RU2558638C2 - Multiplicative difference-relative method for fixed-mobile determination of coordinates of position of 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 radio-frequency sources. The method is based on comparing ratios of distances from measurement points to the position of the radio-frequency source and inverse ratios of measured signal strength values. To this end, multiplicative functions of differences of said ratios are constructed. Said functions are processed using a dichotomous method which is based on the principle of consecutive determination of parameters of the position of the radio-frequency source.

EFFECT: determining spatial coordinates of radio-frequency sources by measuring the signal strength thereof using two fixed radio monitoring stations and one mobile radio monitoring station at M points (first version) or two mobile radio monitoring stations (second version) at M1 and M2 points of the location thereof with independent movement on a nonlinear path without employing position line equations.

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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 of radio emission sources (IRI), information about which is not in the database (for example, state radio frequency services or state communication supervision services). The invention can be used in the search for the location of unauthorized means of radio communication, as possible sources of communication interference.

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]. Their disadvantages 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 location of those IRI, information about which is not available in the database, without resorting to use complex and expensive direction finders. Of the known methods, the closest analogue (prototype) of the proposed method according to the technical essence is the method [3], which consists in receiving signals from radio sources in the frequency band ΔF moving in space meter. When moving the meter, signal levels are measured at N (Ν≥4) points, Ν-1 signal level ratios are successively calculated, Ν-1 circular position lines are constructed from the calculated ratios and the coordinates of the radio emission sources are determined as the intersection point of Ν-1 circular position lines. To increase the reliability of the location using statistics.

The main disadvantages of the prototype:

1. Algorithmic inconsistency and incompleteness of its implementation in time. Indeed, the statement that the coordinates of the sources of radio emission are found as the intersection points of Ν-1 (Ν≥4) of the circular position lines contradicts the need to refine these coordinates by statistical means. Since N in the claims is not limited from above, the coordinates of the IRI as the coordinates of the intersection point of an unlimited number of circular position lines will be determined with unlimited high accuracy. And, therefore, they do not need statistical refinement. But, if it is argued that a statistical specification of the location is necessary, then the possibility of crossing at one point an unlimited number of circular position lines is denied. And the latter is closer to reality, since there are no instruments and methods of measurement with unlimited high accuracy.

2. The fundamental difficulty of finding the coordinates of the intersection point Ν-1 (Ν≥4) of circular position lines by directly solving the system of equations describing them. Indeed, according to [4, p. 66] the general equation of a circle in Cartesian rectangular coordinates has the form:

And at the same time, “all circles passing through real or imaginary intersection points of two circles are determined by the equation:

where λ is the parameter. "

Let circles be given by the equations:

This system of three equations of any circles, including Apollonius, which was mentioned in [3], has one solution, that is, circles intersect at one point only if the determinant of the system is zero. And this is possible according to the source [4, p. 66], if one of the three equations is obtained from the other two in the indicated manner. Moreover, the coefficients of this derivative equation, let it be the Scd equation for definiteness, should be defined as:

A3 = (Α1 + λA2) / (1 + λ), B3 = (B1 + λB2) / (1 + λ), C3 = (C1 + λC2) / (1 + λ).

The determinant of such a system

indeed, it is equal to zero, and therefore, the third circle can pass through the intersection point of the first two circles only with a strictly defined connection with them.

The previous statement is also supported by the statement based on the fact that arcs of circles in the neighborhood of the point of their intersection (or tangent to circles at this point) can be considered as three intersecting lines. In this regard, according to [4, p. 59, p. G] statement: “In order for the three lines A1x + B1y + C1 = 0, A2x + B2u + C2 = 0, A3x + B3y + C3 = 0 to intersect at one point or be parallel, it is necessary and sufficient that

those. so that the left-hand sides of the equations are linearly dependent, ”it really reinforces the previous statement. The solution of the system of equations of three circles without imposing these conditions can be achieved, but only on other principles, one of which, as the simplest, is proposed by the authors of this application;

3. The number of measurement points for signal levels N≥4, which is redundant to obtain a single reference coordinate location.

4. The presence of the singularity of circular position lines (Apollonius of Perga circles) at close values of signal levels at the points of measurement, leading to a large error in determining the coordinates of the location of the IRI.

5. The prototype does not allow to determine the coordinates of the location of the IRI in space.

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) обратных отношений соответствующих измеренных величин уровней сигналов источника, дихотомически или методом наискорейшего спуска изменяют значение каждого из параметров местоположения ИРИ при неизменных значениях двух других и находят точки экстремумов

парных мультипликативных функций и точки перегиба

мультипликативных функций, взятых по три, фиксируя после N кратного

усреднения каждый найденный в этих точках параметр местоположения источника, как окончательный.The aim of the present invention is to develop a method for determining location coordinates at existing radio monitoring posts of the Radio Frequency Service of the Russian Federation, which eliminated the disadvantages of the prototype. This goal is achieved using the characteristics indicated in the claims: Multiplicative difference-relative method of a stationary-mobile determination of the coordinates of the location of a radio emission source, based on measuring signal levels of a radio emission source (IRI) at several points in space that are not lying on one straight line by scanning radio receivers moving in space, characterized in that two stationary monitoring posts are used to measure the signal levels of the IRI, and a mobile one the radio monitoring post is used as a base, connected to stationary posts by communication lines and moved along Μ≥1 points, at the last

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 inverse ratios of the corresponding measured values of the source signal levels, dichotomously or by the method of steepest descent, change the value of each of the IRI location parameters at constant values of the other two and find the points of extrema

paired multiplicative functions and inflection points

multiplicative functions taken in three, fixing after N multiple

averaging each source location parameter found at these points as final.

Затем вычисляют парные отношения этих расстояний

Эти отношения позволяют исключить зависимость вычисления координат местоположения от мощности ИРИ. Полученные отношения сравнивают с обратными отношениями уровней сигналов:The method is based on the principle of sequentially determining the parameters of the IRI location: latitude - Xi, longitude - Yi and height Zi according to the criterion of the minimum difference in the ratios of the distances of the IRI location to each of the three measurement points and the corresponding inverse relations of the signal levels measured at these points. The coordinates can be calculated by any of the known numerical methods: either by the linear method of successive approximation, or by the steepest descent method, or by the method of dichotomy, for example, by 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 electromagnetic accessibility zone of the used mobile monitoring posts. In accordance with the bitwise balancing algorithm, the average value from the range D is initially set to the value of the determined parameter (for example, latitude) for fixed, but lying in known ranges of values of longitude and height. Calculate the distance from the i-th location of the IRI to each j-th measurement point (j≤3),

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 resulting relationships are compared with the inverse ratios of signal levels:

путем вычитания.

by subtraction.

где m - количество итераций. На рис. 1 показано изменение этих функций для всех трех пар точек измерения при последовательном, равномерно-ступенчатом (для наглядности) поиске. После этого фиксируют полученное значение параметра. Затем аналогично вычисляют значение долготы при найденной широте, а затем и высоты. Отметим, что данный способ для одной пары точек измерения может иметь неоднозначность результата. Устраняют ее путем нахождения экстремумов для каждой из трех функций парных произведений разностей отношений (для каждой из двух пар точек измерений), например, 1,2 и 2,3: F_212.23=(n_12i-n₂₁)(n_23i-n₃₂), 1,2 и 3,1 - F_212.31=(n_12i-n₂₁)(n_13i-n₃₁), 2,3 и 3,1 - F_223.31=(n_23i-n₃₂)(n_13i-n₃₁) и точки перегиба функции произведения трех разностей отношений для точек измерения 1,2 и 3 F₃₁₂₃=(n_12i-n₂₁)(n_23i-n₃₂)(n_31i-n₁₃). На фиг. 1 показаны зависимости разностей отношений для каждой пары точек измерения, на фиг. 2 - для произведения двух пар точек измерения, фиг. 3 - произведение разностей отношений для трех пар точек.For example, for measurement points 1 and 2, this difference is defined as F ₁₁₂ = (n _12i -n ₂₁ ). For 2 and 3 - as F ₁₂₃ = (n _23i -n ₃₂ ), etc. If the difference in the relations is less than zero, then 1/4 of the range is added to the initial value of the determined parameter (latitude). Otherwise, 1/4 of the range of its value is subtracted from the initial value of the determined parameter (latitude). 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. In fig. Figure 1 shows the change in these functions for all three pairs of measurement points in a sequential, uniformly-stepped (for clarity) search. After that, the obtained parameter value is fixed. Then, similarly calculate the value of longitude at the found latitude, and then the height. Note that this method for one pair of measurement points may have an ambiguous result. Eliminate it by finding extrema for each of the three functions of the paired products of the difference of the relations (for each of the two pairs of measurement points), for example, 1,2 and 2,3: F _212.23 = (n _12i -n ₂₁ ) (n _23i -n ₃₂ ), 1,2 and 3,1 - F _212.31 = (n _12i -n ₂₁ ) (n _13i -n ₃₁ ), 2,3 and 3,1 - F _223.31 = (n _23i -n ₃₂ ) (n _13i - n ₃₁ ) and the inflection points of the product function of the three difference relations for the measurement points 1,2 and 3 F ₃₁₂₃ = (n _12i -n ₂₁ ) (n _23i -n ₃₂ ) (n _31i -n ₁₃ ). In FIG. 1 shows dependencies of relationship differences for each pair of measurement points, FIG. 2 - for the product of two pairs of measurement points, FIG. 3 - the product of the differences of relations for three pairs of points.

The parameter values obtained at all extreme points and inflection points are averaged and taken as final.

Algorithmically, the method involves the following operations:

1. Measure at least three points, including points of the trajectory of the mobile monitoring post, not lying on one straight line, the signal levels of the IRI, rebuilding the scanning receiver of the posts to the carrier frequencies and storing the coordinates of the level measurement points in the database.

2. The measured values of the levels are transmitted via communication lines to the base station, where:

1) Calculate the ratios of the measured levels of the IRI signals and the reciprocal of the ratios of the corresponding distances from the measurement points to the possible location of the IRI.

парных мультипликативных функций разности отношений расстояний от точек измерения уровней до возможного местоположения ИРИ и соответствующих обратных отношений измеренных уровней а также

мультипликативных уравнений для всех точек измерения уровней, взятых по три.2) Make up

paired multiplicative functions of the difference in the relations of distances from the points of level measurement to the possible location of the IRI and the corresponding inverse relations of the measured levels as well

multiplicative equations for all points of measurement of levels taken in three.

3) Two coordinate parameters (for example, longitude and height) are set from the estimated coordinate range of the possible location of the IRI, and one of the coordinate parameters (for example, latitude) is dichotomously changed and the possible distance of the IRI to each of the points of the measurements is calculated, until each of the three pairwise multiplicative functions with a given error reaches an extreme value, and the multiplicative functions for all points of level measurement, taken in three, do not reach inflection points.

4) The parameter values obtained at extreme points and inflection points are averaged and taken as final.

5) Procedures for p.p. 3 and 4 are repeated to sequentially obtain the longitude, and then the height of the location of the desired IRI.

Below is a table for evaluating statistics and their relative increase (in times), assuming for various numbers of measurement points by mobile posts.

The table shows that with the same number of measurement points (displacement points), the method provides an increase in statistics compared with the prototype by more than two orders of magnitude

In the proposed method:

1) any complex equations of the Iranian position lines with hidden singularity errors hidden in them are excluded, and the proposed multiplicative functions of the difference in the relations of finite quantities (distances and inverse signal levels) are smooth and do not create singular errors,

2) provides the determination of the coordinates of the location of the IRI not only on the surface of the Earth, but also in space,

3) the minimum number of measurement points is reduced from four to one, which indicates an increase in the speed of the method compared to the prototype.

All this indicates the novelty of the proposed method.

It should be noted that the method is the most universal, does not require complex calculations and can be easily implemented.

Information sources

1. Reference for radio monitoring. International Telecommunication Union. - Geneva: Radiocommunication Bureau. 2002 .-- 585 p.

2. 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.

3. Patent RU No. 2306579, publ. September 20, 2007

4. E. Korn and T. Korn. Math reference. For scientists and engineers / Ed. Aramanovich I.G. - M .: Science. 1968.- 720 s.

Claims (1)

A multiplicative difference-relative method of a stationary-mobile determination of the coordinates of the location of a source of radio emission, based on measuring the signal levels of a source of radio emission (IRI) at several points in space that are not lying on one straight line, by scanning radio receivers moving in space, characterized in that for measuring levels IRI signals are used by two stationary radio monitoring posts, and the mobile radio monitoring post, used as the base, is connected to the hospital arry posts with communication lines and move along Μ≥1 points, measure the levels of IRI signals at stationary radio monitoring and mobile posts, make up at the last

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 inverse ratios of the corresponding measured values of the source signal levels, dichotomously or by the method of steepest descent, change the value of each of the IRI location parameters at constant values of the other two and find the points of extrema

paired multiplicative functions and inflection points

multiplicative functions taken in three, fixing after N multiple

averaging each source location parameter found at these points as final.

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