KR20110039089A - Method for estimating three demensional multi-baseline angle of arrival, and device using the same - Google Patents

Abstract

PURPOSE: A method and device for estimating 3D multi-baseline direction is provided to reduce an amount of memories for storing data by making lookup table data through an Euler angular transformation. CONSTITUTION: Three or more receivers(110) receive a wireless signal from a wireless signal source. A phase detector(120) receives a wireless signal from two receivers. A phase difference between wireless signals is outputted. A calculating unit(430) receives the phase difference and calculates AOA(Angle of Arrival) by referring to a direction detecting lookup table. A direction detecting lookup table(440) stores data using an Euler angular transformation.

Description

METHOD FOR ESTIMATING THREE DEMENSIONAL MULTI-BASELINE ANGLE OF ARRIVAL, AND DEVICE USING THE SAME}

The present invention relates to a three-dimensional multibaseline orientation estimation method that can be used in ESM / ELINT (Electronic Support Measures / ELectronics INTelligence), in particular a wireless signal source using Euler angle transformation for phase difference. A method and apparatus for estimating the direction of a.

In general, there are two ways to detect the direction in which the electromagnetic source is located. The first method is to receive the signals emitted by the electromagnetic source to a plurality of receivers, to compare the magnitude of the received signals, and the second method is to compare the phase of the received signals.

In particular, a method of detecting an angle of arrival (AOA) through a phase difference between signals received by an array receiver is known to have a higher resolution than a method of comparing sizes.

FIG. 1 is a block diagram of a phase comparison direction detection device including a three-dimensional multibaseline direction detection array receiver used in an ESM / ELINT system.

The direction detecting device is for measuring the angle of arrival AOA between the boresight (optical axis of the directional receiver) and the incident radio signal 100.

As illustrated in FIG. 1, the direction detecting apparatus includes a receiver 110, a phase detector 120, an AOA calculator 130, and a direction lookup table 140.

In addition, the direction detecting apparatus used four receivers, and the distances between the receivers are d ₁₂ , d _34, and d _14, respectively.

The operation of the direction detecting device will be described below.

₁₂,

₃₄ 및

₁₄ 를 출력한다.When the radio signal 100 is received by each receiver 110, the phase difference of the signal in the phase detector 120 of each reception channel

₁₂ ,

₃₄ and

Print ₁₄

When the phase difference error is not included in the output through the phase detector 120, the output phase difference is expressed by Equation 1 below.

here,

λ : wavelength of the received signal

d _ij : distance between the i th receiver and the j th receiver

AOA : Azimuth angle of the signal

to be.

₁₂를 x축으로,

₃₄를 y축으로,

₁₄를 z축으로 하는 점으로 도시하였다.2 is an exemplary view of an output phase difference shown in three dimensions. 2 is a phase difference according to Equation 1 for each AOA;

₁₂ on the x-axis,

₃₄ on the y axis,

₁₄ is shown as a point on the z-axis.

The output phase differences have information on the AOA of the wireless signal source, and thus the AOA of the wireless signal source can be obtained using the output phase differences.

^h ₁₂,

^h ₃₄ 및

^h ₁₄와 수직편파의 위상차

^v ₁₂,

^v ₃₄ 및

^v ₁₄를 모두 고려하여야 한다. 상기 수평편파는 진행방향에 대해 수평방향으로 진동하는 전파이고, 상기 수직편파는 진행방향에 대해 수직방향으로 진동하는 전파이다.The direction finder must obtain the AOA by receiving a signal regardless of the polarization characteristics. Therefore, the direction detecting device calculates the phase difference of the horizontal polarization of the received signal when obtaining the AOA.

^h ₁₂ ,

^h ₃₄ and

phase difference between ^h ₁₄ and vertical polarization

^v ₁₂ ,

^v ₃₄ and

^v shall consider all of the _14. The horizontal polarized wave is a radio wave oscillating in the horizontal direction with respect to the traveling direction, and the vertical polarized wave is a radio wave oscillating in the vertical direction with respect to the traveling direction.

In order to obtain the AOA through the phase difference, the direction lookup table 140 is generally used.

3 illustrates a configuration of a direction lookup table according to the prior art.

When the radio signal 100 is radiated with a specific frequency f 310, signal strength A 320 and AOA 330, the frequency f 310, the signal strength A 320, and the AOA 330 And phase difference data 340 of the signal received through the direction detecting apparatus as one row of the direction detecting lookup table 140. As described above, in order to consider both the horizontal polarization and the vertical polarization of the received signal, the phase difference data 340 is an average value of the phase difference of the horizontal polarization and the phase difference of the vertical polarization.

₁₂ = (

^h ₁₂ +

^v ₁₂) / 2 이고,

₃₄ = (

^h ₃₄ +

^v ₃₄) / 2 이며,

₁₄ = (

^h ₁₄ +

^v ₁₄) / 2 이다.In other words,

₁₂ = (

^h ₁₂ +

^v ₁₂ ) / 2,

₃₄ = (

^h ₃₄ +

^v ₃₄ ) / 2,

₁₄ = (

^h ₁₄ +

^v ₁₄ ) / 2.

In order to obtain the AOA 330 through the phase difference, as shown in FIG. 3, the direction detection lookup table 140 may have a frequency f _n 310, a signal strength A _n 320, and an AOA 330. It should store the phase difference measurement for. In order to make the direction detection lookup table 140 more precise, temperature and the like may be included as an item of the direction detection lookup table 140.

A procedure for obtaining an AOA using the direction lookup table 140 according to the prior art is as follows.

First, the area according to the frequency f and the signal strength A of the received signal is determined. For example, in the direction lookup table 140 of FIG. 3, the area 350 when the frequency is f ₁ and the signal strength is A ₁ is illustrated by a dotted line.

Next, the phase difference data value of the region 350 is found to match or closest to the phase difference of the received signal. The AOA value of the row to which the value belongs is the AOA of the radio signal 100.

Direction detection devices used in ESM / ELINT and the like perform direction detection in a wide frequency range.

The lookup table 140 of the direction detecting apparatus according to the related art should store data of the frequency 310, the signal strength 320, the AOA 330, and the output phase difference 340. Therefore, the direction lookup table 140 needs to store a large amount of data.

In addition, when obtaining the AOA of the received radio signal 100, the AOA operator 130 must perform many operations such as comparing the output phase difference and the data of the lookup table 140 using the lookup table 140. .

The present invention is intended to solve the above problems with the prior art.

Accordingly, an object of the present invention is to provide a three-dimensional multibaseline direction detection method and apparatus for reducing the amount of data in the lookup table required for direction detection and reducing the number of operations performed in the direction detection.

The direction detecting method using the Euler angle transformation according to the present invention comprises the steps of receiving a radio signal from a radio signal source through three or more receivers, and measuring an output phase difference between radio signals received through two of the receivers. Step of Euler angle transforming the output phase difference to generate Euler angle transformed output phase difference and estimating the direction of a wireless signal source using the Euler angle transformed output phase difference and lookup table stored data; The lookup table stored data may be classified according to a group representing a specific section of the AOA of the radio signal source.

The method may further include generating lookup table stored data using the Euler angle transformed output phase difference, and storing the generated lookup table stored data in a lookup table.

Preferably, the output phase difference is characterized in that the average value of the phase difference of the horizontal polarization and the vertical polarization of the received radio signal.

Preferably, the group is determined according to a multiple of 2π periods in the relationship between the output phase difference between two specific receivers and the AOA of the radio signal.

Preferably, the lookup table stored data includes an average value of an average change value of the output phase difference between the two specific receivers, the output phase difference except the output phase difference between the two specific receivers, and the mean value of the Euler angle conversion for the group. It characterized in that it comprises a 2π cycle multiple.

Preferably, the step of estimating the direction of the radio signal source, wherein the Euler angle transformed output phase difference of the output phase difference except for the output phase difference between the two specific receivers, the average value of each group of the lookup table stored data Comparing with and, selecting a group to be replaced by the group having the nearest average value as a result of the comparison, replacing the output phase difference except for the output phase difference between the two specific receivers with the nearest average value, Performing an inverse transform on the replaced nearest average value to obtain an inverse transformed value, removing the average variation value of the group to be replaced from the inverse transformed value, and obtaining a value from which the average variation value is removed and the average variation The value with the value removed and the 2π period multiple of the group to be replaced. , And a step of computing the AOA with the relationship between the output phase and the AOA of the radio signal.

Preferably, the two specific receivers are two receivers that are farthest from each other.

The direction detecting apparatus using the Euler angle transformation according to the present invention, receiving the radio signal received from two or more receivers, two of the receivers receiving a radio signal from a radio signal source and outputs a phase difference between the radio signals A phase detector configured to receive the phase difference, calculate an AOA of the wireless signal source with reference to a direction lookup table, and the direction lookup table for storing data using Euler angle transformation; The data is characterized in that classified according to the group representing a particular section of the AOA.

Preferably, the phase difference is an average value of the phase difference between the horizontal polarization and the vertical polarization between the horizontal polarization of the radio signal.

Preferably, the stored data of the lookup table is classified according to a group, wherein the group is determined according to a multiple of 2π periods in the relationship between the output phase difference between two specific receivers of the two receivers and the AOA of the radio signal. It is characterized by.

Preferably, the lookup table stored data includes an average value of an average change value of the output phase difference between the two specific receivers, the output phase difference except the output phase difference between the two specific receivers, and the mean value of the Euler angle conversion for the group. It characterized in that it comprises a 2π cycle multiple.

Preferably, the calculation of the AOA compares the Euler angle transformed output phase difference of the remaining output phase difference except the output phase difference between the two specific receivers with the average value of the group of the lookup table stored data, Selecting a group to be replaced by the group having the closest average value, replacing the output phase difference except the output phase difference between the two specific receivers with the closest average value, and performing an inverse transform on the replaced nearest average value Obtaining an inverse transformed value, removing the mean variation value of the group to be replaced from the inverse transformed value to obtain a value from which the average variation is removed, and a value from which the average variation is removed and the 2π period of the group to be replaced Using the relationship between the output phase difference and the AOA of the radio signal as a multiple value It is characterized by obtaining the AOA.

Preferably, the two specific receivers are two receivers that are farthest from each other.

As described above in detail, the conventional invention used the direction detection lookup table 140 composed of frequency, signal strength, AOA and corresponding output phase difference values. However, since the present invention creates the lookup data using data through Euler angle transformation, the lookup table required for the direction detection is configured with less data than in the prior art. Thus, the amount of memory required for data storage is reduced.

In addition, since the data constituting the lookup table is reduced, the number of operations such as the comparison of the value between the output phase difference and the data of the lookup table during direction detection is reduced. Therefore, the time required for AOA calculation can also be shortened.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

Like reference numerals denote like elements throughout the drawings.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, except to exclude other components unless otherwise stated. In addition, the terms "... unit", "... group", "module", etc. described in the specification mean a unit for processing at least one function or operation, which is hardware or software or a combination of hardware and software. It can be implemented as.

The present invention is applied to a three-dimensional multibaseline direction detection method and apparatus. However, the present invention is not limited thereto and may be applied to any direction detecting method and apparatus to which the technical spirit of the present invention can be applied.

First, the configuration of a phase comparison direction detection apparatus using Euler angle transformation according to an embodiment of the present invention will be described. 4 is a block diagram of a phase comparison direction detection apparatus using Euler angle transformation according to an embodiment of the present invention.

As shown in FIG. 4, the direction detecting apparatus includes a direction detecting lookup prepared using a receiver 110, a phase detector 120, an operation unit 430 performing an operation using a direction detecting lookup table, and an Euler angle transformation. Table 440. The configuration of the direction detecting apparatus includes a direction detecting lookup table 440 storing data using Euler angle transformation and an arithmetic unit 430 performing the calculation using the direction detecting lookup table when compared to the apparatus of FIG. 1. To have.

Hereinafter, an arithmetic lookup table 440 storing data using the Euler angle transformation is a direction detection lookup table 440 or a lookup table 440, and an arithmetic unit 430 which performs calculation using the direction detection lookup table. The operation unit 430 is called.

In the following, the relationship between Euler angle transformation and AOA and output phase difference used for the practice of the present invention will be described using Equations 2 to 13, and the like.

^e _ij )을 포함한다.The above-described AOA and output phase difference have a relationship as shown in Equation 2 below. Equation 2 is a term (2πk _j ) and a phase difference error term (

^e _ij ).

The retardation error term means a retardation error caused by device characteristics inside the direction detecting device and environmental factors outside.

here,

λ : wavelength of the received signal

d _ij : distance between the i th receiver and the j th receiver

k _j = round ( d _ji sinθ / λ ) ("round ()" is the rounding function.)

^e _ij : i번째 수신기와 j번째 수신기로 수신되는 신호 사이의 위상차 오차

^e _ij : phase difference error between the signal received by the i th receiver and the j th receiver

to be.

₁₂ 축과

₃₄ 축에 대한 변환 행렬이 필요하다. 상기 변환 행렬은 아래의 수학식 3으로 정의된다.To do Euler angle conversion

_{With 12} axes

_We need a transformation matrix for ₃₄ axes. The transformation matrix is defined by Equation 3 below.

here,

₁₂축에 오일러 각 변환을 수행하는 행렬A:

Matrix to perform Euler angle transformation on ₁₂ axes

₃₄축에 오일러 각 변환을 수행하는 행렬

B:

Matrix to perform Euler angle transformation on ₃₄ axes

to be.

₁₂에 대해서는 수신기 거리 d ₁₂ 및 d ₃₄ 를 이용하여 변환각 α를 구하고, 이에 따라 변환 행렬 A를 구한다. 또한,

₃₄에 대해서는 수신기 거리 d ₁₂ , d ₃₄ 및 d ₁₄ 를 이용하여 변환각 β를 구하고, 이에 따라 변환 행렬 B를 구한다.5 shows a method for obtaining the conversion angle. As shown in FIG.

_{For 12} , the conversion angle α is obtained using the receiver distances d ₁₂ and d ₃₄ , and accordingly, the conversion matrix A is obtained. Also,

_{For 34} , the conversion angle β is obtained using the receiver distances d ₁₂ , d _34, and d ₁₄ , and accordingly, the transformation matrix B is obtained.

Therefore, the equation for Euler angle conversion of the output phase difference is defined by Equation 4 below.

₁₂,

₃₄ 및

₁₄ 이다.That is, the product of the matrix of matrix B, matrix A, and output phase differences is Euler angle transformed phase difference.

₁₂ ,

₃₄ and

₁₄

₁₂,

₃₄)에서는 하나의 점을 이루게 된다. 여기서 x축(610)은

₁₂ 이고, y축(620)은

₃₄ 이다.6 is a diagram illustrating a result of performing Euler angle transformation when there is no phase difference error. When Euler angle transformation is performed using Equation 4 with respect to the output phase difference, the axis transformation is performed by the Euler angle transformation. As a result, the points forming the line adjacent to each other in FIG.

₁₂ ,

₃₄ ), it forms a point. Where the x-axis 610 is

₁₂ and the y-axis 620 is

₃₄

However, as described above, since the direction detecting apparatus receives a signal regardless of the polarization characteristic and obtains an AOA through the received signal, horizontal direction and vertical polarization must be considered together.

₁₂이고, y축은

₃₄이다.7 is a diagram illustrating the phase difference between received horizontally and vertically polarized signals under a constant AOA. x-axis

₁₂ , the y-axis is

₃₄

When no error is included in the output phase difference, the phase difference is represented as one point 710 as shown in FIG. 7.

However, in actual measurement, the phase difference output through the direction detecting device includes a different error value every time the measurement is made. When the measured phase difference includes an error, as shown by the solid line in FIG. 7, the output phase difference between the vertical polarization 730 and the horizontal polarization 740 measured several times forms a constant set 720. Points 730 of the rhombus in the set 720 are measurement data for the vertical polarization. Circular points 740 in the set 720 are measurement data for horizontal polarization. The square point 750 represents an average value of the measurement data of the vertical polarization and the measurement data of the horizontal polarization.

8 shows phase differences measured when horizontal and vertical polarizations are received while changing the AOA at regular intervals under the same frequency.

Each row of the table of FIG. 8 shows the results when the measurements were made with each change of AOA from -60 ° to -52 ° by 1 °. As described above, when the measurement is performed by changing the AOA within a predetermined range, the result set is referred to as a group.

₁₂,

₃₄ 및

₁₄ (810)는 각각 오차가 없는 것을 가정하였을 때의 위상차를 나타낸다.

^h ₁₂,

^h ₃₄ 및

^h ₁₄ (820)는 수평편파의 실제 위상차 측정값을 나타내고,

^v ₁₂,

^v ₃₄ 및

^v ₁₄ (830)는 수직편파의 실제 위상차 측정값을 나타낸다.

₁₂,

₃₄ 및

₁₄ (840)는 대응하는 상기 수평편파(820) 및 상기 수직편파(830)의 평균값을 나타낸다. 즉

_ij = (

^h _ij +

^v _ij) / 2 이다. AOA별 측정 평균차(870)는 상기 오차가 없을 경우의

₁₄ (850)와 상기 편파 측정값 평균

₁₄ (860)의 차이다. 평균 변동값 Δ

₁₄ (880)은 한 군에서의 모든 상기 AOA별 측정 평균차(870) 값의 평균이다.Next, each column of the table of FIG. 8 will be described.

₁₂ ,

₃₄ and

₁₄ denotes a phase difference when each assumes no error.

^h ₁₂ ,

^h ₃₄ and

^h ₁₄ (820) represents the actual phase difference measurement of the horizontal polarization,

^v ₁₂ ,

^v ₃₄ and

^v ₁₄ (830) represents the actual phase difference measurement of the vertical polarization.

₁₂ ,

₃₄ and

₁₄ (840) represents an average value of the horizontal polarization 820 and the vertical polarization 830 corresponding to each other. In other words

_ij = (

^h _ij +

^v _ij ) / 2. Measurement average difference 870 for each AOA is obtained when there is no above error.

Average of ₁₄ (850) and the polarization measurement

₁₄ 860 cars. Average change Δ

₁₄ (880) is an average of all the AOA-specific measured mean difference 870 values in a group.

Using the group average variation value described above, the relationship between the phase difference when there is no error and the measured phase difference is represented by using the average variation value formed in a specific group and the phase difference error for each phase difference as shown in Equation 5 below. Can be.

here,

₁₂, Δ

₃₄ 및 Δ

₁₄ : 출력 위상차들의 특정 군에서의 평균 변동값 Δ

₁₂ , Δ

₃₄ and Δ

₁₄ : average variation value in a specific group of output phase differences

₁₂ ^e,

^e ₃₄ 및

^e ₁₄ , 및 : 각각의 출력 위상차에서 평균 변동값을 고려하고 남은 위상차 오차

₁₂ ^e ,

^e ₃₄ and

^e ₁₄ , and: remaining phase difference error considering the average variation value at each output phase difference

to be.

When Euler angle transformation is performed on each output phase difference actually output with an error as shown in Equation 5, the result of the Euler angle transformation is composed of three items as shown in Equation 6.

As shown by dividing the rows in Equation 6, the three items are the phase difference item when there is no error, the average variation value item and the phase difference error item when there is an error.

FIG. 9 is a diagram illustrating the result of Euler angle conversion of the phase difference of the received signal, classified according to Equation 6 above.

^o ₁₂,

^o ₃₄) (910)은 출력 위상차에 오차가 없을 경우의 오일러 각 변환 값이다. 즉, 상기 점 (

^o ₁₂,

^o ₃₄) (910)은 상기 수학식 6의 상기 오차가 없을 경우의 위상차 항목에 대응한다.Point without error (

^o ₁₂ ,

^o ₃₄ ) (910) is the Euler angle conversion value when there is no error in the output phase difference. That is, the point (

^o ₁₂ ,

^o ₃₄ ) 910 corresponds to a phase difference item when the error of Equation 6 does not exist.

^o ₁₂, Δ

^o ₃₄) (960)은 평균 변동값에 따른 오일러 각 변환 값의 변동을 의미한다. 즉, 상기 (Δ

^o ₁₂, Δ

^o ₃₄) (960)은 상기 수학식 6의 상기 오차가 있을 때 평균 변동값 항목에 대응한다. 상기 (

^o ₁₂,

^o ₃₄)와 상기 (Δ

^o ₁₂, Δ

^o ₃₄)를 더하면, 수직편파와 수평편파들의 평균값인 (

₁₂,

₃₄) (950)가 된다. 값 (Δ

^e ₁₂, Δ

^e ₃₄) (970)은 오일러 각 변환된 수직편파(930) 또는 수평편파(940)의 평균 변동값을 제외한 오차를 의미한다. 즉, 상기 값 (Δ

^e ₁₂, Δ

^e ₃₄) (970)은 상기 수학식 6의 상기 위상차 오차 항목에 대응한다. 상기 평균값 (

₁₂,

₃₄) (950)에 상기 오차 (Δ

^e ₁₂, Δ

^e ₃₄) (970)를 더하면 측정된 수직편파(930) 또는 수평편파(940)의 위상차의 오일러 각 변환된 값이 된다.( Δ

^o ₁₂ , Δ

^o ₃₄ ) (960) means the variation of the Euler angle conversion value according to the mean variation value. That is, the above ( Δ

^o ₁₂ , Δ

^o ₃₄ ) 960 corresponds to an average variation value item when the error of Equation 6 exists. remind (

^o ₁₂ ,

^o ₃₄ ) and the above ( Δ)

^o ₁₂ , Δ

^o ₃₄ ), the mean value of the vertical and horizontal polarizations (

₁₂ ,

₃₄ ) (950). Value ( Δ

^e ₁₂ , Δ

^e ₃₄ ) 970 denotes an error excluding an average variation value of the Euler angle-converted vertical polarization 930 or horizontal polarization 940. That is, the value ( Δ

^e ₁₂ , Δ

^e ₃₄ ) 970 corresponds to the phase difference error item of Equation 6. The average value (

₁₂ ,

₃₄ ) Above error in 950 ( Δ

^e ₁₂ , Δ

^e ₃₄ ) 970 is equal to the Euler angle converted value of the phase difference of the measured vertical polarization 930 or horizontal polarization 940.

Thus, Euler angle converted measurement phase difference can also be divided into three items as shown in equation (6). Equation 7 below shows Euler angle converted measurement phase difference divided into three items.

here,

^o ₁₂,

^o ₃₄ : 출력 위상차에 오차가 없는 경우 오일러 각 변환 값

^o ₁₂ ,

^o ₃₄ : Euler angle conversion value when there is no error in output phase difference

^o ₁₂, Δ

^o ₃₄ : 오일러 각 변환 후 평균 변동값 Δ

^o ₁₂ , Δ

^o ₃₄ : Average change after Euler angle conversion

^e ₁₂, Δ

^e ₃₄ : 오일러 각 변환 후 위상차 오차 Δ

^e ₁₂ , Δ

^e ₃₄ : Phase difference error after Euler angle conversion

to be.

₁₂,

₃₄,

₁₄ 들을 일정한 군으로 나눌 수 있다. 예를 들면 후술할 실시예에서와 같이 상기 수학식 2의 2π주기 배수 k_j를 기준으로, 상기 k_j의 값이 같은 AOA에 대한 오일러 각 변환된 출력 위상차

₁₂,

₃₄,

₁₄를 하나의 군으로 묶을 수 있다.Euler angle converted output phase difference measured from signals with different AOAs

₁₂ ,

₃₄ ,

₁₄ can be divided into groups. For example, a period 2π, based on the multiple k _j of the expression (2) as in the embodiment to be described hereinafter, the Euler angles of the conversion of the value of the phase difference output AOA k _j

₁₂ ,

₃₄ ,

₁₄ can be grouped into one group.

₁₂,

₃₄,

₁₄를 일정한 군들로 나누었을 때, 각각의 상기 오일러 각 변환된 출력 위상차 (

₁₂,

₃₄)의 위상차 오차 (Δ

^e ₁₂, Δ

^e ₃₄) (970)가 비교적 적다면, 상기 위상차 오차 (Δ

^e ₁₂, Δ

^e ₃₄) (970)를 상기 수학식 7에서 제거하여, 상기 오일러 각 변환된 출력 위상차 (

₁₂,

₃₄)를 평균값 (

₁₂,

₃₄) (950)중 가장 가까운 값으로 대체시킬 수 있다. 즉, 도 9에서의 수직편파(930) 및 수평편파(940) 군이 이들의 평균값 좌표인 (

₁₂,

₃₄) (950)로 대체되는 것이다. 상기 설명은 아래의 수학식 8로 나타낼 수 있다.Euler angle converted output phase difference

₁₂ ,

₃₄ ,

_{When 14} is divided into groups, each Euler angle transformed output phase difference (

₁₂ ,

₃₄ difference in phase difference ( Δ

^e ₁₂ , Δ

^e ₃₄ ) If 970 is relatively small, the phase difference error ( Δ

^e ₁₂ , Δ

^e ₃₄ ) by eliminating 970 from Equation 7, wherein the Euler angle converted output phase difference (

₁₂ ,

₃₄ ) is the mean value (

₁₂ ,

₃₄ ) can be replaced with the nearest value of (950). That is, the group of vertical polarization 930 and horizontal polarization 940 in FIG.

₁₂ ,

₃₄ ) replaced by (950). The above description may be represented by Equation 8 below.

₁₂,

₃₄) (950)는 단지 평균값 중의 하나이기 때문에, 상기 (

₁₂,

₃₄) (950) 만으로는 정확한 AOA를 알아낼 수 없고. 단지 AOA가 속하는 군만을 구할 수 있다. 따라서, 정확한 AOA를 구하기 위해

₁₄는 위상차 오차등을 사용한 대체를 하지 않고, 원래의 오일러 각 변환된 출력 위상차 값을 그대로 유지한다.Replaced above (

₁₂ ,

₃₄ ) Since 950 is just one of the mean values,

₁₂ ,

₃₄ ) (950) alone can't determine the correct AOA. Only the group to which the AOA belongs can be obtained. Therefore, to find the correct AOA

₁₄ maintains the original Euler angle converted output phase difference value without making a replacement using a phase difference error lamp.

In order to find the AOA as a representative value excluding the phase difference error shown in the right term of Equation 8, an inverse transform as shown in Equation 9 below should be performed.

^' ₁₄가 정확한 AOA를 구하는데 사용된다. In calculating the AOA value, in general, if the distance between receivers is large, the phase error is less affected. Therefore, as shown in FIG. 3, the distance between the receivers is farthest.

_^"14 is used to obtain an accurate AOA.

^' ₁₄은 아래의 수학식 10과 같이 나타내어진다.When the inverse transformation according to Equation 9 is performed,

_^"14 is expressed as shown in Equation 10 below.

^' ₁₄ = ₁₄ + Δ ₁₄ + ^e' ₁₄

^{_{'14 = 14 + Δ 14 +}} e' 14

here,

to be.

^e' ₁₄ 만큼 부가된 것을 알 수 있다. Comparing the result of Equation 10 and Equation 5, the error of AOA is

^{e 'it} can be seen that the portion ₁₄ as much.

_ij 및

^e _ij가 있다. 상기 수학식 10에서, Δ

₁₄는 일정한 군에 대한 평균 변동값이며, 전술한 것과 같이 일 군에 해당하는 출력 위상차를 측정하여 알 수 있는 값이다. 따라서, 아래의 수학식 11을 통해

_ij +

^e _ij 의 값을 구할 수 있다.In the left column of Equation 2

_ij and

^{There is e} _ij In Equation 10, Δ

₁₄ is an average variation value for a certain group, and as described above, it is a value that can be known by measuring an output phase difference corresponding to one group. Therefore, through Equation 11 below

_ij +

^We can get the value of ^e _ij .

₁₄ + ^e' ₁₄ = ^' ₁₄ - Δ ₁₄

^{_{14 + e '14 =' 14}} - Δ 14

In Equation 2, when i = 1, j = 4, the following Equation 12 is obtained.

If Equation 12 is summarized with respect to AOA, Equation 13 below can be used, and AOA can be obtained through Equation 13.

An embodiment of the present invention may be divided into a portion for preparing a direction lookup table 440 using Euler angle transformation and a portion for estimating a direction of a radio signal source using the generated direction detection lookup table 440. .

A process of creating the direction lookup table 440 by applying Euler angle transformation to the output phase difference of the received signal will be described with reference to the direction lookup table creation flowchart of FIG. 10.

Preliminary measurements are required to create the direction finding lookup table 440. The author of the lookup table 440 should know the AOA of the radio signal source that emits the radio signal 100 in advance measurement. To this end, the table author must locate the radio signal source to have a particular AOA or know the AOA of the radio signal source through a separate method.

₁₂,

₃₄ 및

₁₄ 를 측정한다(S100). Next, each receiver 110 receives the radio signal 100 emitted by the radio signal source, and transmits the received signal to the phase detector 120. Channel output phase difference through each of the phase detectors 120

₁₂ ,

₃₄ and

₁₄ is measured (S100).

The direction detection lookup table 440 is composed of several rows. In order to prepare the direction lookup table, as described above, the AOA of the radio signal source should be changed and the output phase difference according thereto should be measured.

However, each time the AOA is changed, a single row is used as measurement data for the AOA, and AOAs having the same value of 2π period multiple k _j of Equation 2 are regarded as one group, and measured for each of the AOAs in the group. And combine the calculated data into a single row. That is, the direction detection lookup table 440 has one row in group units. This is to reduce the size of the direction lookup table 440. The group number is indicated by m.

₁₂,

₃₄, Δ

₁₄, k _j )로 구성된다.One row of the direction lookup table 440 is (

₁₂ ,

₃₄ , Δ

₁₄ , k _j ).

k _j is a multiple of 2π periods of the group m indicated by the rows of the lookup table 440.

₁₂,

₃₄)는 상기 m 군의 출력 위상차들을 상기 수학식 4에 따라 오일러 각 변환 하였을 때, 상기 오일러 각 변환된 값의 평균값이다.(

₁₂ ,

₃₄ ) is an average value of the Euler angle transformed values when the output phase differences of the group m are Euler angle transformed according to Equation 4.

₁₄는 상기 m 군의 출력 위상차들의 오일러 각 변환 전의 평균 변동값이다. Δ

₁₄ is an average variation value before the Euler angle transformation of the output phase differences of the m group.

₁₂,

₃₄, Δ

₁₄, k _j )를 계산하여 이를 방향탐지 룩업테이블(440)에 기록한다(S120). 이러한 작업을 모든 군에 대해 수행하면 상기 방향탐지 룩업테이블(440)의 작성이 완료된다.As described above, the calculation unit 430 for the group (

₁₂ ,

₃₄ , Δ

₁₄ , k _j ) is calculated and recorded in the direction lookup table 440 (S120). If such a task is performed for all groups, the preparation of the direction lookup table 440 is completed.

11 is an example of a measured value of AOA and its phase difference and a lookup table prepared using the same.

Even when the direction detection lookup table 440 is generated using the Euler angle transformation, phase difference data according to the frequency and signal strength of the radio signal 100 is required, but for convenience, the direction detection created under a single frequency and signal strength is illustrated in FIG. The lookup table 440 is illustrated.

^h ₁₂,

^h ₃₄ 및

^h ₁₄)과 수직편파 측정 위상차(

^v ₁₂,

^v ₃₄ 및

^v ₁₄)를 구하고, 상기 수평편파와 상기 수직편파의 평균값(

₁₂,

₃₄ 및

₁₄) 및 오일러 각 변환 값(

₁₂,

₃₄ 및

₁₄)을 계산한다. 상기 도11 에서 도시된 것처럼 군 내 모든 AOA에 대해 수평편파와 수직편파의 평균값과 그에 따른 오일러 각 변환 값을 계산하면, 오일러 각 변환 후의 평균값 (

₁₂,

₃₄)은 (122, 278)이고,

₁₄는 23이다.. 따라서, 2 번째 그룹에 해당하는 k_j,2의 값은 -6 이므로, (122, 278, 23 ,6)을 방향탐지 룩업테이블(440)에 저장한다. In FIG. 11, the AOA corresponding to the second group (m = 2) is from −51 ° to −47 °. Within this range, change the AOA in 1 ° increments,

^h ₁₂ ,

^h ₃₄ and

^h ₁₄ ) and the vertical polarization measurement phase difference (

^v ₁₂ ,

^v ₃₄ and

^v ₁₄ ), and the average value of the horizontal polarization and the vertical polarization (

₁₂ ,

₃₄ and

₁₄ ) and Euler angle conversion value (

₁₂ ,

₃₄ and

₁₄ ). As shown in FIG. 11, when the average value of the horizontal and vertical polarizations and the resulting Euler angle conversion values are calculated for all AOAs in the group, the average value after the Euler angle conversion (

₁₂ ,

₃₄ ) is (122, 278),

₁₄ is 23. Therefore, since the value of k _{j, 2} corresponding to the second group is -6, (122, 278, 23, 6) is stored in the direction lookup table 440.

Next, a process of estimating the direction of the radio signal source using the generated direction detection lookup table will be described with reference to the accompanying drawings.

₁₂,

₃₄ 및

₁₄ 를 측정할 수 있다. 연산부(430)는 측정된 출력 위상차를 가 지고 방향탐지 룩업테이블(440)을 참조하여 AOA를 계산한다.Each receiver 110 receives the radio signal 100 emitted by the radio signal source, and transmits the received signal to the phase detector 120. Channel Output Phase Difference Through Each Phase Detector

₁₂ ,

₃₄ and

₁₄ can be measured. The calculator 430 calculates the AOA by referring to the direction lookup table 440 with the measured output phase difference.

12 shows each step of estimating AOA with the output phase difference.

First, Euler angle conversion of the output phase difference by using Equation 4 (S1100)

The received output phase difference has a phase error due to the influence of external environment and device internal elements. In consideration of the phase error, the equation of Euler angle transformation is shown in Equation 6 above.

₁₂,

₃₄)을 상기 룩업테이블(440)에 저장된 데이터 (

₁₂,

₃₄)와 비교하여(S220), 상기 룩업테이블(440)에 저장된 상기 (

₁₂,

₃₄)들 중 상기 (

₁₂,

₃₄)와 가장 가까운 값을 갖는 데이터의 행을 찾고, 상기 오일러 각 변환된 위상차 값을 상기 행의 위상차 데이터로 교체한다(S230).Next, the Euler angle transformed value is compared with the data of the lookup table 440 (S210). Of Euler angle transformed phase difference calculated by Equation 6 (

₁₂ ,

₃₄ ) the data stored in the lookup table 440 (

₁₂ ,

Compared to ₃₄ ) (S220), the (stored in the lookup table 440)

₁₂ ,

₃₄ of the above (

₁₂ ,

A row of data having a value closest to ₃₄ ) is found, and the Euler angle transformed phase difference value is replaced with phase difference data of the row (S230).

In the next step, the inverse transformation is performed and the average variation is removed (S240).

'₁₄를 얻는다. 상기

'₁₄는 상기 수학식 10에서와 같이 일정한 군에 대한 평균 변동값 Δ

₁₄를 포함하고 있고, 상기 Δ

₁₄는 상기 룩업테이블(440)의 상기 행에 저장되어 있는 값 이다. 따라서 상기 수학식 11을 사용하여

₁₄ +

^e ₁₄를 구할 수 있다.Inverse transformation is performed as shown in Equation 9 to obtain an AOA.

'Get ₁₄ remind

_"14 is the average variation value for a given group, as shown in Equation 10 Δ

₁₄ , wherein Δ

₁₄ is a value stored in the row of the lookup table 440. Therefore, using Equation 11 above

₁₄ +

^e ₁₄ can be found.

₁₄ +

^e ₁₄를 구했으며, 상기 행에 2π주기 배수 k_j,m이 저장되어 있다. 따라서, 상기 수학식 13을 통해 AOA를 구할 수 있다.In a next step, AOA is calculated (S250). In the manner described above

₁₄ +

^e ₁₄ was obtained, and a 2π period multiple k _{j, m} is stored in the row. Therefore, AOA can be obtained through Equation 13.

The method according to the invention described thus far can be implemented in software, hardware or a combination thereof. For example, the method according to the present invention may be stored on a storage medium (eg, memory, hard disk, etc.) and may be implemented with codes or instructions within a software program that may be executed by a processor. . Such an implementation can be easily implemented by those skilled in the art.

In the above description of the preferred embodiments of the present invention by way of example, the scope of the present invention is not limited only to these specific embodiments, the present invention is in various forms within the scope of the spirit and claims of the present invention The present invention may be modified, changed or improved, and such modified, changed or improved forms are also within the scope of the present invention.

1 is a configuration diagram of a phase comparison direction detection device composed of a three-dimensional multibaseline direction detection array receiver used in an ESM / ELINT system.

2 is an exemplary diagram of an output phase difference shown in three dimensions.

3 is a block diagram of a direction detection lookup table according to the prior art.

Figure 4 is a block diagram of a phase comparison direction detection apparatus using the Euler angle transformation in accordance with an embodiment of the present invention.

5 is a diagram illustrating a method for obtaining a conversion angle.

6 is a view showing a result of performing Euler angle transformation when there is no phase difference error.

FIG. 7 illustrates the phase difference of received horizontally and vertically polarized signals under constant AOA.

FIG. 8 is a diagram illustrating phase differences measured when horizontal and vertical polarizations are received while changing the AOA at regular intervals under the same frequency.

9 is a diagram illustrating the result of Euler angle conversion of the phase difference of the received signal classified according to the equation (6).

10 is a flowchart for creating a direction lookup table.

11 is a view illustrating a value measured by the AOA and its phase difference and a lookup prepared using the same.

Example diagram of a table.

12 shows each step of estimating AOA with the output phase difference.

Claims (13)

Receiving via a three or more receivers a wireless signal from a wireless signal source; Measuring an output phase difference between radio signals received through two of the receivers; Euler angle transforming the output phase difference to generate an Euler angle converted output phase difference; And Estimating a direction of a wireless signal source using the Euler angle transformed output phase difference and lookup table stored data, And the lookup table stored data are classified according to a group representing a specific section of the AOA of the radio signal source. The method of claim 1, Generating lookup table stored data using the Euler angle transformed output phase difference, and storing the generated lookup table stored data in a lookup table. The method according to claim 1 or 2, And the output phase difference is an average value of a phase difference of horizontal polarization and a vertical polarization of the received radio signal. The method according to claim 1 or 2, And the group is determined according to a multiple of 2π periods in a relationship between an output phase difference between two specific receivers and the AOA of the radio signal. The method of claim 4, wherein The lookup table stored data is an average value of an average variation value of the output phase difference between the two specific receivers, the output value of the output phase difference except the output phase difference between the two specific receivers, and the 2π period multiple for the group. Direction detection method using the Euler angle conversion, characterized in that it comprises a. The method of claim 5, Estimating the direction of the wireless signal source, Comparing the Euler angle transformed output phase difference of the output phase difference other than the output phase difference between the two specific receivers with the average value of the respective groups of the lookup table stored data; Selecting a group to be replaced by the group having the nearest mean value as a result of the comparison; Replacing the output phase difference except for the output phase difference between the two specific receivers with the closest average value; Performing an inverse transform on the replaced nearest average value to obtain an inverse transformed value; Obtaining a value from which the average variation is removed by removing the average variation of the group to be replaced from the inversely transformed value; And Calculating the AOA using the relationship between the output phase difference and the AOA of the radio signal, at which the average variation is removed and the 2π period multiple value of the group to be replaced, using the Euler angle transformation. Direction detection method. The method of claim 4, wherein And the two specific receivers are two receivers having a farthest distance from each other. Three or more receivers for receiving a wireless signal from a wireless signal source; A phase detector for receiving the radio signals received from two receivers of the receiver and outputting a phase difference between the radio signals; A calculator configured to receive the phase difference and calculate an AOA of the radio signal source by referring to a direction lookup table; And And a direction detection lookup table for storing data using Euler angle transformation, wherein the data of the direction detection lookup table are classified according to a group representing a specific section of the AOA. . The method of claim 8, And the phase difference is an average value of the phase difference between the horizontal polarization and the vertical polarization of the radio signal. The method of claim 8, The stored data of the lookup table is classified according to a group, and the group is determined according to a multiple of 2π periods in a relationship between the output phase difference between two specific receivers and the AOA of the radio signal among the two receivers. A direction finder using Euler angle conversion. The method of claim 10, The lookup table stored data is an average value of an average variation value of the output phase difference between the two specific receivers, the output value of the output phase difference except the output phase difference between the two specific receivers, and the 2π period multiple for the group. Direction detecting device using the Euler angle conversion, characterized in that it comprises a. The method of claim 11, The calculation of the AOA compares the Euler angle transformed output phase difference of the remaining output phase difference except the output phase difference between the two specific receivers with the average value of the group of the lookup table stored data, and the closest average value as a result of the comparison. Select a group to be replaced by the group having a value, replace the output phase difference except for the output phase difference between the two specific receivers with the closest average value, and perform an inverse transform on the replaced nearest average value to perform an inverse transformed value Obtain a value from which the mean variation is removed by removing the average variation of the group to be replaced from the inversely transformed value, and remove the average variation from the value and remove the average variation from the 2π period multiple of the group to be replaced. The AOA is obtained by using the relationship between the output phase difference and the AOA of the radio signal. Direction-finding apparatus using the Euler angle transformation characterized in that. The method of claim 10, And the two specific receivers are two receivers having a farthest distance from each other.

Images