}}_y-d_y,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min \{{\mathrm{ws}}_x,\max ({\mathrm{ws}}_y,{\mathrm{ws}}_x+d_x-d_y)\},& \mathrm{else}\end{array}\right.,$

The end time of the time window of described synthesis task is we _x,y,

${\mathrm{we}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_x+d_x,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min ({\mathrm{we}}_y-d_y,{\mathrm{we}}_x-d_x)+\max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

The shortest execution duration of described synthesis task is d _x,y,

$d_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_x+d_x-({\mathrm{we}}_y-d_{x}y),& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \max \{d_x,d_y\},& \mathrm{else}\end{array}\right..$

The method of the compound imaging satellite Meta task described in the embodiment of the present invention, the synthesis task side-sway angle that the synthetic method compared to routine being in the synthesis task of the multiple Meta task synthesis within the scope of the field angle of same imaging satellite sensor is synthesized is minimum, and time window does not have redundancy time, thus than the task synthetic method of routine, more task can be synthesized, and the side-sway angle of the synthesis task of synthesis is less, execution time is shorter, thus the start number of times of satellite borne sensor can be reduced, reduce the energy loss of satellite, thus can satellite resource be saved.

Alternatively, in another embodiment of the method for compound imaging satellite Meta task of the present invention, if n is greater than 2,

Described according to described multiple Meta task T ₁, T ₂, T ₃..., T _ngenerate the first middle task and the second middle task, comprising:

By described multiple Meta task T ₁, T ₂, T ₃..., T _nsynthesize synthesis task T _{1, n-1},

According to described synthesis task T _{1, n-1}with described Meta task T _ngenerate the first middle task and the second middle task;

Described θ _x=max (max (θ ₁, 0), max (θ ₂, 0) ... max (θ _n, 0)),

Described ${\mathrm{ws}}_x=\left\{\begin{array}{ccc}{\mathrm{ws}}_n& \mathrm{if}& {\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{ws}}_{1.n-1}& & \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_x=\left\{\begin{array}{ccc}{\mathrm{we}}_n& \mathrm{if}& {\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{we}}_{1.n-1}& & \mathrm{else}\end{array}\right.,$

Described $d_x=\left\{\begin{array}{ccc}{d}_n& \mathrm{if}& {\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ d_{1.n-1}& & \mathrm{else}\end{array}\right.,$

Described θ _y=min (min (θ ₁, 0), min (θ ₂, 0) ... min (θ _n, 0)),

Described ${\mathrm{ws}}_y=\left\{\begin{array}{ccc}{\mathrm{ws}}_{1.n-1}& \mathrm{if}& {\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{ws}}_n& & \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_y=\left\{\begin{array}{ccc}{\mathrm{we}}_{1.n-1}& \mathrm{if}& {\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{we}}_n& & \mathrm{else}\end{array}\right.,$

Described $d_y=\left\{\begin{array}{ccc}{d}_{1.n-1}& \mathrm{if}& {\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ d_n& & \mathrm{else}\end{array}\right.,$

Wherein, described θ _p(p ∈ (1,2 ..., n)) and be Meta task T _pside-sway angle, described ws _n, we _nand d _nbe respectively Meta task T _nstart time of time window, end time and the shortest execution duration, described ws _{1, n-1}, we _{1, n-1}and d _{1, n-1}be respectively described synthesis task T _{1, n-1}start time of time window, end time and the shortest execution duration.

Alternatively, in another embodiment of the method for compound imaging satellite Meta task of the present invention, if n is 2,

Described θ _x=max (max (θ ₁, 0), max (θ ₂, 0)),

Described ${\mathrm{ws}}_x=\left\{\begin{array}{ccc}{\mathrm{ws}}_2& \mathrm{if}& {\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{ws}}_1& & \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_x=\left\{\begin{array}{ccc}{\mathrm{we}}_2& \mathrm{if}& {\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{we}}_1& & \mathrm{else}\end{array}\right.,$

Described $d_x=\left\{\begin{array}{ccc}{d}_2& \mathrm{if}& {\mathrm{ws}}_1>{\mathrm{ws}}_2\\ d_1& & \mathrm{else}\end{array}\right.,$

Described θ _y=min (min (θ ₁, 0), min (θ ₂, 0)),

Described ${\mathrm{ws}}_y=\left\{\begin{array}{ccc}{\mathrm{ws}}_1& \mathrm{if}& {\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{ws}}_2& & \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_y=\left\{\begin{array}{ccc}{\mathrm{we}}_1& \mathrm{if}& {\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{we}}_2& & \mathrm{else}\end{array}\right.,$

Described $d_y=\left\{\begin{array}{ccc}{d}_1& \mathrm{if}& {\mathrm{ws}}_1>{\mathrm{ws}}_2\\ d_2& & \mathrm{else}\end{array}\right..$

Without loss of generality, two Meta task T are supposed _iand T _j, and T _icompare T _jthe more early (ws that starts of time window _i≤ ws _j), then task T _iand T _jthe sufficient and necessary condition that can synthesize is (ws _j+ d _j)-(we _i-d _i)≤Δ d _sor | θ _i-θ _j|≤Δ θ _s, wherein | θ _i-θ _j| refer to the absolute value of the difference at two Meta task side-sway angles.

For a Meta task T _i, its shortest execution duration d _idetermine, during actual this task of execution, in SEE time window, d can be not less than by arbitrary continuation _iperiod in perform.And for synthesis task, its shortest execution duration is then the shortest time that satellite can complete Meta task simultaneously.Therefore, the shortest execution duration depends on the common factor of two Meta task time windows and their respective execution durations.Two Meta task T _iand T _jtime window [ws _i, we _i] and [ws _j, we _j] there are three kinds of relations in time: from, intersect, comprise.By the overlap length of two time windows | W _{1 ∩ 2}| with task T _i, T _jexecution time d _i, d _jthe magnitude relationship of three is divided into | W _{1 ∩ 2}| <min (d ₁, d ₂) and | W _{1 ∩ 2}|>=min (d ₁, d ₂).By the set relations between two time windows and time windows overlay length and task T in Fig. 3 ₁and T ₂execution duration between magnitude relationship, list imaging task T ₁with imaging task T ₂9 kinds of situations of time window relative position distribution, Fig. 4 is the time window of the synthesis task of each situation synthesis in Fig. 3.Task T _iand T _jthe sufficient and necessary condition that can synthesize is (ws _j+ d _j)-(we _i-d _i)≤Δ d _s, be described as follows:

Prove adequacy, namely prove as (ws _j+ d _j) _-(we _i-d _i)≤Δ d _sduring establishment, two Meta task T _iand T _jcan synthesize, namely as (ws _j+ d _j)-(we _i-d _i)≤Δ d _sduring establishment, life period window and Meta task T _iand T _jsEE time windows overlay degree be more than or equal to the execution duration d of Meta task respectively _i, d _j, and this time window length is less than satellite sensor single maximum start duration Δ d _s.Namely prove that existence makes $\left\{\begin{array}{c}|W\&cap;W_i|\&GreaterEqual;d_i\\ |W\&cap;W_j|\&GreaterEqual;d_j\\ \mathrm{we}-\mathrm{ws}\&le;\mathrm{\&Delta;}{d}_s\end{array}\right.$ Time window W=[ws, the we] set up.

1) as | W _i∩ W _j|≤min (d _i, d _j) time,

Make ws=we _i-d _i, we=ws _j+ d _j, so | W ∩ W _i|=d _i, | W ∩ W _j|=d _j, then we-ws=(ws _j+ d _j)-(we _i-d _i)≤Δ d _s.Therefore, formula $\left\{\begin{array}{c}|W\&cap;W_i|\&GreaterEqual;d_i\\ |W\&cap;W_j|\&GreaterEqual;d_j\\ \mathrm{we}-\mathrm{ws}\&le;\mathrm{\&Delta;}{d}_s\end{array}\right.$ Set up.

2) as | W _i∩ W _j|>=min (d _i, d _j) time,

Without loss of generality, d is supposed _i>=d _j.Make ws=ws _i, we=we _i, then W=W _i.Due to W _ibe the time window of a Meta task, can d be obtained _i≤ | W _i|≤Δ d _s.Again because of | W _i∩ W _j|>=min (d _i, d _j)=d _j, so | W ∩ W _j|>=d _j.Therefore, formula $\left\{\begin{array}{c}|W\&cap;W_i|\&GreaterEqual;d_i\\ |W\&cap;W_j|\&GreaterEqual;d_j\\ \mathrm{we}-\mathrm{ws}\&le;\mathrm{\&Delta;}{d}_s\end{array}\right.$ Set up.

Prove necessity, namely prove when two Meta task Ti and Tj can synthesize, (ws _j+ d _j)-(we _i-d _i)≤Δ d _smust set up.

If the time window of two Meta task can merge, so synthesize the time window W of task _i,j=[ws _i,j, we _i,j] must meet

$\left\{\begin{array}{c}|W_{i,j}\&cap;W_i|\&GreaterEqual;d_i\\ |W_{i,j}\&cap;W_j|\&GreaterEqual;d_j\\ {\mathrm{we}}_{i,j}-{\mathrm{ws}}_{i,j}\&le;\mathrm{\&Delta;}{d}_s\\ d_{i,j}\&GreaterEqual;\max (d_i,d_j)\end{array}\right..$

Due to | W _i,j∩ W _i|>=d _i, known ws _i,j≤ we _i-d _i.In like manner, by | W _i,j∩ W _j|>=d _j, can we be obtained _i,j>=ws _j+ d _j.So (ws _j+ d _j)-(we _i-d _i)≤we _i,j-ws _i,j≤ Δ d _s.Therefore (ws _j+ d _j)-(we _i-d _i)≤Δ d _s.

In the time window of synthesis task, there is not redundancy time and its side-sway angle is minimum, so this task is referred to as compact synthesis task.Without loss of generality, two Meta task T are supposed _iand T _j, and T _icompare T _jthe more early (ws that starts of time window _i≤ ws _j), if so Meta task T _iand T _ja compact synthesis task T can be synthesized _i,j={ W _i,j, d _i,j, θ _i,j, then synthesize the start time ws of task _i,j, end time we _i,j, the shortest execution duration d _i,j, minimum imaging side-sway angle θ _i,jbe respectively:

${\mathrm{ws}}_{i,j}=\left\{\begin{array}{cc}{\mathrm{we}}_i-d_i,& \mathrm{if}|W_i\&cap;W_j|\&le;\min (d_i,d_j)\\ \min \{{\mathrm{ws}}_j,\max ({\mathrm{ws}}_i,{\mathrm{ws}}_j+d_j-d_i)\},& \mathrm{else}\end{array}\right.,$

${\mathrm{we}}_{i,j}=\left\{\begin{array}{cc}{\mathrm{ws}}_j+d_j,& \mathrm{if}|W_i\&cap;W_j|\&le;\min (d_i,d_j)\\ \min ({\mathrm{we}}_i-d_i,{\mathrm{we}}_j-d_j)+\max \{d_i,d_j\},& \mathrm{else}\end{array}\right.,$

$d_{i,j}=\left\{\begin{array}{cc}{\mathrm{ws}}_j+d_j-({\mathrm{we}}_i-d_i),& \mathrm{if}|W_i\&cap;W_j|\&le;\min (d_i,d_j)\\ \max \{d_i,d_j\},& \mathrm{else}\end{array}\right.,$

${\mathrm{\&theta;}}_{x,y}=\left\{\begin{array}{cc}\max \{{\mathrm{\&theta;}}_x-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \min \{{\mathrm{\&theta;}}_x+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x<0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \max \{{\mathrm{\&theta;}}_y-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\\ \min \{{\mathrm{\&theta;}}_y+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y<0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\end{array}\right.,$

Here we suppose side-sway angle | θ _i| be more than or equal to | θ _j|.

Meta task T will be proved in two kinds of situation below _iand T _jthe synthesis task T of synthesis _i,j={ W _i,j, d _i,j, θ _i,jtime window there is no redundancy time.

1)|W _i∩W _j|≤min(d _i,d _j)

When | W _i∩ W _j|≤min (d _i, d _j) time, Meta task T _ilate Start we _i-d _iwith Meta task T _jearliest finish time ws _j+ d _jbe included in generated time window.Therefore these two Meta task once can be observed imaging by satellite.Therefore, the shortest execution duration synthesizing task is (ws _j+ d _j)-(we _i-d _i).Therefore formula $d_{i,j}=\left\{\begin{array}{cc}{\mathrm{ws}}_j+d_j-({\mathrm{we}}_i-d_i),& \mathrm{if}|W_i\&cap;W_j|\&le;\min (d_i,d_j)\\ \max \{d_i,d_j\},& \mathrm{else}\end{array}\right.$ Set up.Correspondingly, the time window of the synthesis task of embodiment of the present invention synthesis is [(we _i-d _i), (ws _j+ d _j)].Therefore formula ${\mathrm{ws}}_{i,j}=\left\{\begin{array}{cc}{\mathrm{we}}_i-d_i,& \mathrm{if}|W_i\&cap;W_j|\&le;\min (d_i,d_j)\\ \min \{{\mathrm{ws}}_j,\max ({\mathrm{ws}}_i,{\mathrm{ws}}_j+d_j-d_i)\},& \mathrm{else}\end{array}\right.$ With ${\mathrm{we}}_{i,j}=\left\{\begin{array}{cc}{\mathrm{ws}}_j+d_j,& \mathrm{if}|W_i\&cap;W_j|\&le;\min (d_i,d_j)\\ \min ({\mathrm{we}}_i-d_i,{\mathrm{we}}_j-d_j)+\max \{d_i,d_j\},& \mathrm{else}\end{array}\right.$ Set up.

2)|W _i∩W _j|≥min(d _i,d _j)

As formula $\left\{\begin{array}{c}|W_{i,j}\&cap;W_i|\&GreaterEqual;d_i\\ |W_{i,j}\&cap;W_j|\&GreaterEqual;d_j\\ {\mathrm{we}}_{i,j}-{\mathrm{ws}}_{i,j}\&le;\mathrm{\&Delta;}{d}_s\\ d_{i,j}\&GreaterEqual;\max (d_i,d_j)\end{array}\right.$ Shown in, d _ij>=max (d _i, d _j).When | W _i∩ W _j|>=min (d _i, d _j) time, the actual common factor being less than two Meta task time windows of execution duration of one of both Meta task.Therefore, task T is synthesized _i,jthe shortest execution duration d _i,jequal max (d _i, d _j).And synthesize task T _i,jthe earliest start time of time window and the end time will depend on d the latest _i, d _jwith | W _i∩ W _j|.

Without loss of generality, d is supposed _i>=d _j.The common factor of time window is W _{i ∩ j}=[ws _{i ∩ j}, we _{i ∩ j}], (ws _{i ∩ j}for the start time that time window occurs simultaneously, we _{i ∩ j}end time for time window occurs simultaneously).As shown in Figure 5, black line frame represents the common factor of two time windows, and its start time is ws _{i ∩ j}, the end time is we _{i ∩ j}.The time window earliest start time of compact synthesis task should be max (ws _i, ws _j+ d _j-d _i), the end time is min (we the latest _i, we _j, we _{i ∩ j}-d _j+ d _i).

If two Meta task can synthesize, so they must be within the scope of the field angle of satellite sensor simultaneously.Namely the difference at the side-sway angle of two Meta task can not exceed the size of the field angle of sensor.So synthesize the side-sway angle then field angle of sensor and the side-sway angle decision of each Meta task thus of task.

Task T _iand T _jthe sufficient and necessary condition that can synthesize is | θ _i-θ _j|≤Δ θ _s(for ease of writing, replace Δ θ with Δ θ below _s), be described as follows:

The proof of adequacy is as follows:

If a side-sway angle θ _i,jif it can meet

${\mathrm{\&theta;}}_{i,j}\&Element;\left(\right[{\mathrm{\&theta;}}_i-\frac{\mathrm{\&Delta;\&theta;}}{2},{\mathrm{\&theta;}}_i+\frac{\mathrm{\&Delta;\&theta;}}{2}]\&cap;[{\mathrm{\&theta;}}_j-\frac{\mathrm{\&Delta;\&theta;}}{2},{\mathrm{\&theta;}}_j-\frac{\mathrm{\&Delta;\&theta;}}{2}\left]\right),$

So this side-sway angle θ _i,jfeasible.That is, with regard to side-sway angle, Meta task T _iand T _jcan synthesize.

A value at given side-sway angle due to | θ _i-θ _j|≤Δ θ, then-Δ θ≤θ _i-θ _j≤ Δ θ ,-Δ θ≤θ _j-θ _i≤ Δ θ, so

$\left\{\begin{array}{c}{\mathrm{\&theta;}}_{i,j}-({\mathrm{\&theta;}}_i-\frac{\mathrm{\&Delta;\&theta;}}{2})=\frac{{\mathrm{\&theta;}}_i+{\mathrm{\&theta;}}_j}{2}-{\mathrm{\&theta;}}_i+\frac{\mathrm{\&Delta;\&theta;}}{2}=\frac{{\mathrm{\&theta;}}_j-{\mathrm{\&theta;}}_i}{2}+\frac{\mathrm{\&Delta;\&theta;}}{2}\&GreaterEqual;-\frac{\mathrm{\&Delta;\&theta;}}{2}+\frac{\mathrm{\&Delta;\&theta;}}{2}=0\\ {\mathrm{\&theta;}}_{i,j}-({\mathrm{\&theta;}}_i+\frac{\mathrm{\&Delta;\&theta;}}{2})=\frac{{\mathrm{\&theta;}}_i+{\mathrm{\&theta;}}_j}{2}-{\mathrm{\&theta;}}_i-\frac{\mathrm{\&Delta;\&theta;}}{2}=\frac{{\mathrm{\&theta;}}_j-{\mathrm{\&theta;}}_i}{2}-\frac{\mathrm{\&Delta;\&theta;}}{2}\&le;\frac{\mathrm{\&Delta;\&theta;}}{2}-\frac{\mathrm{\&Delta;\&theta;}}{2}=0\end{array}\right..$

So ${\mathrm{\&theta;}}_{i,j}\&Element;[{\mathrm{\&theta;}}_i-\frac{\mathrm{\&Delta;\&theta;}}{2},{\mathrm{\&theta;}}_i+\frac{\mathrm{\&Delta;\&theta;}}{2}],$ In like manner, ${\mathrm{\&theta;}}_{i,j}\&Element;[{\mathrm{\&theta;}}_j-\frac{\mathrm{\&Delta;\&theta;}}{2},{\mathrm{\&theta;}}_j+\frac{\mathrm{\&Delta;\&theta;}}{2}].$

Therefore, ${\mathrm{\&theta;}}_{i,j}\&Element;\left(\right[{\mathrm{\&theta;}}_i-\frac{\mathrm{\&Delta;\&theta;}}{2},{\mathrm{\&theta;}}_i+\frac{\mathrm{\&Delta;\&theta;}}{2}]\&cap;[{\mathrm{\&theta;}}_j-\frac{\mathrm{\&Delta;\&theta;}}{2},{\mathrm{\&theta;}}_j-\frac{\mathrm{\&Delta;\&theta;}}{2}\left]\right).$

The proof of necessity is as follows:

If Meta task T _iand T _jcan synthesize, these two tasks must once have been observed, under so they must be in satellite scanning strip.Therefore the difference at the side-sway angle of these two Meta task must be less than satellite sensor field angle, namely | θ _i-θ _j|≤Δ θ.So necessary condition is set up.

To prove that the side-sway angle of synthesis task that the formula embodiment of the present invention is synthesized is the minimum angle in all feasible side-sway angles in two kinds of situation below.Without loss of generality, Meta task T is supposed _iside-sway angle be greater than T _jside-sway angle, namely | θ _i| >| θ _j|.

(1)θ _i≥0

If ${\mathrm{\&theta;}}_i-\frac{\mathrm{\&Delta;\&theta;}}{2}\&GreaterEqual;0,$ So ${\mathrm{\&theta;}}_i-\frac{\mathrm{\&Delta;\&theta;}}{2}-\frac{\mathrm{\&Delta;\&theta;}}{2}\&le;{\mathrm{\&theta;}}_i\&le;{\mathrm{\&theta;}}_i-\frac{\mathrm{\&Delta;\&theta;}}{2}+\frac{\mathrm{\&Delta;\&theta;}}{2}.$ Known | θ _i-θ _j|≤Δ θ, so ${\mathrm{\&theta;}}_i-\frac{\mathrm{\&Delta;\&theta;}}{2}-\frac{\mathrm{\&Delta;\&theta;}}{2}\&le;{\mathrm{\&theta;}}_j\&le;{\mathrm{\&theta;}}_i-\frac{\mathrm{\&Delta;\&theta;}}{2}+\frac{\mathrm{\&Delta;\&theta;}}{2}.$ So it is a feasible side-sway angle.

Assuming that the angle that existence one is less ${\mathrm{\&theta;}}^{\text{'}}<{\mathrm{\&theta;}}_i-\frac{\mathrm{\&Delta;\&theta;}}{2},$ So ${\mathrm{\&theta;}}^{\text{'}}+\frac{\mathrm{\&Delta;\&theta;}}{2}<{\mathrm{\&theta;}}_i-\frac{\mathrm{\&Delta;\&theta;}}{2}+\frac{\mathrm{\&Delta;\&theta;}}{2}={\mathrm{\&theta;}}_i,$ Now show Meta task T _inot in sensor field of view angular region.Therefore, it is the minimum side pivot angle of synthesis task.

If ${\mathrm{\&theta;}}_i-\frac{\mathrm{\&Delta;\&theta;}}{2}<0,$ So $0-\frac{\mathrm{\&Delta;\&theta;}}{2}\&le;{\mathrm{\&theta;}}_i\&le;0+\frac{\mathrm{\&Delta;\&theta;}}{2}.$ Known | θ _i|>=| θ _j|, there is θ _i> θ _j>-θ _i, then therefore, 0 is the minimum side pivot angle of synthesis task.

It can thus be appreciated that it is the minimum angle in all feasible side-sway angles.

(2)θ _i<0

If ${\mathrm{\&theta;}}_i+\frac{\mathrm{\&Delta;\&theta;}}{2}\&le;0,$ Then ${\mathrm{\&theta;}}_i+\frac{\mathrm{\&Delta;\&theta;}}{2}-\frac{\mathrm{\&Delta;\&theta;}}{2}\&le;{\mathrm{\&theta;}}_i\&le;{\mathrm{\&theta;}}_i+\frac{\mathrm{\&Delta;\&theta;}}{2}+\frac{\mathrm{\&Delta;\&theta;}}{2},$ Known again | θ _i-θ _j|≤Δ θ and | θ _i|>=| θ _j|, so θ _j-θ _i≤ Δ θ, then so it is a feasible side-sway angle.Assuming that the angle θ ' that existence one is less, then ${\mathrm{\&theta;}}_i+\frac{\mathrm{\&Delta;\&theta;}}{2}<{\mathrm{\&theta;}}^{\text{'}}<0,$ Can obtain ${\mathrm{\&theta;}}^{\text{'}}-\frac{\mathrm{\&Delta;\&theta;}}{2}>{\mathrm{\&theta;}}_i+\frac{\mathrm{\&Delta;\&theta;}}{2}-\frac{\mathrm{\&Delta;\&theta;}}{2}={\mathrm{\&theta;}}_i,$ Now show Meta task T _inot in sensor field of view angular region.Therefore, it is the minimum side pivot angle of synthesis task.

If ${\mathrm{\&theta;}}_i+\frac{\mathrm{\&Delta;\&theta;}}{2}>0,$ Then $0-\frac{\mathrm{\&Delta;\&theta;}}{2}\&le;{\mathrm{\&theta;}}_i\&le;0+\frac{\mathrm{\&Delta;\&theta;}}{2},$ By | θ _i|>=| θ _j| known θ _i≤ θ _j≤-θ _i, so therefore, 0 is the minimum side pivot angle of synthesis task.

Therefore, it is the minimum angle in all feasible side-sway angles.

As shown in Figure 6, the present embodiment discloses a kind of device of compound imaging satellite Meta task, comprising:

Acquiring unit 1, for obtain be in same imaging satellite sensor field angle within the scope of multiple Meta task T ₁, T ₂, T ₃..., T _n;

Middle task generation unit 2, for according to described multiple Meta task T ₁, T ₂, T ₃..., T _ngenerate the first middle task and the second middle task; The side-sway angle of described first middle task, the start time of time window, end time and the shortest execution duration are respectively θ _x, ws _x, we _xand d _x, the side-sway angle of described second middle task, the start time of time window, end time and the shortest execution duration are respectively θ _y, ws _y, we _yand d _y;

Synthesis task generation unit 3, for judging described θ _x, ws _x, we _xand d _x, and described θ _y, ws _y, we _yand d _ywhether meet

(ws _y+ d _y)-(we _x-d _x)≤Δ d _s(ws _x≤ ws _y) and | θ _x-θ _y|≤Δ θ _s

Or (ws _x+ d _x)-(we _y-d _y)≤Δ d _s(ws _y<ws _x) and | θ _x-θ _y|≤Δ θ _s,

Wherein, described Δ d _s, Δ θ _srepresent single imaging on time and the field angle of described imaging satellite s respectively,

If meet, then by described multiple Meta task T ₁, T ₂, T ₃..., T _nsynthesize synthesis task,

If meet

(ws _y+ d _y)-(we _x-d _x)≤Δ d _s(ws _x≤ ws _y) and | θ _x-θ _y|≤Δ θ _s,

The side-sway angle of described synthesis task is θ _x,y,

${\mathrm{\&theta;}}_{x,y}=\left\{\begin{array}{cc}\max \{{\mathrm{\&theta;}}_x-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \min \{{\mathrm{\&theta;}}_x+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x<0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \max \{{\mathrm{\&theta;}}_y-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\\ \min \{{\mathrm{\&theta;}}_y+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y<0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\end{array}\right.,$

The start time of the time window of described synthesis task is ws _x,y,

${\mathrm{ws}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{we}}_x-d_x,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min \{{\mathrm{ws}}_y,\max ({\mathrm{ws}}_x,{\mathrm{ws}}_y+d_y-d_x)\},& \mathrm{else}\end{array}\right.,$

The end time of the time window of described synthesis task is we _x,y,

${\mathrm{we}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_y+d_y,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min ({\mathrm{we}}_x-d_x,{\mathrm{we}}_y-d_y)+\max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

The shortest execution duration of described synthesis task is d _x,y,

$d_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_y+d_y-({\mathrm{we}}_x-d_x),& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

If meet

(ws _x+ d _x)-(we _y-d _y)≤Δ d _s(ws _y<ws _x) and | θ _x-θ _y|≤Δ θ _s,

The side-sway angle of described synthesis task is θ _x,y,

${\mathrm{\&theta;}}_{x,y}=\left\{\begin{array}{cc}\max \{{\mathrm{\&theta;}}_y-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_y\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_x\right|\\ \min \{{\mathrm{\&theta;}}_y+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y<0,\left|{\mathrm{\&theta;}}_y\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_x\right|\\ \max \{{\mathrm{\&theta;}}_x-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_x\right|>\left|{\mathrm{\&theta;}}_y\right|\\ \min \{{\mathrm{\&theta;}}_x+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x<0,\left|{\mathrm{\&theta;}}_x\right|>\left|{\mathrm{\&theta;}}_y\right|\end{array}\right.,$

The start time of the time window of described synthesis task is ws _x,y,

${\mathrm{ws}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{we}}_y-d_y,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min \{{\mathrm{ws}}_x,\max ({\mathrm{ws}}_y,{\mathrm{ws}}_x+d_x-d_y)\},& \mathrm{else}\end{array}\right.,$

The end time of the time window of described synthesis task is we _x,y,

${\mathrm{we}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_x+d_x,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min ({\mathrm{we}}_y-d_y,{\mathrm{we}}_x-d_x)+\max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

The shortest execution duration of described synthesis task is d _x,y,

$d_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_x+d_x-({\mathrm{we}}_y-d_{x}y),& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \max \{d_x,d_y\},& \mathrm{else}\end{array}\right..$

The device of the compound imaging satellite Meta task described in the embodiment of the present invention, the synthesis task side-sway angle that the synthetic method compared to routine being in the synthesis task of the multiple Meta task synthesis within the scope of the field angle of same imaging satellite sensor is synthesized is minimum, and time window does not have redundancy time, thus than the task synthetic method of routine, more task can be synthesized, and the side-sway angle of the synthesis task of synthesis is less, execution time is shorter, thus the start number of times of satellite borne sensor can be reduced, reduce the energy loss of satellite, thus can satellite resource be saved.

Alternatively, in another embodiment of the device of compound imaging satellite Meta task of the present invention, if n is greater than 2,

Described middle task generation unit, comprising:

First synthon unit, for by described multiple Meta task T ₁, T ₂, T ₃..., T _nsynthesize synthesis task T _{1, n-1},

Second synthon unit, for according to described synthesis task T _{1, n-1}with described Meta task T _ngenerate the first middle task and the second middle task;

Described θ _x=max (max (θ ₁, 0), max (θ ₂, 0) ... max (θ _n, 0)),

Described ${\mathrm{ws}}_x=\left\{\begin{array}{ccc}{\mathrm{ws}}_n& \mathrm{if}& {\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{ws}}_{1.n-1}& & \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_x=\left\{\begin{array}{ccc}{\mathrm{we}}_n& \mathrm{if}& {\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{we}}_{1.n-1}& & \mathrm{else}\end{array}\right.,$

Described $d_x=\left\{\begin{array}{ccc}{d}_n& \mathrm{if}& {\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ d_{1.n-1}& & \mathrm{else}\end{array}\right.,$

Described θ _y=min (min (θ ₁, 0), min (θ ₂, 0) ... min (θ _n, 0)),

Described ${\mathrm{ws}}_y=\left\{\begin{array}{ccc}{\mathrm{ws}}_{1.n-1}& \mathrm{if}& {\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{ws}}_n& & \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_y=\left\{\begin{array}{ccc}{\mathrm{we}}_{1.n-1}& \mathrm{if}& {\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{we}}_n& & \mathrm{else}\end{array}\right.,$

Described $d_y=\left\{\begin{array}{ccc}{d}_{1.n-1}& \mathrm{if}& {\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ d_n& & \mathrm{else}\end{array}\right.,$

Wherein, described θ _p(p ∈ (1,2 ..., n)) and be Meta task T _pside-sway angle, described ws _n, we _nand d _nbe respectively Meta task T _nstart time of time window, end time and the shortest execution duration, described ws _{1, n-1}, we _{1, n-1}and d _{1, n-1}be respectively described synthesis task T _{1, n-1}start time of time window, end time and the shortest execution duration.

Alternatively, in another embodiment of the device of compound imaging satellite Meta task of the present invention, if n is 2,

Described θ _x=max (max (θ ₁, 0), max (θ ₂, 0)),

Described ${\mathrm{ws}}_x=\left\{\begin{array}{ccc}{\mathrm{ws}}_2& \mathrm{if}& {\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{ws}}_1& & \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_x=\left\{\begin{array}{ccc}{\mathrm{we}}_2& \mathrm{if}& {\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{we}}_1& & \mathrm{else}\end{array}\right.,$

Described $d_x=\left\{\begin{array}{ccc}{d}_2& \mathrm{if}& {\mathrm{ws}}_1>{\mathrm{ws}}_2\\ d_1& & \mathrm{else}\end{array}\right.,$

Described θ _y=min (min (θ ₁, 0), min (θ ₂, 0)),

Described ${\mathrm{ws}}_y=\left\{\begin{array}{ccc}{\mathrm{ws}}_1& \mathrm{if}& {\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{ws}}_2& & \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_y=\left\{\begin{array}{ccc}{\mathrm{we}}_1& \mathrm{if}& {\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{we}}_2& & \mathrm{else}\end{array}\right.,$

Described $d_y=\left\{\begin{array}{ccc}{d}_1& \mathrm{if}& {\mathrm{ws}}_1>{\mathrm{ws}}_2\\ d_2& & \mathrm{else}\end{array}\right..$

Although describe embodiments of the present invention by reference to the accompanying drawings, but those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, such amendment and modification all fall into by within claims limited range.

Claims (6)

1. a method for compound imaging satellite Meta task, is characterized in that, comprising:

S1, obtains the multiple Meta task T be within the scope of the field angle of same imaging satellite sensor ₁, T ₂, T ₃..., T _n;

S2, according to described multiple Meta task T ₁, T ₂, T ₃..., T _ngenerate the first middle task and the second middle task; The side-sway angle of described first middle task, the start time of time window, end time and the shortest execution duration are respectively θ _x, ws _x, we _xand d _x, the side-sway angle of described second middle task, the start time of time window, end time and the shortest execution duration are respectively θ _y, ws _y, we _yand d _y;

S3, judges described θ _x, ws _x, we _xand d _x, and described θ _y, ws _y, we _yand d _ywhether meet

(ws _y+ d _y)-(we _x-d _x)≤Δ d _s(ws _x≤ ws _y) and | θ _x-θ _y|≤Δ θ _s

Or (ws _x+ d _x)-(we _y-d _y)≤Δ d _s(ws _y<ws _x) and | θ _x-θ _y|≤Δ θ _s,

Wherein, described Δ d _s, Δ θ _srepresent single imaging on time and the field angle of described imaging satellite s respectively,

If meet, then by described multiple Meta task T ₁, T ₂, T ₃..., T _nsynthesize synthesis task,

Wherein, if meet

(ws _y+ d _y)-(we _x-d _x)≤Δ d _s(ws _x≤ ws _y) and | θ _x-θ _y|≤Δ θ _s,

The side-sway angle of described synthesis task is θ _x,y,

${\mathrm{\&theta;}}_{x,y}=\left\{\begin{array}{cc}\max \{{\mathrm{\&theta;}}_x-\frac{{\mathrm{\&Delta;\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \min \{{\mathrm{\&theta;}}_x+\frac{{\mathrm{\&Delta;\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x<0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \max \{{\mathrm{\&theta;}}_y-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\\ \min \{{\mathrm{\&theta;}}_y+\frac{{\mathrm{\&Delta;\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y<0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\end{array}\right.,$

The start time of the time window of described synthesis task is ws _x,y,

${\mathrm{ws}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{we}}_x-d_x,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min \{{\mathrm{ws}}_y,\max ({\mathrm{ws}}_x,{\mathrm{ws}}_y+d_y-d_x)\},& \mathrm{else}\end{array}\right.,$

The end time of the time window of described synthesis task is we _x,y,

${\mathrm{we}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_y+d_y,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min ({\mathrm{we}}_x-d_x,{\mathrm{we}}_y-d_y)+\max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

The shortest execution duration of described synthesis task is d _x,y,

$d_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_y+d_y-({\mathrm{we}}_x-d_x),& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

Wherein, if meet

(ws _x+ d _x)-(we _y-d _y)≤Δ d _s(ws _y<ws _x) and | θ _x-θ _y|≤Δ θ _s,

The side-sway angle of described synthesis task is θ _x,y,

${\mathrm{\&theta;}}_{x,y}=\left\{\begin{array}{cc}\max \{{\mathrm{\&theta;}}_y-\frac{{\mathrm{\&Delta;\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_y\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_x\right|\\ \min \{{\mathrm{\&theta;}}_y+\frac{{\mathrm{\&Delta;\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y<0,\left|{\mathrm{\&theta;}}_y\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_x\right|\\ \max \{{\mathrm{\&theta;}}_x-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_x\right|>\left|{\mathrm{\&theta;}}_y\right|\\ \min \{{\mathrm{\&theta;}}_x+\frac{{\mathrm{\&Delta;\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x<0,\left|{\mathrm{\&theta;}}_x\right|>\left|{\mathrm{\&theta;}}_y\right|\end{array}\right.,$

The start time of the time window of described synthesis task is ws _x,y,

${\mathrm{ws}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{we}}_y-d_y,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min \{{\mathrm{ws}}_x,\max ({\mathrm{ws}}_y,{\mathrm{ws}}_x+d_x-d_y)\},& \mathrm{else}\end{array}\right.,$

The end time of the time window of described synthesis task is we _x,y,

${\mathrm{we}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_x+d_x,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min ({\mathrm{we}}_y-d_y,{\mathrm{we}}_x-d_x)+\max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

The shortest execution duration of described synthesis task is d _x,y,

$d_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_x+d_x-({\mathrm{we}}_y-d_y),& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \max \{d_x,d_y\},& \mathrm{else}\end{array}\right..$

2. the method for compound imaging satellite Meta task according to claim 1, is characterized in that, if n is greater than 2,

Described according to described multiple Meta task T ₁, T ₂, T ₃..., T _ngenerate the first middle task and the second middle task, comprising:

By described multiple Meta task T ₁, T ₂, T ₃..., T _nsynthesize synthesis task T _{1, n-1},

According to described synthesis task T _{1, n-1}with described Meta task T _ngenerate the first middle task and the second middle task;

Described θ _x=max (max (θ ₁, 0), max (θ ₂, 0) ... max (θ _n, 0)),

Described ${\mathrm{ws}}_x=\left\{\begin{array}{cc}{\mathrm{ws}}_n& \mathrm{if}{\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{ws}}_{1.n-1}& \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_x=\left\{\begin{array}{cc}{\mathrm{we}}_n& \mathrm{if}{\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{we}}_{1.n-1}& \mathrm{else}\end{array}\right.,$

Described $d_x=\left\{\begin{array}{cc}{d}_n& \mathrm{if}{\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ d_{1.n-1}& \mathrm{else}\end{array}\right.,$

Described θ _y=min (min (θ ₁, 0), min (θ ₂, 0) ... min (θ _n, 0)),

Described ${\mathrm{ws}}_y=\left\{\begin{array}{cc}{\mathrm{ws}}_{1.n-1}& \mathrm{if}{\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{ws}}_n& \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_y=\left\{\begin{array}{cc}{\mathrm{we}}_{1.n-1}& \mathrm{if}{\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{we}}_n& \mathrm{else}\end{array}\right.,$

Described $d_y=\left\{\begin{array}{cc}{d}_{1.n-1}& \mathrm{if}{\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ d_n& \mathrm{else}\end{array}\right.,$

Wherein, described θ _p(p ∈ (1,2 ..., n)) and be Meta task T _pside-sway angle, described ws _n, we _nand d _nbe respectively Meta task T _nstart time of time window, end time and the shortest execution duration, described ws _{1, n-1}, we _{1, n-1}and d _{1, n-1}be respectively described synthesis task T _{1, n-1}start time of time window, end time and the shortest execution duration.

3. the method for compound imaging satellite Meta task according to claim 1, is characterized in that, if n is 2,

Described θ _x=max (max (θ ₁, 0), max (θ ₂, 0)),

Described ${\mathrm{ws}}_x=\left\{\begin{array}{cc}{\mathrm{ws}}_2& \mathrm{if}{\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{ws}}_1& \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_x=\left\{\begin{array}{cc}{\mathrm{we}}_2& \mathrm{if}{\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{we}}_1& \mathrm{else}\end{array}\right.,$

Described $d_x=\left\{\begin{array}{cc}{d}_2& \mathrm{if}{\mathrm{ws}}_1>{\mathrm{ws}}_2\\ d_1& \mathrm{else}\end{array}\right.,$

Described θ _y=min (min (θ ₁, 0), min (θ ₂, 0)),

Described ${\mathrm{ws}}_y=\left\{\begin{array}{cc}{\mathrm{ws}}_1& \mathrm{if}{\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{ws}}_2& \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_y=\left\{\begin{array}{cc}{\mathrm{we}}_1& \mathrm{if}{\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{we}}_2& \mathrm{else}\end{array}\right.,$

Described $d_y=\left\{\begin{array}{cc}{d}_1& \mathrm{if}{\mathrm{ws}}_1>{\mathrm{ws}}_2\\ d_2& \mathrm{else}\end{array}\right..$

4. a device for compound imaging satellite Meta task, is characterized in that, comprising:

Acquiring unit, for obtain be in same imaging satellite sensor field angle within the scope of multiple Meta task T ₁, T ₂, T ₃..., T _n;

Middle task generation unit, for according to described multiple Meta task T ₁, T ₂, T ₃..., T _ngenerate the first middle task and the second middle task; The side-sway angle of described first middle task, the start time of time window, end time and the shortest execution duration are respectively θ _x, ws _x, we _xand d _x, the side-sway angle of described second middle task, the start time of time window, end time and the shortest execution duration are respectively θ _y, ws _y, we _yand d _y;

Synthesis task generation unit, for judging described θ _x, ws _x, we _xand d _x, and described θ _y, ws _y, we _yand d _ywhether meet

(ws _y+ d _y)-(we _x-d _x)≤Δ d _s(ws _x≤ ws _y) and | θ _x-θ _y|≤Δ θ _s

Or (ws _x+ d _x)-(we _y-d _y)≤Δ d _s(ws _y<ws _x) and | θ _x-θ _y|≤Δ θ _s,

Wherein, described Δ d _s, Δ θ _srepresent single imaging on time and the field angle of described imaging satellite s respectively,

If meet, then by described multiple Meta task T ₁, T ₂, T ₃..., T _nsynthesize synthesis task,

Wherein, if meet

(ws _y+ d _y)-(we _x-d _x)≤Δ d _s(ws _x≤ ws _y) and | θ _x-θ _y|≤Δ θ _s,

The side-sway angle of described synthesis task is θ _x,y,

${\mathrm{\&theta;}}_{x,y}=\left\{\begin{array}{cc}\max \{{\mathrm{\&theta;}}_x-\frac{{\mathrm{\&Delta;\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \min \{{\mathrm{\&theta;}}_x+\frac{{\mathrm{\&Delta;\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x<0,\left|{\mathrm{\&theta;}}_x\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_y\right|\\ \max \{{\mathrm{\&theta;}}_y-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\\ \min \{{\mathrm{\&theta;}}_y+\frac{{\mathrm{\&Delta;\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y<0,\left|{\mathrm{\&theta;}}_y\right|>\left|{\mathrm{\&theta;}}_x\right|\end{array}\right.,$

The start time of the time window of described synthesis task is ws _x,y,

${\mathrm{ws}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{we}}_x-d_x,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min \{{\mathrm{ws}}_y,\max ({\mathrm{ws}}_x,{\mathrm{ws}}_y+d_y-d_x)\},& \mathrm{else}\end{array}\right.,$

The end time of the time window of described synthesis task is we _x,y,

${\mathrm{we}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_y+d_y,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min ({\mathrm{we}}_x-d_x,{\mathrm{we}}_y-d_y)+\max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

The shortest execution duration of described synthesis task is d _x,y,

$d_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_y+d_y-({\mathrm{we}}_x-d_x),& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

Wherein, if meet

(ws _x+ d _x)-(we _y-d _y)≤Δ d _s(ws _y<ws _x) and | θ _x-θ _y|≤Δ θ _s,

The side-sway angle of described synthesis task is θ _x,y,

${\mathrm{\&theta;}}_{x,y}=\left\{\begin{array}{cc}\max \{{\mathrm{\&theta;}}_y-\frac{{\mathrm{\&Delta;\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_y\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_x\right|\\ \min \{{\mathrm{\&theta;}}_y+\frac{{\mathrm{\&Delta;\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_y<0,\left|{\mathrm{\&theta;}}_y\right|\&GreaterEqual;\left|{\mathrm{\&theta;}}_x\right|\\ \max \{{\mathrm{\&theta;}}_x-\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x\&GreaterEqual;0,\left|{\mathrm{\&theta;}}_x\right|>\left|{\mathrm{\&theta;}}_y\right|\\ \min \{{\mathrm{\&theta;}}_x+\frac{{\mathrm{\&Delta;\&theta;}}_s}{2},0\},& \mathrm{if}{\mathrm{\&theta;}}_x<0,\left|{\mathrm{\&theta;}}_x\right|>\left|{\mathrm{\&theta;}}_y\right|\end{array}\right.,$

The start time of the time window of described synthesis task is ws _x,y,

${\mathrm{ws}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{we}}_y-d_y,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min \{{\mathrm{ws}}_x,\max ({\mathrm{ws}}_y,{\mathrm{ws}}_x+d_x-d_y)\},& \mathrm{else}\end{array}\right.,$

The end time of the time window of described synthesis task is we _x,y,

${\mathrm{we}}_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_x+d_x,& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \min ({\mathrm{we}}_y-d_y,{\mathrm{we}}_x-d_x)+\max \{d_x,d_y\},& \mathrm{else}\end{array}\right.,$

The shortest execution duration of described synthesis task is d _x,y,

$d_{x,y}=\left\{\begin{array}{cc}{\mathrm{ws}}_x+d_x-({\mathrm{we}}_y-d_y),& \mathrm{if}|W_x\&cap;W_y|\&le;\min (d_x,d_y)\\ \max \{d_x,d_y\},& \mathrm{else}\end{array}\right..$

5. the device of compound imaging satellite Meta task according to claim 4, is characterized in that, if n is greater than 2,

Described middle task generation unit, comprising:

First synthon unit, for by described multiple Meta task T ₁, T ₂, T ₃..., T _nsynthesize synthesis task T _{1, n-1},

Second synthon unit, for according to described synthesis task T _{1, n-1}with described Meta task T _ngenerate the first middle task and the second middle task;

Described θ _x=max (max (θ ₁, 0), max (θ ₂, 0) ... max (θ _n, 0)),

Described ${\mathrm{ws}}_x=\left\{\begin{array}{cc}{\mathrm{ws}}_n& \mathrm{if}{\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{ws}}_{1.n-1}& \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_x=\left\{\begin{array}{cc}{\mathrm{we}}_n& \mathrm{if}{\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{we}}_{1.n-1}& \mathrm{else}\end{array}\right.,$

Described $d_x=\left\{\begin{array}{cc}{d}_n& \mathrm{if}{\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ d_{1.n-1}& \mathrm{else}\end{array}\right.,$

Described θ _y=min (min (θ ₁, 0), min (θ ₂, 0) ... min (θ _n, 0)),

Described ${\mathrm{ws}}_y=\left\{\begin{array}{cc}{\mathrm{ws}}_{1.n-1}& \mathrm{if}{\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{ws}}_n& \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_y=\left\{\begin{array}{cc}{\mathrm{we}}_{1.n-1}& \mathrm{if}{\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ {\mathrm{we}}_n& \mathrm{else}\end{array}\right.,$

Described $d_y=\left\{\begin{array}{cc}{d}_{1.n-1}& \mathrm{if}{\mathrm{ws}}_{1.n-1}>{\mathrm{ws}}_n\\ d_n& \mathrm{else}\end{array}\right.,$

Wherein, described θ _p(p ∈ (1,2 ..., n)) and be Meta task T _pside-sway angle, described ws _n, we _nand d _nbe respectively Meta task T _nstart time of time window, end time and the shortest execution duration, described ws _{1, n-1}, we _{1, n-1}and d _{1, n-1}be respectively described synthesis task T _{1, n-1}start time of time window, end time and the shortest execution duration.

6. the device of compound imaging satellite Meta task according to claim 4, is characterized in that, if n is 2,

Described θ _x=max (max (θ ₁, 0), max (θ ₂, 0)),

Described ${\mathrm{ws}}_x=\left\{\begin{array}{cc}{\mathrm{ws}}_2& \mathrm{if}{\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{ws}}_1& \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_x=\left\{\begin{array}{cc}{\mathrm{we}}_2& \mathrm{if}{\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{we}}_1& \mathrm{else}\end{array}\right.,$

Described $d_x=\left\{\begin{array}{cc}{d}_2& \mathrm{if}{\mathrm{ws}}_1>{\mathrm{ws}}_2\\ d_1& \mathrm{else}\end{array}\right.,$

Described θ _y=min (min (θ ₁, 0), min (θ ₂, 0)),

Described ${\mathrm{ws}}_y=\left\{\begin{array}{cc}{\mathrm{ws}}_1& \mathrm{if}{\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{ws}}_2& \mathrm{else}\end{array}\right.,$

Described ${\mathrm{we}}_y=\left\{\begin{array}{cc}{\mathrm{we}}_1& \mathrm{if}{\mathrm{ws}}_1>{\mathrm{ws}}_2\\ {\mathrm{we}}_2& \mathrm{else}\end{array}\right.,$

Described $d_y=\left\{\begin{array}{cc}{d}_1& \mathrm{if}{\mathrm{ws}}_1>{\mathrm{ws}}_2\\ d_2& \mathrm{else}\end{array}\right..$