CN205120131U - Linear array infrared earth sensor electricity signal generator means - Google Patents

Abstract

The utility model discloses a linear array infrared earth sensor electricity signal generator means, the computer passes through A, B, C, D passageway during the position end value passes through serial ports driver injection control ware in the device, and the controller passes through the position end value with A, B, C, D passageway and converts DA setting parameters to, carries out digital analog conversion through write operation control DA converter, and the simulation produces the required signal of telecommunication of linear array infrared earth sensor. The gesture simulation problem that linear array infrared earth sensor was applied to different tracks, different mode has effectively been solved to this patent, provides a linear array infrared earth sensor's detection means, has ensured linear array infrared earth sensor's electrical performance test, provides the condition for all kinds of tests and emulation.

Description

Linear array infrared earth sensor electric signal generation device

Technical field

This patent relates to the testing apparatus of spaceborne infrared earth sensor.Be specifically related to a kind of linear array infrared earth sensor electric signal generation device, it is applicable to linear array infrared earth sensor detection means, the generation of Novel electric driving source.

Background technology

Infrared earth sensor, the attitude of satellite optical sensor based on earth sensitive for infrared radiation principle, can be used for spacecraft relative to the pitching of the local vertical line of the earth, roll attitude angle signal measurement, original state time spacecraft to the earth catch and steady-state operation time spacecraft gesture stability.

According to infrared earth sensor inside whether containing mechanical scanning mechanism, can be divided into scan-type and static two classes: wherein scan-type can be divided into again conical scanning formula (single circular cone, double cone) and oscillatory scanning formula two kinds, static state is then divided into linear array and face battle array two kinds.

Wherein, in linear array infrared earth sensor, detector is positioned on the focal plane of optical system, belongs to gazing type structure.When spacecraft runs on earth overhead, observe terrestrial time from spacecraft, obtain the disk that the average bright temperature be equivalent in 4K cold-scarce scape is about 220K ~ 240K, the edge of disk is called Horizon circle.When spacecraft runs on earth overhead, infrared earth sensor detects the earth infrared energy of 14 μm ~ 16.25 mu m wavebands in 4 orientation of Horizon circle by linear array infrared eye, determine the azimuth position of the corresponding Horizon circle of linear array infrared eye 4 points, according between geometric relationship, realize measurement to the attitude of satellite, obtain spacecraft relative to the angle of pitch of earth local vertical and roll angle.

At present, China have developed a Novel wire array infrared earth sensor and adopts modular design, four probes (optical system and detector composition is arranged by " X " structural symmetry, detector is positioned in optical system focal plane), the axis of rolling is consistent with celestial body heading, and pitch axis is vertical and orbital plane.A, B, C, D tetra-probe and the axis of rolling and pitch axis distribution at 45 °, adjacent two probe optical axis included angles are 90 °.This linear array infrared earth sensor has following characteristics: (1) precision is less than 0.1 ° (3 σ); (2) the variable aircraft of track can be adapted to; (3) different working modes can be adapted to; (4) attitude optimum condition scope can reach ± 20 ° (single shaft); (5) quality is light, volume is little, low in energy consumption.

Because of infrared earth sensor in-orbit object of observation be the earth, demonstration test directly cannot be carried out in ground.Normal, proper use of in order to what ensure in-orbit, ground in the face of infrared earth sensor carry out performance test and semi physical, full physical simulation is inevitable.Existing means mainly contain two kinds of forms, the earth simulator for earth (analog optical signal improves light excitation source) of design specialized and unit test equipment (analog electrical signal provides electric excitation source).Although the similarity of earth simulator for earth analog optical signal is higher, test coverage is larger, and its volume is large, use limitation is large, and more occasion still adopts unit test equipment to test.This electric signal just requiring unit test equipment to provide can possess good performance, mates the test of corresponding infrared earth sensor and uses needs.

Existing to electric signal source performance parameter and deviation requirement as follows: the designed path scope that infrared earth sensor is measured can be covered, under wild trajectory, electric excitation signal attitude scope all can cover infrared earth sensor measurement range, also meet the various mode of operation such as 4/4,3/4,2/4 simultaneously; Attitude Simulation precision: be less than 0.1 °; Each passage consistency: be not more than 5%; The renewal response time is not more than infrared earth sensor and resolves frequency.

Summary of the invention

The object of this patent is to provide a kind of linear array infrared earth sensor electric signal generation device, mates the performance test of corresponding infrared earth sensor, semi-physical simulation etc., ensures infrared earth sensor in-orbit normal, proper use of.

Based on the analogy method of linear array infrared earth sensor electric signal generation device, it is characterized in that comprising the following steps:

(1), obtain and pass through arbitrarily position X, its value is n+x, n be its integral part, and x be its fraction part, and the scope of X is from 0 to N, does not contain the Arbitrary Digit of N, and wherein N is the first number of linear array infrared earth sensor detector, its value be greater than 6 integer;

(2) clock signal, according to linear array infrared earth sensor provided, its value is t, t is 0 integer arriving N-1, and passes through position n+x, and controller calculates D/A parameters value according to following situation and controls to export, and wherein D/A inverting reference parameter value is k ₀, scope is 0 to 2 ^winteger, w is the precision figure place of D/A conversion, and D/A transition amplitude parameter value is k, and scope is 0 to being not more than integer:

As t < n-2, D/A parameters value is k ₀; As t=n-2, D/A parameters value is for being not more than k ₀the maximum integer of+k-kx; As t=n-1, D/A parameters value is for being not more than k ₀the maximum integer of+2k-kx; As t > n-1, D/A parameters value is for being not more than k ₀the maximum integer of+2k;

(3), by step (1) and (2), to A channel successively from 0 to N, spacing value is that position X is passed through in 0.1 setting, and by the injecting electronic signal linear array infrared earth sensor of modulating output, what obtain that this passage under these settings resolves by linear array infrared earth sensor passes through position, and its value is a _x, and calculating the deviation of itself and settings, 10N+1 group altogether, calculates average a devious _c;

From a _c-0.5 to a _c+ 0.5, spacing value is 0.01 value a successively _s, calculate meet with the minimum a of square mean devious _sbe A channel adaptability corrected parameter, its value is △ a;

(4), by step (3), obtain B, C, D channel adaptation corrected parameter successively, its value correspondence is followed successively by △ b, △ c, △ d;

(5), under any orbit altitude, according to formula, calculate zero attitude and pass through the theoretical value L of position, its value is l, and wherein h is the orbit altitude of linear array infrared earth sensor work, the field angle of unit to be km, θ the be each pixel of earth sensor, H ₀for the nominal track height of linear array infrared earth sensor design, unit is km;

(6), according to the track Zero positioning table of linear array infrared earth sensor carry out by the following method, obtain when theoretical value is l, A, B, C, D passage passes through the value a of location position zero-bit ₀, b ₀, c ₀, d ₀; The content of the track Zero positioning table of linear array infrared earth sensor is that the A channel that different theories value L is corresponding passes through location position zero-bit A ₀, channel B passes through location position zero-bit B ₀, C-channel passes through location position zero-bit C ₀location position zero-bit D is passed through with D passage ₀:

If the l obtained by step (5) can look in the table, then direct from table obtain;

If the l obtained by step (5) can not look in table, then choose the minimum set of data being not more than l, theoretical value L and A, B, C, D passage of these group data pass through location position zero-bit A ₀, B ₀, C ₀, D ₀value be designated as l respectively ₁, a ₁, b ₁, c ₁, d ₁, and being not less than the maximum group of data of l, theoretical value L and A, B, C, D passage of these group data pass through location position zero-bit A ₀, B ₀, C ₀, D ₀value be designated as l respectively ₂, a ₂, b ₂, c ₂, d ₂.As follows, acquisition is calculated:

$a_0=a_2+\frac{l-l_2}{l_1-l_2}(a_1-a_2),b_0=b_2+\frac{l-l_2}{l_1-l_2}(b_1-b_2),$

$c_0=c_2+\frac{l-l_2}{l_1-l_2}(c_1-c_2),d_0=d_2+\frac{l-l_2}{l_1-l_2}(d_1-d_2);$

(7), by following formula, calculate A, B, C, D passage and pass through position original value, its value correspondence is followed successively by a _y, b _y, c _y, d _y:

$a_y=a_0+(\frac{\sqrt{2}}{2}p/Kp-\frac{\sqrt{2}}{2}r/Kr)/\mathrm{\&theta;},b_y=b_0+(-\frac{\sqrt{2}}{2}p/Kp-\frac{\sqrt{2}}{2}r/Kr)/\mathrm{\&theta;}$

$c_y=c_0+(-\frac{\sqrt{2}}{2}p/Kp+\frac{\sqrt{2}}{2}r/Kr)/\mathrm{\&theta;},d_y=d_0+(\frac{\sqrt{2}}{2}p/Kp+\frac{\sqrt{2}}{2}r/Kr)/\mathrm{\&theta;}$

Wherein p, r correspondence respectively is the attitude of satellite angle of pitch, roll angle, K _p, K _rcorrespondence respectively is linear array infrared earth sensor pitch axis, the linear calibration parameter of the axis of rolling;

(8), be calculated as follows A, B, C, D passage and pass through position adaptive correction value, its value correspondence is followed successively by a _j, b _j, c _j, d _j:

a _j＝a _y+△a，b _j＝b _y+△b，c _j＝c _y+△c，d _j＝d _y+△d；

(9), according to linear array infrared earth sensor A channel radiometric correction formula f _acarry out inverse, wherein:

f _A(x)＝a ₁x ²+a ₂x+a ₃+b ₁*sin(2π(x-b ₂))

A in formula ₁, a ₂, a ₃be respectively the quadratic term coefficient of quadratic fit, Monomial coefficient and constant term coefficient, b ₁, b ₂be respectively the range coefficient of sine function matching, phase coefficient;

From a _j-0.5 to a _j+ 0.5, spacing value is 0.001 value I successively _a, meet at first | f _a(I _a+ 0.5)-I _a| the I of≤0.01 _abe A channel and pass through position radiometric correction value, its value is a _f;

(10), by step (9), obtain B, C, D passage successively and pass through position radiometric correction value, its value correspondence is followed successively by b _f, c _f, d _f;

(11) if a _f, b _f, c _f, d _fbe greater than 0 when being less than N, be modified to 0; If when not needing certain channel data under the mode of operation of current Earth sensor, then this passage is modified to 0; Finally obtain A, B, C, D passage and pass through position end value A _o, B _o, C _o, D _o;

(12) A, B, C, D passage, obtained according to step (10) passes through position end value A _o, B _o, C _o, D _o, carry out D/A conversion by step (1) and (2) corresponding A, B, C, D tetra-paths.

Described linear array infrared earth sensor electric signal generation device comprises computing machine, serial driver, controller and four road D/A converters, wherein:

Described serial driver adopts 232 serial driver MAX232;

Described controller adopts microcontroller, FPGA or processor;

Four described road D/A converters, precision figure place is 8,12 or 16, and amplitude output signal scope is-2.5V ~ 2.5V, and switching rate is not less than the frequency of clock signal T;

A, B, C, D passage is passed through position end value by serial driver injecting controller by computing machine, A, B, C, D passage is passed through position end value and converts D/A parameters to by controller, control D/A converter by write operation and carry out digital-to-analog conversion, simulation produces the electric signal needed for linear array infrared earth sensor.

The advantage of this patent:

This patent efficiently solves the detection means that linear array infrared earth sensor is applied to different track, the attitude-simulating problem of different working modes provides a kind of linear array infrared earth sensor, ensure the electric performance test of linear array infrared earth sensor, for all kinds of testing and simulation provides condition.

Accompanying drawing explanation

Fig. 1 is apparatus structure schematic diagram.

Fig. 2 is bulk treatment method flow diagram.

Embodiment

According to method described in this patent, the linear array infrared earth sensor of certain model aircraft supporting devises a electric signal generation device, has carried out replication experiment, and has carried out error evaluation in conjunction with infrared earth sensor.

In replication experiment, the value of each parameter is as follows:

Label in literary composition and in formula	Value or parameter
		N	16 yuan
θ	2°
		H 0	500km
D/A switching signal amplitude	-2.5V～2.5V
		D/A inversion frequency	32Hz
D/A converter precision	8
		k0	40
k	80
		Theoretical Design precision	0.038°

The quick test result in ground:

Test item	Test value
		Precision 3 δ	＜0.05
Angle measurement deviation (< 5 °)	＜0.05°
		Attitude-simulating scope	The quick measurable angle range of mulched ground

Calibrating parameters is as follows:

△a＝0.1330，△b＝0.1430，△c＝0.1300，△d＝0.0960。

Desirably quick parameter is as follows:

1. four-way radiometric correction formula

f _A＝0.0030x ²+0.9561x+0.1343-0.070sin(2π(x-0.42))；

f _B＝0.0018x ²+0.9739x+0.0772-0.070sin(2π(x-0.42))；

f _C＝0.0028x ²+0.9598x+0.1212-0.070sin(2π(x-0.42))；

f _D＝0.0021x ²+0.9697x+0.0924-0.078sin(2π(x-0.42))。

2. track Zero positioning table

3. pitch axis, the linear calibration parameter of the axis of rolling

K _p＝1.038，K _r＝1.038。

Claims (1)

1. a linear array infrared earth sensor electric signal generation device, comprises computing machine, serial driver, controller and four road D/A converters, it is characterized in that:

Described serial driver adopts 232 serial driver MAX232;

Described controller adopts microcontroller, FPGA or processor;

Four described road D/A converters, precision figure place is 8,12 or 16, and amplitude output signal scope is-2.5V ~ 2.5V, and switching rate is not less than the frequency of clock signal T;

A, B, C, D passage is passed through position end value by serial driver injecting controller by computing machine, A, B, C, D passage is passed through position end value and converts D/A parameters to by controller, control D/A converter by write operation and carry out digital-to-analog conversion, simulation produces the electric signal needed for linear array infrared earth sensor.