RU2535247C1 - Method and device to measure angular coordinates of stars - Google Patents

Abstract

FIELD: physics, optics.

SUBSTANCE: invention relates to optic-electronic instrument making and may be used in optic-electronic instruments (OEI) for celestial orientation, comprising a matrix photodetector with charge accumulation. The solution consists in projection of a stellar sky area onto a photosensitive site of a photodetector via an image lens in three or more spectral ranges and calibration marks with varied exposition time, identification of stellar objects images in all spectral ranges and generation of a multispectral image of stellar objects by selection for each stellar object of an image of that spectral range, the average value of amplitude in which is highest, measurement of linear coordinates of star image centres and calibration marks and recount of linear coordinates of star image centres into angular coordinates o stars in a basic instrument system of coordinates with account of results of measurements of linear coordinates of calibration mark image centres.

EFFECT: increased accuracy of measurement of angular coordinates of stars due to increased signal/noise ratio by processing of star images in separate spectral ranges.

5 cl, 1 dwg

Description

The invention relates to the field of navigation and instruments for space navigation G01C 21/24 and, at the same time, to devices for measuring devices characterized by optical measuring instruments for measuring angles G01B 11/26. It can be used in optoelectronic devices (OEDs) for orienting in stars containing an array photodetector with charge accumulation.

A known method of measuring the angular coordinates of stars with an optical-electronic device for orienting by stars by projecting on a photosensitive surface of the receiver an image of a portion of the starry sky, measuring the linear coordinates of the images of stars on this surface, projecting on the same photosensitive surface special calibration marks that are rigidly connected to the base instrument coordinate system and having previously known angular coordinates in it, measuring the linear coordinates of these marks and subsequent recounting is the linear coordinates of stars in their angular position taking into account the results of measurements of the calibration markers linear coordinates [1, 2]. In this case, the basic instrument coordinate system is implemented by the structural elements of the instrument, which eliminates the influence of microdeformations of insufficiently stable structural elements of the instrument (for example, a photodetector) on the measurement accuracy. The described method has the following disadvantages: when projecting calibration marks on the receiver, it is necessary to block the optical star channel using the shutter, which increases the measurement time, and the presence of an electromechanical or optical shutter in the device worsens the overall mass characteristics of the device and reduces reliability. The accuracy characteristics of the instrument, determined by the signal from the stars and the noise level, depend on the emission spectrum of stars and vary significantly for different stellar objects.

Another analogue of the invention is a method [3], which includes projecting through a lens a stellar channel onto a photosensitive surface of a matrix receiver of an image of a portion of the starry sky, measuring the linear coordinates of the image of stars on this surface, then projecting onto the same surface through a stellar channel lens special calibration marks formed by the collimator optical channel of the standard and rigidly connected with the base instrument coordinate system; precise angle measurement performed in advance 's coordinate the calibration markers in the base of the instrument coordinate system the coordinates of the measurement of linear marks and the calibration coordinates conversion of linear into angular coordinates star base coordinate system based on the results of measurements of linear coordinates the calibration marks. This method has several disadvantages: when projecting calibration marks on the receiver, it is also necessary to block the optical star channel using the shutter, which increases the measurement time, and the presence of an electromechanical or optical shutter in the device worsens the overall dimensions of the device and reduces reliability. The use of amplitude selection of the signal of calibration marks requires an extension of the dynamic range of the entire photoelectron path, which in many cases is difficult due to the required large dynamic range for working sources - stars. The accuracy characteristics of the instrument, determined by the signal from the stars and the noise level, depend on the emission spectrum of stars and vary significantly for different stellar objects.

Closest to the invention is a method and apparatus for measuring the angular coordinates of stars [4]. The method includes projecting onto a photosensitive area of the photodetector through the lens an image of a portion of the starry sky and calibration marks, measuring the linear coordinates of the centers of the image of stars and the linear coordinates of the centers of the images of the calibration marks on the photosensitive area of the photodetector, and recalculating the linear coordinates of the centers of the image of the stars in the angular coordinates of the stars in the base instrument coordinate system taking into account the results of measurements of the linear coordinates of the centers of the images of the calibration marks. When projecting calibration marks and measuring the linear coordinates of the centers of their images, the signal accumulation time in the photodetector is set to K times less than when working with stars. The magnitude of the reduction factor for the accumulation time K and the illumination of the images of the calibration marks are chosen so that the signal at the output of the photodetector from the brightest working star is less than the signal from the calibration marks. Additionally, amplitude selection of calibration marks signals is performed according to the criterion for exceeding a pre-selected threshold level, the device for measuring the angular coordinates of stars contains a lens hood, a geometric reference channel (CGE), a lens, a photodetector array with charge accumulation, a photosensitive area of which is located in the focal plane of the lens, an ADC unit, a unit for forming a variable exposure time, a unit for controlling the operation of the matrix photodetector, and a unit for digital processing and control. The digital processing and control unit includes an amplitude signal selector, a unit for extracting useful signals from interference, a star recognition unit, a synchronization unit, and a computing device for measuring the angular coordinates of stars based on the coordinates of the CGE calibration marks. The considered method and device have a drawback: the accuracy of measuring the angular coordinates of stars varies significantly for different stellar objects, which leads to a decrease in the overall accuracy of measuring the angular coordinates of stars and the associated accuracy of orientation with respect to stars.

The purpose of the invention is to increase the overall accuracy of measuring the angular coordinates of stars.

This goal is achieved in that the image formation of a portion of the starry sky on the photosensitive area of the matrix photodetector is carried out in three or more (M) spectral ranges with a change in the exposure mode of the matrix receiver for each range. In this case, the exposure time of the matrix photodetector in the spectral ranges varies inversely with the band of this spectral range, and the linear coordinates of the centers of the images of stars are measured in each spectral range with the subsequent selection of those coordinates in which the corresponding stellar object has a maximum average intensity value. This choice provides the best measurement conditions among all spectral ranges, and therefore increases the overall accuracy of measuring the angular coordinates of stars and the accuracy of the meter as a whole.

The proposed method for measuring the angular coordinates of stars using an angle measuring star device based on an array photodetector with charge accumulation includes:

- projection onto the photosensitive surface of the matrix photodetector with the accumulation of charge through the image lens of a portion of the starry sky;

- measuring the linear coordinates of the centers of the images of stars on the photosensitive area of the receiver;

- projection onto the photosensitive surface of the matrix photodetector with the accumulation of charge through the lens of special calibration marks formed by the collimator of the geometric standard channel and rigidly connected to the base instrument coordinate system implemented by the device’s structural elements, and when projecting calibration marks, the signal accumulation time in the receiver is set to K times less than when working with stars, and the magnitude of the decrease in the accumulation time K and the illumination of images are calib rational marks are pre-selected so that the signal at the output of the receiver from the brightest working star is less than the signal from the calibration marks;

- amplitude selection of the signals of the calibration marks by the criterion for exceeding a pre-selected threshold level that exceeds the signal from the brightest star, and measuring the linear coordinates of the centers of the images of the calibration marks on the photosensitive surface of the matrix photodetector with the accumulation of charge;

- recalculation of the linear coordinates of the centers of the image of stars in the angular coordinates of the stars in the base instrument coordinate system, taking into account the results of measurements of the linear coordinates of the centers of the images of the calibration marks at their known angular coordinates.

Moreover, to increase the overall accuracy of measuring the angular coordinates of stars:

- an image of a portion of the starry sky is formed on the photosensitive area of the matrix photodetector with the accumulation of charge in three or more (M) spectral ranges by pre-filtering the light flux from the selected portion of the starry sky in the filter system, and the exposure time in each spectral range is inversely proportional to the relative width of this spectral range;

- from the obtained range images of the starry sky, images of stellar objects in all spectral ranges are extracted and multispectral images of stellar objects are formed from them by selecting for each stellar object images of that spectral range, the average amplitude in which is the largest among all range images of a given star;

- as the linear coordinates of the centers of images of stars, the coordinates of the centers of multispectral images of stars are selected.

The proposed device for measuring the angular coordinates of stars contains: a hood, a channel of a geometric standard (CGE), made in the form of a collimator unit with a illuminator, forming images of calibration marks, and an input element that implements the image of calibration marks in the lens, objective, photodetector matrix with charge accumulation, a photosensitive pad which is located in the focal plane of the lens, a control unit for the operation of the matrix photodetector with the accumulation of charge, the outputs of which are connected to control inputs of the matrix photodetector with charge accumulation, a unit for forming a variable exposure time, the output of which is connected to the exposure input of the matrix photodetector with charge storage, an analog processing and analog-to-digital conversion (ADC) block, the input of which is connected to the output of the photodetector matrix with charge storage, block digital processing and control, the input of which is connected to the output of the block of analog processing and analog-to-digital conversion, the first output is connected to the input of the collimator unit with a illuminator, the second output is connected to the input of the matrix photodetector operation control unit with charge accumulation, the third output is connected to the input of the variable exposure time generation unit, and the fourth output is the output of the device for measuring the angular coordinates of stars, the digital processing and control unit includes: a signal selector, the input of which is an input of a digital processing and control unit, a block for extracting useful signals from interference, and a star recognition unit, ph the leader of the switching commands for the exposure of the matrix photodetector, the output of which is the third output of the digital processing and control unit, a computing device for determining the angular coordinates of the stars, the output of which is the fourth output of the digital processing and control unit, and the synchronization unit, the first and second outputs of which are the first and second, respectively the outputs of the digital processing and control unit, its third output is connected to the input of the generator of commands for switching the exposure of the matrix photodetector nick, and a fourth output connected to the input of the synchronization of the computing device determining the angular coordinates of the stars. In the device for measuring the angular coordinates of stars, a block of switchable filters is included, included between the hood and the input element and forming in the sequence of the hood, a block of switchable filters, an input element, the lens is an optical image path, the manager of the switchable filter block, the output of which is connected to the control input of the block switchable filters, and a fifth output is added to the digital processing and control unit, which is the third output of the synchronization unit and connected to the input of the manager of the switchable filter block, the multispectral image forming unit of the stars, the input of which is connected to the output of the star recognition unit, the output is connected to the input of the computing device for determining the angular coordinates of stars, and the synchronization input is connected to the fourth output of the synchronization unit.

The proposed measurement method is generally implemented as follows. When designing a device, its construction includes the possibility of projecting special calibration marks that are rigidly connected to the base instrument coordinate system and included as necessary on the photosensitive area of the receiver. In the manufacture of the device, the angular coordinates of these marks in the base coordinate system are measured with high accuracy and are recorded in the memory of the device’s computing device. When the instrument is operated on stars, a portion of the starry sky is projected through the lens of the stellar channel through the lens of the stellar channel in three or more spectral ranges by switching the filters and simultaneously changing the exposure time in inverse proportion to the relative width of the spectrum of the signal passing through this filter. For each image of a stellar object, a decision is made on the choice of the spectral range of its representation in the generated multispectral image of stars. The choice of the spectral range of representation of the image of a star is carried out as a result of comparison and the choice of the maximum of the average values for the image elements of the star in each spectral range. Based on the results of this choice, a multispectral image of stellar objects is formed. The computing device for determining the angular coordinates of the stars measures the linear coordinates of the images of stars on the sensitive area of the matrix receiver from the obtained multispectral image of stellar objects. Next, calibration marks are turned on and their image is projected onto the same photosensitive area. At the same time, the exposure time of the matrix receiver changes so that the signal of the calibration marks exceeds the marks from the image of the brightest stars. When processing the signal from the calibration marks in the electronic path of the device, their amplitude selection is performed based on the threshold being exceeded, the value of which is greater than the signal from bright stars. Subject to these conditions, the linear coordinates of the calibration marks are measured on the working platform of the matrix receiver. Then, the measured linear coordinates of the stars obtained from the multispectral image are recalculated into the angular coordinates in the base coordinate system, taking into account the results of measuring the linear coordinates of the calibration marks and the results of measurements of the angular coordinates of these marks made in advance.

Figure 1 presents the structural diagram of a device for measuring the angular coordinates of stars that implements the proposed method.

A device for measuring the angular coordinates of stars contains: a hood 1; the manager of the block of switched light filters 2; block of switched light filters 3; lens 4; a geometric reference channel (CGE), made in the form of a collimator unit with a illuminator 6, forming images of the calibration marks, and an input element 5, made, for example, in the form of a mirror-prism unit, which implements the image of the calibration marks in the lens, technically the illuminator of the collimator unit can be made in the form of at least one LED; unit for forming a variable exposure time 7; array photodetector with charge accumulation 8; the control unit of the operation of the matrix photodetector with the accumulation of charge 9; block analog processing and analog-to-digital conversion 10; a digital processing and control unit 11, including a driver of exposure switching commands 12; amplitude signal selector 13; a unit for extracting useful signals from interference 14, a star recognition unit 15, a synchronization unit 16; block for forming a multispectral image of stars 17, a computing unit for determining the angular coordinates of stars 18.

Technically, in the multispectral image forming unit of the stars 17 and in the computing unit for determining the angular coordinates of the stars 18, a memory device is usually included, which is also implemented in the form of non-volatile memory or in the form of any other type of memory.

The variable exposure time generation unit 7 is introduced specifically for generating one of the M + 1 photodetector exposure times corresponding to the M spectral ranges and the exposure of the calibration marks by commands of the corresponding exposure switching command generator 12 from the digital processing and control unit 11.

A device for measuring the angular coordinates of stars works as follows. At the beginning of the work, a portion of the starry sky in various spectral ranges is projected onto the photosensitive area of the matrix photodetector with a charge accumulation of 8 by sequentially switching the filters in the block of switched filters 3 using lens 4. Moreover, simultaneously with the switching of the filters, which is provided by the manager of the block of switched filters 2 by signals from the third output of the synchronizer unit 16, the exposure time in the array photodetector with accumulation of charge 8 also changes, which is provided by the unit for generating the variable exposure time 7 by commands from the generator of exposure switching commands 12 synchronized also by the third output of the synchronization unit 16.

Each of the obtained spectral images through the block of analog signal processing of the photodetector and analog-to-digital conversion 10 is sequentially fed to the block of digital processing and control 11, where they are amplitude-selected from calibration marks in the amplitude signal selector 13, separation of useful signals from interfering noise and interference in a block for extracting useful signals from interference 14, recognition of stellar objects in the form of a set of image elements corresponding to a single star in a block for recognizing stars 15. 15. As a result, for each spectral range, a set of images of stellar objects is obtained, obtained on the sensitive area of the matrix photodetector, which are recorded in the memory of the multispectral image forming unit of stars 17 for further processing. In the block for generating a multispectral image of stars 17 for each image of a stellar object, the average value of the magnitude of the image signal in each spectral range is estimated and the results of these calculations for each stellar object decide on the spectral range of its representation for measuring angular coordinates. The decision is made by simply selecting the maximum value from all the average values of the image signal over the spectral ranges for the current stellar object. It is these selected images of stars that make up the general multispectral representation of stellar objects, from which measurements of the angular coordinates of stars are formed. In the computing device for determining the angular coordinates of the stars 18, the linear coordinates of the multispectral images of stars are measured on a sensitive area of the matrix receiver and stored. The synchronization of the operation of the multispectral image forming unit of the stars 17 and the computing device for determining the angular coordinates of the stars 18 is carried out according to the fourth output of the synchronization unit 16. Then, according to the signal generated at the first output of the synchronization unit 16, the illuminator of the collimator unit with illuminator 6 is turned on and the image of the calibration marks is projected onto that the same photosensitive area. At the same time, according to the signal generated at the third output of the synchronization unit 16, through the exposure command generator 12 and the variable exposure time forming unit 7, the exposure of the matrix receiver decreases K times compared to what it was when working with stars. The illumination at the receiver in the image of the calibration marks and the K value are preselected so that the receiver signal from the calibration marks is greater than the signal from the brightest star. The image of the calibration marks is taken from the matrix photodetector with a charge accumulation of 8 and is fed through the analog processing and analog-to-digital conversion unit 10 to the amplitude signal selector 13. The images of the calibration marks highlighted by the amplitude signal selector 13 sequentially pass through the block for extracting the useful signal from interference 14, the recognition unit stars 15, the multispectral image forming unit of stars 17 and are directly fed to a computing device for determining angular coordinates INAT star 18, wherein counting is performed of the measured linear coordinates star in their angular position in the base coordinate system, taking into account the results of measurement of the linear coordinate marks and the calibration results of measurements performed in advance of the angular coordinates of these marks. The angular coordinates of the stars are output to the device for measuring the angular coordinates of the stars. Reads information about images from a matrix photodetector. The operation control unit of the matrix photodetector 9 is constantly synchronized by a signal from the second output of the synchronizer unit 16 from the digital processing and control unit 11.

We show that the set of essential features introduced into the method and device for measuring the angular coordinates of stars really leads to the achievement of the goal, namely, to increase the overall accuracy of measuring the angular coordinates of stars. The accuracy of the measurement is related to the observation conditions and the characteristics of the observation tool. The first are the relationship between the noise characteristics of the observation and the radiation intensity of stellar objects and the characteristics of the atmosphere (when observed from the Earth), the main of which is atmospheric turbulence. The latter are usually associated with the quality of the telescope optics and the characteristics of the conversion of light - electrical signal. All these factors together lead to the appearance of a background noise component of the observation signal and to the erosion of the point image of the star in the focal plane, and the magnitude and boundaries of this erosion are directly related to all these factors. As is known, the decisive factor in this case is the ratio of signal power to noise power [5]. The higher this ratio, the sharper the boundary that defines the stellar object on the noise background, and the less the variance of the error in estimating the coordinates of the object. Let the spectral sensitivity range of the array photodetector with charge accumulation be ΔF. Assuming that the spectral distribution of noise in this range is characterized by a uniform spectrum with a power spectral density of N _0/2 and the spectral sensitivity of the array photodetector with charge accumulation is also uniform. This means that the noise power in this spectral range is equal to ΔF N _0/2.

At the same time, the emission of stellar objects is uneven in its spectrum [6]. For example [7], the main navigation stars vary greatly in their spectral composition (Table 1).

The radiation power from a stellar object is determined by the integral:

P _s = ∫ _ΔF S (f) df,

where S (f) is the power emission spectrum of the star.

Table 1 Navigation star Stars value Color Sirius (α B. Dog) -1 ^m , 58 White Chapel (α Charioteer) 0 ^m , 21 Yellow Arcturus (α Bootes) 0 ^m , 24 Orange Procyon (α M. Dog) 0 ^m , 48 Yellow Altair (α Eagle) 0 ^m , 89 White Betelgeuse (α Orion) 0 ^m , 92 Red Aldebaran (α Taurus) 1 ^m , 06 Orange Spica (Virgo α) 1 ^m , 25 Bluish white

Since the accuracy of measuring coordinates is directly related to the signal-to-noise ratio, we define this ratio in each cell of the matrix photodetector with the accumulation of charge in the prototype device by the expression:

$${\left(\raisebox{1ex}{$\mathrm{FROM}$}\!\left/ \!\raisebox{-1ex}{$W$}\right.\right)}_{{}_{Pij}}=\frac{2k_{ij}{P}_s}{\Delta F{N}_0}=\frac{2k_{ij}{N}_s}{N_0}$$

Here k _ij is the coefficient taking into account the distribution of radiation energy over the surface of the matrix photodetector with charge accumulation due to atmospheric turbulence and other factors affecting the spatial coherence of the image, N _s is the average spectral power density of the star radiation.

In the proposed method and device, before projecting the image of the starry sky onto the surface of the matrix photodetector with the accumulation of charge, this image is filtered in a sequence of filters that completely cover the spectrum of the ΔF range. As a result of filtration, the total radiation spectrum is divided into a number of spectral regions. By changing the exposure time in the spectral ranges, the noise component in the output image signal is equalized inversely with the relative width of the spectrum of the corresponding range. This is equivalent to normalizing the magnitude of the signal in each range to its spectrum width ΔF _i , which allows you to select the range with the maximum specific intensity of the star signal and use it to determine the coordinates of stellar objects. For this purpose, the average radiation intensity of each stellar object is compared by its image in all spectral ranges. We prove that the signal-to-noise ratio for each stellar object during such processing is higher than in the prototype. To do this, consider what the signal-to-noise ratio in the cell of the matrix photodetector is with accumulation of charge in the present invention. In the proposed method and device, the spectral range ΔF is divided into M spectral regions, and at the first stage, the spectral region with the highest spectral radiation density is selected. We prove that in this case the signal-to-noise ratio in each cell of the matrix photodetector with charge accumulation will be the largest.

Then the power of noise in one of the M parts of (k-th) spectral range is equal to ΔF _k N _0/2. Accordingly, the radiation power from a stellar object in the k-th part of the spectral range is equal to:

. $$P_{sk}={\displaystyle \int {}_{\Delta F_k}}S\left(F\right)dt$$

.

Then the signal-to-noise ratio in each cell of the matrix photodetector with the accumulation of charge in the proposed device is defined as

$${\left(\raisebox{1ex}{$\mathrm{FROM}$}\!\left/ \!\raisebox{-1ex}{$W$}\right.\right)}_{{}_{ijk}}=\frac{2k_{ij}{P}_{sk}}{\Delta F_k{N}_0}=\frac{2k_{ij}{N}_{sk}}{N_0},$$

where N _zk is the average interval spectral density of the radiation power of the star.

If we assume that the emission spectrum of the star, as well as noise, is uniform in the band ΔF, the value of N _zk = N _z and, therefore,

$${\left(\raisebox{1ex}{$\mathrm{FROM}$}\!\left/ \!\raisebox{-1ex}{$W$}\right.\right)}_{{}_{ijk}}={\left(\raisebox{1ex}{$\mathrm{FROM}$}\!\left/ \!\raisebox{-1ex}{$W$}\right.\right)}_{{}_{Pij}}$$

However, in the case of an uneven distribution of intensity over the radiation spectrum, which is the case in practice and provided that the part with the maximum average interval spectral power density of star radiation is selected as the kth part of the spectral range, the signal-to-noise ratio in this part of the spectrum will be more i.e.

$${\left(\raisebox{1ex}{$\mathrm{FROM}$}\!\left/ \!\raisebox{-1ex}{$W$}\right.\right)}_{{}_{ijk\max }}>{\left(\raisebox{1ex}{$\mathrm{FROM}$}\!\left/ \!\raisebox{-1ex}{$W$}\right.\right)}_{{}_{Pij}}$$

This statement is obvious, since the distribution of noise in the range ΔF is uniform, and the total radiation power is limited to P _z

$$P_s={\displaystyle \sum _{k=\mathrm{one}}^M{\displaystyle \underset{\Delta F_k}{\int }S\left(f\right)df}=}{\displaystyle \sum _{k=\mathrm{one}}^M{P}_{sk}}$$

Thus, the accuracy of determining the coordinates of the star when using the spectral region with the maximum average interval spectral density of the radiation power of the star will be higher. Representation of the image of stellar objects in the form of a set of range images of different spectral ranges (multispectral image) allows you to select the most suitable spectral image of each stellar object for measuring coordinates. This in turn means that the set of distinctive features introduced is essential, i.e. the proposed method and device for measuring the angular coordinates of stars meet the requirements of the purpose of the invention, which is to improve the accuracy of measuring the angular coordinates of stars.

The multispectral images of stellar objects introduced into the method for measuring the angular coordinates of stars were not used in any of the known methods for measuring the angular coordinates of stars. Such a set of distinctive features is absent in the analogs and in the prototype, which proves the conformity of the proposed method to the criterion of "novelty."

In turn, the block of switched light filters inserted into the device for measuring the angular coordinates of stars included in the optical image path between the hood and the input element, the manager of the block of switched light filters and the block for generating a multispectral image of stars with corresponding connections are also absent in the analogs and in the prototype, which proves compliance with the criterion of "novelty" of the proposed device.

Thus, the analysis of the prior art did not reveal objects that have the same set of features as the claimed invention, and therefore, it is new.

The inventive step of the proposed method and device is confirmed by the fact that the search did not reveal methods and devices having features that match the distinguishing features of this invention. All traced directions for improving the systems for measuring the angular coordinates of stars, reflected in the scientific, technical and patent literature, do not use the spectral features of star radiation and do not use the results of combining several spectral ranges to determine the angular coordinates of stars in the interests of navigation problems. This means that the claimed invention does not follow explicitly from the prior art, and therefore has an inventive step.

Information confirming the possibility of carrying out the invention

Industrial applicability of the invention is determined by the possibility of implementing its nodes and blocks at the current level of technology. The possibility of technical implementation of the elements of the device, matching the purpose of the prototype, is not in doubt. To implement a block of switched light filters, a rotating cassette block with electromechanical control can be used, which uses industrial filters of the main spectral ranges of star radiation: from red to blue. The commander of the switchable filter block is a conventional driver of control voltages for a mechanical actuator. The multispectral imaging unit for stars is a digital device with a standard set of elements for digital signal processing, such as RAM, ROM, ALU, input / output ports with appropriate software and system software. It can be implemented according to the standard scheme of a specialized digital microprocessor unit using modern high-speed microprocessor sets of well-known developers of digital signal processing systems such as Analog Devices or Texas Instruments.

Thus, the claimed invention is industrially applicable. It can be used in astroorientation and astronavigation systems to accurately determine the angular positions of navigational luminaries and has advantages over the well-known ones associated with increasing the accuracy of measuring the angular positions of stars, which determines its technical and economic efficiency.

Literature

1. Kuzmin V.S., Fedoseev V.I., Zaeekin V.I. New generation of star sensors. Proc. SPIE, 2739-41, Acquisition, Tracking and Pointing X, 1996, vol. 2739

2. Petrovich V.A. Small star sensor. Optical Journal, 1996, No. 7, pp. 48-49.

3. Fedoseev V.I., Kolosov M.P. Optoelectronic devices for orientation and navigation of spacecraft. Moscow, Logos, 2007, p. 156-160.

4. Patent RU 2408849 C1, G01C 21/24, G01B 11/26, claimed. 05/20/2009

5. D. Barton, G. Ward. Handbook of radar measurements. M .: Soviet Radio, 1976.

6. James B. Kaler. Stars and their spectra: an introduction to the spectral sequence. - Cambridge University Press, 1997 .-- P.62-63. - 300 p.- ISBN 0-521-58570-8, ISBN 978-0-521-58570-5.

7.http: //astro.uni-altai.ru/files/12ns.html.

Claims (5)

1. A method of measuring the angular coordinates of a star-measuring star device based on an array photodetector with charge accumulation, including projecting onto a photosensitive surface of a matrix photodetector with charge accumulation through an image lens of a portion of the starry sky, measuring the linear coordinates of the centers of the image of stars on a photosensitive area of the receiver, projecting onto a photosensitive surface of the matrix photodetector with the accumulation of charge through a lens of special caliber markers formed by the geometric standard channel collimator and rigidly connected with the base instrument coordinate system implemented by the instrument structural elements; moreover, when projecting calibration marks, the signal accumulation time in the receiver is set to K times less than when working with stars, and the magnitude of the reduction in the accumulation time K and the illumination of the images of the calibration marks are pre-selected so that the signal at the receiver output from the brightest working star is less than the signal t calibration points, the amplitude selection of the signals of the calibration marks according to the criterion for exceeding a pre-selected threshold level exceeding the signal from the brightest star, and measuring the linear coordinates of the centers of the images of the calibration marks on the photosensitive surface of the matrix photodetector with the accumulation of charge, recalculating the linear coordinates of the centers of the images of stars in angular coordinates stars in the base instrument coordinate system taking into account the results of measurements of the linear coordinates of the centers of the image of potassium reference points at their known angular coordinates, characterized in that the image of the starry sky portion is formed on the photosensitive area of the array photodetector with the accumulation of charge in three or more (M) spectral ranges by pre-filtering the light flux from the selected portion of the starry sky in the filter system, moreover exposure time in each spectral range is inversely proportional to the relative width of this spectral range, from the obtained range images images of objects are extracted from the starry sky for all spectral ranges and multispectral images of stellar objects are formed from them by selecting for each stellar object images of that spectral range, the average amplitude in which is the largest among all range images of a given star, the linear coordinates of the centers of image of stars are selected coordinates of the centers of multispectral images of stars. 2. A device for measuring the angular coordinates of stars, including a lens hood, a channel of a geometric standard (CGE), made in the form of a collimator unit with a illuminator, forming images of calibration marks, and an input element that implements the image of calibration marks in the lens, lens, and photodetector with accumulation of charge , the photosensitive area of which is located in the focal plane of the lens, the array photodetector control unit with charge accumulation, the outputs of which are connected to the control to them the inputs of the matrix photodetector with charge accumulation, the unit for generating a variable exposure time, the output of which is connected to the input of the exposure of the matrix photodetector with charge storage, the unit for analog processing and analog-to-digital conversion, the input of which is connected to the output of the matrix photodetector with charge storage, the digital processing unit and control, the input of which is connected to the output of the block of analog processing and analog-to-digital conversion, the first output is connected to the input of the collimator unit with lighting by the body, the second output is connected to the input of the matrix photodetector operation control unit with charge accumulation, the third output is connected to the input of the variable exposure time generation unit, and the fourth output is the output of the star angular coordinate measuring device, the digital processing and control unit includes a series-connected amplitude signal selector, the input of which is the input of the digital processing and control unit, the unit for extracting useful signals from interference and the star recognition unit, and switching the exposure of the matrix photodetector, the output of which is the third output of the digital processing and control unit, a computing device for determining the angular coordinates of the stars, the output of which is the fourth output of the digital processing and control unit, and a synchronization unit, the first and second outputs of which are the first and second outputs, respectively of the digital processing and control unit, its third output is connected to the input of the shaper of commands for switching the exposure of the matrix photodetector, and the fourth the output is connected to the synchronization input of the computing device for determining the angular coordinates of the stars, characterized in that the device further includes a switchable filter block included between the hood and the input element and forming a switchable filter block in the hood sequence, the input element, the lens is an optical image path , the manager of the switchable filter unit, the output of which is connected to the control input of the switchable filter unit, and into the digital processing unit The fifth output, which is the third output of the synchronization unit and connected to the input of the manager of the switchable filter block, the multispectral image forming unit of the stars, the input of which is connected to the output of the star recognition unit, the output is connected to the input of the computing device for determining the angular coordinates of the stars, and the input synchronization is connected to the fourth output of the synchronization unit. 3. The device for measuring the angular coordinates of stars according to claim 2, characterized in that the switchable filter unit is made in the form of a cassette unit with mechanical control. 4. The device for measuring the angular coordinates of stars according to claim 2, characterized in that the multispectral image forming unit of the stars and the computing device for determining the angular coordinates of the stars include a storage device. 5. The device for measuring the angular coordinates of stars according to claim 4, characterized in that the storage device is made in the form of non-volatile memory or in the form of any other type of memory.