RU2558640C2 - Multiplicative difference-relative method for determination of coordinates of position of pulsed radio-frequency source - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to radio engineering, particularly to radio monitoring systems for determining the position of pulsed radio-frequency sources. The method is based on using measurements of values of the time of arrival of signals at three radio monitoring stations, two which are fixed and one (or two) are mobile. The measured values of the time of arrival are used to calculate the propagation time of signals from the radio-frequency source. A 5×5 Cayley-Menger determinant is formed and opened to obtain the complete quartic equation. The numerical solution of said equation yields the values of the distance from the source to the stations and, based on the proportional relationship between the ratios of the distance from the station to the radio-frequency source and corresponding ratios of values of the delay of pulsed signals, enables to obtain all combinations of multiplicative differences of said ratios. The multiplicative differences of the ratios are processed using a dichotomous method or accelerated descent methods.

EFFECT: determining spatial coordinates of radio-frequency sources using three fixed stations.

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Description

The invention relates to the field of radio engineering, and in particular to radio monitoring systems for determining the location coordinates of radio emission sources (IRI), information about which is not available in the database (for example, the state radio frequency service or the state service for monitoring communications). The invention can be used in the search for the location of unauthorized communications.

Known methods for determining the coordinates of the IRI, in which passive direction finders are used in an amount of at least three, the center of gravity of the region of intersection of the revealed azimuths of which at the wave arrival front is taken as the location estimate. The basic principles of operation of such direction finders are amplitude, phase, and interferometric [1, 2]. Widely used is the amplitude direction finding method, in which an antenna system is used that has a radiation pattern with a pronounced maximum of the main lobe and minimal rear and side lobes. Such antenna systems include, for example, log-periodic or antennas having a cardioid characteristic, etc. With the amplitude method, the position of the antenna is reached by mechanical rotation, at which the output signal has a maximum value. This direction is taken as a direction to Iran. The disadvantages of most direction finders include a high degree of complexity of antenna systems, switching devices and the presence of multi-channel radios, as well as the need for high-speed information processing systems.

The presence in the federal districts of the state radio frequency service interconnected through a central point of an extensive network of radio monitoring posts equipped with means for receiving radio signals, measuring and processing their parameters, allows you to supplement their functions and tasks of determining the coordinates of the location of those IRI, information about which is not available in the database, without resorting to the use of complex and expensive direction finders.

(сочетаний из N по 4) на основании обратно пропорциональной зависимости отношений расстояний от поста до источника радиоизлучения и соответствующих им разностей уровней сигналов, выраженных в дБ, составляют три уравнения, каждое из которых описывает окружность равных отношений, по параметрам двух любых пар которых и определяют текущее среднее значение широты и долготы местоположения источника радиоизлучения. Недостатком этого способа является большое количество стационарных постов радиоконтроля.The known method [3], in which N, at least four stationary radio monitoring posts located on more than one straight line are used to determine the coordinates of the IRI location, one of which is taken as the base, connecting with the rest of the N-1 posts by communication lines, at all posts carry out quasi-synchronous scanning at given fixed tuning frequencies, average the measured values of signal levels at each of the scanned frequencies, and then at the base station for each of the combinations

(combinations of N by 4) based on the inversely proportional relationship between the distance from the post to the radio source and the corresponding differences in signal levels, expressed in dB, are three equations, each of which describes the circle of equal relations, according to the parameters of any two pairs of which determine the current average of the latitude and longitude of the location of the source of the radio emission. The disadvantage of this method is the large number of stationary monitoring posts.

Known methods and devices for direction finding [4, 5], which can be used for the purpose of determining coordinates.

The method [4] is based on the reception of signals by three antennas forming two pairs of measuring bases, measuring the differences in the arrival time of the IRI signals and deterministic calculations of the desired coordinates.

The disadvantages of the method include:

1) A large number of antennas.

2) The method is not focused on the use of radio monitoring posts.

3) Measuring bases for calculating the difference in the arrival times of the IRI signals by antenna pairs significantly limit the separation of these antennas, not to mention the inappropriateness and great technical complexity of the implementation of the method.

An exploded difference-range direction finder [5], consisting of two peripheral points (PP), a central point (CPU) and a single time system, aims to unload the communication channel between the points. The peripheral points are intended for receiving, storing, processing signals and transmitting signal fragments to the CPU, on which the difference of the signal arrival time is calculated. The single time system uses a chronizer, which is a keeper of the current time scale (hours) tied to the single time scale, designed to bind the signal level values recorded in the memory to the reception time value.

This direction finder has the following disadvantages:

1) Not adapted to the radio control points used in the branches of the federal districts of the state radio frequency service or the state service for supervision of communications.

2) A large number of specialized direction finding (but not radio monitoring) posts.

3) Unreasonable and unrevealed (at least until the functional diagram) application of a single time system on a CPU and time clocks on a PC synchronized with a single time system.

4) The need for radio channels with high bandwidth (up to 625 Mbaud) for the transmission of even fragments of signals from PP1 and PP2 to the CPU.

5) To organize a radio channel, radio transmitting devices and obtaining permission for their operation in certain operating conditions are required.

The known differential-ranging method for determining the coordinates of the source of radio emission and the device that implements it [6].

A method based on the reception of IRI signals by four antennas forming three independent measuring bases at the separated points A, B, C, D so that the volume of the figure formed from these points is greater than zero (V _{A, B, C, D} > 0). The signal is simultaneously received at all antennas, three independent time differences Δt _AC , Δt _BC , Δt _DC of signal reception by pairs of antennas forming measuring antenna bases (AC), (BC) and (DC) are measured. From the measured time differences, the distance differences from the IRI to the pairs of points (A, C), (B, C), (D, C) are calculated for the k-th triple of antennas located at points A, B, C with k = 1, B, C, D for k = 2, D, C, A for k = 3, using the measured distance differences, calculate the angle γ _k characterizing the angular position of the IRI Ω _k , k = 1, 2, 3 relative to the corresponding measurement base, and coordinates of the point F _k, belonging to the k-th plane IRI position calculating IRI desired coordinates as the coordinates of the point of intersection of three planes IRI position Ω _{k, k} = 1, 2, 3, each I of which is characterized by the location coordinates of the points k-th antennas triples and calculated values of the angle γ _k and the coordinates of the point F _k, displaying results of calculation of IRI coordinates in a predetermined format.

This method is closer to the claimed, but also has a number of significant disadvantages:

1) The complexity of the practical implementation of the method due to the lack of the ability to measure differences in the reception times of the IRI signal only by antennas (there are no measuring radios in the block diagram).

2) The need to reduce the IRI signals from the EMD antennas spaced apart at the optimum distance to 0.6-0.7 R according to [2] at one point, which is not economically feasible to implement.

3) Two-input meters are used to measure the difference in the time of signal reception directly from the antennas.

4) The complexity of the technical implementation, due to the large number of different calculators.

5) Uncertainty in the construction of the position surface in the form of a plane perpendicular to the antenna plane, since the antennas at points A, B, C, D are not located in the same plane, as evidenced by the condition V _{A, B, C, D} > 0 in the formula invention.

Closest to the claimed is a rangefinder-differential-rangefinder method for determining the coordinates of the source of radio emission and the device that implements it [7], adopted as a prototype.

The method is based on the reception of a signal by three antennas, measuring the values of two differences in the signal reception time of the IRI antennas, measuring two values of the power flux density of the IRI signal, subsequent processing of the measurement results in order to calculate the coordinates of the point through which the Iranian position line passes.

This method involves the following operations:

- have three antennas at the vertices of the triangle ABC;

- receive a signal on all three antennas;

- measure two time differences Δt _AC and Δt _{BC of the} reception of the IRI signal by the antennas;

- measure the density of the power flux P ₁ and P _{2 the} signal at the locations of the antennas 1 and 2;

- calculate the values of the differences of the distances from the IRI to pairs of antennas using the expressions Δr _AC = CΔt _AC , Δr _BC = CΔt _BC , Δr _AB = Δr _AC -Δr _BC , where C is the propagation velocity of the electromagnetic wave;

- calculate the coordinates according to the formula obtained.

In accordance with [7], the device that implements the method includes:

- three antennas;

- two time difference meters;

- two power flux density meters;

- computing unit;

- display unit.

The prototype has the following disadvantages:

1) The practical complexity of the method due to the lack of the ability to measure differences in the reception times of the IRI signal only by antennas (there are no measuring radios in the block diagram).

2) The need to reduce the IRI signals from antennas spaced several kilometers into one point for measurement by two-input meters, which is a significant and not solved by the patent authors problem.

3) There is no possibility of using the measurement results in various combinations for their statistical processing in order to improve the accuracy of determining the coordinates of the location of the IRI.

4) It is not adapted to the equipment of radio monitoring posts (two time difference meters, two power flux density meters, a computing unit, an indication unit) are redundant, which are available in the branches of the federal districts of the RF radio frequency service, and therefore cannot be used there.

точки F, принадлежащей линии пеленга ИРИ, с использованием выражений:5) Two-sheeted hyperboloids of rotation corresponding to two time-difference measurements and a sphere whose parameters are determined when processing power flux-density values at the points of placement of two receiving antennas are used as IRI position surfaces. These complex nonlinear expressions give rise to coordinate determination errors. In particular, the calculation of coordinates

point F, belonging to the line of the bearing IRI, using the expressions:

leads to the appearance of a singularity error (when the denominator can be close to zero).

The aim of the present invention is to develop a method for determining the coordinates of the location of the IRI, devoid of the disadvantages of the prototype of the three radio monitoring posts, which will allow this method to be applied in all branches of the federal districts of the Radio Frequency Service of the Russian Federation.

This goal is achieved using the characteristics indicated in the claims:

и

мультипликативных функций, представляющих сочетания, взятые по два и по три, из вычисленных

парных сочетаний (М+2) разностей отношений расстояний, рассчитанных от точек измерения до местоположения искомого ИРИ по заданным его координатам, и вычисленных

парных сочетаний (М+2) отношений соответствующих измеренных величин запаздывания прихода сигналов, расстояния от точек измерения до источника получают при этом для заданных из известного диапазона значений широт и долгот местоположения искомого ИРИ, изменяют дихотомически или методом наискорейшего спуска последовательно каждый из параметров местоположения искомого источника радиоизлучения при неизменном значении другого и находят точки экстремумов

и точки перегиба

мультипликативных функций с усреднением и последовательной фиксацией каждого искомого параметра местоположения источника в этих точках, как окончательного. Перед проведением измерений и вычислений координат местоположения искомого ИРИ выполняют калибровку измерителей на постах.A multiplicative difference-relative method for determining the location coordinates of a pulsed radio source, based on measuring the delay values of radio signals at the assigned frequencies at several points in space by radio receivers, characterized in that a pre-calibrated mobile radio monitoring post is used as the base one to move the moments of arrival of signals along M≥1 points of a nonlinear trajectory, and two driven identical stationary stations that radio monitoring, connected by communication lines with the base, the measured values of the moments of arrival of the signals from which are transmitted to the base post, where the difference in the time of arrival of the signals is calculated, form the Cayley-Menger determinant with a dimension of 5 × 5, and form on its basis a complete fourth-degree equation with respect to one of the unknowns the distance from the source to the post, it calculates the distances to other posts and the distance ratios, equivalent to the ratios of the propagation time of the signals to the posts, are

and

multiplicative functions representing combinations taken in two and three from calculated

paired combinations (M + 2) of differences of the distance relations calculated from the measurement points to the location of the desired IRI at its given coordinates, and calculated

pair combinations (M + 2) of the ratios of the corresponding measured values of the signal arrival delay, the distance from the measurement points to the source are obtained for each of the location parameters of the desired source dichotomously or by the method of steepest descent from the specified range of latitudes and longitudes of the location of the desired IRI; radio emissions at a constant value of another and find the points of extrema

and inflection points

multiplicative functions with averaging and sequential fixing of each sought source location parameter at these points as final. Before making measurements and calculating the coordinates of the location of the desired IRI, calibrate the meters at the posts.

. Затем вычисляют парные отношения этих расстояний

. Эти отношения позволяют исключить зависимость вычисления координат местоположения от мощности ИРИ. Полученные отношения сравнивают путем вычитания с измеренными отношениями величин запаздывания прихода сигналов или с соответствующими им расстояниями от ИРИ до постов

, где r_a, r_b, r_c - фактические расстояния до постов, указанные на фиг. 5.Calibration of the meter of the time of arrival of signals at the posts is performed using reference RES with known signal parameters and location coordinates. Each reference RES should be in the EMD zone of all three posts. The number of reference RES and the distribution in the EMD zone of the posts should be sufficient to ensure a given calibration accuracy both in distance and azimuth relative to the posts. The determination of coordinates is based on the conceptual refusal to use any complex IRI position lines, for example, parabolas, hyperbolas, Apollonius Pergsky circles, Cassini ovals, rotation hyperboloids, and others, and the use of a universal numerical method for sequentially determining IRI location parameters. At the same time, instead of physical quantities (distances, delays in the arrival of radio signals to the points of their reception), it is proposed to use multiplicative differences in the ratios of these physical quantities, using the criterion of the minimum differences in the ratios of the distances from the IRI location to the radio monitoring posts and the corresponding ratios of the signal propagation times. Coordinates can be calculated using the dichotomy method, for example, the method of bitwise balancing. For its use, a priori, the ranges of D values of the sought quantities must be known. These ranges are usually known based on the parameters of the general electromagnetic accessibility zone of the three radio monitoring stations used. In accordance with the bitwise balancing algorithm, the average value from the range D is initially set to the value of the determined quantity (for example, latitude) for a fixed, but lying in the known ranges of values, longitude. Calculate the distance from the i-th location of the IRI to each j-th post,

. Then the pair relations of these distances are calculated

. These relationships make it possible to eliminate the dependence of the calculation of location coordinates on the power of the IRI. The obtained relations are compared by subtracting from the measured ratios the values of the delay in the arrival of signals or with the corresponding distances from the IRI to the posts

where r_a, r_b, r_c - the actual distances to the posts indicated in FIG. 5.

For example, for posts A and B, this difference is defined as f _{1abi, ab} = (n _abi -n _ab ). For B and C - as f _{1bci, bc} = (n _bci -n _bc ), etc.

, где m - количество итераций.If the difference in relationship is less than zero, then 1/4 of the range is added to the original latitude value. Otherwise, 1/4 of the range of its value is subtracted from the original latitude value. Then again calculate the distances to the posts and evaluate the results of the comparison, as described above. In this case, 1/8 of the range is added (or subtracted), then 1/16 of the range, etc. Such iterations continue until the result of the comparison is in absolute value less than a predetermined value of the sampling error of each location parameter

where m is the number of iterations.

After that, the obtained parameter value is fixed. Then, in the same way, the longitude value is calculated at the latitude found. The minimum of any of the differences indicates the location of the IRI at the point with the selected coordinates. But since the coordinates of the IRI are perpendicular to the base line, each of the individual differences f _{1abi, ab} , f _{1bci, bc} , f _{1cai, ca} will have a minimum value when the IRI is located on both sides of the bases. There is ambiguity in determining the location of the IRI. The ambiguity is removed by finding extrema or inflection points of the multiplicative functions of the differences of relations. Since the method considers two physical quantities (see above), they take the differences in the ratios of the distances from the source of radio emissions to the points of their reception and the corresponding values of the propagation time of the signals. Since the signal arrival time meters are located according to the method at all posts, there will be three such differences: f _{1abi, ab} = (n _abi -n _ab ), f _{1bci, bc} = (n _bci -n _bc ), f _{1cai, ca} = (n _cai -n _ca ).

Based on these three types of relationship differences, to uniquely determine the coordinates of the location of the IRI are multiplicative functions that include two or three difference relationships.

.Examples of multiplicative functions involving two difference relations: f _2abc = The total number of such functions is

.

.An example of multiplicative functions, including three differences in the relations of functions: f _3abc = f _{1abi, ab} f _{1bci, bc} f _{1aci, ac} . The total number of such functions is

.

In FIG. 1 shows relationship differences for three types of relationship differences; FIG. 2 - three paired multiplicative functions, FIG. 3 - multiplicative function of three differences of relations.

. Выражая время запаздывания прихода сигналов T_c, T_b, T_a через соответствующие проходимые сигналами расстояния, получим

, или в другом виде:

, где С - скорость распространения электромагнитной волны.From the timestamps of the arrival of IRI signals to the synchronized signals of the reference RES, the measuring instruments of the moments of time of arrival [8] of all three posts at the leading post calculate the difference in the delay time of the signals of the desired RES

. Expressing the time delay of arrival of the signals T _c , T _b , T _a through the corresponding distances traveled by the signals, we obtain

, or in another form:

where C is the propagation velocity of the electromagnetic wave.

From the obtained relations we express the distances: r _a and r _{b in} terms of r _c (other substitutions can be made): r _a = r _c + Δr _ca , r _b = r _c -Δr _bc .

To calculate the unknown distance r _{c, they} compose and open the Cayley-Menger determinant of 5 × 5 dimension, which is one greater than the number of vertices of the volume of the four-vertex simplex figure described in FIG. 5. Since the projection volume of this figure onto the plane is zero, the Cayley-Menger determinant in accordance with [9] is represented in the form

In this determinant, in accordance with the explanatory FIG. 5 through a, b and c marked base (distance between posts). Opening the determinant, we obtain:

The determinant (1), taking into account the introduced ratios of the distances r _a and r _b, will represent the complete 4th degree equation with respect to the unknown distance r _c , having the form:

Where:

Equation (2) with respect to r _{c is} solved numerically. After that, the distances r _a and r _{b are also found} . And then they determine the relations of these distances, compose and solve the multiplicative functions of the differences of relations. As a result of solving the latter and averaging, the desired coordinates of the Iranian location are obtained.

A technical implementation of the method, adequate [10], is shown in FIG. 4, which shows three identical radio monitoring posts - RCP A, RCP B and RSCPS, containing:

1. Omni-directional antennas 1, 6, 11;

2. Scanning radios (RP) 2, 7, 12;

3. Measuring the values of the delay of signals (IVS) 3, 8, 13;

4. Computers 4, 9, 14;

5. Communication devices 5,10,15.

The method involves the following operations:

1) Calibrate the meter of the delay value of arrival to the signal posts (IWS) using an array of reference RES with known signal parameters and location coordinates. Each reference RES should be in the EMD zone of all three posts. The number of reference RES and the distribution in the EMD zone of the posts should be sufficient to ensure a given calibration accuracy both in distance and azimuth relative to the posts.

2) At each station, the values of the times of arrival of the IRI signals are measured using the appropriate meter using non-directional antennas of the station, while tuning the receiver to the given fixed frequencies. The results are entered into the database of your computer.

3) Information received in paragraphs. 1 and 2, are sent over the communication channel of the communication device from the slave computers to the master.

4) Make up the Cayley-Menger determinant of dimension 5 × 5.

5) The Cayley-Menger determinant is disclosed, while obtaining the complete fourth-degree equation with respect to one unknown.

6) The numerical method is used to determine the distance to the fourth degree using the complete equation, and then the magnitude and ratio of the arrival delay of signals from the IRI based on the arrival times of signals measured by meters [8].

парных произведений разностей отношений расстояний стационарных постов радиоконтроля до местоположения источника радиоизлучения, соответствующих отношений величин запаздывания сигналов источника, эквивалентных расстояниям от искомого источника радиоизлучения до стационарных постов, и еще составляют

мультипликативных функций разностей отношений тех же расстояний и отношений величин запаздывания прихода сигналов, взятых по три.7) Make up

paired products of the differences in the ratios of the distances of the stationary posts of the radio monitoring to the location of the source of radio emission, the corresponding ratios of the delay values of the source signals, equivalent to the distances from the desired source of radio emission to the stationary posts, and still make up

multiplicative functions of differences in the ratios of the same distances and the ratios of the delay values of the arrival of signals taken in three.

8) The latitude and longitude of the IRI location corresponding to the points of extrema, as well as the inflection points of all the multiplicative functions compiled in paragraph 7, are calculated dichotomously or by the method of steepest descent, after fixing, after averaging, each sought source location parameter at these points is final.

Below is a table of the relative increase in statistics (in times) for a different number Μ measuring points of mobile posts.

The table shows that the method gives an increase in statistics compared to the prototype 165 times.

In the proposed method, the disadvantages of the prototype are eliminated:

1) Any complex equations of the IRI location lines with hidden singularity errors hidden in them are excluded. In the proposed method, the multiplicative functions of the differences in the ratios of the final values (distances and delay values of the arrival of signals) are smooth and do not create singular errors.

2) The determination of the coordinates of the location of the IRI is carried out by radio monitoring posts, and not by means far from their practical implementation.

3) The method in connection with the use of multiplicative functions provides the ability to use the measurement results in various combinations, which allows to increase statistics and improve the accuracy of determining coordinates.

The method is more versatile in comparison with the known, easily implemented and devoid of the disadvantages of the prototype. Distinctive features of the method are not identified either in analogues or in the prototype, which indicates the presence in the proposed invention of signs of novelty and the corresponding level of inventiveness.

Literature

1. Korneev I.V., Lentsman V.L. and others. Theory and practice of state regulation of the use of radio frequencies and RES civilian applications.

 The collection of materials of continuing education courses for specialists of radio frequency centers of federal districts. Book 2. - SPb .: SPbSUT. 2003.

2. Lipatnikov V.A., Solomatin A.I., Terentyev A.V. Direction finding. Theory and practice. SPb .: YOU, 2006 .-- 356 p.

3. A method for determining the location coordinates of radio emission sources. Application No. 2009138071, publ. 04/20/2011 B.I. No. 11. Authors: Loginov Yu.I., Ekimov OB, Rudakov RN

4. Difference-range measuring method of direction finding of a source of radio emission. RF patent №2325666 C2. Authors: Saibel A.G., Sidorov P.A.

5. Diversity differential range finder direction finder. RF patent No. 2382378, C1. Authors: Ivasenko A.V., Saibel A.G., Khokhlov P.Yu.

6. Difference-range measuring method for determining the coordinates of the source of radio emission and the device realizing it. RF patent No. 2309420. Authors: Saibel A.G., Grishin P.S.

7. Rangefinder-difference-rangefinder method for determining the coordinates of the source of radio emission and the device that implements it. RF patent No. 2363010, C2, publ. 10.27.2007 Authors: Saibel A.G., Weigel K.I.

8. Determining the coordinates of the location of radiation sources during radio monitoring. Proceedings of the 9th international symposium EMC. - 2011. Authors: Loginov Yu.I., Ekimov OB, Antipin BM

9. Vladimirov Yu.S. Space - time: explicit and hidden dimensions. Ed. 2nd, rev. and add. - M.: Book House "LIBROCOM", 2010, 208 p.

10. Rangefinder-difference-rangefinder method for determining the coordinates of the location of the source of radio emission and the device that implements it. Application No. 20111134103/07, publ. 02/28/2013 Authors: Loginov Yu.I., Ekimov O. B., Antipin B. M., Gritsenko A. A., Pavlov V. N., Portnago L. B.

Claims (1)

A multiplicative difference-relative method for determining the location coordinates of a pulsed radio source, based on measuring delay values of radio signals at the assigned frequencies at several points in space by radio receivers, characterized in that a pre-calibrated mobile radio monitoring post is used as a base for measuring the moments of arrival of signals, moving it along M≥1 points of a nonlinear trajectory, and two driven identical stationary stations Iokontrol, connected by communication lines with the base, the measured values of the moments of time of arrival of signals from which are transmitted to the base post, where the difference of the time of arrival of signals is calculated, form a Cayley-Menger determinant of 5 × 5 dimension, make on its basis a complete fourth-degree equation with respect to one of the unknowns the distance from the source to the post, it calculates the distances to other posts and the distance ratios, equivalent to the ratios of the propagation time of the signals to the posts, are

and

multiplicative functions representing combinations taken in two and three from calculated

paired combinations (M + 2) of differences of the distance relations calculated from the measurement points to the location of the desired IRI at its given coordinates, and calculated

paired combinations (M + 2) of the ratios of the corresponding delay values of the signal arrival, the distance from the measurement points to the source is obtained for the given coordinates of the location of the desired IRI, dichotomously or by the method of steepest descent, each of the location parameters of the desired radio emission source at a constant value of the other and find extreme points

and inflection points

multiplicative functions with averaging and sequential fixing of each sought source location parameter at these points as final.

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