KR101784607B1 - Method and Device for Removing Interference in Multi Radar System - Google Patents

Abstract

An apparatus and method for removing interference signals in a multi-radar system are disclosed. The disclosed apparatus and method eliminate interference due to side lobes and cross corrallation due to auto-corrlation output from the matched filter through repetitive calculations. The disclosed interference cancellation apparatus and method are characterized in that each radar module has a matched filter for all orthogonal codes and uses the output of all the matched filters to remove interference, in particular interference by cross- Can be effectively used in a multi-radar system using the same frequency.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an apparatus and method for removing interference signals in a multi-

The present invention relates to an apparatus and method for canceling interference signals, and more particularly to an apparatus and method for canceling interference signals in a multi-radar system.

A total of 10 weather radars are installed in Korea and each weather radar uses a different frequency band having a bandwidth of about 8 MHz to avoid mutual interference. As a result, the entire weather radar in Korea uses a wide frequency band of about 80 MHz. The demand for accurate weather forecasts is continuously increasing due to frequent weather changes, and a wider frequency band should be secured for more accurate weather forecasts. Meanwhile, as the recent rapid development of wireless information communication technology and the demand for wireless data have increased, wireless data traffic used in wireless communication devices has been rapidly increasing. In order to accommodate such data traffic, it is necessary to secure the frequency but it is expected that frequency shortage will occur due to limited frequency resources. Therefore, it is necessary to study the technology to improve the frequency utilization efficiency of the weather radar for efficient use of limited frequency resources.

In order to improve the frequency utilization efficiency, it is necessary to operate the weather radar operating in different frequency bands on the same frequency channel. In this case, interference occurs between other vapor radar signals. Therefore, it is necessary to study how to eliminate such interference.

In addition, the multi-radar system using the same frequency is expected to be used in various detection fields in addition to the weather radar in the future, and an interference cancellation method is required in this case.

An aspect of the present invention is to propose a method and apparatus capable of efficiently removing interference in a multi-radar system using the same frequency.

Another aspect of the present invention is to propose a method and apparatus capable of simultaneously eliminating interference due to cross-correlation and autocorrelation in a multi-radar system using the same frequency.

An interference signal cancellation device provided in each of a plurality of radar modules using the same frequency, the interference canceller comprising: a signal input unit for receiving a signal output from a matched filter module included in each of the multi-radar modules as an input signal in a first iteration, Wherein the matched filter module comprises all matched filters corresponding to orthogonal codes applied to each of the multiple radar modules; A matched filter selecting unit for selecting a matched filter corresponding to a signal having the largest peak value among the input signals; A peak time index detector for detecting a time index corresponding to the largest peak value; A first side lobe level at the detected time index of the selected matched filter signal and a second side lobe level at a side lobe level of a value subtracted from the detected matched filter index by the scaling variable, A side lobe level detecting unit for detecting a second side lobe level; Determining whether a difference between the first side lobe level and the second side lobe level exceeds a preset threshold value and adjusting a scaling variable when the difference does not exceed the preset threshold value, A scaling variable determiner for searching by an iterative operation; When the selected matched filter is a matched filter corresponding to a corresponding radar module for a detection signal initially set to 0, a signal obtained by applying the searched scaling variable to a peak value of the detected time index is multiplied by the detected time index A detection signal updating unit for updating the detection signal with the detection signal; And subtracting a value obtained by applying a scaling variable to an autocorrelation value in a time index of the detected peak value in the signal of the selected matched filter among the input signals, And an input signal updating unit for updating an input signal by subtracting a value obtained by adding a scaling variable to a cross correlation value in the detected time index, wherein the input signal updated by the input signal updating unit And the interference canceller is input to the loop iterative decision unit.

The loop repetition determining section determines to stop the loop repetition when the average value of the input signals in each repetition is not greater than the predetermined threshold level.

The first side lobe level is detected as follows.

는 입력 신호 중 최대의 피크값을 가지는 매치드 필터의 신호를 의미하고, m₁ 및 m₂는 사이드로브에 대한 시간 구간을 정의하기 위한 시간 인덱스이고,

은 검출된 시간 인덱스를 의미함. In the above equation,

M ₁ and m ₂ are time indexes for defining time intervals for the side lobes,

Means the detected time index.

The second side lobe level is detected as follows.

는 스케일링 변수임. In the above equation,

Is a scaling variable.

를 탐색하여 결정한다. Wherein the scaling variable determining unit determines a scaling variable satisfying the following equation

.

는 임계치를 설정하기 위해 사용되는 상수이며,

은 선택된 매치드 필터에서의 오토 코럴레이션을 의미함. In the above equation,

Is a constant used for setting a threshold value,

Means autocorrelation in the selected matched filter.

The detection signal updating unit updates the detection signal as shown in the following equation.

은 n번째 반복에서의 검출 신호를 의미하며,

은 0으로 설정됨. In the above equation,

Denotes a detection signal in the n-th iteration,

Is set to zero.

The input signal updating unit updates the input signal according to the following equation.

운 n번째 반복에서의 입력 신호를 의미함.In the above equation,

Means the input signal in the nth iteration.

According to another aspect of the present invention, there is provided a method of removing interference signals included in each of multiple radar modules using the same frequency, the method comprising: receiving a signal output from a matched filter module included in each multi- (A) receiving a signal and determining whether to perform a next iteration, the matched filter module including all matched filters corresponding to orthogonal codes applied to each of the multiple radar modules; A matched filter selecting step (b) of selecting a matched filter corresponding to a signal having the largest peak value among the input signals; A peak time index detecting step (c) of detecting a time index corresponding to the largest peak value; A first side lobe level at the detected time index of the selected matched filter signal and a second side lobe level at a side lobe level of a value subtracted from the detected matched filter index by the scaling variable, A side lobe level detection step (d) for detecting a second side lobe level that is a second side lobe level; Determining whether a difference between the first side lobe level and the second side lobe level exceeds a preset threshold value and adjusting a scaling variable when the difference does not exceed the preset threshold value, A scaling variable determining step (e) for searching by an iterative operation; When the selected matched filter is a matched filter corresponding to a corresponding radar module for a detection signal initially set to 0, a signal obtained by applying the searched scaling variable to a peak value of the detected time index is multiplied by the detected time index A detection signal updating step (f) for updating the detected signal with the detection signal of the detection signal; And subtracting a value obtained by applying a scaling variable to an autocorrelation value in a time index of the detected peak value in the signal of the selected matched filter among the input signals, And an input signal updating step (g) of updating an input signal by subtracting a value obtained by applying a scaling variable to a cross correlation value in the detected time index, wherein the input signal updated by the input signal updating unit A method for canceling an interference signal input to the step (a) is provided.

According to the present invention, there is an advantage that interference by cross-correlation and autocalibration can be simultaneously removed in a multi-radar system using the same frequency.

1 is a diagram illustrating a structure of a radar system to which an interference canceller according to an embodiment of the present invention is applied.
2 is a diagram illustrating the structure of a radar module according to an embodiment of the present invention;
3 is a block diagram illustrating a structure of an interference canceller according to an embodiment of the present invention.
4 is a flowchart showing a flow of an interference signal cancellation method in a multi-radar system according to an 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. 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, etc. may be used to describe various components, but the components 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. Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

The interference canceller in the multi-radar system of the present invention may be applied to various kinds of radar detection systems. It will be apparent to those skilled in the art that an interference signal canceller of a multi-radar system will be described by taking a weather radar system as an example, but it is also applicable to various detection systems using a radar in addition to a canonical radar system.

1 is a diagram illustrating a structure of a radar system to which an interference canceller according to an embodiment of the present invention is applied.

Referring to FIG. 1, a radar system according to an embodiment of the present invention includes a plurality of radar modules 110, 120, and 130. Although only three radar modules 110, 120, and 130 are illustrated in FIG. 1 as an example, the number of radar modules may be changed as needed.

Each radar module 110, 120, 130 uses the same frequency and transmits a signal of the same frequency to the target 140, 150, 160 and receives the reflected signal from the target.

The first radar module 110 is a radar module configured to transmit a signal to the target 1 140 and to receive the reflected signal accordingly and the second radar module 120 transmits a signal to the target 2 150 And the third radar module 130 is a radar module configured to transmit a signal to the target M 160 and to receive a reflected signal therefrom.

In order to perform the meteorological observation more efficiently, an environment in which a large number of radar modules are used for meteorological observation is required. In this case, since the radio resources are limited, the same frequency can not be used, and in the radar system shown in Fig. 1 The first to third radar modules 110, 120 and 130 transmit signals of the same frequency and receive reflection signals corresponding thereto. Each of the radar modules 110, 120, and 130 may include a separate transmitting radar antenna and a receiving radar antenna to perform transmission and reception, and a single radar antenna may simultaneously perform transmission and reception at predetermined time intervals It might be.

The first radar module 110 preferably receives only the reflected signal from the target 1 140 but may also receive the reflected signal from the target 2 150 or the target M 160, The reflected signal acts as an interference signal in terms of the first radar module 110.

The second radar module 120 preferably receives only the reflected signal from the target 2 150 but may also receive the reflected signal from the target 1 140 or the target M 160, The reflected signal from the second radar module 120 acts as an interference signal.

The present invention relates to a method and an apparatus for eliminating unwanted interference signals in an environment where multiple radar modules of the same frequency are used.

이며,

는 타겟 i의 기상 정보를 포함한다. The impulse response between the transmitted signal at each radar module i and the signal reflected by target i is the channel

Lt;

Includes weather information of the target i.

In this embodiment, the case where the first radar module removes the interference signal will be described as an example, but the method of removing the interference signal in each radar module will be the same.

1, the received signal received by the first radar module 110 may be expressed by Equation (1).

은 레이더 모듈 i로부터의 송신 신호를 의미한다. 위 수학식 1에서, 첫번째 항의

이 제1 레이더 모듈(110)에서 최종적으로 검출하고자 하는 성분이며 나머지 성분들은 모두 간섭 신호에 해당되고, n은 추후에 설명하는 반복 루프 인덱스를 의미한다. In Equation (1) above,

Means a transmission signal from the radar module i. In the above Equation 1,

The other components to be finally detected by the first radar module 110 are all interference signals, and n denotes an iterative loop index to be described later.

In the present embodiment, each radar module transmits an orthogonal code and a signal to which pulse compression is applied. To use orthogonal codes and signals with pulse compression, each radar module first removes interference using a matched filter for the received signal. However, since the orthogonal code is not ideal, not all the interference can be eliminated by only the matched filter. In this embodiment, a method of eliminating the interference to the output signal of the matched filter is proposed.

According to one embodiment of the present invention, orthogonal codes can be used that are polyphase sequences having a length of 128 and each sub-pulse having a value of one of the four phases.

2 is a diagram illustrating the structure of a radar module according to an embodiment of the present invention.

Referring to FIG. 2, a radar module according to an embodiment of the present invention includes a radar antenna 200, a matched filter module 210, and an interference canceller 220.

The radar antenna 200 transmits a signal to the target and receives a signal reflected from the target. The radar antenna 200 receives not only the reflected signal from the desired target but also the reflected signal from the other target.

The matched filter module 210 is a combination of matched filters associated with orthogonal codes applied to each radar. In general, unlike a receiving device using a matched filter, the matched filter module 210 of the present invention is capable of converting all matched filters, i.e., matched filter 1 to matched filter M corresponding to orthogonal codes applied to all radars, Radar module. In a receiving apparatus using a conventional orthogonal code, the first radar module has only a matched filter corresponding to an orthogonal code applied to the first radar module, but in the present invention, the first radar module corresponds to an orthogonal code applied to all the radar modules All matched filters are provided.

The signals received through the radar antenna 200 pass through all of the matched filters and are output independently of each other.

If an ideal orthogonal code is used, all interfering signals can be removed with only the matched filter. However, the orthogonal code is not perfect and the signal output from the matched filter still has interference components due to auto-corrlation and cross-correlation.

The ideal autocalibration value will have the form of an impulse function that senses a peak at a particular time index, but practically does not have this impulse shape and the sidelobe is distributed around the time index with the peak. In addition, the ideal cross correlation value should be 0, but practically no 0 is output in the matched filter. In the present invention, in order to solve the problem that cross-correlation is not outputted as 0 and is influenced by interference, all receivers have matched filters for all orthogonal codes, and a method for eliminating interference by cross- This will be described in detail later.

의 오토 코럴레이션과 크로스 코럴레이션은 다음의 수학식 2 및 다음의 수학식 3과 같이 정의될 수 있다. Transmission signal

The autocorrelation and the cross corrallation of the image can be defined by the following equations (2) and (3).

The output of the matched filter module in the first radar module 110 may be expressed as Equation (4).

은

의 사이드로브이다. 이상적인 직교코드가 사용된다면,

은 델타 함수이고

은 0이 될 것이고, 크로스 코럴레이션인

역시 0이 될 것이나 실질적으로 직교 코드가 이상적이지 않기에 오토 코럴레이션과 크로스 코럴레이션에 의한 간섭이 남아 있게 된다. In Equation (4) above,

silver

Of the side lobes. If an ideal orthogonal code is used,

Is a delta function

Lt; RTI ID = 0.0 > 0, < / RTI &

It will still be zero, but the orthogonal code is not ideal, so there will be interference by autocalibration and cross correlation.

The interference signal canceling device 220 functions to acquire a detection signal from which interference signals have been removed using signals output through the matched filters. The interference canceller of the present invention operates to remove both the side lobe of the remaining autocorrelation component at the output of the matched filter module 210 and non-zero cross-correlation interference.

3 is a block diagram illustrating a structure of an interference canceller according to an embodiment of the present invention.

3, the apparatus for removing interference signals according to an embodiment of the present invention includes a loop repetition determining unit 300, a matched filter selecting unit 310, a peak time index detecting unit 320, a sidelobe level detecting unit 330 A scaling variable determining unit 340, a detection signal updating unit 350, and an input signal updating unit 360.

The interference cancellation of the present invention is performed through an iterative operation, and the loop iterative determiner 300 determines whether to terminate the iterative operation. A scaled variable determining unit 340, a detected signal updating unit 350 and an output signal updating unit 360. The matched filter selecting unit 310, the peak time index detecting unit 320, the side lobe level detecting unit 330, the scaling variable determining unit 340, The arithmetic operation forms one arithmetic cycle, and the iterative determination unit 300 determines whether to repeat this arithmetic cycle or to terminate the arithmetic cycle.

As will be described later, the output signal of the matched filter module 210 is input to the interference canceller as an input signal, and the auto-correlation and cross-correlation values for the input signal are continuously removed. When the average value of the signals is equal to or less than a predetermined threshold level, the loop repetition determining unit 300 determines to terminate the iterative calculation.

The matched filter selection unit 310 compares the peak value of the input signal (the output signal of the matched filters in the first iteration and the signal in the previous iteration in the second iteration or more). Each matched filter of the matched filter module 210 independently outputs a signal, and the matched filter selection unit 300 detects peak values of respective matched filter signals among the input signals, And selects the matched filter corresponding to the largest peak value among the peak values of the matched filters.

의 시간 인덱스에서 최대값을 출력할 경우, 피크값 시간 인덱스 검출부(320)는

을 검출하는 것이다. The peak value time index detector 320 detects a time index for outputting a peak value in the selected matched filter. E.g,

The peak value time index detector 320 detects the maximum value in the time index of the < RTI ID = 0.0 >

.

The side lobe level detecting unit 330 detects a side lobe level at a time index having a peak value of a selected matched filter signal and a side lobe level at a periphery at a time index having a peak value in the selected matched filter output signal (Hereinafter referred to as a second side lobe) level of a signal obtained by subtracting the auto-correlation adjusted by the scaling variable.

로 정의한다. 결국,

는 적용된 스케일링 변수에 의해 결정되는 것이며, 본 실시예에서 스케일링 변수는

로 정의되고, 구체적으로

와 오토 코럴레이션을 곱한 값을 선택된 매치드 필터의 신호로부터 차감하여

을 획득한다. The side lobe means a signal excluding the main lobe, and the side lobe level detection unit detects the side lobe level by summing the energy of the side lobes. In this embodiment, the first side lobe level, which is the sidelobe level of the selected matched filter output signal, is defined as S, and the side lobe level of the value obtained by subtracting the autocorrelation adjusted by the scaling variable from the selected matched filter output signal The second side lobe level

. finally,

Is determined by the applied scaling variable, and in this embodiment the scaling variable is

, And specifically

And the autocorrelation is subtracted from the signal of the selected matched filter

.

의 차이가 미리 설정된 임계치 이상이 되도록 하기 위한 스케일링 변수를 결정하는 기능을 한다. S와

의 차는 오토코럴레이션에 의한 사이드로브가 적절하게 제거되었는지 여부를 판단하기 위한 척도가 될 수 있다. S와

의 차가 크다는 것은 사이드로브가 적절하게 제거되었다는 것을 의미하며, S와

의 차가 작다는 것은 사이드로브가 적절하게 제거되지 않았다는 것을 의미한다. The scaling variable determiner 330 determines S and

To be equal to or greater than a preset threshold value. S and

May be a measure for judging whether or not the side lobe by the autocorrelation has been appropriately removed. S and

A large difference means that the sidelobe has been properly removed, and S and

A small difference means that the side lobe has not been properly removed.

에 적용되는 스케일링 변수를 변경하면서 S와

의 차가 미리 설정된 임계치를 초과하기 위한 스케일링 변수

를 결정한다. The scaling variable determiner 330 determines

And the scaling variables applied to S and

Lt; RTI ID = 0.0 > a < / RTI > scaling variable

.

의 차가 미리 설정된 임계치를 초과할 경우 적용한 스케일링 변수

가 적절하다고 판단한다. 만일, S와

의 차가 미리 설정된 임계치를 초과하지 않을 경우 적용한 스케일링 변수

가 적절하지 않다고 판단한다. S and

Is greater than a predetermined threshold value, a scaling variable

Is appropriate. If S and

Is smaller than a preset threshold value, the scaling variable

Is not appropriate.

가 적절하지 않다고 판단될 경우, 스케일링 변수

를 변경하여 다시 연산된

및 S와

의 차를 획득하여 적용된 스케일링 변수

가 적절한지 여부를 판단한다. 이때,스케일링 변수

의 조절은 초기 설정 값으로부터 줄여나가는 방식으로 변경된다. Scaling variable

Is not appropriate, the scaling variable < RTI ID = 0.0 >

Lt; RTI ID = 0.0 >

And S and

To obtain the applied scaling variable

Is appropriate. At this time,

Is changed in such a manner as to be reduced from the initial set value.

의 차가 미리 설정된 임계치를 초과할 때까지 반복적으로 이루어진다. The adjustment of the scaling variable is S

Until the difference exceeds a preset threshold value.

If the peak value of the time index detected in each iteration process is a signal to be acquired by the corresponding radar module, the detection signal updating unit 350 multiplies the peak value in the corresponding time index by the scaling variable, It is determined as a detection signal of the module.

를 곱한 값을 해당 시간 인덱스에서의 검출 신호로 결정하는 것이다. In the first iteration, the detection signal of the detection signal updater is set to 0, and the detection signal is updated every time the loop is repeated. When a peak value is detected in a matched filter corresponding to an orthogonal code applied to each radar module, a plurality of radar modules are provided with a scaling variable

Is determined as a detection signal in the corresponding time index.

를 곱한 값을 해당 시간 인덱스에서의 검출 신호로 결정하는 것이다. 그러나, 제1 레이더 모듈은 제1 매치드 필터외에 다른 매치드 필터에서 피크값이 검출될 경우 해당 반복에서 별도로 검출 신호를 갱신하지는 않는 것이다. For example, when the peak value is detected in the output signal of the first matched filter for the orthogonal code applied to the first radar module, the first radar module sets a scaling variable

Is determined as a detection signal in the corresponding time index. However, the first radar module does not update the detection signal separately in the repetition when a peak value is detected in a matched filter other than the first matched filter.

From the viewpoint of the first radar module, the peak value detected in the matched filter other than the first matched filter is a signal acting as a cross-correlation to the first radar module. Since the cross corrlaration signal is preferably a signal that should be 0, the signal at the time index is not reflected in the detection signal. However, since the peak value detected by the first matched filter is an auto-correlation value to be detected by the first radar module, a signal obtained by applying a scaling variable to the peak value is determined as a detection signal.

The input signal updating unit 360 subtracts the value obtained by applying the scaling variable to the auto-correlation value in the time index of the peak value detected in the signal of the matched filter selected in the repetition, The input signal is updated to subtract the cross-correlation value to which the scaling variable is applied in the time index of the detected peak value.

That is, the input signal updating unit 360 updates the input signal so as to subtract the autocorrelation and the cross-correlation from the input signal of the repetition.

The updated input signal is input to the loop repetition determining unit 300 again, and the loop repetition determining unit 300 determines whether to repeat the next loop operation. When the next loop operation is performed, matched filter selection, peak time index detection, side lobe level detection, scaling variable determination, and detection signal update are performed on the input signal updated by the input signal updating unit 360.

FIG. 4 is a flowchart illustrating a method of removing an interference signal in a multi-radar system according to an embodiment of the present invention.

Referring to FIG. 4, a step of determining whether to continue loop repetition for an iterative operation is performed (step 400). As described above, if the average value of the input signals is equal to or higher than the predetermined threshold level, the process proceeds to the next step. Otherwise, the loop repetition is stopped and the detection signal in the repetition is determined as the final detection signal.

If it is the first iteration, the matched filter is selected from the output signal of the matched filter, and the signal that was updated in the previous iteration, if not the first iteration, corresponding to the largest peak value (step 402).

이라고 가정한다. 여기서, i는 매치드 필터 인덱스, m은 시간 인덱스, n은 반복 횟수에 대한 인덱스이다. Also, a time index corresponding to the largest peak value is detected (step 404). Input signal

. Here, i is a matched filter index, m is a time index, and n is an index for the number of repetitions.

은 다음의 수학식 5와 같이 정의될 수 있다. At this time, the time index corresponding to the largest peak value

Can be defined by the following equation (5).

을 검출한다. If a time index corresponding to the peak value is detected, side lobe level detection is performed (step 406). As described above, the first side lobe level S and the second side lobe level

.

The first side lobe level S means a side lobe level in the vicinity of a time index having a peak value at the selected matched filter output, and is defined by the following Equation (6).

는 입력 신호 중 최대의 피크값을 가지는 매치드 필터의 신호를 의미하고, m₁ 및 m₂는 사이드로브에 대한 시간 구간을 정의하기 위한 시간 인덱스이다. In Equation (6) above,

Denotes a signal of a matched filter having a maximum peak value of the input signal, and m ₁ and m ₂ are time indexes for defining a time interval for the side lobe.

The second side lobe level means the side lobe level of the signal minus auto-correlation adjusted by the scaling variable at the time index with the peak value of the selected matched filter output signal. The second side lobe level is defined as: " (7) "

가 적용되며 이때

로는 초기 설정값이 적용되며 일례로 0.9일 수 있다. The second side lobe level has a scaling variable

Is applied

The initial set value is applied, and may be 0.9, for example.

When the first side lobe level and the second side lobe level are detected, the difference between the first side lobe level and the second side lobe level is calculated (step 408), and the difference between the first side lobe level and the second side lobe level is calculated in advance It is determined whether the set threshold value is exceeded (step 410). This operation is performed as shown in Equation (8).

는 임계치를 설정하기 위해 사용되는 상수이다. In Equation (8) above,

Is a constant used to set the threshold.

를 조정한 후 다시 단계 406을 수행하게 되며, 단계 406 내지 단계 410의 루프는 단계 410의 조건을 만족할 때까지

를 조정하면서 이루어진다. If the difference between the first sidelobe level and the second sidelobe level does not exceed a preset threshold in step 410,

The loop of steps 406 to 410 is repeated until the condition of step 410 is satisfied

.

가 선택되면, 검출 신호를 갱신한다(단계 412). 피크값을 가지는 신호가 해당 레이드 모듈과 연관된 매치드 필터의 출력이 아닐 경우 검출 신호는 갱신되지 않는다. 피크값을 가지는 신호가 해당 레이더 모듈과 연관된 매치드 필터(해당 레이더 모듈에 적용된 직교 코드를 사용하는 매치드 필터)의 출력일 경우 피크값을 가지는 시간 인덱스에서의 오토 코럴레이션에 스케일링 변수를 곱한 값을 해당 시간 인덱스에서의 검출 신호로 갱신한다. 이러한 검출 신호는 매 반복 루프마다 갱신된다. The appropriate scaling variable satisfying step 410

Is selected, the detection signal is updated (step 412). The detection signal is not updated if the signal having the peak value is not the output of the matched filter associated with the corresponding raiding module. If the signal with the peak value is the output of the matched filter associated with the radar module (the matched filter using the orthogonal code applied to the radar module), multiply the auto-correlation at the time index with the peak value by the scaling variable To the detection signal in the corresponding time index. This detection signal is updated for each iteration loop.

은 0으로 설정되며, 갱신되는 검출 신호는 다음의 수학식 9와 같이 정의될 수 있다. At the first iteration,

Is set to 0, and a detection signal to be updated can be defined by the following Equation (9).

When the detection signal is updated, an input signal update is performed (step 414) to subtract the autocorrelation and the cross-correlation at the time index corresponding to the peak value detected in the repetition from the input signal in the repetition.

The update of the input signal may be performed as Equation (10).

운 n번째 반복에서의 입력 신호를 의미한다. 갱신된 입력 신호에 대해 다음 반복을 수행할지 여부를 판단하는 단계 400으로 회귀하며 갱신된 입력 신호에 대해 단계 402 내지 단계 412가 수행된다. In the above equation,

Means the input signal in the nth iteration. The process returns to step 400 for determining whether to perform the next iteration on the updated input signal, and steps 402 to 412 are performed on the updated input signal.

As described above, the present invention has been described with reference to particular embodiments, such as specific elements, and specific embodiments and drawings. However, it should be understood that the present invention is not limited to the above- Those skilled in the art will appreciate that various modifications and changes may be made thereto without departing from the scope of the present invention. Accordingly, the spirit of the present invention should not be construed as being limited to the embodiments described, and all of the equivalents or equivalents of the claims, as well as the following claims, belong to the scope of the present invention .

Claims (14)

An interference signal canceling apparatus provided in each of multiple radar modules using the same frequency,
A loop repetition determining unit that receives a signal output from the matched filter module included in each of the multiple radar modules as an input signal in a first iteration and determines whether to perform the next iteration, All matched filters corresponding to orthogonal codes applied to each of the radar modules;
A matched filter selecting unit for selecting a matched filter corresponding to a signal having the largest peak value among the input signals;
A peak time index detector for detecting a time index corresponding to the largest peak value;
A first side lobe level at the detected time index of the selected matched filter signal and a second side lobe level at a side lobe level of a value subtracted from the detected matched filter index by the scaling variable, A side lobe level detecting unit for detecting a second side lobe level;
Determining whether a difference between the first side lobe level and the second side lobe level exceeds a preset threshold value and adjusting a scaling variable when the difference does not exceed the preset threshold value, A scaling variable determiner for searching by an iterative operation;
When the selected matched filter is a matched filter corresponding to a corresponding radar module for a detection signal initially set to 0, a signal obtained by applying the searched scaling variable to a peak value of the detected time index is multiplied by the detected time index A detection signal updating unit for updating the detection signal with the detection signal; And
Wherein a value of a scaling variable is subtracted from an autocorrelation value in a time index of the detected peak value in a signal of the selected matched filter among the input signals, And an input signal updating unit for updating an input signal to subtract a value obtained by applying a scaling variable to a cross correlation value in the detected time index,
And the input signal updated by the input signal updating unit is input to the loop repetition determining unit.
The method according to claim 1,
Wherein the loop repetition determining unit determines to stop the loop repetition when the average value of the input signals in each repetition is not greater than a preset threshold level. The method according to claim 1,
Wherein the first sidelobe level is detected according to the following equation: < EMI ID = 1.0 >

In the above equation,

M ₁ and m ₂ are time indexes for defining time intervals for the side lobes,

Means the detected time index. The method of claim 3,
Wherein the second side lobe level is detected according to the following equation: < EMI ID = 1.0 >

In the above equation,

Is a scaling variable.
5. The method of claim 4,
Wherein the scaling variable determining unit determines a scaling variable satisfying the following equation

And determines the interference signal by searching for the interference signal.

In the above equation,

Is a constant used for setting a threshold value,

Means autocorrelation in the selected matched filter.
6. The method of claim 5,
Wherein the detection signal updating unit updates the detection signal according to the following equation.

In the above equation,

Denotes a detection signal in the n-th iteration,

Is set to zero.
The method according to claim 6,
Wherein the input signal updating unit updates an input signal according to the following equation.

In the above equation,

Means the input signal in the nth iteration.

An interference signal removing method for each of multiple radar modules using the same frequency,
A loop iteration decision step (a) of receiving a signal output from a matched filter module provided in each of the multi-radar modules as an input signal in a first iteration and determining whether to perform a next iteration; Comprises all matched filters corresponding to orthogonal codes applied to each of the multiple radar modules;
A matched filter selecting step (b) of selecting a matched filter corresponding to a signal having the largest peak value among the input signals;
A peak time index detecting step (c) of detecting a time index corresponding to the largest peak value;
A first side lobe level at the detected time index of the selected matched filter signal and a second side lobe level at a side lobe level of a value subtracted from the detected matched filter index by the scaling variable, A side lobe level detection step (d) for detecting a second side lobe level that is a second side lobe level;
Determining whether a difference between the first side lobe level and the second side lobe level exceeds a preset threshold value and adjusting a scaling variable when the difference does not exceed the preset threshold value, A scaling variable determining step (e) for searching by an iterative operation;
When the selected matched filter is a matched filter corresponding to a corresponding radar module for a detection signal initially set to 0, a signal obtained by applying the searched scaling variable to a peak value of the detected time index is multiplied by the detected time index A detection signal updating step (f) for updating the detected signal with the detection signal of the detection signal; And
Wherein a value of a scaling variable is subtracted from an autocorrelation value in a time index of the detected peak value in a signal of the selected matched filter among the input signals, And an input signal updating step (g) of updating the input signal so as to subtract a value obtained by applying a scaling variable to the cross correlation value at the detected time index,
Wherein the input signal updated by the input signal updating unit is input to the step (a). 9. The method of claim 8,
Wherein the step (a) decides to stop the loop iteration if the average value of the input signals in each iteration is not greater than a preset threshold level. 9. The method of claim 8,
Wherein the first side lobe level is detected according to the following equation: < EMI ID = 1.0 >

In the above equation,

M ₁ and m ₂ are time indexes for defining time intervals for the side lobes,

Means the detected time index. 11. The method of claim 10,
Wherein the second side lobe level is detected according to the following equation.

In the above equation,

Is a scaling variable. 12. The method of claim 11,
Wherein the step (e) comprises the steps of:

And determining the interference signal by searching for the interference signal.

In the above equation,

Is a constant used for setting a threshold value,

Means autocorrelation in the selected matched filter.
13. The method of claim 12,
Wherein the detection signal step (f) updates the detection signal according to the following equation.

In the above equation,

Denotes a detection signal in the n-th iteration,

Is set to zero.
14. The method of claim 13,
Wherein the input signal updating step (g) updates the input signal according to the following equation.

In the above equation,

Means the input signal in the nth iteration.

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