RU2520074C1 - Bearing measurement method and apparatus for realising said method - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: values of single bearings are grouped according to the direction of the radio-frequency source, in each of which detection features are stored and maximum values in each group which correspond to averaged directions of radio-frequency sources in each group are determined. The bearing measurement apparatus comprises series-connected antenna, consisting of L dipoles arranged on a circle and a central dipole, a switch and a unit for determining single bearings. The apparatus also includes a control unit, a unit for separate storage of detection features and an angular coordinate generator, connected to each other in a certain manner.

EFFECT: high accuracy of bearing measurement by reducing the effect of pulsed interference and subscriber switching torque.

4 cl, 5 dwg

Description

The group of inventions relates to direction finding and can be used to determine the bearing of the source (sources) of radio emission (IRI).

.A known method for determining the bearing formed from an array of single bearings (I.S. Kukes, M.E. Starik. Fundamentals of radio direction finding. - M .: Sov. Radio, 1964, pp. 510, 511, Fig. 8.56), which summarize values of single bearings and their number (the number of detection signs), and at the end of the averaging time, the average bearing value is formed as the ratio of the sum of the values of single bearings to the number of detections $$\overline{\alpha }=\frac{\mathrm{one}}{N}{\displaystyle \sum _{n=0}^{N-\mathrm{one}}{\alpha }_n\left(\mathrm{one}\right)}$$

.

The known method of direction finding is the closest in combination of essential features to the proposed method for determining the bearing.

There is also a device for determining bearing according to the patent of the Russian Federation No. 21458 for the utility model "Automatic direction finder", IPC G01S 3/02, publ. 01/20/2002, selected as a prototype, which implements this method for determining the bearing. The device contains a series-connected antenna, consisting of L vibrators located around the circumference, and a central vibrator, a switch, a unit for determining single bearings and a unit for the ratio of the sum of single bearings to the number of detection signs (averager), as well as a control unit (micro-computer).

When using this method and device for determining the bearing, the value of the parameter defined by formula (1) is significantly affected by single impulse noise and moments when the IRI (subscribers) switch from reception to transmission and vice versa. The reason is that the direction finder must be direction finding the IRI, which can be both emergency beacons and radio stations. The latter, in turn, serve to exchange messages between themselves over the air in simplex mode, i.e. one radio station is turned on for transmission, and the second for reception. After transmitting the message, the first radio station can switch to receive, and the second to transmit and continue to exchange messages in the opposite direction. In this case, the radio stations can be considered as IRI, between which messaging is performed. So, for example, if during averaging of the single angular values of the direction-finding IRI, an impulse noise occurs, then its influence will be the greater, the greater the difference in its angular value from the average value of the bearing. The same situation will arise at the time of switching subscribers, if, for example, if the number of detection signs from the first and second IRI are taken equal and they are in different directions relative to the direction finder, then the resulting bearing will correspond to the middle direction between them, where in reality there are no sources. And if we add pulse interference to this, then the value of the bearing being determined can be anything.

In addition, it is known that direction finders, which are based on algorithms based on the Doppler effect, are not able to distinguish between correlated signals from several IRIs from different directions, for this reason the signals are also not resolved, which also leads to significant errors in bearing detection.

The technical result of the group of inventions is to increase the accuracy of determining the bearing by reducing the influence of impulse noise and moments of switching subscribers.

The specified technical result is achieved by the fact that in the method for determining a bearing formed from an array of single bearings, according to the invention, the values of single bearings are grouped in the directions of the radio emission source (IRI), in each of which accumulation of detection signs is performed and maximum values in each group are determined that correspond to average directions of Iran in each group.

In addition, the values of single bearings in the directions of the IRI are grouped by converting the values of single bearings to discrete two-dimensional addresses - a matrix (K × N), the columns of which correspond to discrete angular addresses (directions), and the rows N - to the numbers of the time interval of predefined directions, in which record signs of detecting direction-finding signals and summarize the values in each column.

The accumulation of summarized detection signs is performed by convolution of a line of angular directions, each element of which is the result of the sum of the values in the corresponding column, and the maximum values corresponding to the averaged values in these groups are determined.

In the device for implementing the method, the indicated technical result is achieved in that in a device for detecting a bearing, comprising a series-connected antenna, consisting of L vibrators arranged in a circle, and a central vibrator, a switch and a unit for determining single bearings, as well as a control unit according to the invention a block for separate accumulation of signs of detection (BRNPO) and a shaper of angular coordinates were introduced, while the first output of the unit for determining single bearings is connected to information the BRNPO input, the second output of the single bearing detection unit is connected to the address inputs of the BRNPO and the angular coordinate generator, the BRNPO output is connected to the information input of the angular coordinate generator, the output of which is the output of the device, and the control inputs of the switch, the unit for determining single bearings and BRNPO are connected to outputs of the control unit.

According to the claimed method for determining a bearing, a one-dimensional array of single angular measurements (unit bearings) of length N is converted into a two-dimensional array of detection signs, the number of rows of which coincides with the duration of the original array N, and the number of columns corresponds to the number of address discrete in which row-by-line summation of these signs is performed, and then convolution. With these operations, a group of detection signs near the corner addresses of the corresponding IRI is achieved, which ensures the most accurate measurement of the bearing angle (or several if the number of signs from them is approximately equal), in the case of single impulse noise that arise from arbitrary directions, a significant effect on the position of the maximum they do not have a convolution level, for this purpose, a separate accumulation and formation unit is introduced in the device for determining the angle of the bearing instead of the averager available in the prototype spruce angular coordinates.

Therefore, in this case, it is necessary to perform separate accumulation, which can be implemented as a convolution in the angular sector in accordance with the expression

, где $$F_k={\displaystyle \sum _{m=0}^{M-\mathrm{one}}{A}_m\cdot I_{k-m}\left(2\right)}$$

where

, а М - ширина углового сектора усреднения. $$I_{k-m}=\{\begin{array}{c}\mathrm{one,}PR\mathrm{and}0\le k-m\le M\\ 0PR\mathrm{and}|\; |\; |k-m|\; |\; |>M\end{array}$$

, and M is the width of the angular sector of averaging.

The group of inventions characterized by the above essential features as of the filing date of the application is not known in the Russian Federation and abroad and meets the requirements of the criterion of “novelty”.

The applicant has not identified technical solutions having features that match the sets of distinctive features of the claimed inventions, ensuring the achievement of the claimed technical result, and therefore it can be concluded that the inventions comply with the patentability condition "inventive step".

The inventions can be implemented industrially using well-known technical means, technologies and materials and meet the requirements of the patentability conditions ″ industrial applicability ″.

The invention is illustrated by graphic materials, where figure 1 shows the cyclograms of the converted array of single bearings in a two-dimensional form of signs and the result of progressive summation; figure 2 - cyclograms of the result of the convolution of row summation and the level of half its maximum value; figure 3 shows a structural diagram of a device for determining bearings; figure 4 is a block diagram of a block of separate accumulation of signs of detection; figure 5 is a block diagram of a shaper of angular coordinates.

In the method for determining a bearing, a one-dimensional array of single angular measurements of duration N, designed to determine the average value, according to the invention:

- it is converted into a two-dimensional array, the number of rows of which coincides with the duration of the initial array N, the number of columns corresponds to the number of address samples, and the array values are ″ 1 ″ if a signal is detected, or ″ 0 ″ if a signal is not detected (in Fig. 1, the upper 14 lines);

- then these values ″ 1 ″ and ″ 0 ″ are summarized line by line, converting a two-dimensional array to a one-dimensional one, the duration of which corresponds to the number of address samples (bottom line in Fig. 1), and the array elements also take discrete values, any from 0 to N;

- further, the cyclic convolution of this array in the angular sector is calculated in accordance with expression (2) and the maximum level of the convolution function is determined (solid curve in Fig. 2);

- all inextricable values above half of this level are grouped into separate areas, and how many such inextricable areas of address values, so many IRI (in this example, there are two such areas, the first in the address range from 111 to 193, and the second from 313 to 396) ;

- in each such region, a local maximum is determined, each of which corresponds to an angular address, an ordinal number in the array (in this example, the local maximum of the first region corresponds to the address value 152, and the second region to the address value 355);

- because Since the hardware error is selected no more than 0.5 °, then in the range from 0 ° to 360 ° of the angular addresses K = 750, therefore, two address values of bearings 72.92 ° and 170.4 °, respectively, are assigned to certain address values 152 and 355, respectively.

A device for detecting a bearing, the structural diagram of which is shown in Fig. 3, includes a series-connected antenna 1, consisting of L antenna vibrators located around the circumference (8 vibrators are shown in the diagram), and one central vibrator, a switch 2, forming from L antenna signals a combined channel, and a unit 3 for determining single bearings (preliminary determination of a bearing), which implements an algorithm based on the Doppler effect, as well as a unit 4 for controlling (synchronizing) the operation of the device.

According to the invention, a block 5 for separate accumulation of detection signs (BRNPO) is introduced into the device, the block diagram of which is shown in FIG. 4, and the angle coordinate generator 6 (see FIG. 5). The first output of the unit for determining single bearings 3 is connected to the information input of BRNPO 5, the second output of the unit 3 for determining single bearings is connected to the address inputs of BRNPO 5 and the shaper 6 of the angular coordinates, and the output BRNPO 5 is connected to the information input of the shaper 6 of the angular coordinates. The control inputs of the switch 2, unit 3 for the determination of single bearings and BRNPO are connected to the outputs of the control unit 4, while the output of the shaper 6 of the angular coordinates is the output of the device.

The method for determining the bearing is implemented by the proposed device as follows.

Under the influence of the electromagnetic field, which is created by the direction-finding IRI, signals are formed on the vibrators (dipoles) of the antenna 1, the phase value of which depends on the direction of the IRI. These signals, switched by switch 2, and the signal from the central vibrator are fed to the inputs of unit 3 for determining single bearings, where the detection flag is formed: log. ″ 1 ″ - if the signal exceeds a predetermined ″ threshold ″ level, or log. ″ 0 ″ - if the signal does not exceed ″ threshold ″ level. Simultaneously with the sign (log. ″ 1 ″ or log. ″ 0 ″), a discrete address of the angular direction to the IRI is formed.

Signs of detection every time for a full analysis of the signals from the antenna vibrators with their corresponding angular addresses are received at the BRNPO 5 inputs and are written to the nth line (here, the number of lines N corresponds to the maximum possible number of averaging of preliminary bearings, and the information in the line before each record in of a new detection flag is preliminarily cleared) of the kth column, the number of which corresponds to a predefined discrete corner address, and the row number changes cyclically. After recording the sign in any memory location, including the zero value, when the signal is not detected, summation of all N rows is performed in each column (see figure 4). Thus, for each corner address (k-th column) is formed dynamically changing in time information (sets of features), which is the result of the sum in a ″ sliding window ″ (see figure 1).

The set of accumulated discrete features corresponding to the angular addresses is averaged in the "moving" angular sector (see figure 2) by the method of cyclic convolution; the result of this operation is the direction finding characteristic. In the aggregate of discrete readings of the direction-finding characteristic, the maximum value is determined, the half level of which is the “threshold” of signal demarcation. All discrete values of the direction-finding characteristic that exceed this level go to the output of block 5 without change, and values below this level are assigned zeros, which also go to the output of BRNPO 5.

, а второй $$\frac{355\cdot {360}^{\circ }}{750}={\mathrm{170,4}}^{\circ }$$

) и поступают на выход устройства (см. фиг.5). Здесь k - угловой адрес, соответствующий одному из максимальных значений выделенного массива (152 и 355), а K - длительность углового массива (750).From the BRNPO 5 output, arrays from different sources, separated by zero values, are fed to the input of the shaper 6 angular coordinates. In each of the selected arrays, the maximum value corresponding to the angular address is determined (in this example, these values are 152 and 355, respectively), which are written to the random access memory (RAM). After which they are recalculated in the shaper 6 of the angular coordinates in the corresponding angular values (for the considered example, the first bearing is $$\frac{152\cdot {360}^{\circ }}{750}$$

, and second $$\frac{355\cdot {360}^{\circ }}{750}={\mathrm{170,4}}^{\circ }$$

) and go to the output of the device (see figure 5). Here k is the angular address corresponding to one of the maximum values of the selected array (152 and 355), and K is the duration of the angular array (750).

All units of the device can be made using digital circuits of any series: registers - IR; adders - IM; comparison schemes - SP; memory - RU and RT, etc., which are available in a large assortment.

Thus, the proposed method for determining the bearing and the device for its implementation can improve the accuracy of measuring the angle of the bearing due to the separate accumulation of single signs and eliminate impulse noise from the general averaging, as well as perform direction finding of two subscribers with high accuracy.

Claims (4)

1. A method for determining a bearing formed from an array of single bearings, characterized in that the values of single bearings are grouped by the directions of the radio emission source (IRI), in each of which accumulation of detection signs is performed, and the maximum values in each group are determined, which correspond to the average directions of the IRI in each group, and the sign of detection for single bearings of the IRI is the excess of the signal by the IRI of a predetermined threshold level. 2. The method according to claim 1, characterized in that the values of single bearings in the directions of the IR are grouped by converting them into discrete two-dimensional addresses — matrices (K × N), columns K of which correspond to discrete angular addresses, and rows N correspond to numbers of the time interval previously certain single bearings, in which the signs of detection of direction-finding signals are recorded and summing the values in each column is performed. 3. The method according to claim 2, characterized in that the accumulation of summarized detection signs is performed by convolution of a row of angular directions, each element of which is the result of the sum of the values in the corresponding column, and the maximum values corresponding to the averaged values in these groups are determined. 4. A device for detecting a bearing, comprising a series-connected antenna, consisting of L vibrators located around the circumference, and a central vibrator, a switch and a unit for detecting single bearings, as well as a control unit, the central vibrator being connected directly to the unit for detecting single bearings, characterized the fact that a block of separate accumulation of detection signs (BRNPO) and a shaper of angular coordinates are introduced into it, while the sign of detection for single bearings of the IRI is exceeded if the IRI signal sets a predetermined threshold level, the first output of the single bearing detection unit is connected to the BRNPO information input, the second output of the single bearing detection unit is connected to the BRNPO address inputs and the angular coordinate generator, and the BRNPO output is connected to the information input of the angular coordinate generator, the output of which is the output devices, and the control inputs of the switch, the unit for determining single bearings and BRNPO are connected to the outputs of the control unit.

Images