RU2526536C1 - Amplitude-based radio direction-finder (versions) - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: first (two-channel) version of amplitude-based radio direction-finders comprises series-connected eight-element antenna system, antenna switch, two-channel radio receiver, two-channel analogue-to-digital converter, first and second computers, adder, maximum search unit, third computer, averaging unit, display unit, clock generator with corresponding connections. A second (eight-channel) version of the amplitude-based radio direction-finder comprises series connected eight-element antenna system, eight-channel radio receiver, eight-channel analogue-to-digital converter, first computer, adder, maximum search unit, second computer, averaging unit, display unit and clock generator with corresponding connections.

EFFECT: design of small-size amplitude-based radio direction-finders while considerably maintaining high accuracy characteristics thereof.

9 cl, 9 dwg, 1 tbl, 1 app

Description

The group of inventions relates to radio engineering and can be used to determine the spatial parameters of radio emissions.

Known amplitude direction finder (see Mezin VK Automatic direction finders. - M .: Sov. Radio, 1969, p. 184-185), containing a series-connected antenna system (AC), a receiving device and an indication unit. Depending on the frequency range, a frame antenna or AC with a narrow beam pattern (for example, log-periodic) is used as AC.

The disadvantage of the analogue is the low accuracy of measuring the spatial parameters of the signals of radio emission sources (see V. Vartanesyan, Sport radio direction finding. - M.: DOSAAF, 1980).

A known amplitude direction finder (see Pat. US 3939477, Fig. 11, 17 Feb. 1976), comprising an antenna system, four adders, a switch, a two-channel radio receiver, a control unit and a display unit. The device provides higher accuracy in determining the direction to the source of radio emission due to the use of a larger dimension of the antenna system. The disadvantage of the analogue is the relatively low accuracy of the results of the measurements.

The closest in essence to the claimed devices is the automatic sector direction finder "Wullenwefer" (see Vartanesyan VA, Goikhman E.Sh., Rogatkin MI Radio direction finding. - M .: Sov. Radio, 1966, p. 134 -135).

The prototype device contains a series-connected antenna system, an antenna switch, a two-channel radio receiver, a computer and an indication unit, a control unit, the first output of which is connected to the control input of the antenna switch, and the second output to the control input of the computer (see N. Havela , Istrakshin A.D., Muravyov Yu.K., Serkov V.P. / Edited by Yu.K. Muravyov, Antennas. Part 1. - L .: YOU, 1961, p. 494-500).

The working sector of the prototype is determined by two groups of vibrators AC, selected in the direction of the source of radio emission (IRI). When the "total" (in-phase) of their inclusion form a radiation pattern (MD) with one lobe. With a diverse (antiphase) inclusion of groups of vibrators form a two-leaf DN. The determination of the direction of arrival of the IRI signals is carried out respectively by their maximum or minimum level.

Other embodiments of the prototype are known for various frequency ranges (see Rohde & Schwarz & Co. KG http://www.rohde-schwarz.com). The prototype provides increased accuracy in measuring the spatial parameters of the signals. However, a positive effect is achieved due to a significant increase in overall dimensions and the complexity of the device. Phasing and switching of antenna elements (AE) is carried out by a phase switch containing two inhomogeneous delay lines. The delay time of signals from one vibrator to another varies according to a sinusoidal law. A decrease in the number of AEs and the distance between them entails a decrease in accuracy characteristics.

Another disadvantage of the prototype is only a partial use of information about the electromagnetic field of the estimated signal due to the involvement for this purpose of only part of spatially separated antenna elements (for example, twelve out of forty). The latter circumstance reduces the accuracy of measurements (see Torrieri D.J. Princieples of military communications system. Dedham, Massachusetts. Artech Hause, inc., 1981. - 298 p.).

The aim of the claimed technical solutions is to develop a small-sized amplitude direction finder while maintaining to a large extent its high accuracy characteristics due to a more complete consideration of information about the signal field at spatially separated points.

The goal in the first embodiment of the inventive device is achieved by the fact that in the known device containing a series-connected antenna system, an antenna switch and a two-channel radio receiving device, a first calculator, an indication unit, characterized in that a two-channel analog-to-digital converter, a clock generator are additionally introduced, series-connected second calculator, adder, maximum search unit, decoder, third computer and averaging unit, information group the outputs of which are connected to the group of information inputs of the display unit, the group of information outputs of the second computer is connected to the second group of information inputs of the decoder, and the group of information inputs is connected to the group of information outputs of the first computer, the group of information inputs of which is connected to the group of information outputs of the two-channel analog-to-digital converter, the first and second information inputs of which are connected respectively to the first and second information outputs of two-channel radio receiver, and the output of the clock generator is connected to the clock inputs of the antenna switch and two-channel analog-to-digital converter, synchronization inputs of the first, second and third computers, averaging unit, adder, maximum search unit and decoder.

In this case, the antenna system is made of eight antenna elements evenly spaced around the cylindrical reflector.

. В свою очередь второй вычислитель определяет отношение нормированных сигналов в четырех диаметрально отстоящих друг от друга антенных элементах: $$h_5^1;h_6^2;h_7^3иh_8^4,$$

а также в восьми парах элементов, номера которых отличаются на две единицы: $$h_3^1;h_7^1;h_4^2;h_8^2;h_5^3;h_6^4;h_7^5иh_8^6$$

в соответствии с выражением $$h_j^i=h_1^i/h_1^j,i,j=\mathrm{2,3,}\dots ,\mathrm{8,}i\ne j.$$

The first calculator determines the normalized signal levels at the outputs of the antenna elements U _i , i = 2, 3, ..., 8, relative to the signal level at the output of the first antenna element $$U_{\mathrm{one}}:h_{\mathrm{one}}^i=U_i/U_{\mathrm{one}}$$

. In turn, the second calculator determines the ratio of normalized signals in four antenna elements diametrically spaced from each other: $${\mathrm{<figure-callout\; id="5"\; label="h"\; filenames="00000111.png,00000113.png"\; state="\{\{state\}\}">h</figure-callout>}}_5^{\mathrm{one}};{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^2;h_7^3\mathrm{and}{\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^{\mathrm{four}},$$

as well as in eight pairs of elements whose numbers differ by two units: $${\mathrm{<figure-callout\; id="3"\; label="h"\; filenames="00000109.png,00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_3^{\mathrm{one}};h_7^{\mathrm{one}};h_{\mathrm{four}}^2;{\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^2;{\mathrm{<figure-callout\; id="5"\; label="h"\; filenames="00000111.png,00000113.png"\; state="\{\{state\}\}">h</figure-callout>}}_5^3;{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^{\mathrm{four}};h_7^5\mathrm{and}{\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^6$$

according to the expression $$h_j^i=h_{\mathrm{one}}^i/h_{\mathrm{one}}^j,i,j=\mathrm{2,3}...,\mathrm{8,}i\ne j.$$

The third computer determines the estimated values of the direction of arrival of the signal φ in accordance with the expressions:

, $$tg\varphi =\frac{\left(h_p^{p-2}-h_p^{p+2}\right)+\left(h_p^{p-\mathrm{one}}-h_p^{p+\mathrm{one}}\right)+\left(h_p^{p-3}-h_p^{p+3}\right)}{\left(\mathrm{one}-h_p^{p+\mathrm{four}}\right)+\left(h_p^{p+\mathrm{one}}-h_p^{p+3}\right)+\left(h_p^{p-\mathrm{one}}-h_p^{p-3}\right)}$$

,

, $$tg\left(\varphi -\frac{\pi }{\mathrm{four}}\right)=\frac{\left(h_p^{p-3}-h_p^{p+\mathrm{one}}\right)+\left(h_p^{p-2}-\mathrm{one}\right)+\left(h_p^{p+\mathrm{four}}-h_p^{p+2}\right)}{\left(h_p^{p-\mathrm{one}}-h_p^{p+3}\right)+\left(h_p^{p-2}-h_p^{p+\mathrm{four}}\right)+\left(\mathrm{one}-h_p^{p+2}\right)}$$

,

, $$tg\left(\varphi +\frac{\pi }{\mathrm{four}}\right)=\frac{\left(h_p^{p-\mathrm{one}}-h_p^{p+3}\right)+\left(\mathrm{one}-h_p^{p+2}\right)+\left(h_p^{p-2}-h_p^{p+\mathrm{four}}\right)}{\left(h_p^{p+\mathrm{one}}-h_p^{p-3}\right)+\left(h_p^{p+2}-h_p^{p+\mathrm{four}}\right)+\left(\mathrm{one}-h_p^{p-2}\right)}$$

,

where p is the number of the antenna element selected as the reference.

The goal in the second embodiment of the inventive device is achieved by the fact that in a known amplitude direction finder containing an antenna system, a radio receiver, a first calculator and an indication unit, characterized in that an additional clock, an eight-channel analog-to-digital converter, a series-connected adder, a block are introduced maximum search, decoder, second calculator and averaging unit, the group of information outputs of which is connected to the group of information inputs of the bl indications, and the group of information inputs of the adder is connected to the group of information outputs of the first calculator and the second group of information inputs of the decoder, the group of information inputs of the eight-channel analog-to-digital converter is connected to the group of information outputs of the radio receiver made by the eight-channel, and the group of information outputs to the group of information inputs the first computer, the output of the clock generator is connected to the clock input of the eight-channel analog-to-digital converter the developer, the synchronization inputs of the first and second calculators, the averaging unit, the adder, the maximum search unit and the decoder, and the information inputs of the radio receiver are connected to the outputs of the corresponding antenna elements of the antenna system.

In this case, the antenna system of the amplitude direction finder is made of eight antenna elements evenly spaced around the cylindrical reflector.

а также в четырнадцати парах элементов: $$h_3^1;h_7^1;h_4^2;h_8^2;h_5^3;h_6^4;h_7^5;h_6^8;h_1^8;h_1^2;h_7^8;h_6^5;h_7^6;иh_2^3$$

в соответствии с выражением $$h_j^i=U_i/U_j;$$

где U_i, U_j - уровни сигналов на выходах i-го и j-го антенных элементов соответственно, i,j=1,2,3,…, 8, i≠j.The first calculator of the amplitude direction finder determines the ratio of signal levels in four antenna elements diametrically spaced from each other: $${\mathrm{<figure-callout\; id="5"\; label="h"\; filenames="00000111.png,00000113.png"\; state="\{\{state\}\}">h</figure-callout>}}_5^{\mathrm{one}};{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^2;h_7^3\mathrm{and}{\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^{\mathrm{four}},$$

and also in fourteen pairs of elements: $${\mathrm{<figure-callout\; id="3"\; label="h"\; filenames="00000109.png,00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_3^{\mathrm{one}};h_7^{\mathrm{one}};h_{\mathrm{four}}^2;{\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^2;{\mathrm{<figure-callout\; id="5"\; label="h"\; filenames="00000111.png,00000113.png"\; state="\{\{state\}\}">h</figure-callout>}}_5^3;{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^{\mathrm{four}};h_7^5;{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^8;h_{\mathrm{one}}^8;h_{\mathrm{one}}^2;h_7^8;{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^5;h_7^6;\mathrm{and}{\mathrm{<figure-callout\; id="2"\; label="h"\; filenames="00000108.png,00000109.png"\; state="\{\{state\}\}">h</figure-callout>}}_2^3$$

according to the expression $$h_j^i=U_i/U_j;$$

where U _i , U _j are the signal levels at the outputs of the i-th and j-th antenna elements, respectively, i, j = 1,2,3, ..., 8, i ≠ j.

In turn, the second calculator determines the estimated values of the direction of arrival of the signal φ in accordance with the expressions:

, $$tg\varphi =h_p^{p-2}\frac{\left(\mathrm{one}-h_{p-2}^{p+2}\right)+h_{p-2}^{p-\mathrm{one}}\left(\mathrm{one}-h_{p-\mathrm{one}}^{p+\mathrm{one}}\right)+h_{p-2}^{p-3}\left(\mathrm{one}-h_{p-3}^{p+3}\right)}{\left(\mathrm{one}-h_p^{p+\mathrm{four}}\right)+h_p^{p+\mathrm{one}}\left(\mathrm{one}-h_{p+\mathrm{one}}^{p+3}\right)+h_p^{p-\mathrm{one}}\left(\mathrm{one}-h_{p-\mathrm{one}}^{p-3}\right)}$$

,

, $$tg\left(\varphi -\frac{\pi }{\mathrm{four}}\right)=h_{p-\mathrm{one}}^{p-3}\frac{\left(\mathrm{one}-h_{p-3}^{p+\mathrm{one}}\right)+h_{p-3}^{p-2}\left(\mathrm{one}-h_{p-2}^p\right)+h_{p-3}^{p+\mathrm{four}}\left(\mathrm{one}-h_{p+\mathrm{four}}^{p+2}\right)}{\left(\mathrm{one}-h_{p-\mathrm{one}}^{p+3}\right)+h_{p-\mathrm{one}}^{p-2}\left(\mathrm{one}-h_{p-2}^{p+\mathrm{four}}\right)+h_{p-\mathrm{one}}^p\left(\mathrm{one}-h_p^{p+2}\right)}$$

,

, $$tg\left(\varphi +\frac{\pi }{\mathrm{four}}\right)=h_{p+\mathrm{one}}^{p-\mathrm{one}}\frac{\left(\mathrm{one}-h_{p-\mathrm{one}}^{p+3}\right)+h_{p-\mathrm{one}}^p\left(\mathrm{one}-h_p^{p+2}\right)+h_{p-\mathrm{one}}^{p-2}\left(\mathrm{one}-h_{p-2}^{p+\mathrm{four}}\right)}{\left(\mathrm{one}-h_{p+\mathrm{one}}^{p-3}\right)+h_{p+\mathrm{one}}^{p+2}\left(\mathrm{one}-h_{p+2}^{p+\mathrm{four}}\right)+h_{p+\mathrm{one}}^p\left(\mathrm{one}-h_p^{p-2}\right)}$$

,

where p is the number of the antenna element selected as the reference.

The listed new set of essential features due to the fact that a number of elements difficult to implement are excluded, and the antenna system design is greatly simplified and, taking into account the newly introduced blocks and connections, allows to achieve the purpose of the invention: to develop two versions of a simplified small-sized amplitude direction finder while maintaining largely its accuracy characteristics.

The inventive device is illustrated by drawings, which show:

figure 1 is a generalized block diagram of a first embodiment of an amplitude direction finder;

figure 2 is a generalized structural diagram of a second embodiment of an amplitude direction finder;

figure 3 illustrates the appearance of the antenna system;

figure 4 shows the numbering order of the antenna elements of the antenna system after the assignment of the reference antenna element p;

figure 5 - algorithm of the first embodiment of the amplitude of the direction finder;

figure 6 - algorithm of the second embodiment of the implementation of the amplitude direction finder;

figure 7 - drawings explaining the operation of the device:

для первого варианта реализации амплитудного пеленгатора;a) selected signal ratios $$h_j^i$$

for the first embodiment of an amplitude direction finder;

;b) the procedure for forming the sum of the first three signal relations $${\psi }_{}^{}$$$${}_5^{\mathrm{one}}$$

;

on Fig illustrates the dependence of the standard deviation of the bearings from the true value at different signal-to-noise ratios;

figure 9 shows the dependence of the required number of measurements to ensure a given estimation accuracy with a probability of 0.9.

The invention consists in the following. The prototype device that implements the amplitude method for determining the direction of arrival of the radio signal, provides high measurement accuracy. However, it is characterized by large dimensions, high complexity of implementation, which entails, in addition, its significant cost, strict requirements for the location for its deployment, high requirements for the qualification of staff, etc. Simplification of the antenna system (the most complex element) by reducing the number of antenna elements leads to a decrease in the accuracy characteristics of the meter. In the proposed small-sized (in comparison with the prototype) amplitude direction finders, the simplification of the antenna system, together with the exception of the phase switch (in the first version, by replacing it with the usual one) is compensated by a set of more complete statistics on the electromagnetic field in the measurement zone. The processing involves the accepted (for the second option - simultaneously) radiation by all spatially separated antenna elements. The theoretical rationale for the technical solutions adopted is given in the Appendix.

The first variant of the implementation of the amplitude direction finder (see Figs. 1 and 5) comprises a series-connected antenna system 1, an antenna switch 2 and a two-channel radio receiver 3, a first calculator 5, and an indication unit 12.

To develop a simplified small-sized amplitude-direction finder while maintaining to a large extent its accuracy characteristics due to a more complete consideration of information about the signal field at spatially separated points, a two-channel analog-to-digital converter 4, a clock generator 13, serially connected to a second calculator 6, adder 7, and a search block are additionally introduced a maximum of 8, a decoder 9, a third calculator 10 and an averaging unit 11, the group of information outputs of which are connected to the group of information of the input inputs of the display unit 12, the group of information outputs of the second computer is connected to the second group of information inputs of the decoder 9, and the group of information inputs of the second computer 6 is connected to the group of information outputs of the first computer 5, the group of information inputs of which is connected to the group of information outputs of the two-channel analog-to-digital converter 4, the first and second information inputs of which are connected respectively to the first and second information outputs of a two-channel radio the receiver device 3, and the output of the clock generator 13 is connected to the clock inputs of the antenna switch 2 and the two-channel analog-to-digital converter 4, synchronization inputs of the first 5, second 6 and third 10 computers, averaging unit 11, adder 7, maxim search unit 8 and decoder 9 .

The work of a two-channel amplitude direction finder (first embodiment) is as follows (see figures 1, 5). Using blocks 1-3, the search and detection of IRI signals in a given frequency band ΔF are carried out. The signals received by the antenna system 1 at a frequency f _v are supplied to the corresponding inputs of the antenna switch 2. The task of the latter is to provide a serial connection of the output of one of the antenna elements i, i = 2, 3, ... 8, to the second information input of block 3. At the first ( reference) input is constantly connected to the output of the first antenna element. The task of the two-channel radio receiving device 3 is to amplify the signals, filter them and transfer (if necessary) to an intermediate frequency, for example 10.7 MHz. From the outputs of the receiving paths of block 3, the signals are fed to the corresponding inputs of the two-channel analog-to-digital converter 4, where their amplitudes U _i and U _{1 are} synchronously converted to digital form. The obtained values of U ₁ and U _i , i = 2,3, ..., 8, then go to the corresponding inputs of the first calculator 5.

i=2, 3, …, 8. Выполнение данной операции необходимо для приведения уровней сигналов, измеренных в различные моменты времени, к общим условиям.The functions of block 5 include finding normalized relative to the signal level at the output of the first AE values in accordance with the expression $$h_{\mathrm{one}}^i=U_i/U_{\mathrm{one}},$$

i = 2, 3, ..., 8. This operation is necessary to bring the signal levels measured at different points in time to general conditions.

поступают на группу информационных входов второго вычислителя 6. Здесь находится отношение сигналов в четырех парах диаметрально отстоящих друг от друга антенных элементах $$(h_5^1;h_6^2;h_7^3иh_8^4),$$

а также в восьми парах элементов, номера которых отличаются на две единицы $$(h_3^1;h_7^1;h_4^2;h_8^2;h_5^3;h_6^4;h_7^5иh_8^6).$$

Вычисление осуществляют по формулеThe values measured in block 5 $$h_{\mathrm{one}}^i$$

arrive at the group of information inputs of the second calculator 6. Here is the ratio of signals in four pairs of antenna elements diametrically spaced from each other $$({\mathrm{<figure-callout\; id="5"\; label="h"\; filenames="00000111.png,00000113.png"\; state="\{\{state\}\}">h</figure-callout>}}_5^{\mathrm{one}};{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^2;h_7^3\mathrm{and}{\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^{\mathrm{four}}),$$

as well as in eight pairs of elements whose numbers differ by two units $$({\mathrm{<figure-callout\; id="3"\; label="h"\; filenames="00000109.png,00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_3^{\mathrm{one}};h_7^{\mathrm{one}};h_{\mathrm{four}}^2;{\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^2;{\mathrm{<figure-callout\; id="5"\; label="h"\; filenames="00000111.png,00000113.png"\; state="\{\{state\}\}">h</figure-callout>}}_5^3;{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^{\mathrm{four}};h_7^5\mathrm{and}{\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^6).$$

The calculation is carried out according to the formula

$$h_j^i=h_{\mathrm{one}}^i/h_{\mathrm{one}}^j.$$

At the next stage, in the adder 7, based on the results obtained in block 6, the sums of the phases of the signal relations in four triples are determined. The latter are compiled as follows (see Fig.7, b). To the phase relationship of the signals of opposite antenna elements ("large base") are added the phase relationship of signals with a "small base" parallel to the "large" as follows:

$${\mathrm{<figure-callout\; id="5"\; label="\psi "\; filenames="00000111.png,00000113.png"\; state="\{\{state\}\}">\psi </figure-callout>}}_5^{\mathrm{one}}=\arg \left({\mathrm{<figure-callout\; id="5"\; label="h"\; filenames="00000111.png,00000113.png"\; state="\{\{state\}\}">h</figure-callout>}}_5^{\mathrm{one}}\right)+\arg \left(h_{\mathrm{four}}^2\right)+\arg \left({\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^8\right);$$

$${\mathrm{<figure-callout\; id="6"\; label="\psi "\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">\psi </figure-callout>}}_6^2=\arg \left({\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^2\right)+\arg \left({\mathrm{<figure-callout\; id="5"\; label="h"\; filenames="00000111.png,00000113.png"\; state="\{\{state\}\}">h</figure-callout>}}_5^3\right)+\arg \left(h_7^{\mathrm{one}}\right);$$

$${\psi }_7^3=\arg \left(h_7^3\right)+\arg \left({\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^{\mathrm{four}}\right)+\arg \left({\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^2\right);(\mathrm{one})$$

$${\mathrm{<figure-callout\; id="8"\; label="\psi "\; filenames="00000110.png"\; state="\{\{state\}\}">\psi </figure-callout>}}_8^{\mathrm{four}}=\arg \left({\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^{\mathrm{four}}\right)+\arg \left(h_{\mathrm{one}}^3\right)+\arg \left(h_7^5\right).$$

поступают на вход блока поиска максимума 8. В функции последнего входит нахождение тройки, у которой сумма фаз отношений сигналов максимальна. На основе полученных результатов определяется направление прихода электромагнитной волны с точностью до ±π/4. Для этого находится знак максимальной суммы отношений $${\psi }_j^i$$

. Если последний отрицательный, то ориентировочное направление распространения электромагнитной волны от i-го к j-му АЭ, в противном случае - от j-го к i-му АЭ.Values Found in Block 7 $${\psi }_j^i$$

arrive at the input of the maximum search block 8. The functions of the latter include finding a triple in which the sum of the phases of the signal relations is maximum. Based on the results obtained, the direction of arrival of the electromagnetic wave is determined with an accuracy of ± π / 4. To do this, find the maximum relationship sign $${\psi }_j^i$$

. If the latter is negative, then the approximate direction of propagation of the electromagnetic wave from the i-th to j-th AE, otherwise - from the j-th to i-th AE.

которые поступают с группы информационных выходов второго вычислителя 6. Порядок новых присвоений приведен в таблице.Next, in the decoder 9 renumbering of the antenna elements is performed depending on preliminary information about the direction of propagation of the electromagnetic wave, which is fed to the first group of information inputs. The second group of information inputs of block 9 contains current values $$h_j^i,$$

which come from the group of information outputs of the second calculator 6. The order of new assignments is shown in the table.

Assignment table No. of elements Ex. distribution one 2 3 four 5 6 7 8 1 → 5 p p + 1 p + 2 p + 3 p + 4 p-3 p-2 p-1 2 → 6 p-1 p p + 1 p + 2 p + 3 p + 4 p-3 R-2 3 → 7 p-2 p-1 p p + 1 p + 2 p + 3 p + 4 p-3 4 → 8 p-3 p-2 p-1 p p + 1 p + 2 P + 3 p + 4 5 → 1 p + 4 p-3 p-2 p-1 p p + 1 p + 2 p + 3 6 → 2 p + 3 p + 4 p-3 p-2 p-1 p p + 1 p + 2 7 → 3 p + 2 p + 3 p + 4 p-3 p-2 p-1 P p + 1 8 → 4 p + 1 p + 2 p + 3 p + 4 p-3 p-2 p-1 p

This operation is equivalent to the purpose of the reference antenna element φ, which is necessary for use in determining the estimated values of φ in the third computer 10. The latter in block 10 are in accordance with the expressions (19) ÷ (21) of the Appendix.

, которое в заданной форме отображается блоком 12. Синхронность выполнения названных операций блоками 2, 4-11 обеспечивается импульсами тактового генератора 13.The estimated value averaged in block 11 is taken as the true value of φ $$\overline{\varphi }$$

, which in a given form is displayed by block 12. Synchronization of the execution of these operations by blocks 2, 4-11 is provided by the pulses of the clock generator 13.

A second embodiment of an amplitude direction finder (see FIGS. 2 and 6) comprises an antenna system 14, a radio receiver 15, a first calculator 17, and an indication unit 23.

To create a simplified small-sized amplitude direction finder while maintaining to a large extent its accuracy characteristics due to a more complete consideration of information about the signal field at spatially separated points, a clock generator 24, an eight-channel analog-to-digital converter 16, a series-connected adder 18, a maximum search unit 19, and a decoder are additionally introduced 20, the second calculator 21 and the averaging unit 22, the group of information outputs of which are connected to the group of information inputs of the indie block 23, and the group of information inputs of the adder 18 is connected to the group of information outputs of the first calculator 17 and the second group of information inputs of the decoder 20, the group of information inputs of the eight-channel analog-to-digital converter 16 is connected to the group of information outputs of the radio receiver 15 made by eight-channel, and the group of information outputs - with a group of information inputs of the first calculator 17, the output of the clock generator 24 is connected to the clock input of an eight-channel analog-digital reobrazovatelya 16, a synchronization input 17 of the first and second calculators 21, the averaging unit 22, an adder 18, a maximum searcher 19 and decoder 20, and the data inputs of eight-receiving device 15 are connected to the outputs of the respective antenna elements of the antenna system.

The operation of the eight-channel amplitude direction finder (second embodiment) is as follows. Using blocks 14 and 15, signals are simultaneously received in a given frequency band ΔF. The signals received at the eight-element antenna system 14 at a frequency f _v are supplied to the corresponding inputs of the eight-channel radio receiving device 15.

In the eight-channel radio receiving device 15, the signals coming from the outputs of all AEs are simultaneously amplified, filtered and transferred (if necessary) to an intermediate frequency, for example, 10.7 MHz. From the outputs of the receiving paths of block 15, the signals are simultaneously sent to the corresponding inputs of the eight-channel analog-to-digital converter 16, where their amplitudes U _{i are} synchronously converted to digital form. The values obtained simultaneously U _i , i = 1,2, ..., 8, then go to the corresponding inputs of the first calculator 17.

а также в четырнадцати парах элементов $$(h_3^1;h_7^1;h_4^2;h_8^2;h_5^3;h_6^4;h_7^5;h_6^8;h_1^8;h_1^2;h_7^8;h_6^5;h_7^6;иh_2^3)$$

в соответствии с выражением $$h_1^i=U_i/U_1$$

, i, j - номера антенных элементов. В данном варианте исполнения амплитудного радиопеленгатора отпала необходимость в выполнении операции нормирования значений U_i-х уровней сигналов, i=2, 3,…, 8, к величине U₁ вследствие одновременного их приема.The functions of block 17 include finding the relations of signal levels in four antenna elements diametrically spaced from each other $$({\mathrm{<figure-callout\; id="5"\; label="h"\; filenames="00000111.png,00000113.png"\; state="\{\{state\}\}">h</figure-callout>}}_5^{\mathrm{one}};{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^2;h_7^3\mathrm{and}{\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^{\mathrm{four}}),$$

as well as fourteen pairs of elements $$({\mathrm{<figure-callout\; id="3"\; label="h"\; filenames="00000109.png,00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_3^{\mathrm{one}};h_7^{\mathrm{one}};h_{\mathrm{four}}^2;{\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^2;{\mathrm{<figure-callout\; id="5"\; label="h"\; filenames="00000111.png,00000113.png"\; state="\{\{state\}\}">h</figure-callout>}}_5^3;{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^{\mathrm{four}};h_7^5;{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^8;h_{\mathrm{one}}^8;h_{\mathrm{one}}^2;h_7^8;{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^5;h_7^6;\mathrm{and}{\mathrm{<figure-callout\; id="2"\; label="h"\; filenames="00000108.png,00000109.png"\; state="\{\{state\}\}">h</figure-callout>}}_2^3)$$

according to the expression $$h_{\mathrm{one}}^i=U_i/U_{\mathrm{one}}$$

, i, j are the numbers of antenna elements. In this embodiment, the amplitude of the direction finder eliminated the need for normalization of the values of U _i signal levels, i = 2, 3, ..., 8, to the value of U ₁ due to their simultaneous reception.

поступают на вход блока поиска максимума 19. По аналогии с блоком 8 в его функции входит нахождение тройки, у которой модуль суммы максимальный. На основе полученных результатов с учетом знака $$\max {\psi }_j^i$$

определяется направление прихода электромагнитной волны с точностью до ±π/4.The following three stages of operation of the device coincide with the operations performed by the amplitude direction finder according to the first embodiment. In the adder 18, on the basis of the results obtained by the block 17, the sums of the phases of the signal relations in four triples (1) are determined. Values Found in Block 18 $${\psi }_j^i$$

arrive at the input of the maximum search block 19. By analogy with block 8, its function includes finding the three for which the maximum modulus is. Based on the results, including the sign $$\max {\psi }_j^i$$

the direction of arrival of the electromagnetic wave is determined with an accuracy of ± π / 4.

In the decoder 20, the renumbering of the antenna elements is performed depending on the direction of propagation of the electromagnetic wave. The assignment order is given in the table (operation of assigning the support element p).

At the next stage, in the second calculator 21, the estimated values of the bearing of the signal φ are determined in accordance with the expressions

$$tg\varphi =h_p^{p-2}\frac{\left(\mathrm{one}-h_{p-2}^{p+2}\right)+h_{p-2}^{p-\mathrm{one}}\left(\mathrm{one}-h_{p-\mathrm{one}}^{p+\mathrm{one}}\right)+h_{p-2}^{p-3}\left(\mathrm{one}-h_{p-3}^{p+3}\right)}{\left(\mathrm{one}-h_p^{p+\mathrm{four}}\right)+h_p^{p+\mathrm{one}}\left(\mathrm{one}-h_{p+\mathrm{one}}^{p+3}\right)+h_p^{p-\mathrm{one}}\left(\mathrm{one}-h_{p-\mathrm{one}}^{p-3}\right)};(2)$$

$$tg\left(\varphi -\frac{\pi }{\mathrm{four}}\right)=h_{p-\mathrm{one}}^{p-3}\frac{\left(\mathrm{one}-h_{p-3}^{p+\mathrm{one}}\right)+h_{p-3}^{p-2}\left(\mathrm{one}-h_{p-2}^p\right)+h_{p-3}^{p+\mathrm{four}}\left(\mathrm{one}-h_{p+\mathrm{four}}^{p+2}\right)}{\left(\mathrm{one}-h_{p-\mathrm{one}}^{p+3}\right)+h_{p-\mathrm{one}}^{p-2}\left(\mathrm{one}-h_{p-2}^{p+\mathrm{four}}\right)+h_{p-\mathrm{one}}^p\left(\mathrm{one}-h_p^{p+2}\right)};(3)$$

$$tg\left(\varphi +\frac{\pi }{\mathrm{four}}\right)=h_{p+\mathrm{one}}^{p-\mathrm{one}}\frac{\left(\mathrm{one}-h_{p-\mathrm{one}}^{p+3}\right)+h_{p-\mathrm{one}}^p\left(\mathrm{one}-h_p^{p+2}\right)+h_{p-\mathrm{one}}^{p-2}\left(\mathrm{one}-h_{p-2}^{p+\mathrm{four}}\right)}{\left(\mathrm{one}-h_{p+\mathrm{one}}^{p-3}\right)+h_{p+\mathrm{one}}^{p+2}\left(\mathrm{one}-h_{p+2}^{p+\mathrm{four}}\right)+h_{p+\mathrm{one}}^p\left(\mathrm{one}-h_p^{p-2}\right)}.(\mathrm{four})$$

отображаются в заданной форме в блоке 23. Синхронность работы блоков 16-21 обеспечивается импульсами тактового генератора 24.As a result, the estimated values of φ are generated at the output of block 21, which are averaged in block 22. The results obtained in block 22 $$\overline{\varphi }$$

are displayed in a predetermined form in block 23. The synchronism of operation of blocks 16-21 is provided by the pulses of the clock generator 24.

(в обеих вариантах реализации) используется информация о комплексных амплитудах сигналов на выходах всех восьми пространственно разнесенных АЭ. При этом количество выполняемых вычислений ограничено (используются не все возможные сочетания антенных элементов i; j=1, 2, …, 8, i≠j, а лишь их наиболее информативная часть) благодаря особенности применяемой геометрии АС 1 (14).As a result of performing the above operations when determining the values $$\overline{\varphi }$$

(in both implementations), information is used on the complex amplitudes of the signals at the outputs of all eight spatially separated AEs. Moreover, the number of calculations performed is limited (not all possible combinations of antenna elements i; j = 1, 2, ..., 8, i ≠ j are used, but only their most informative part) due to the peculiarities of the applied geometry of AC 1 (14).

. При этом значительного увеличения временных затрат на обработку (по сравнению с двухканальным вариантом реализации) не наблюдается в силу исключения первого этапа вычислений. Увеличение канальности обработки предполагает некоторое усложнение пеленгатора и, как следствие, - незначительное увеличение его себестоимости.The second embodiment of the implementation of the amplitude direction finder has higher accuracy characteristics (compared with the first option) due to the fact that the measurement of the complex amplitudes of the signals U _i in all AEs is performed simultaneously. In addition, it is characterized by a higher noise immunity due to the greater number of calculations used in processing (additionally determined $$(h_p^{p-\mathrm{one}};h_p^{p+\mathrm{one}};h_{p-2}^{p-\mathrm{one}};h_{p-3}^{p+\mathrm{four}};h_{p-2}^{p-3};h_{p+\mathrm{one}}^{p+2})$$

. At the same time, a significant increase in processing time (in comparison with the two-channel implementation option) is not observed due to the exclusion of the first stage of calculations. An increase in the processing channel implies some complication of the direction finder and, as a result, a slight increase in its cost.

The proposed devices use well-known elements and blocks described in the scientific and technical literature. The embodiment of the antenna elements and antenna arrays 1 and 14 (see figure 3) is known and widely covered in the literature (see Markov G.T., Chaplin A.F. Excitation of electromagnetic waves. - M .: Radio and communication, 1983 , 296 p.). The type of AE used is determined by the range of operating frequencies. As the latter, pairs of antiphase dipoles can be used.

The implementation of two-channel 3 and eight-channel 15 radio receivers is known. The latter are serially produced by Special Technological Center LLC, St. Petersburg (see Special Technological Center. Information and Analytical Almanac. / Ed. By A.A. Getmantsev. - St. Petersburg, 2011).

In addition, these units can be implemented with an appropriate set of ICOM type IC-R8500 receivers (see Communication Receiver IC-R8500. Instruction Manual). In this case, the first and second local oscillators of one of the receivers are used simultaneously as the first and second local oscillators, respectively, of the remaining receivers.

The implementation of antenna switch 2 is known and does not cause difficulties (see Veniaminov V.N. et al. Microcircuits and their application. M .: Radio and communications, 1989. - 240 p .; Vaysblat A.V. Microwave switching devices on semiconductor diodes . - M.: Radio and Communications, 1987. - 120 p.).

The implementation of two-channel 4 and eight-channel 16 analog-to-digital converters is known and widely covered in the literature. Special Technological Center LLC, St. Petersburg, is mass-produced (see http://stc-spb.ru).

Последний представляет собой последовательно подключенные делитель и буферную память. С выходов блока 4 последовательно поступают значения U_i в совокупности с соответствующим им в данный момент времени t_n значением U₁. Полученные в результате деления значения $$h_1^i$$

запоминаются в буферной памяти блока 5. После нахождения всех значений $$h_1^i$$

, i=2, 3,…, 8 очередным импульсом тактового генератора 13 последние одновременно поступают на соответствующие входы второго вычислителя 6, а содержимое буферной памяти обнуляется. Блок 5 готов к выполнению очередного цикла работы. Реализация элементов блока 5 трудностей не вызывает, может быть выполнен на микросхемах элементарной логики ТТЛ-уровней.The function of the first calculator 5 includes finding normalized relative to the signal level at the output of the first AE signal values AP in accordance with the expression $$h_j^i=U_i/U_j,i=23...,8.$$

The latter is a series-connected divider and buffer memory. From the outputs of block 4, the values U _i in sequence are received in conjunction with the corresponding value of U ₁ corresponding to them at a given moment in time t _n . Dividing Values $$h_{\mathrm{one}}^i$$

stored in the buffer memory of block 5. After finding all the values $$h_{\mathrm{one}}^i$$

, i = 2, 3, ..., 8 with the next pulse of the clock generator 13, the latter simultaneously arrive at the corresponding inputs of the second calculator 6, and the contents of the buffer memory are reset. Block 5 is ready for the next cycle of work. The implementation of the elements of block 5 does not cause difficulties; it can be performed on chips of elementary logic of TTL levels.

), а также в восьми парах элементов, номера которых отличаются на две единицы $$(h_3^1;h_7^1;h_4^2;h_8^2;h_5^3;h_6^4;h_7^5иh_8^6).$$

Вычисление осуществляется в соответствии с выражением $$h_j^i=h_1^i/h_1^j.$$

Эта функция реализуется с помощью двенадцати параллельно подключенных делителей, входы делимого и делителя которых соответствующим образом соединены (скоммутированы) с группами информационных выходов буферного регистра блока 5.In block 6, the signal ratio is determined (see Fig. 7, a) in four pairs of antenna elements diametrically spaced from each other ( $${\mathrm{<figure-callout\; id="5"\; label="h"\; filenames="00000111.png,00000113.png"\; state="\{\{state\}\}">h</figure-callout>}}_5^{\mathrm{one}};{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^2;h_7^3\mathrm{and}{\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^{\mathrm{four}}$$

), as well as in eight pairs of elements whose numbers differ by two units $$({\mathrm{<figure-callout\; id="3"\; label="h"\; filenames="00000109.png,00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_3^{\mathrm{one}};h_7^{\mathrm{one}};h_{\mathrm{four}}^2;{\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^2;{\mathrm{<figure-callout\; id="5"\; label="h"\; filenames="00000111.png,00000113.png"\; state="\{\{state\}\}">h</figure-callout>}}_5^3;{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^{\mathrm{four}};h_7^5\mathrm{and}{\mathrm{<figure-callout\; id="8"\; label="h"\; filenames="00000110.png"\; state="\{\{state\}\}">h</figure-callout>}}_8^6).$$

The calculation is carried out in accordance with the expression $$h_j^i=h_{\mathrm{one}}^i/h_{\mathrm{one}}^j.$$

This function is implemented using twelve parallel-connected dividers, the inputs of the dividend and divider of which are appropriately connected (connected) with the groups of information outputs of the buffer register of block 5.

в АЭ в соответствии с $$h_j^i=U_i/U_j$$

. Отличие от блока 6 состоит в количестве используемых делителей. В блоке 17 дополнительно используется шесть параллельно подключенных делителей для нахождения значений $$h_1^8;h_1^2;h_7^8;h_6^5;h_7^6;иh_2^3$$

. Реализация блоков 6 и 11 трудностей не вызывает (см. Б.В.Тарабин и др./Под ред. Б.В.Тарабина. - 2-е изд., перераб. и доп. Справочник по интегральным микросхемам. - М.: Энергия, 1980. - 816 с.).Block 17 performs a similar (with block 6) function for finding signal ratios $$h_j^i$$

in AE in accordance with $$h_j^i=U_i/U_j$$

. The difference from block 6 is the number of dividers used. In block 17, six parallel dividers are additionally used to find values $$h_{\mathrm{one}}^8;h_{\mathrm{one}}^2;h_7^8;{\mathrm{<figure-callout\; id="6"\; label="h"\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">h</figure-callout>}}_6^5;h_7^6;\mathrm{and}{\mathrm{<figure-callout\; id="2"\; label="h"\; filenames="00000108.png,00000109.png"\; state="\{\{state\}\}">h</figure-callout>}}_2^3$$

. The implementation of blocks 6 and 11 does not cause difficulties (see B.V. Tarabin et al. / Edited by B.V. Tarabin. - 2nd ed., Revised and additional. Handbook of integrated circuits. - M .: Energy, 1980 .-- 816 p.).

(в соответствии с выражением 1). Каждый из них представляет из себя четыре параллельно подключенных сумматора, реализация которых трудностей не вызывает. Блоки поиска максимума 8 (19) предназначены для нахождения тройки выражения (1) Описания, у которой модуль суммы $${\psi }_j^i$$

максимальный. Далее с помощью названных блоков определяется направления прихода электромагнитной волны с точностью до π/4 путем определения знака максимальной суммы $${\psi }_j^i$$

. Блок поиска максимума может быть выполнен по пирамидальной схеме с использованием быстродействующих компараторов (см. Ред. Э. Справочное пособие по высокочастотной схемотехнике: Схемы, блоки, 50-омная техника: Пер. с нем. - М.: Мир, 1990. - 256 с.). Совокупность блоков 5, 6, 7 и 8 (для первого варианта реализации), а также 17, 18 и 19 (второй вариант реализации) могут быть выполнены в виде автомата на базе высокопроизводительного 16-разрядного микропроцессора К1810 ВМ86 (см. Вениаминов В.Н. и др. Микросхемы и их применение: Справочное пособие. - 3-е изд., перераб. и доп. - М.: Радио и связь, 1988. - 240 с.).Adders 7 (18) are designed to find the sums of the phases of the signal relations in four triples $${\psi }_5^{\mathrm{one}},{\mathrm{<figure-callout\; id="6"\; label="\psi "\; filenames="00000109.png,00000111.png"\; state="\{\{state\}\}">\psi </figure-callout>}}_6^2,{\psi }_7^3\mathrm{and}{\mathrm{<figure-callout\; id="8"\; label="\psi "\; filenames="00000110.png"\; state="\{\{state\}\}">\psi </figure-callout>}}_8^{\mathrm{four}}$$

(in accordance with expression 1). Each of them is four parallel connected adders, the implementation of which does not cause difficulties. The maximum search blocks 8 (19) are designed to find the triples of expression (1) of the Description, in which the modulus of the sum $${\psi }_j^i$$

maximum. Further, using the above blocks, the direction of arrival of the electromagnetic wave is determined with an accuracy of π / 4 by determining the sign of the maximum sum $${\psi }_j^i$$

. The maximum search block can be performed according to the pyramidal scheme using high-speed comparators (see. Ed. Reference manual on high-frequency circuitry: Circuits, blocks, 50 ohm technology: Translated from German.- M .: Mir, 1990. - 256 from.). The combination of blocks 5, 6, 7 and 8 (for the first implementation option), as well as 17, 18 and 19 (the second implementation option) can be made in the form of an automaton based on the high-performance 16-bit microprocessor K1810 VM86 (see Veniaminov V.N. . and other Microcircuits and their application: Reference manual. - 3rd ed., revised and additional - M: Radio and communications, 1988. - 240 p.).

. На основе управляющей информации на первых группах входов в дешифраторах 9 и 20 осуществляется переприсвоение адресных данных i и j в измеренных отношениях уровней сигналов $$h_j^i$$

на новые, например $$h_{j+2}^{i+2}$$

. Реализация блоков трудностей не вызывает. Могут быть реализованы с помощью постоянных запоминающих устройств (см. Лебедев О.Н. Микросхемы памяти и их применение. - М.: Радио и связь, 1990. - 160 с.; Большие интегральные схемы запоминающих устройств: Справочник/ А.Ю.Горденов и др. - М.: Радио и связь, 1990. - 288 с.).Decoders 9 and 20 are designed for renumbering of antenna elements depending on the direction of propagation of the electromagnetic wave, in accordance with the table above. The first group of their information inputs receives data on the direction of arrival of the radio wave with an accuracy of ± π / 4 from the outputs of blocks 8 and 19, respectively. The second groups of information inputs contain the corresponding values defined in blocks 6 and 17 $$h_j^i$$

. Based on the control information on the first groups of inputs in the decoders 9 and 20, address data i and j are reassigned in the measured signal level ratios $$h_j^i$$

to new ones, for example $$h_{j+2}^{i+2}$$

. The implementation of blocks of difficulties does not cause. They can be implemented using read-only memory devices (see O. Lebedev. Memory microcircuits and their application. - M.: Radio and communications, 1990. - 160 p .; Large integrated circuits of memory devices: Reference book / A.Yu. Gordenov et al. - M.: Radio and Communications, 1990. - 288 p.).

The third computer 10 is designed to find the estimated values of the direction of arrival of the radio signal φ in accordance with the expressions (19) ÷ (21) of the Appendix. The implementation of the block does not cause difficulties; it can be implemented on programmable read-only memory devices, for example, the K541 or K500 series. The second calculator 21 performs a function similar to block 10 — finding estimated values of the direction of arrival of the radio signal φ. This operation is performed in accordance with the expressions (2) - (4) Descriptions. Block 21 can also be implemented on chips of the K541 and K500 series.

направления прихода радиосигнала путем усреднения полученных ранее оценочных значений φ. Представляют из себя последовательно соединенные сумматор и делитель на три. Реализация блоков 11 и 22 известна и трудностей не вызывает (см. Б.В.Тарабин и др.; Под ред. Б.В.Тарабина. - 2-е изд., перераб. и доп. Справочник по интегральным микросхемам. - М.: Энергия, 1980. - 816 с.).Averaging blocks 11 and 22 are designed to find the true value $$\overline{\varphi }$$

directions of arrival of the radio signal by averaging the previously obtained estimated values of φ. They are a series-connected adder and a divider by three. The implementation of blocks 11 and 22 is known and does not cause difficulties (see B.V. Tarabin et al .; Edited by B.V. Tarabin. - 2nd ed., Revised and additional Handbook of integrated circuits. - M .: Energy, 1980 .-- 816 p.).

The construction of clock generators 13 and 24 is known and widely covered in the literature (see Radio receivers: a training manual for radio engineering. Special Universities / Yu.T. Davydov et al. - Moscow: Vysshaya Shkola, 1989. - 342 p.).

The implementation of indication blocks 13 and 23 is known and does not cause difficulties (see Bystrov A.Yu. et al. One hundred schemes with indicators. - M.: Radio and communications, 1990. - 112 p .; Password N.V., Kaydalov S .A. Sign-synthesizing indicators and their application: Handbook. - M.: Radio and communications, 1998. - 128 p.).

The production of blocks 4 through 11 in the first embodiment and blocks 16 through 22 in the second embodiment of the amplitude direction finder, respectively, is impractical due to insufficient speed, significant overall dimensions, weight and energy consumption. In this regard, it is advisable to execute the above blocks for each implementation on one signal processor TMS320c64l6 (see TMS320c6416: http: //focus/ti/com/docs/prod/folclers/print/TMS320c64'16.html) shown in FIGS. 5 and 6, respectively.

Based on the expressions (19) - (21) of the Appendix and (2) - (4) of the Description, an analysis of the characteristics of the proposed technical solutions has been performed (see Figs. 8 and 9). The antenna system (see Fig. 3) with a diameter of 0.3 meters was subject to consideration. On Fig shows the results of the calculation of the standard deviation of the bearings σ _φ from the true value in the frequency range from 20 to 1000 MHz for various signal-to-noise ratios at the input of the meter. For the aforementioned conditions (noise is “white”), the mathematical deviation of the value of φ coincides with the true one, which allows us to ensure a given measurement accuracy by averaging the accumulated results. Figure 9 shows the dependence of the required number of averagings γ to ensure accuracy of 1 °, 5 ° and 10 ° with a probability of 0.9. It can be seen that with a passband of 10 kHz (time of one measurement 0.5 · 10 ^-3 s), even with a standard deviation of σ _φ = 50 °, direction finding accuracy of 1 ° can be achieved in 3.5 s.

Thus, the proposed technical solutions implement precision characteristics commensurate with the prototype device. However, it is known that the prototype AS has a diameter of 105 meters and 40 AE. In the proposed device variants, the diameter of the speaker is 1 meter or less, contains 8 AE, which determines the positive effect. However, it should be noted that a significant increase in the overall dimensions of the speakers entails a loss of operability of the claimed devices due to the significant influence of the phase parameters of the received signals on the measurement results.

application

Calculation of spatial parameters of radio signals by a narrow-base amplitude direction finder

It is known that as elements of AS in amplitude direction finders, AEs with a certain orientation should be used (see Kukes I.S., Starik M.E. Fundamentals of radio direction finding. - M .: Sov. Radio, 1964). Most often, the latter are small frames or pairs of antiphase dipoles. Both have a cosine beam pattern in the azimuthal plane. Recently, however, direction finders are increasingly appearing whose antenna systems are a combination of dipoles located above a cylindrical screen as shown in FIG. 3.

The directional characteristic of a longitudinal dipole above a cylindrical surface is described by the following expression (see Markov G.T., Chaplin A.F. Excitation of electromagnetic waves. - M .: Radio and communication, 1983. - 296 p.)

$$E_z={\displaystyle \sum _{n=0}^{\infty }{A}_n\cos n\varphi ,}$$

moreover, with sufficient accuracy for practice, we can restrict ourselves to the first two members of the series.

In this case, the dependence of the signal level at the output terminals of the dipole on the direction of arrival of a plane electromagnetic wave is determined by the expression:

U = K · (A ₀ + A ₁ cosφ), (1)

where K = e ^ikbcosφ is the phase factor, here k = 2π / λ is the wave number, b is the radial distance from the dipole axis to the cylinder axis.

Consider the direction finding algorithm using eight antenna elements with the specified type of directivity. The named number of AEs evenly spaced around the circle through the angle π / 4 allows us to significantly simplify the algorithm of the device due to the use of periodic properties of sin-cos functions.

Let the direction of arrival of the electromagnetic wave with the direction of the axis of the antenna system at the p-th antenna element angle φ (see figure 4). The order of appointment of the p-th AE is discussed below.

Then the voltage at the outputs of the antenna elements p, p ± 1 and p ± 2 has the form:

U _p = K · (A ₀ + A ₁ cosφ); (2)

$$U_{p\pm \mathrm{one}}=K_{p\pm \mathrm{one}}\left[A_0+A_{\mathrm{one}}\cos \left(\varphi \pm \frac{\pi }{\mathrm{four}}\right)\right]=K_{p\pm \mathrm{one}}\left[A_0+\frac{A_{\mathrm{one}}}{\sqrt{2}}\left(\cos \varphi \mp \sin \varphi \right)\right];(3)$$

$$U_{p\pm 2}=K_{p\pm 2}\left[A_0+A_{\mathrm{one}}\cos \left(\varphi \pm \frac{\pi }{2}\right)\right]=K_{p\pm 2}\left[A_0\mp A_{\mathrm{one}}\sin \varphi \right];(\mathrm{four})$$

$$U_{p\pm 3}=K_{p\pm 3}\left[A_0+A_{\mathrm{one}}\cos \left(\varphi \pm \frac{3\pi }{\mathrm{four}}\right)\right]=K_{p\pm 3}\left[A_0-\frac{A\mathrm{one}}{\sqrt{2}}\left(\cos \varphi \pm \sin \varphi \right)\right];(5)$$

$$U_{p\pm \mathrm{four}}=K_{p\pm \mathrm{four}}\left[A_0+A_{\mathrm{one}}\cos \left(\varphi \pm \pi \right)\right]=K_{p\pm \mathrm{four}}\left[A_0-A_{\mathrm{one}}\cos \varphi \right].(6)$$

At low frequencies, i.e. when kb □ 1 is satisfied, the phase factors in expressions (2) ÷ (6) can be represented as:

K _p = e ^ikbcosφ = cos (kbcosφ) + isin (kbcosφ) ≈1 + ikbcosφ;

$$K_{p\pm \mathrm{one}}\approx \mathrm{one}+i\frac{kb}{\sqrt{2}}\left(\cos \varphi \mp \sin \varphi \right);$$

K _{p ± 2} ≈1 + ikbsinφ;

$$K_{p\pm 3}\approx \mathrm{one}-i\frac{kb}{\sqrt{2}}\left(\cos \varphi \pm \sin \varphi \right);$$

K _{p ± 4} ≈1-ikbcosφ.

Substituting these expressions in (2) ÷ (6), we find the signals normalized to the isotropic component of the directivity

$$\frac{{\mathrm{<figure-callout\; id="0"\; label="U\; p\; A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">U\; </figure-callout>}}_p}{A_{}}=\left(\mathrm{one}+ikb\cos \varphi \right)\left(\mathrm{one}+\frac{A_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}\cos \varphi \right);(7)$$

$$\frac{U_{p\pm \mathrm{one}}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}=\left[\mathrm{one}+\frac{ikb}{\sqrt{2}}\left(\cos \varphi \mp \sin \varphi \right)\right]\left[\mathrm{one}+\frac{\mathrm{one}}{\sqrt{2}}\frac{A_{\mathrm{one}}}{A_0}\left(\cos \varphi \mp \sin \varphi \right)\right];(8)$$

$$\frac{U_{p\pm 2}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}=\left[\mathrm{one}+ikb\sin \varphi \right]\left[\mathrm{one}\mp \frac{A_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}\sin \varphi \right];(9)$$

$$\frac{U_{p\pm 3}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}=\left[\mathrm{one}+\frac{ikb}{\sqrt{2}}\left(\cos \varphi \pm \sin \varphi \right)\right]\left[\mathrm{one}-\frac{\mathrm{one}}{\sqrt{2}}\frac{A_{\mathrm{one}}}{A_0}\left(\cos \varphi \pm \sin \varphi \right)\right];(10)$$

$$\frac{U_{p+\mathrm{four}}}{A_0}=\left(\mathrm{one}-ikb\cos \varphi \right)\left(\mathrm{one}-\frac{A_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}\cos \varphi \right).(\mathrm{eleven})$$

и $$\frac{U_{p+4}}{A_0}$$

дает следующий результат:Finding the difference of normalized signals $$\frac{U_{\mathrm{<figure-callout\; id="0"\; label="p\; U\; A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">p\; </figure-callout>}}}{U_A}$$

and $$\frac{U_{p+\mathrm{four}}}{A_0}$$

gives the following result:

$$\frac{U_p-U_{p+\mathrm{four}}}{A_0}=2\cos \varphi \left(\frac{A_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}+ikb\right).(12)$$

We calculate the differences of the normalized signals in parallel pairs of elements:

$$\frac{U_p{}_{+\mathrm{one}}-U_{p+3}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}=\sqrt{2}\cos \varphi \left(\frac{A_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}+ikb-\sqrt{2}ikb\frac{A_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}\sin \varphi \right).$$

Since kb □ 1, the third term in parentheses will be much smaller than the first, therefore:

$$\frac{U_{p+\mathrm{one}}-U_{p+3}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}\approx 2\cos \varphi \left(\frac{A_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}+ikb\right).(13)$$

Similarly, it can be shown that:

$$\frac{U_{p-\mathrm{one}}-U_{p-3}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}\approx \sqrt{2}\cos \varphi \left(\frac{A_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}+ikb\right).(\mathrm{fourteen})$$

In orthogonal pairs of elements, the differences of the normalized signals are determined from the expressions:

$$\frac{U_{p-2}-U_{p+2}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}=2\sin \varphi \left(\frac{A_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}+ikb\right);(\mathrm{fifteen})$$

$$\frac{U_{p-\mathrm{one}}-U_{p+\mathrm{one}}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}\approx \sqrt{2}\sin \varphi \left(\frac{A_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}+ikb\right);(16)$$

$$\frac{U_{p-3}-U_{p+3}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}=\sqrt{2}\sin \varphi \left(\frac{A_{\mathrm{one}}}{{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="00000112.png,00000113.png"\; state="\{\{state\}\}">A</figure-callout>}}_0}+ikb\right).(17)$$

It can be seen that the angle of wave arrival can be calculated by dividing any signal difference (12) ÷ (14) by any difference (15) ÷ (17). The maximum sensitivity of the inventive direction finders is achieved by summing the differences in signal levels (with small dimensions of the speakers, the latter have insignificant values):

$$tg\varphi =\frac{\left(U_{p-2}-U_{p+2}\right)+\left(U_{p-\mathrm{one}}-U_{p+\mathrm{one}}\right)+\left(U_{p-3}-U_{p+3}\right)}{\left(U_p-U_{p+\mathrm{four}}\right)+\left(U{p}_{+\mathrm{one}}-U_{p+3}\right)+\left(U_{p-\mathrm{one}}-U_{p-3}\right)}.(\mathrm{eighteen})$$

Since it is more convenient to measure not the absolute levels of signals, but their relationships, expression (18) should be converted to:

$$tg\varphi =\frac{\left(h_p^{p-2}-h_p^{p+2}\right)+\left(h_p^{p-\mathrm{one}}-h_p^{p+\mathrm{one}}\right)+\left(h_p^{p-3}-h_p^{p+3}\right)}{\left(\mathrm{one}-h_p^{p+\mathrm{four}}\right)+\left(h_p^{p+\mathrm{one}}-h_p^{p+3}\right)+\left(h_p^{p-\mathrm{one}}-h_p^{p-3}\right)},(19)$$

- отношение комплексных амплитуд сигналов на i-м и j-м диполях.Where $$h_j^i=\frac{U_i}{U_j}$$

- the ratio of the complex amplitudes of the signals on the i-th and j-th dipoles.

можно вычислить, сгруппировав антенные элементы в пары, ориентированные под углом π/4, по отношению к парам, рассмотренным выше.Value $$tg\left(\varphi -\frac{\pi }{\mathrm{four}}\right)$$

can be calculated by grouping the antenna elements into pairs oriented at an angle π / 4 with respect to the pairs discussed above.

We get:

$$tg\left(\varphi -\frac{\pi }{\mathrm{four}}\right)=\frac{\left(h_p^{p-3}-h_p^{p+\mathrm{one}}\right)+\left(h_p^{p-2}-\mathrm{one}\right)+\left(h_p^{p+\mathrm{four}}-h_p^{p+2}\right)}{\left(h_p^{p-\mathrm{one}}-h_p^{p+3}\right)+\left(h_p^{p-2}-h_p^{p+\mathrm{four}}\right)+\left(\mathrm{one}-h_p^{p+2}\right)}(\mathrm{twenty})$$

or

$$tg\left(\varphi +\frac{\pi }{\mathrm{four}}\right)=\frac{\left(h_p^{p-\mathrm{one}}-h_p^{p+3}\right)+\left(\mathrm{one}-h_p^{p+2}\right)+\left(h_p^{p-2}-h_p^{p+\mathrm{four}}\right)}{\left(h_p^{p+\mathrm{one}}-h_p^{p-3}\right)+\left(h_p^{p+2}-h_p^{p+\mathrm{four}}\right)+\left(\mathrm{one}-h_p^{p-2}\right)}.(21)$$

It is obvious that if the angle between the direction from the ith element to the jth and the direction of arrival of the electromagnetic wave lies within

$$-\frac{\pi }{\mathrm{four}}\le \varphi \le \frac{\pi }{\mathrm{four}},$$

будет больше нуля. Это значит, что фаза знаменателя выражения (19) должна быть меньше нуля.then the relationship phase $$h_j^i$$

will be greater than zero. This means that the phase of the denominator of expression (19) must be less than zero.

After calculations by formulas (19) - (21), the angle φ is averaged. There are no ambiguities arising during direction-finding by the Watson-Watt method in these devices, since the above condition is always fulfilled.

Claims (9)

1. An amplitude direction finder comprising a series-connected antenna system, an antenna switch and a two-channel radio receiving device, a first computer, an indication unit, characterized in that a two-channel analog-to-digital converter, a clock generator, a second computer, an adder, a maximum search unit are connected in series, a decoder, a third calculator and an averaging unit, the group of information outputs of which are connected to a group of information inputs of the display unit, a group the information outputs of the second computer is connected to the second group of information inputs of the decoder, and the group of information inputs is connected to the group of information outputs of the first computer, the group of information inputs of which is connected to the group of information outputs of a two-channel analog-to-digital converter, the first and second information inputs of which are connected respectively to the first and the second information outputs of the two-channel radio receiving device, and the output of the clock generator is connected to the clock input rows of the antenna switch and two-channel analog-to-digital converter clock inputs of the first, second and third calculators, averaging unit, adder, peak search unit and the decoder. 2. The amplitude direction finder according to claim 1, characterized in that the antenna system is made of eight antenna elements uniformly spaced around a cylindrical reflector. 3. The amplitude direction finder according to claim 2, characterized in that the first calculator determines the normalized signal levels at the outputs of the antenna elements U _i , i = 2, 3, ..., 8, relative to the signal level at the output of the first antenna element $$U_i:h_{\mathrm{one}}^i=U_i/U_{\mathrm{one}}$$

. 4. The amplitude direction finder according to claim 2, characterized in that the second calculator determines the ratio of normalized signals in four antenna elements diametrically spaced from each other: $$h_5^{\mathrm{one}}$$

; $$h_6^2$$

; $$h_7^3$$

and $$h_8^{\mathrm{four}}$$

, as well as in eight pairs of elements whose numbers differ by two units: $$h_3^{\mathrm{one}}$$

; $$h_7^{\mathrm{one}}$$

; $$h_{\mathrm{four}}^2$$

; $$h_8^2$$

; $$h_5^3$$

; $$h_6^{\mathrm{four}}$$

; $$h_7^5$$

and $$h_8^6$$

according to the expression $$h_j^i=h_{\mathrm{one}}^i/h_{\mathrm{one}}^j$$

, i, j = 2, 3, ..., 8, $$i\ne j$$

. 5. The amplitude direction finder according to claim 2, characterized in that the third computer determines the estimated values of the direction of arrival of the signal φ in accordance with the expressions:

where p is the number of the antenna element selected as the reference. 6. An amplitude direction finder comprising an antenna system, a radio receiver, a first calculator and an indication unit, characterized in that an additional clock, an eight-channel analog-to-digital converter, a series-connected adder, a maximum search unit, a decoder, a second calculator and an averaging unit are added, a group the information outputs of which are connected to the group of information inputs of the display unit, and the group of information inputs of the adder is connected to the group of information outputs of the first the first computer and the second group of information inputs of the decoder, the group of information inputs of the eight-channel analog-to-digital converter is connected to the group of information outputs of the radio receiver made by the eight-channel, and the group of information outputs is connected to the group of information inputs of the first computer, the output of the clock generator is connected to the clock input of the eight-channel analog digital converter, synchronization inputs of the first and second computers, averaging unit, adder, poi block ska of the maximum and the decoder, and the information inputs of the eight-channel radio receiver are connected to the outputs of the corresponding antenna elements of the antenna system. 7. The amplitude direction finder according to claim 6, characterized in that the antenna system is made of eight antenna elements evenly spaced around a cylindrical reflector. 8. The amplitude direction finder according to claim 7, characterized in that the first calculator determines the ratio of signal levels in four antenna elements diametrically spaced from each other $$h_5^{\mathrm{one}}$$

; $$h_6^2$$

; $$h_7^3$$

and $$h_8^{\mathrm{four}}$$

as well as in fourteen pairs of elements $$h_3^{\mathrm{one}}$$

; $$h_7^{\mathrm{one}}$$

; $$h_{\mathrm{four}}^2$$

; $$h_8^2$$

; $$h_5^3$$

; $$h_6^{\mathrm{four}}$$

; $$h_7^5$$

; $$h_6^8$$

; $$h_{\mathrm{one}}^8$$

; $$h_{\mathrm{one}}^2$$

; $$h_7^8$$

; $$h_6^5$$

; $$h_7^6$$

and $$h_2^3$$

according to the expression $$h_j^i=U_i/U_{\mathrm{one}}$$

, where U _i , U _j are the signal levels at the outputs of the i-th and j-th elements, respectively, i, j = 1, 2, 3, ..., 8, $$i\ne j$$

. 9. The amplitude direction finder according to claim 7, characterized in that the second computer determines the estimated values of the direction of arrival of the signal φ in accordance with the expressions:

where p is the number of the antenna element selected as the reference.

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