RU2506605C2 - Ranging method and device to determine coordinates of radiation source - Google Patents

Abstract

FIELD: measurement equipment.

SUBSTANCE: invention relates to the field of determination of location of radiation sources. The specified result is achieved by the fact that at least in three mutually distanced points of reception, levels of a radio signal are measured from the source of radiation with available energy characteristics, which characterise the value of signal attenuation in the distribution channel, then, by the value of this attenuation, the distance is calculated from the object of radiation to each of the receiving stations, and using the coordinate information on location of the receiving stations, they calculate coordinates of the object of radiation. The device to determine Cartesian coordinates of the source of radiation includes at each point of reception: a non-directed antenna sensor of a half-wave vibrator; a radio receiver with an analog-digital converter at the outlet; metres of energy or amplitude of the received signal; a calculator of the distance from the source of radiation and one that combines data at receiving stations, a calculator of coordinates of the source of radiation. Coordinates of the radiation source are calculated according to formulas given in the text of invention description.

EFFECT: detection of coordinates of location of a source of radiation of available intensity in passive mode under conditions of no mutual time synchronisation of receiving stations.

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Description

The technical field to which the invention relates:

The invention relates to the field of positioning by comparing in one coordinate system three or more found distances (G01S 19/00) using radio waves (G01S 005/02) and can be used to provide a solution to navigation problems in air traffic control systems, marine navigation systems , a rescue service for ships, ships, planes and other aircraft in distress. The prior art:

Existing range-finding methods for determining the location of radio emission objects are based on measuring the phase or time delay of the wavefront when it propagates from the radiation object to each of the passive receivers [1]. Such measurements can be made only by using an active request for radiation from the source in the presence of strict time or phase synchronization between the points of reception, which is a restriction on their use.

Another analogue of the invention is a differential-ranging method for determining the coordinates of a source of radio emission and a device that implements it [2]:

The invention relates to determining the coordinates of a source of radio emission (IRI) in space. SUMMARY OF THE INVENTION: planes containing a line of position of an IRI representing the intersection of two hyperbolic position surfaces corresponding to time-difference measurements are used as IRI position surfaces. The method is based on the reception of an IRI signal by four antennas, measuring three differences in the signal reception times of the IRI by the antennas forming the measuring bases, subsequent processing of the measurement results in order to calculate the values of the IRI position parameters and calculating the IRI coordinate as the intersection point of the three position planes. The proposed device contains four antennas, forming three pairs of measuring bases located in mismatched planes, three calculators of the position parameters of the IRI, the coordinate calculator of the IRI in the form of a block for solving a system of linear equations and an indication block. Achievable technical result is the provision of an unambiguous determination of the linear coordinates of the object. The disadvantages of this method and device also lie in the need for strict mutual time synchronization of the receiving points due to the need to measure the difference in the times of arrival of the signal at each of the receiving points.

The third analogue is a range-finding method for determining the location of a radio station by the difference in the arrival of a radio signal in time to reception points [3]. The invention relates to the field of direction finding technology and can be used in the rescue service of ships, ships, aircraft and other aircraft in distress. The purpose of the invention is improving the accuracy of determining the location of a working radio station. This goal is achieved by the fact that at least three points of reception located on one straight line, the measured moments of time of arrival of the radio signal of a working radio station t _a , t _b and t _c . Then, the delay time of the arrival of the radio signal to the other two points of reception relative to the third is determined. According to the delay time of the arrival of the radio signal to the receiving points, the distances traveled by the radio signal are calculated according to the formula

R _i = cΔt _i ,

where c is the speed of light, Δt _i is the delay time of the arrival of the radio signal at the receiving point. After that, the distances from the points of reception to the point of location of the radio station are calculated according to the formulas given in the text of the description of the invention. This method also does not allow location measurement in the absence of time synchronization between receiving points.

The prototype of the invention is a method for determining the location of aircraft and a system that implements it, described in [4]. Three pulsed radar stations are located on Earth, the coordinates of which are precisely known, and the aircraft are equipped with radio transponders. Three propagation times of τ ₁ , τ ₂ , and τ ₃ signals between ground stations and the aircraft and the corresponding distances R ₁ , R ₂ and R _{3 are} measured. At the Central processing point (CPO) determine the coordinates of the aircraft in a rectangular Cartesian coordinate system (figure 1). The system of equations connecting the Cartesian coordinates of the radio source and the measured distances in this case will have the following form:

;

;

;

;

. Угловое положение объектов наблюдения определяется азимутом α и углом места β. Этот способ требует организации радиоканала «запрос-ответ» и обеспечения взаимной временной синхронизации пунктов приема.The following arrangement of points of the system is accepted: points 1, 2, 3 - at the vertices of an equilateral triangle with a side equal to d, points 1 and 2 - on the X axis symmetrically relative to the beginning, point 3 - on the Y axis at a distance a from the origin

. The angular position of the observed objects is determined by the azimuth α and elevation angle β. This method requires the organization of a radio channel "request-response" and ensure mutual time synchronization of points of reception.

The invention:

The purpose of the invention is to provide a location determination of a source of a known radiation intensity in a passive mode in the absence of mutual time synchronization of reception points.

This goal is achieved by the fact that the proposed range-finding method for determining the coordinates of the location of the source of radio emission from the measurement data in at least three mutually distant from each other points of reception of radio signals, namely, that at the points of reception, the distances from the source of radio emission to each of the points of reception are determined and based on the obtained distances, the coordinates of the location of the source of radio emission are calculated, while the points of reception determine the intensity of the signal source, and then the magnitude of the signal intensities calculate the distance from the source of radio emission to each of the receiving points according to the amount of attenuation of the signal along the propagation path from the source of radio emission to the point of reception.

The measurement of distance by the magnitude of the signal intensity is an essential feature, since this measurement does not require mutual time synchronization of the receiving points and can be carried out in the passive mode of operation of the receiving points.

The goal is met by a device for determining the Cartesian coordinates of a radio emission source (FIG. 1), which includes three spatially spaced omnidirectional antennas such as a half-wave vibrator 1, 2 and 3; three radios 4, 5 and 6; three analog-to-digital converters 7, 8 and 9; three meters of signal energy 10, 11 and 12; three range calculators 13, 14 and 15 and a coordinate source transmitter of the radio emission 19. In this case, the antenna 1, the radio receiver 4, the analog-to-digital converter 7, the signal energy calculator 10 and the range calculator 13 are connected in series and form the first receiving device 16; antenna 2, radio 5, analog-to-digital converter 8, signal energy calculator 11 and range calculator 14 are connected in series and form a second receiving device 17; antenna 3, radio 6, analog-to-digital converter 9, signal energy calculator 12 and range calculator 15 are connected in series and form the third receiver 18. The first, second and third receivers are located in space so that they form the vertices of an equilateral triangle with a side equal to accommodation base d (fg.2). The outputs of the first, second and third receivers are connected to the corresponding inputs of the calculator of the Cartesian coordinates of the radio emission source 19.

The device operates as follows: the signals from the radio source received by each of the antennas 1, 2 and 3 are sequentially amplified in the respective receivers 4, 5 and 6; converted into digital form in analog-to-digital converters 7, 8 and 9. The resulting digital sequences are fed to the corresponding signal energy calculators 10, 11 and 12, which are digital matched filters. Digital sequences from the output of signal energy calculators 10, 11 and 12 are fed to the respective range calculators 13, 14 and 15, which determine the distances from the radio source to the corresponding radio receiver by calculating the ratio

where E _IZ is the known value of the signal energy of the radio source, S _APRM is the effective area of the antenna of the radio receiver, E _PRMi is the signal energy received by the i-th radio receiver, corresponding to the maximum response of the digital matched filter, G _0PRD is the gain of the antenna of the radio source.

The obtained digital values of the distances from the source of radio emission to the first R ₁ , second R ₂ and third R _{3 of the} receiving devices 16, 17 and 18 are fed to the calculator of the Cartesian coordinates of the radio emission source 19, which calculates the position of the signal source according to the results of these measurements using the formulas

Relationships (1) and (2) show that in order to determine the location of a source of radio emission of known intensity, it is necessary to know the gain of the antenna of the source of radio emission; the effective antenna area of each radio receiver and the signal energy received by each of the receiving devices. This in turn means that the set of distinctive features introduced is essential, i.e. the device meets the requirements of the purpose of the invention, namely, that to determine the location of the source of the radio emission in the passive mode, mutual time synchronization of the radio receivers is not necessary.

The processes of determining the signal source intensity and calculating the distance from the radio source to each of the receiving points from the value of these signal intensities, which were introduced into the range-finder method for determining the coordinates of the location of the radio emission source from the measurement data at at least three points of reception of radio signals mutually remote from each other, were not used in any of the signal intensities from known ranging methods for determining the location of objects. Such a set of distinctive features is absent in the analogues and in the prototype, which proves the conformity of the proposed method to the criterion of "novelty."

In turn, three signal energy meters 10, 11, and 12, introduced into the device for determining the Cartesian coordinates of the radio emission source; three distance calculators 13, 14 and 15 are also absent in the analogs and in the prototype, which proves the conformity of the proposed device to the criterion of "novelty."

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 tracked areas for improving range-finding systems, reflected in the scientific and technical literature, are associated with the use of phase or time information about the received measuring signals. This means that the claimed invention does not follow explicitly from the prior art, and therefore has an inventive step.

List of figures and drawings

Figure 1 presents the structural diagram of a device for determining the Cartesian coordinates of a radio emission source, where the numbers denote: 1, 2 and 3 - three spatially separated omnidirectional antennas such as a half-wave vibrator; 4, 5 and 6 - three radios; 7, 8 and 9 - three analog-to-digital converters; 10, 11 and 12 - three signal energy calculators; 13, 14 and 15 - three distance calculators; 16, 17 and 18 - the first, second and third receiving devices, respectively, and 19 - the transmitter of the coordinates of the source of radio emission.

Figure 2 presents a drawing of the location in space of the first (1), second (2) and third (3) receiving devices. In the same place, the point M denotes the object of radio emission, the coordinates of which must be determined.

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. Let us consider the possibility of technical implementation using the example of constructing an aerodrome system for determining the location of aircraft according to automatic dependent observations in the ADS-B broadcast mode. An aircraft equipped with an ADS-B system transmits its characteristics over the air every second over the entire route. In this case, the frequency, radiation power of the transmitters and the characteristics of the antennas located on board the aircraft are precisely known.

For an example implementation of the first, second and third receiving devices, you can use:

1. Omnidirectional antennas such as half-wave vibrator 1, 2 and 3 - Russian antenna company Radial (10 dBi). Description: http://adsbradar.ru/content/radial-1065-1134-mhz-antenna-vertikalnava-a10-1090

2. Radio receivers 4, 5 and 6 - include signal preamps, in this case they can be low-noise amplifiers at 1090 MHz from Kuhne electronic KU LNA 1090 (30 dB). Description: http://adsbradar.ru/KU-LNA-1090-A-TM-Super-Low-Noise-Amplifier-for-Avionics. Actually, the signal amplifiers and frequency converters are built for the dynamic range of the ADC and do not cause technical difficulties.

3. The market for analog-to-digital converters (7, 8 and 9) for the application in question is quite saturated.

4. The digital implementation of signal energy calculators (10, 11 and 12), range calculators (13, 14 and 15) and the coordinate calculator of the radio emission source (19) can be provided by microprocessor means in accordance with the algorithms described in the description of the invention.

Thus, the claimed invention is industrially applicable. It can be used in all industries where it is necessary to determine the location of sources of radio emission in space, such as marine ground and air radio navigation, topography, geological exploration, etc. It has advantages over the well-known ones associated with the lack of the need for temporary synchronization of reception points, which leads to it. technical and economic efficiency.

Literature.

1. B.C. Kondratiev, A.F. Kotov, L.N. Markov "Multiposition Radio Engineering Systems" M .: Radio and Communication, 1986, p.220-228.

2. Patent No. 2309420 RU, Application No. 2006103054/09, 02.02.2006, Military Space Academy named after A.F. Mozhaysky (RU), Publ. 10/27/2007.

3. Patent No. 2096800 RU, Reg. application number: 93051121 Basic codes of the IPC: G01S 005/02 Rogovoi V.F.

4. Radar tools for air defense systems of the 80s. - Electronics abroad, 1978, No. 2.

Claims (2)

1. The range-finding method for determining the coordinates of the location of the radio emission source according to the measurement data in at least three points of reception of radio signals mutually remote from each other, namely, that at the points of reception, the distances from the source of radio emission to each of the points of reception are determined and the coordinates are calculated from the obtained distances the location of the source of radio emission, characterized in that in passive mode in the absence of mutual time synchronization of reception points at reception points from eryayut intensity of the source as the signal energy of the signal, determined by the maximum response of the matched filter, and then the value of the signal intensities calculated distance from the radiation source to each of the receiving points on the magnitude of the signal attenuation along the propagation path from the radiation source to receiving point. 2. A device for determining the Cartesian coordinates of a source of radio emission, containing three spatially spaced omnidirectional antennas such as a half-wave vibrator; three radios; three analog-to-digital converters and a coordinate source calculator of the radio emission source, wherein the output of each omnidirectional antenna is connected to the input of the corresponding radio receiver, and the output of each radio receiver is connected to the input of the corresponding analog-to-digital converter, and the antennas with radio receivers and analog-to-digital converters are located in such a space so that they form the vertices of an equilateral triangle with a side equal to the placement base, characterized in that in the device Three signal energy calculators, made in the form of digital matched filters, and three range calculators are included, the outputs of the analog-to-digital converters of the radio receivers are connected to the inputs of the corresponding signal energy calculators, and the outputs of the signal energy calculators are connected to the inputs of the corresponding range calculators, the output of each of the calculators range connected to the corresponding input of the transmitter coordinates of the source of radio emission.

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