KR20180103780A - Multistatic passive coherent location method for estimating target location using fm network - Google Patents

Abstract

Disclosed are a method and a system for multi-static PCL target location estimation using an FM broadcast network. The system for multi-static PCL target location estimation using an FM broadcast network comprises: a receiver selection module to select an optimal receiver to estimate a location of a target among a plurality of receivers connected to an FM broadcast network and distributed on the ground; a target location estimation module to use time difference of arrival (TDOA) information of an FM signal received by the receiver selected by the receiver selection module to estimate the location of the target; and a filtering module to filter the location of the target estimated by the target location estimation module to output the filtered location of the target. According to the method and the system for multi-static PCL target location estimation using an FM broadcast network, three dimensional location information of a target is accurately calculated in real time in a complex commercial broadcast network environment to use an existing infra broadcast network to acquire accurate target information in a wide area. Specifically, expenses are reduced and realization is easy. Specifically, an optimal receiver for target location information calculation among multiple receivers is calculated in real time, and the optimal receiver is used to calculate the three dimensional location information to increase accuracy and efficiency of target information calculation.

Description

[0001] MULTISTATIC PASSIVE COHERENT LOCATION METHOD FOR ESTIMATING TARGET LOCATION USING FM NETWORK [0002]

The present invention relates to a target location estimation system and method, and more particularly, to a system and method for estimating a target location using a commercial broadcasting network, and more particularly to a system and method for estimating a multi-static PCL target location using an FM broadcasting network will be.

A technique of grasping the position of a target by using a broadcast signal of a commercial broadcasting network by a passive coherent location (PCL) method is attracting attention.

The receiver of a broadcasting signal such as an FM broadcast receives an interference signal reflected from a target. The position of the target can be estimated using TDOA (Time Difference of Arrival) based on the interference signal.

Although it is difficult to say that it is an implementation step of the technology yet, it is theoretically sufficient to estimate the target position.

In the prior art, there is not yet a concrete technique for selecting a receiver around a target and estimating the position of the target in a broadcasting network composed of one broadcasting station base station and several receivers.

A suitable algorithm for selecting a receiver that is most suitable for the target position estimation in real time is required.

In addition, a receiver of a commercial broadcasting network such as an FM broadcast receiver is usually installed on the ground. In order to track the position of a target on a three-dimensional space, the receiver needs to model the target information as three-dimensional position information.

Thus, a means for calculating accurate target information in real time by a specific optimized algorithm such as selection of a receiver and modeling of three-dimensional position information in a complex network environment is required.

10-0791239 10-1668478

An object of the present invention is to provide a multi-static PCL target position estimation system using an FM broadcasting network.

It is another object of the present invention to provide a method for estimating a multi-static PCL target position using an FM broadcasting network.

According to an aspect of the present invention, there is provided a multi-static PCL target position estimation system using an FM broadcasting network, including: a receiver selection module for selecting an optimal receiver for estimating a position of a target among a plurality of terrestrially distributed receivers connected to an FM broadcasting network; A target position estimation module for estimating a position of a target using time difference of arrival (TDOA) information of an FM signal received from the receiver selected by the receiver selection module; And a filtering module for filtering and outputting the position of the target estimated by the target position estimation module.

Here, the receiver selection module extracts the receivers in the descending order of the signal-to-noise ratios among the plurality of receivers distributed on the ground, selects the first receiver having the highest altitude and the second receiver having the lowest altitude And a third receiver having the highest signal-to-noise ratio among the receivers within the height deviation value with reference to the tertiary high-grade point divided by three is selected And selects the fourth receiver having the highest signal-to-noise ratio among the receivers within the height deviation value based on the third quadrants of the high-level quadrants.

The target position estimation module may be configured to estimate the position of the target by converting the received TDOA information into TDOA information of a three-dimensional Cartesian coordinate system of an XY plane and a YZ plane in TDOA information of a bistatic plane .

The filtering module may be configured to apply decoupled filtering to independently consider the X coordinate, Y coordinate, and Z coordinate, respectively.

According to another aspect of the present invention, there is provided a method for estimating a multi-static PCL target position using an FM broadcasting network, the method comprising: selecting a best receiver for estimating a target position among a plurality of terrestrial distributed receivers connected to an FM broadcasting network; ; Estimating a position of a target using a time difference of arrival (TDOA) information of an FM signal received from a receiver selected in the receiver selection module; The filtering module may be configured to filter and output the position of the estimated target in the target position estimation module.

The step of selecting an optimal receiver for estimating the position of a target among the plurality of receivers distributed on the ground connected to the FM broadcasting network may include selecting a receiver having a plurality of antennas Selecting a first receiver of the highest altitude height and a second receiver of the lowest altitude height among the extracted receivers, tripling the altitude difference value of the highest altitude height and the lowest altitude height, The receiver with the highest signal-to-noise ratio among the receivers within the height deviation value based on the high-order first-order points is selected and the signal-to-noise ratio among the receivers within the height deviation value based on the third- And select a higher fourth receiver.

And estimating the location of the target using the time difference of arrival (TDOA) information of the FM signal received by the target position estimation module in the receiver selected in the receiver selection module, bistatic) plane TDOA information of the three-dimensional Cartesian coordinate system of the XY plane and the YZ plane to estimate the position of the target.

The step of the filtering module filtering and outputting the position of the target estimated by the target position estimation module may be configured to apply decoupled filtering to independently consider the X coordinate, the Y coordinate, and the Z coordinate, respectively .

According to the system and method for estimating a multi-static PCL target position using the FM broadcasting network, it is possible to accurately calculate the three-dimensional position information of the target in a complex commercial broadcasting network environment in a real-time manner using an existing infra broadcasting network. It is possible to acquire accurate target information. In particular, it has advantages in cost reduction as well as ease of implementation.

Particularly, it is possible to calculate an optimal receiver for calculating target position information from among receivers of a broadcasting network in real time and to calculate the three-dimensional position information using the calculated target, thereby improving the accuracy and efficiency of target information calculation.

1 is a schematic diagram of a multi-static PCL target position estimation algorithm using an FM broadcasting network according to an embodiment of the present invention.
2 is a block diagram of a multi-static PCL target position estimation system using an FM broadcasting network according to an embodiment of the present invention.
3 is a schematic diagram of projection modeling of target information according to an embodiment of the present invention.
4 is a flowchart of a method for estimating a multi-static PCL target position using an FM broadcasting network according to an exemplary embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail to the concrete inventive concept. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals are used for like elements in describing each drawing.

The terms first, second, A, B, etc. may be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic diagram of a multi-static PCL target position estimation algorithm using an FM broadcasting network according to an embodiment of the present invention.

Referring to FIG. 1, a multi-static PCL target position estimation system 100 using an FM broadcasting network according to an embodiment of the present invention is configured to accurately calculate three-dimensional position information of a target in real time using a commercial broadcasting network such as an FM broadcasting network do.

Specifically, it is configured to go through three steps: selection of the optimal receiver 10 for target position estimation, target position estimation, and filtering.

FIG. 2 is a block diagram of a multi-static PCL target position estimation system using an FM broadcasting network according to an embodiment of the present invention, and FIG. 3 is a schematic diagram of projection modeling of target information according to an exemplary embodiment of the present invention.

2 and 3, a multi-static PCL target position estimation system 100 using an FM network according to an exemplary embodiment of the present invention includes a receiver selection module 110, a target position estimation module 120, and a filtering module 130).

Hereinafter, the detailed configuration will be described.

The receiver selection module 110 may be configured to select an optimal receiver for estimating the position of a target among a plurality of terrestrial distributed receivers 10 associated with an FM broadcast network.

More specifically, it may be configured to select four receivers 10 out of 64 receivers 10 on the ground connected to one commercial network base station.

The receiver selection module 110 is configured to select an optimal receiver 10 according to a change in altitude of a target and is configured to select four optimal receivers for target position estimation among the terrestrial receivers 10 when the target enters the detection area (10). ≪ / RTI >

Considering the receiver 10 arbitrarily distributed on the ground, in the XY plane, the receiver 10 is positioned within a service radius of about 20 km of the commercial network base station, and the distance between the receivers 10 is sufficiently large. On the other hand, it can be seen that the Z coordinate, which is the altitude information of the receiver 10, is much smaller than the distance difference value in the XY plane due to the limitation of the geographical altitude. Here, the limitation of geographical altitude can be exemplified by the elevation of high mountains such as Gyeryongsan (altitude 846m).

In order to accurately estimate the position information of the target, it is necessary to select the receiver 10 having a high signal-to-noise ratio and to select the receiver 10 considering the altitude distribution of the receiver 10.

The following describes the algorithm of selecting the receiver 10 according to the altitude diversification.

, 수신기 집합

, 높이 편차 값

를 입력받도록 구성될 수 있다.First, the receiver selection module 110 calculates a signal-to-noise ratio

, Receiver set

, Height deviation value

As shown in FIG.

보다 신호 대 잡음비가 더 큰 수신기(10)의 집합을 추출하도록 구성될 수 있다.The receiver selection module 110 first determines the signal-to-noise ratio

Can be configured to extract a set of receivers 10 with a higher signal-to-noise ratio.

The detectable receiver set thus can be expressed as: < EMI ID = 1.0 >

If the signal-to-noise ratios are sorted in descending order, the following equation (2) can be obtained.

Here, the receiver selection module 110 may be configured to select a first receiver of the highest altitude height and a second receiver of the lowest altitude height among the receiver sets extracted earlier. These can be selected by Equation (3) and Equation (4), respectively.

Then, the ternary value of the height difference between the highest altitude and the lowest altitude can be calculated by the following equation (5).

이내의 수신기(10)를 다음 수학식 6과 같이 선택하고, 선택된 수신기(10) 중에서 신호 대 잡음비가 가장 높은 제3 수신기를 수학식 7과 같이 선택하도록 구성될 수 있다.On the other hand, the receiver selection module 110 calculates the height difference value

And selects the third receiver having the highest signal-to-noise ratio among the selected receivers 10 as shown in Equation (7). &Quot; (7) "

이내의 수신기(10)를 다음 수학식 8과 같이 선택하고, 선택된 수신기(10) 중에서 신호 대 잡음비가 가장 높은 제4 수신기를 수학식 9와 같이 선택하도록 구성될 수 있다.In addition, the receiver selection module 110 calculates the height difference value < RTI ID = 0.0 >

And selects the fourth receiver having the highest signal-to-noise ratio among the selected receivers 10 as shown in Equation (9). &Quot; (9) "

The target location estimation module 120 may be configured to estimate the location of the target using the time difference of arrival (TDOA) information of the FM signal received at the receiver 10 selected by the receiver selection module 110.

Specifically, the target position estimation module 120 converts the TDOA information received from the receiver selection module 110 into TDOA information of the three-dimensional Cartesian coordinate system of the XY plane and the YZ plane in the TDOA information of the bistatic plane, As shown in FIG.

Conventionally, TDOA information is obtained on a bistatic plane, but in the present invention, three-dimensional coordinate information is required for target position estimation. And convert the TDOA information modeled in the two-dimensional bistatic plane into information in the three-dimensional Cartesian coordinate system.

,

,

로 정의하면, 수신기(10)와 표적 사이의 길이 벡터(vector)

및 송신기와 수신(10) 간의 길이 벡터

은 다음 수학식 10 및 수학식 11과 같이 정의될 수 있다.In FIG. 2, the transmitter (not shown), the receiver 10,

,

,

The length vector between the receiver 10 and the target,

And a length vector between the transmitter and the receiver (10)

Can be defined by the following equations (10) and (11).

,

로 정의하면, 각각의 길이 벡터

와 XY 평면, YZ 평면이 이루는 각은 제2코사인 법칙을 적용하여 다음 수학식 12 내지 수학식 14와 같이 산출될 수 있다.The XY plane law vector, and the YZ plane law vector, respectively

,

, Each length vector

The XY plane, and the YZ plane may be calculated by the following equations (12) to (14) by applying a second cosine law.

,

는 바이스태틱 평면에서의 길이 벡터

과 XY 평면, 길이 벡터

과 YZ 평면이 이루는 각을 나타내고,

,

는 바이스태틱 평면에서의

과 XY 평면 및 YZ평면이 이루는 각을 나타낸다.here,

,

Is a length vector in the bistatic plane

And XY plane, length vector

And the YZ plane,

,

In the bistatic plane

And the angle formed by the XY plane and the YZ plane.

TDOA information on the XY plane and the YZ plane can be obtained as shown in Equations (15) to (18) based on the angle thus calculated.

The filtering module 130 may be configured to filter and output the position of the estimated target in the target position estimation module 120. [

The filtering module 130 may be configured to apply decoupled filtering to independently consider the X coordinate, Y coordinate, and Z coordinate, respectively.

Although there are alpha-beta and kalman filters, the alpha-beta filter has poor performance in estimating the location of the target instead of low complexity. The Kalman filter has good positioning performance of the target, Is very high. To solve this trade-off, we use a decoupled Kalman filter as proposed in [8].

에서 표적의 X 좌표를 추정할 때(Y 좌표 및 Z 좌표도 동일), 뉴턴의 운동 법칙을 적용하면 다음 수학식 19의 상태 방정식을 얻을 수 있다.The decoupled Kalman filter is a Kalman filter that considers the X coordinate, Y coordinate, and Z coordinate information independently of the Kalman filter that simultaneously considers the X coordinate, Y coordinate, and Z coordinate information. time

(Assuming that the Y coordinate and the Z coordinate are the same), the state equation of the following equation (19) can be obtained by applying Newton's law of motion.

, 상태 변이 행렬

, 노이즈 벡터

는 다음 수학식 20 내지 수학식 22로 정의된다.Here, the state vector

, A state transition matrix

, Noise vector

Is defined by the following equations (20) to (22).

,

,

는 각각 X 축에서 표적의 위치, X 축에서 표적의 속도, 표적의 정보를 얻는 시간 간격, 필터 튜닝 파라미터를 나타낸다.At this time,

,

,

Represent the position of the target in the X-axis, the velocity of the target in the X-axis, the time interval at which the target information is obtained, and the filter tuning parameters.

The value obtained by measuring the X-coordinate of the target before applying the decoupling Kalman filter is defined by the following equation (23).

로 첫번째 원소 (1,1)은 표적 추정 알고리즘을 적용하여 얻은 표적의 X 좌표값을 나타내고, 두번째 원소 (2,1)은 0으로 정의한다.

은 상태 이전 행렬,

는 위치 측정 에러(error)값이며

의 성질을 가지며,

는 측정을 통해 구해진 표적의 X 축 좌표를 나타낸다.here,

The first element (1,1) represents the X coordinate value of the target obtained by applying the target estimation algorithm, and the second element (2,1) is defined as zero.

State transition matrix,

Is a position measurement error value

And,

Represents the X-axis coordinate of the target obtained through measurement.

Based on this, the state update equation is defined by the following equation (24).

는 위치 측정 후 현재 상태 벡터로 첫번째 원소 (1,1) 성분은 표적의 X 좌표값을 나타내고, 두번째 원소 (1,2) 성분은 X 축에서의 표적의 속도를 나타낸다. 마찬가지로

는 위치 측정 전 예측 상태 벡터를 나타내고,

는 칼만 필터 이득을 나타낸다.here,

(1, 1) represents the X coordinate value of the target, and the second element (1,2) represents the speed of the target in the X axis. Likewise

Represents a predicted state vector before position measurement,

Represents the Kalman filter gain.

와 위치 측정 전 예측 상태 벡터

중 더 신뢰성이 높은 값을 구하기 위해, 두 개 값의 차이에 칼만 필터 이득을 곱하여 상태 업데이트 방정식을 업데이트 하게 된다.Position measurement

And the predicted state vector

, The state update equation is updated by multiplying the difference between the two values by the Kalman filter gain.

To obtain the Kalman filter gain, we need to define the innovation covariance equation, state covariance prediction equation, and state covariance update equation. Each equation is defined by the following equations (25) to (27).

)은 위치 측정 값과 위치 추정 전 예측 상태 값의 차이로 정의되고, 이노베이션 공분산 값

은 위치 추정 에러 값,

는 위치 측정 전 예측 상태의 공분산,

는 위치 측정 후 현재 상태의 공분산을 나타낸다.Here, Innovation (=

) Is defined as the difference between the position measurement value and the predicted state value before the position estimation, and the innovation covariance value

Lt; / RTI >

Is the covariance of the predicted state before the position measurement,

Represents the covariance of the current state after the position measurement.

Each of the innovation covariances, the state covariance before and after the position estimation, and the Kalman filter gain are calculated by the following equations (28) to (31).

의 첫번째 원소 값으로 표적 추정 X 좌표를 얻을 수 있다.A given Kalman filter gain can reduce the complexity of finding a conventional coupled Kalman filter gain by scalar multiplication rather than vector multiplication. Finally, after the position measurement obtained from the state update equation,

The target estimated X-coordinate can be obtained from the first element value of the target.

4 is a flowchart of a method for estimating a multi-static PCL target position using an FM broadcasting network according to an exemplary embodiment of the present invention.

Referring to FIG. 4, the receiver selection module 110 selects an optimal receiver 10 for estimating the position of a target among a plurality of terrestrial distributed receivers 10 connected to the FM broadcasting network (S101).

At this time, the receiver selection module 110 extracts the receiver 10 in order of the signal-to-noise ratios among the plurality of receivers 10 distributed on the ground, selects the first receiver having the highest altitude among the extracted receivers 10, A second receiver with the lowest altitude height is selected, and the altitude difference value of the highest altitude height and the lowest altitude altitude is divided into three equal parts, and among the receivers 10 within the height deviation value based on the third highest altitude, To select the third receiver having the highest signal-to-noise ratio and to select the fourth receiver having the highest signal-to-noise ratio among the receivers 10 within the height deviation value based on the third quadrant.

Next, the target position estimation module 120 estimates the position of the target using the time difference of arrival (TDOA) information of the FM signal received by the receiver 10 selected by the receiver selection module 110 (S102 ).

At this time, the target position estimation module 120 converts the TDOA information received from the receiver selection module 110 into TDOA information of the three-dimensional Cartesian coordinate system of the XY plane and the YZ plane from the TDOA information of the bistatic plane, May be configured to estimate the position.

Next, the filtering module 130 filters and outputs the position of the target estimated by the target position estimation module 120 (S103).

At this time, the filtering module 130 may be configured to apply decoupled filtering to independently consider the X coordinate, Y coordinate, and Z coordinate.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the following claims. There will be.

110: receiver selection module
120: target position estimation module
130: Filtering module

Claims (4)

Selecting an optimal receiver for estimating a location of a target among a plurality of terrestrial distributed receivers connected to an FM broadcast network;
Estimating a position of a target using a time difference of arrival (TDOA) information of an FM signal received from a receiver selected in the receiver selection module;
Filtering module for filtering the location of the target estimated by the target location estimation module and outputting the filtered location.
2. The method of claim 1, wherein the step of selecting an optimal receiver for estimating a location of a target among a plurality of terrestrial distributed receivers,
Selecting a first receiver having the highest altitude and a second receiver having the lowest altitude among the extracted receivers, and selecting the second receiver having the highest altitude and the second highest altitude among the extracted receivers, Select the third receiver that has the highest signal-to-noise ratio among the receivers within the height deviation value based on the third-order high-order first-order points divided by the third altitude difference value of the lowest altitude height, And selecting a fourth receiver having the highest signal-to-noise ratio among the receivers within a height deviation value based on the received signal.
3. The method of claim 2, wherein the target position estimation module estimates a position of a target using time difference of arrival (TDOA) information of an FM signal received in each of the receivers selected in the receiver selection module,
And estimating the position of the target by converting the received TDOA information into TDOA information of a three-dimensional Cartesian coordinate system of an XY plane and a YZ plane in TDOA information of a bistatic plane. PCL target location estimation method.
3. The method of claim 1, wherein the filtering module is operable to filter and output the location of the estimated target in the target location module,
And decoupling filtering that considers the X coordinate, the Y coordinate, and the Z coordinate independently of each other.

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