Determination of emergency object coordinates by elevation angle and time doppler method
FIELD: space engineering; spacecraft flying in earth artificial satellite orbit, but for geostationary orbit stabilized by rotation along vertical axis.
SUBSTANCE: system used for realization of this method includes spacecraft case, infra-red horizon pulse sensor, receiving antenna, comparison unit, receiver, Doppler frequency meter, biased blocking oscillator, two AND gates, two rectifiers, pulse generator, pulse counter, switching circuit, magnetic storage, transmitter, transmitting antenna, onboard timing device, onboard master oscillator and emergency object transmitter. Doppler frequency meter includes 90-deg phase shifter, two mixers, two difference frequency amplifiers, 180-deg phase inverter, two AND gates and reversible counter. Frequency of received oscillations is preliminarily reduced in two processing channels.
EFFECT: enhanced accuracy of determination of coordinates due to accurate measurement of minor magnitudes of Doppler frequency and recording its zero magnitude.
The proposed method belongs to the space technology and can be used on the spacecraft that are in orbit of an artificial Earth satellite, in addition to geostationary stabilized by rotation along the vertical axis.
Known methods and systems of determining the coordinates of the emergency object (RF patents №№2.155.352, 2.158.003, 2.040.860, 2.59.423, 2.174.092, 2.193.990, 2.201.601, 2.206.902, 2.226.479, 2.240.950; U.S. patent No. 4.161.730, 4.646.090, 4.947.177; Scuba R.A. and other Companion at the helm. - Leningrad: Sudostroenie, 1989. - 168 C. and others).
Known methods and systems closest to the proposed is "Elevation time-Doppler method for determining coordinates of the emergency object (patent RF №2.174.092, 64G 1/10, 1999), which is selected as a prototype.
According to a known method searches for such a spatial position of the receiving antenna of the satellite in the event of operation of the transmitter of the emergency object, when the Doppler frequency of the received signal is equal to zero. At this point, measure the angle between the axis of the receiving antenna and the axis of the horizon sensor. The coordinates of the ground point of the track of the spacecraft at the time of measurement are calculated. The measurement is carried out twice. The coordinates of the two ground points and two dimensions of the specified angle determine the location of the emergency object.
There is a method provided the AET unambiguous definition and improving the accuracy of calculating the coordinates of the emergency object located on the Earth's surface, as well as the expansion of the area of the viewing surface and increase the signal-to-noise ratio in the receiving radio.
For the implementation of this method at the emergency object is a transmitter of signals having a high frequency stability. On Board the spacecraft (SC) is a measuring device, having in its composition a highly stable frequency standard, a frequency of which is equal to the frequency of the emergency transmitter or differs from it by a fixed amount. The comparison of the frequency of the received oscillations with a frequency reference allows you to set the value of the Doppler frequency offset and determine the speed.
However, it is necessary to provide very high frequency stability of the transmitter and the reference generator.
Really, only to notice the Doppler change in frequency that occurs when the motion of the SPACECRAFT with velocity V, it is necessary to provide a relative frequency instability of the radiated oscillations of not less than
where c is the speed of propagation of radio waves.
Provided that V=8 km/s, have
If you want not only to replace the Doppler shift frequency, but also to measure the velocity modulus with error ΔV, then carried ailnoth frequency should be significantly reduced, and it is at least V/Δ (V) times. General instability frequency of the radiated oscillations δ must be
Thus, for measuring small values of the Doppler frequency Fdand fixing its zero value when passing KA points abaft the beam frequency stability of the transmitter of the emergency object must be very high. This circumstance is a disadvantage of the known method and an obstacle to the wide use of no-request method of measuring the Doppler frequency.
An object of the invention is to improve the accuracy of measuring small values of the Doppler frequency and record its zero value by pre-reduction of the frequency of the received oscillations using heterogenerous two channels of processing.
The problem is solved by the fact that according to elevation and temporal Doppler method for determining coordinates of the emergency object placed on the surface of the Earth via spacecraft, stable rotation along the vertical axis, namely, that when the signal transmitter of the emergency object is displayed with a spacecraft strip on the surface of the Earth measured Doppler frequency no-request method, find the spatial location of kosmicheskogo apparatus at the moment when the Doppler frequency of the received signal is equal to zero, measure at this point in time, the angle between the mechanical axis of the receiving antenna of the spacecraft and the axis of the horizon sensor with reference measurements to the on-Board time, compute the coordinates of the sub-satellite point at the time specified dimension, and the measurement is carried out twice and the coordinates of the two ground points and two measurements of the angle between the mechanical axis of the receiving antenna of the spacecraft and the axis of the horizon sensor to determine the location of the emergency object on the Earth's surface, for measuring Doppler frequency no-request method uses two channels of processing, in which receive the signal, convert the frequency using a master oscillator, in the first processing channel voltage oscillator shift the phase by 90°allocate the voltage difference frequency, amplify and limit their amplitude, converting into clipped voltage of rectangular form, clipped voltage of the first channel processing is converted into a sequence of short positive pulses, the temporal position of which correspond to the points of transition of the voltage through zero with a positive derivative, and clipped the voltage of the second channel processing invert the phase by 180 received a short positive pulses quantuum neighboring positive voltage clipped voltage of the second channel processing, compares them with each other and automatically digitally determine not only the magnitude of the Doppler frequency, but also its sign, a value of zero Doppler frequency, which corresponds to the passage of the spacecraft points abaft the beam, forming a control pulse to permit further processing of the received signal.
The geometric layout of the SPACECRAFT and two ground points shown in figures 1 and 2. Structural diagram of on-Board equipment SPACECRAFT is shown in figure 3.
Onboard equipment SPACECRAFT includes a housing 1, a pulsed infrared sensor 2 horizon and consistently included receiving antenna 3, is hosted on the same axis opposite to the infrared sensor 2 horizon mechanical axis which does not coincide with the axis of rotation of the SPACECRAFT, the receiving device 5, a second input connected to the output of the onboard oscillator 19, 6 meter Doppler frequency, the device 4 comparison inhibited the blocking generator 7, a diagram And 9, a second inlet through which the schema And 8 is connected to the second outputs of the receiving device 5 and the blocking-oscillator 7, the valve 10, the circuit 14 of the switching magnetic storage device 15, a transmitter 16, a second input which is outinen with the second output of the circuit 14 of the switching and transmitting antenna 17. The second output of the onboard oscillator 19 are connected in series side temporary device 18 and the valve 11, the second input is connected with the second output of the circuit And 9, and the output connected to the second input circuit 14 of the switching. The output pulse of the infrared sensor 2 horizon connected counter 13 pulses, a second input connected to the output of the pulse generator 12, and the output is connected to the second input of gate 10.
The 6 meter Doppler frequency contains two channels of processing, each of which consists of sequentially connected to the first output of the receiving device 5, the mixer 22 (23), a second input connected to the first output of the onboard oscillator 19 through the phase shifter 21 90° (and directly), amplifier 24 (25) of the difference frequency and the amplifier-limiter 26 (27). The output of the amplifier-limiter 26 connected in series shaper 28 pulses, the first circuit 30, a second input connected to the output of the amplifier-limiter 27, and a summing input of reversible counter 32, the output of which is connected to the input of the 4 comparisons. The output of the amplifier-limiter 27 serially connected inverter 29 180° and the second circuit And 31, the second input of which is connected to the output of the shaper 28 pulses, and the output is connected to wikitude is at the input of the reversible counter 32.
The proposed method is as follows.
The translational motion of the SPACECRAFT in its orbit is carried out with a linear velocity V. Small segment of the orbit close to the point And the beam will assume a straight line. The axis of rotation KA rejected from the local vertical, it does not coincide with the mechanical axis of the receiving antenna 3. Pulse transmitter 2 horizon placed on the same axis opposite to the reception antenna 3 (1, 2).
The translational motion of the SPACECRAFT, the axis of rotation of which is rejected from the local vertical, moves the scan line pattern of the receiving antenna 3 and consistent view of the strip on the surface of the Earth along the orbit of the spacecraft. The rotation frequency of the AC is selected from the viewing conditions of the Earth's surface without a badge. Receiving antenna 3 is chosen such that the axis of the beam coincides with the mechanical axis of the antenna. To disambiguate the mechanical axis of the receiving antenna 3 spacecraft is shifted relative to the axis of rotation at an angle βequal to the width of the directional receiving antenna (1, 2).
When the signal
where Ucthat ωcthat ϕc, Tc- amplitude, carrier frequency, initial phase, and long is inost signal
the transmitter 20 of the emergency object in the viewed band on the surface of the Earth, it is from the output of the receiver 5 is supplied to the first input of the mixers 22 and 23 meter 6 Doppler frequency, to the second input of which is supplied the voltage of the onboard oscillator 19 through the phase shifter 21 90° and directly, respectively:
where UGthat ωGthat ϕGthe amplitude, frequency and initial phase of the voltage reference generator 19.
At the output of the mixers 22 and 23 are formed voltage Raman frequencies. Amplifiers 24 and 25 are voltage difference frequency, i.e. the frequency detuning (frequency beating):
K1- gain mixers;
ωp=ωc-ωG- intermediate frequency;
coming to the inputs of limiting amplifiers 26 and 27, respectively. If the frequency ωwiththe received signal is above the frequency ωGmaster oscillator 19, the voltage difference frequency up1(t) and up2(t), videla is by amplifiers 24 and 25 of the difference frequency, will be shifted relative to each other by 90°, otherwise -90°. Therefore, a phase shift of the difference frequency ωpjumps up to 180° with the change of sign of the detuning.
Measurement of the difference frequency ωpis electron-counting method. For this voltage difference frequency up1(t) and up2(t) is converted with the help of limiting amplifiers 26 and 27 in the clipped voltage of rectangular shape. Moreover, the voltage of the rectangular shape from the output of the amplifier-limiter 26 using the shaper 28 pulses is converted into a sequence of short positive pulses, the temporal position of which correspond to the points of transition of the voltage through zero with a positive derivative. The voltage of the rectangular shape from the output of the amplifier-limiter 27 is inverted in phase by 180° with the help of the inverter 29. The short positive pulses are received on the input schema matching And 30 and 31, the second input of which is supplied a voltage of rectangular shape with the output of the amplifier-limiter 27. Short positive pulses appear at the output of the pattern matching And 30 and 31, the output of which the moments of occurrence of short positive pulses coincide with the positive rectangular voltage is Oia, and their number will be determined by the frequency detuning ωp. Indications reversible counter 32 will correspond to the size and sign of the detuning (Doppler frequency).
Thus, the 6 meter Doppler frequency allows to automatically determine not only the magnitude of the Doppler frequency, but also its sign.
The advantage of this meter is a high accuracy of measurement and presentation of measurement results in binary code.
When reaching the Doppler frequency value of zero, the mechanical axis of the receiving antenna 3 is located at the point of beam. At this point, the device 4 comparison of the generated impulse control to permit further processing of the received signal. At the same time measured the angle between the axis of the sensor 2 of the horizon and the position of the mechanical axis of the receiving antenna 3 (angle α). Measurements are linked to the onboard time device 18 and stored in the magnetic storage device 15 or transmitted via the transmitter 16 on the surface receiving the item. To determine the coordinates of the emergency object you want to measure the angle α and calculating the coordinates of ground point. The coordinates of the two ground points and two measured angles α1and α2is uniquely determined by the location of the emergency object is A.
Calculating the coordinates of the emergency object may on Board the SPACECRAFT in the presence of on-Board digital computing machine or on the surface receiving the item.
In the initial state before getting signal from the transmitter 20 of the emergency object in the directivity pattern of the receiving antenna 3 at the output of receiver 5 no signal. The output schema matching And 8 is zero. Schema matching And 9 is closed, the outputs of schema matching And 9 - zero. Pulse or infrared sensor 2 horizon at the moment of crossing the track of the spacecraft produces a pulse which resets the counter to zero 13 pulses. From generator 12 pulses pulses are received by the counter 13. Schema matching And 9 is closed, the valves 10, 11 are closed.
When the signal from the transmitter 20 of the emergency object in the band of the earth's surface that is viewed by the directivity of the receiving antenna 3, a signal at the output of the receiver 5. The output schema matching And 8 - unit. Upon reaching the values of the Doppler frequency at the output of the meter 6, is equal to zero, opens the device 4 comparison that generates a control pulse. Recent launches inhibited the blocking generator 7, the outputs of schema matching And 9, you receive the unit. Open the valves 10, 11. Information about the angle α (the number of pulses stored in the counter 13 pulses) and time and the measurement is recorded through the circuit 14 switching on a magnetic storage device 15. In the reception area ground control station spacecraft information is reset to the magnetic storage device 15 through the transmitter 16 and the transmitting antenna 17.
When the trigger pulse of the sensor 2 of the horizon system is returned to its original state.
The sequence of the above operations allow us to determine the coordinates of the emergency site, to reduce the time of search, to increase the area of the viewing surface of the Earth due to the scanning of the receiving beam, to increase the ratio signal/noise radio reception through the use of receiving antennas with a narrow radiation pattern.
Thus, the proposed method is compared with the prototype and other technical solutions for a similar purpose to improve the accuracy of measuring small values of the Doppler frequency and the fixation of its zero value. This is achieved by pre-reduction of the frequency of the received oscillations using heterogenerous two channels of processing. The advantage of the proposed method is also the representation of the result of measurement in binary code.
In the system that implements the proposed method does not exhibit any specific stringent requirements for stability of the carrier frequency ωwithemitted by a transmitter and a receiver is om of the emergency object. This is a significant advantage.
Elevation time-Doppler method for determining coordinates of the emergency object placed on the surface of the Earth, with the spacecraft stabilized by rotation along the vertical axis, namely, that when the signal transmitter of the emergency object is displayed with a spacecraft strip on the surface of the Earth measured Doppler frequency no-request method, find the spatial location of the spacecraft at the time when the Doppler frequency of the received signal is equal to zero, measure at this point in time, the angle between the mechanical axis of the receiving antenna of the spacecraft and the axis of the horizon sensor with reference measurements to the on-Board time, compute the coordinates of the sub-satellite point at the time specified dimension when this measurement is carried out twice and the coordinates of the two ground points and two measurements of the angle between the mechanical axis of the receiving antenna of the spacecraft and the axis of the horizon sensor to determine the location of the emergency object on the Earth's surface, characterized in that for measuring the Doppler frequency no-request method uses two channels of processing in which the received signal transform for the frequency using the on-Board oscillator, whereas the om in the first processing channel voltage oscillator shift the phase by 90° allocate the voltage difference frequency, amplify and limit their amplitude transform in the clipped voltage of rectangular form, clipped voltage of the first channel processing is converted into a sequence of short positive pulses, the temporal position of which correspond to the points of transition of the voltage through zero with a positive derivative, and clipped the voltage of the second channel processing invert the phase by 180°received short positive pulses quantuum neighboring positive voltage clipped voltage of the second channel processing, compares them with each other and automatically digitally determine not only the magnitude of the Doppler frequency, but also its sign, a value of zero the Doppler frequency, which corresponds to the passage of the spacecraft points abaft the beam, forming a control pulse to permit further processing of the received signal.
FIELD: satellite systems.
SUBSTANCE: proposed system that can be used as orbital system forming global radio-navigation field for marine, ground, low-, and high-altitude orbital space users at a time as well as for exchanging command information with allocated circle of users, including space vehicles flying on near-earth orbits has navigation system satellites provided with intersatellite communication equipment, navigation information transfer equipment, and equipment transferring telemetering information to ground command-measuring systems incorporating transceiving equipment transferring navigation, telemetering, and command information to satellites; ground users have navigation information receivers; newly introduced in each ground command-measuring system are code command inputting equipment and acknowledgement signal receiving equipment connected to transceiving equipment; introduced in satellites are acknowledgement signal receivers connected to transceiving equipment; code command allocating devices connected to navigation information receivers and acknowledgement signal transmitters are installed on some users. Radio field produced by positioning system and its relaying capabilities are used not only for locating users in navigation but also to exchange command-program information between ground control center and allocated user.
EFFECT: enlarged functional capabilities.
FIELD: the invention refers to radio technique and may be used in global mobile systems of communication applying cellular technology.
SUBSTANCE: the technical result is increasing reliability without essential complication of the construction of the system. For this the system has a block of transceivers, a commutation matrix, a block of antennas, a block of detecting an accidental transceiver, a control block and a block of variants of commutation. At that in such a system there is possibility of replacement of the accidental transceiver of one of the central cellular cell with a transceiver of one of the edge cellular cells without essential complication of the construction.
EFFECT: increases reliability of the system.
FIELD: communications engineering, possible use in cell phone communications.
SUBSTANCE: in accordance to invention, by means of GPS relay of vehicle, activated in response to signal, incoming from control center via individual radio information channel, data about position received from satellites are received and transferred, and information about position is transferred by means of control channel to control center, and then the data and information are transferred to user of mobile cell phone. System may also be used by dispatchers in car parks.
EFFECT: possible usage of one portable cell phone only for voice communications by means of voice radio channel with cell phone network control center for requesting information or data about position and other services.
2 cl, 1 dwg
FIELD: wide-range high-altitude communication systems incorporating satellite groups launched into different-altitude orbits and at least one ground-based control station.
SUBSTANCE: proposed system that has satellite group launched into geostationary orbit, satellite group injected into low-altitude orbit, and at least one ground-based control station is provided in addition with satellite group launched into medium-altitude orbit, at least one satellite disposed on geostationary orbit being connected through communication line with ground-based control station; satellites injected into geostationary orbit are interconnected via high-speed communication lines and are designed for relaying control signals from ground-based control station to satellites disposed on medium- and low-altitude orbits whereto they can be connected by means of communication line, and also for relaying information signals received from satellites disposed on medium- and high-altitude orbits to ground-based control station; each of satellites disposed on low-altitude orbit can communicate with at least one of satellites disposed on medium-altitude orbit and each of satellites disposed on this orbit, with one of satellites disposed on geostationary orbit.
EFFECT: provision for communications and monitoring at minimal quantity of space vehicles.
1 cl, 1 dwg
FIELD: methods for determining locations of objects by ground-based and space-based radio-navigation devices, possible use in rotation-stabilized spacecrafts.
SUBSTANCE: suggested method includes measuring Doppler frequency by query-less method on detection of emergency object transmitter signal within detection range of receiving antenna of spacecraft. Spatial location of spacecraft is measured in moments when Doppler frequency of received signal equals zero. Measured twice in these moments is the angle between antenna axis and horizon sensor axis with alignment of measurement to onboard time of spacecraft, and coordinates of sub-satellite points are calculated. Position of emergency object on Earth surface is determined using coordinates of given points and values of aforementioned angle. Additionally, when spacecraft appears in receipt zone at ground control station a high frequency oscillation is generated on original frequency, which is transformed by means of first heterodyne to signal (voltage) on first intermediate frequency. This signal is amplified, emitted into ether and received on spacecraft, where it is transformed by means of second heterodyne to signal on second intermediate frequency. Given signal is phase-manipulated by modulating code with information about position of emergency object, emitted into ether and received at ground control station. There it is transformed by means of third heterodyne to voltage with third intermediate frequency, from which after phase transformations the harmonic oscillation at original frequency is selected. The oscillation is used as supporting voltage for synchronous detection of aforementioned signal at third intermediate frequency. Low frequency voltage, proportional to modulating code, is selected, harmonic oscillations at original frequency are compared, Doppler frequency is measured by query method and spacecraft orbit elements are determined. For realization of aforementioned method, appropriate equipment is suggested, mounted onboard the spacecraft or at ground control station.
EFFECT: expanded functional capabilities of suggested method due to control over transfer of information from spacecraft to ground-based station and to more precise determining of spacecraft orbit elements.
FIELD: radio engineering.
SUBSTANCE: newly introduced in proposed satellite communication system relay station that can be used in communication and control systems as well as in combined command-trajectory radio links wherein parameters of movement are measured in addition to transmission of command information are three command signal decoders; novelty is also that signal extraction unit provides for separating compact signals and its control command output is connected to inputs of three command signal decoders.
EFFECT: enhanced throughput capacity and precision of synchronization in communication and control system.
1 cl, 1 dwg
FIELD: data message transfer over television channels through space relay station.
SUBSTANCE: additionally introduced in space information system that has ground-based transmitting center is receiver which transforms in into transceiving center. Additionally introduced in local information-shaping center are demodulator, decoder, and terminal (display). Newly introduced in relay station are demodulator, decoder, web-service, coder, modulator, return-channel frequency converter, return-channel intermediate-frequency amplifier, return-channel demodulator, return-channel decoder, return-channel coder, return-channel modulator, second return-channel frequency converter, and return-channel power amplifier.
EFFECT: enhanced efficiency of system control and control of transmitted and received information.
1 cl, 3 dwg
FIELD: technology for determining position of mobile stations in cell communication networks, in particular, auxiliary messages of global positioning system for mobile stations, transferred to cell phones, and methods for realization of same.
SUBSTANCE: identifiers of GPS ephemerid data output indicate whether renewal of GPS data is needed, for example, of appropriate ephemerid data and anthology data, stored in mobile station (104). In architecture of wideband multi-access with code division of channels of universal mobile telecommunication system (W-CDMA/UMTS) of 3-d generation, auxiliary GPS message is represented by a block of system information (SIB), and GPS ephemerid data identifier and appropriate satellite identifier are encoded in value sign, included in setting information block.
EFFECT: decreased power consumption of mobile stations, resulting in increased resource of same.
3 cl, 4 tbl
FIELD: controlling potentially hazardous entities as well as protecting them and population against man-caused natural and terroristic threats.
SUBSTANCE: information-logic basis of computerized on-line monitoring systems has been developed including unified technology of building primary data acquisition systems from miscellaneous entity monitoring systems; unified technology of building hierarchy systems for computerized on-line entity checkup for condition and for data exchange in the framework of their structure; unified technology of data exchange between computerized on-line monitoring systems for potentially hazardous objects and public authority information support systems.
EFFECT: enhanced operating efficiency of monitoring system.
8 cl, 16 dwg
FIELD: radio communications, possible use in global space systems for relay and communications.
SUBSTANCE: method for communication with low orbit spacecrafts in satellite communication system features forming of narrow directional diagram during communication session on high orbit relay satellite in direction towards low orbit spacecraft, while maximal α and minimal β angles of deviation of directional diagram of antenna of high orbit relay satellite from axis, passing through center of Earth and point of location of high orbit relay satellite are selected from conditions α = arc sin RLSC/RRS and β = arc sin R3/RRS, where RLSC - radius of orbit of low orbit spacecraft, RRS - radius of orbit of high orbit relay satellite, R3 - radius of earth and within limits of given angle, directional diagram of antenna of low orbit spacecraft is formed.
EFFECT: simplified construction of antenna system of low orbit spacecraft and increased resistance of communication lines to interference.
FIELD: power supply systems for high-orbit and geostationary orbit communication satellites whose orbits are corrected by means of electric jet engines.
SUBSTANCE: proposed method consists in determination of power requirements for each items of onboard using equipment for all spacecraft of cluster, electric jet engines inclusive. In case some items of onboard using equipment are not provided with electric energy at interval of dynamic mode with the aid of electric jet engines, this mode is changed-over for another permissible interval. In case of absence of permissible intervals, duplicate spacecraft of equivalent payload are selected. Items of equivalent using equipment of main spacecraft which are not provided with electric power are changed-over to duplicate spacecraft which are provided with required electric power. Spacecraft equipment items are changed-over till restoration of power supply on board main spacecraft (upon completion of dynamic modes of these spacecraft). Then control of power supply is performed for spacecraft of orbital cluster of later performance of dynamic modes. Main spacecraft are used as duplicate spacecraft.
EFFECT: reduced power requirements of cluster spacecraft; possibility of supplying power for additional items of using equipment.
1 dwg, 1 tbl
FIELD: space engineering.
SUBSTANCE: proposed method is based on continuous measurement of parameters of orbital space station motion. In addition to parameters of space station motion, its motion relative to center of mass is measured. Object of known shape and mass is separated from station in section of orbit when engines are disconnected and orientation of station is maintained with the aid of gyrodynes. Simultaneously parameters of motion of object separated from station in orbit and parameters of its rotary motion are measured. Mid-section of separated object is determined by measured parameters of rotary motion. Density of atmosphere is determined by this mid-section and measured parameters of motion of separated object. Then, mid-section area of orbital station is determined by measured parameters of its rotary motion and attitude of its movable parts. Then, mass of orbital station is determined from the respective mathematical expression by the mid-section area and atmosphere density and by measured parameters of motion. Proposed method does not require supply of calibrating and measuring pulses by power plant of cargo spacecraft coupled with station as distinguished from known methods.
EFFECT: saving of working medium; enhanced operational safety of cargo spacecraft.
FIELD: information satellite systems; forming global radio-navigational field for sea-going ships, ground, air and space vehicles.
SUBSTANCE: proposed system includes many low-orbit spacecraft whose number depends on conditions of global covering of access areas of users. Each spacecraft contains communication unit in addition to navigational equipment for communication of this spacecraft with two other spacecraft in its orbital plane and two spacecraft from adjacent orbital planes. Communication is performed in millimetric wave band absorbed by Earth atmosphere. At least one spacecraft is provided with high-accuracy synch generator. Thus spacecraft group is formed which is provided with noise immunity system of relaying and measuring radio lines connecting all spacecraft groups and navigational radio line covering upper hemisphere.
EFFECT: enhanced reliability and accuracy; enhanced noise immunity of data fed to users of satellite system.
FIELD: highly accurate ground and space systems.
SUBSTANCE: invention relates to frame-type stable-size bearing structures made of laminated polymeric composite material. Proposed integral framed construction made of laminated polymeric composite material consists of right angle ribs and their connecting units forming, together with ribs, a monolithic load-bearing skeleton made of layers of fibrous material impregnated with polymeric binder lying in plane of frame. Each rib and each unit has at least one layer of fibrous material fibers in which are orientated along longitudinal axis of rib, and layers of fibrous material fibers in which are orientated in directions corresponding to direction of longitudinal axes of other ribs.
EFFECT: increased stability and accuracy of positioning of frame units, reduced variations of thermomechical properties along length of ribs, provision of high accuracy of dimensions of articles.
2 cl, 2 dwg
FIELD: satellites of small mass and methods of mounting them on carriers.
SUBSTANCE: proposed mini-satellite has body in form of parallelepiped, solar battery panels secured on its side plates and units for connection with separation system which are located on one of side plates and on end plate. Each panel is made in form of tip and root parts articulated together. Root parts of panel are articulated on side plate of mini-satellite body where connection units are mounted. Mechanical locks mounted on opposite side plate are used for interconnecting the tip parts of panels and for connecting them with body. Articulation units are provided with drives for turning of parts. Articulation units are located above mechanical locks relative to plate on which these locks are mounted. Novelty of invention consists in reduction of area of end part of mini-satellite by 35%, reduction of its height in center of cross section by 23%, reduction of mass by 6-7% and increase of density of arrangement by 17-18%.
EFFECT: enhanced efficiency; increased number of mini-satellites carried on adapter.
FIELD: spacecraft inter-planetary flights with the aid of cruise jet engines, mainly electrical rocket engines.
SUBSTANCE: proposed method includes injection of spacecraft into heliocentric trajectory at distance of spacecraft from Sun followed by its approach to Sun. Active motion of spacecraft is realized in part of this trajectory behind Earth's orbit during operation of jet engines. Then, spacecraft returns to Earth at velocity increment and increases its heliocentric velocity in the course of gravitational maneuver near Earth. After spacecraft has crossed Earth's orbit in section of its approach to Sun and before entry into Earth's gravisphere, spacecraft is accelerated by repeated switching-on of cruise jet engines. At the moment of fly-by over Earth when gravitational maneuver is performed, angular motion of Earth and spacecraft relative to Sun are equalized. During fly-by over Earth, spacecraft is subjected to its gravitational field changing the vector of spacecraft heliocentric velocity, thus ensuring further acceleration of spacecraft and forming inter-planetary trajectory of flight to target.
EFFECT: reduction of time required for organization of gravitational maneuver in Earth's gravity field at injection of spacecraft into required inter-planetary trajectory.
FIELD: control of group of satellites in one and the same orbit or in crossing longitude and latitude ranges of geostationary orbit.
SUBSTANCE: proposed method consists in measurement of parameters of satellite orbits, determination of orbital elements, comparison of them with required ones and performing of correcting maneuvers with the aid of thrusters. Satellite inclination vectors are brought to circular areas of their permissible change which are spaced apart so that angle between line connecting the end of vector with center of its circular area and direction to Sun should exceed right ascension of Sun by 180°. According to first version, vectors of satellite eccentricity are shifted to similar circular areas so that similar line lags behind direction to the Sun by half angular displacement of vector over circumference of its natural drift within circular area. Then, distances between satellites are changed within required limits compensating for quasi-secular increment of inclination vector and correcting eccentricity vector so that at passing the center of interval between point of circumference entry of its natural drift to its circular area and point of exit from this area, line connecting the center of this circumference and center of circular area coincide with direction to the Sun. In case circular area of permissible change of each eccentricity vector is close to circumference of its natural drift (second version), said line for this area is matched with direction to the Sun and no correction is made in this case.
EFFECT: saving of propellant for correction; protracted flight of satellites at safe distance.
3 cl, 13 dwg
FIELD: global satellite information systems.
SUBSTANCE: proposed system and method of organization of communication with the aid of this system includes injection of satellites into inclined elliptical orbits ensuring simplified tracking of satellites by means of ground tracking stations. Satellite orbits form pair of repeated routes (130, 140) embracing the earth's globe in projection on ground surface. Satellites are activated on each of these routes only on active arcs located considerably higher or lower relative to equator, thus emulating some essential characteristics of geostationary satellites. Parameters of satellite orbits are so set that final points of active arcs of two routes coincide; point at which active arc terminates in one route coincides with point where active arc starts on other route. Satellites placed on such active arcs are accepted by ground station located in satellite servicing zone as satellites slowly moving in one direction at rather large elevation angle. Their trajectory in celestial sphere has shape of closed teardrop line.
EFFECT: increased capacity of global satellite communication system with no interference in operation of geostationary satellites; simplifies procedure of tracking satellites.
39 cl, 15 dwg, 1 tbl
FIELD: illumination of separate sections of planet surface at night.
SUBSTANCE: proposed method consists in illuminating the night surface of planet by sunlight. One section is formed as circle and other sections are formed as circular rings of large diameter. All sections are lighted-up by rays scanning at rate no less than several revolutions per second setting-up these sections in order of increase of their diameters. Largest circular ring whose outer diameter is equal to size of surface being illuminated is set-up last.
EFFECT: increased area of illuminated sections at one and the same sizes of solar reflectors.
FIELD: space engineering; temperature control systems of automatic spacecraft flying in near-earth orbits.
SUBSTANCE: proposed method includes removal of excessive heat from instruments through two first and two second evaporators interconnected in longitudinal direction; said evaporators are made in form of L-shaped adjustable thermal tubes. Removal of heat from condensers of these tubes is effected to first and to second radiators-emitters of U-shaped heat-conducting honeycomb unit located orthogonally relative to first ones. Inner surfaces of side radiators-emitters are provided with heat insulation and side radiators-emitters have edges projecting beyond boundaries of instrument container. Their inner surfaces are provided with heat-controlled coat. Temperature control system is provided with two instrument containers interconnected by their center honeycomb panels. Side radiators-emitters are located in parallel or orthogonal planes. Built in structure of each U-shaped honeycomb units are L-shaped thermal tubes in such position that their condensers are located in side radiators-emitters and evaporators are located in center honeycomb panel. System provides for narrow range of control of seats of instruments mounted on center honeycomb panels.
EFFECT: enhanced efficiency of temperature control; enhanced reliability of spacecraft; extended field of application.
6 cl, 6 dwg
FIELD: rocketry and space engineering; scientific and commercial fields.
SUBSTANCE: proposed method includes placing payloads on injection facility, launching the launch vehicle, separation of injection facility from launch vehicle and injection of injection facility into geocentric orbit where said payloads are separated from injection facility. Main payload is placed on injection facility directly of body of accompanying payload; this body combines its functions with functions of main load-bearing member of adapter system for placing the main payload. After separation of injection facility from launch vehicle, additional acceleration of injection facility is performed and injection facility is injected into reference orbit and then it is shifted to geocentric orbit where main and accompanying payloads are separated. Accompanying payload is separated from injection facility after main payload is at safe distance without waiting for complete turn of main payload. Spacecraft in facility injecting the artificial satellites into geocentric orbit are placed in succession on injection facility beginning with lower one. Main payload in form of one or several spacecraft is placed on body of lower spacecraft through separation device. Body of lower spacecraft combines its functions with functions of adapter load-bearing member for placing the main payload.
EFFECT: increased mass ratio of launch vehicle and injection facility; extended functional capabilities.
3 cl, 2 dwg