Disturbance signal detection apparatus and method

Patent metadata

Field	Value
Publication number	US-2016266236-A1
Application number	US-201414763465-A
Country	US
Kind code	A1
Filing date	Nov 20, 2014
Priority date	Dec 5, 2013
Publication date	Sep 15, 2016
Grant date	—

Abstract

A disturbance signal detection apparatus may comprise; a receiver configured to receive a first signal including at least one distortion signal, a continuous wave (CW) signal detector configured to detect a CW distortion signal from the first signal based on a frequency characteristic, and a filter configured to output a second signal by filtering out the detected CW distortion signal from the first signal.

First claim

1 . An apparatus for detecting a distortion signal, the apparatus comprising:
a receiver configured to receive a first signal comprising at least one distortion signal; a continuous wave (CW) signal detector configured to detect a CW distortion signal from the first signal based on a frequency characteristic; and a filter configured to output a second signal by filtering out the detected CW distortion signal from the first signal.

2 . The apparatus of claim 1 , wherein the CW signal detector is configured to convert the first signal into a frequency domain, and detect a portion satisfying a first discriminant in the frequency domain as the CW distortion signal.

3 . The apparatus of claim 2 , wherein the first discriminant is configured to discriminate a portion greater than half of a maximum absolute value of the first signal in the frequency domain as the CW distortion signal.

4 . The apparatus of claim 1 , wherein the CW signal detector is configured to additionally detect at least one of an azimuth and an elevation angle of the detected CW distortion signal.

5 . The apparatus of claim 1 , further comprising:
a direct sequence spread spectrum (DSSS) detector configured to detect a DSSS distortion signal from the second signal using a second discriminant based on a characteristic difference of a cross-correlation function.

6 . The apparatus of claim 5 , wherein the DSSS detector is configured to apply a cross-correlation function to the second signal, and obtain a maximum value among obtained cross-correlation values.

7 . The apparatus of claim 6 , wherein the DSSS detector is configured to apply a delay corresponding to the maximum value to the second discriminant and detect a portion satisfying the second discriminant as the DSSS distortion signal, and
the second discriminant is expressed by

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fil

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wherein R S fit denotes a cross-correlation function, and τ TD denotes a delay corresponding to a maximum value of a cross-correlation value.

8 . The apparatus of claim 5 , wherein the DSSS detector is configured to additionally detect a time difference of arrival (TDOA) of the detected DSSS distortion signal.

9 . The apparatus of claim 1 , further comprising:
a swept continuous wave (SCW) detector configured to detect an SCW distortion signal by verifying a presence of a time-varying frequency component through a time-frequency spectrum analysis.

10 . The apparatus of claim 1 , further comprising:
a SCW detector configured to apply a cross-correlation function to the second signal, and detect a portion having a cross-correlation value greater than a preset threshold as an SCW distortion signal.

11 . The apparatus of claim 1 , wherein the SCW detector is configured to additionally detect a TDOA of the detected SCW distortion signal.

12 . A method of detecting a distortion signal, the method comprising:
receiving, by a receiver, a first signal comprising at least one distortion signal; detecting, by a continuous wave (CW) signal detector, a CW distortion signal from the first signal based on a frequency characteristic; and outputting, by a filter, a second signal by filtering out the detected CW distortion signal from the first signal.

13 . The method of claim 12 , wherein the detecting comprises converting, by the CW signal detector, the first signal into a frequency domain, and detecting a portion satisfying a first discriminant in the frequency domain as the CW distortion signal.

14 . The method of claim 13 , wherein the first discriminant is configured to discriminate a portion greater than half of a maximum absolute value of the first signal in the frequency domain as the CW distortion signal.

15 . The method of claim 12 , further comprising:
detecting, by a direct sequence spread spectrum (DSSS) detector, a DSSS distortion signal from the second signal using a second discriminant based on a characteristic difference of a cross-correlation function.

16 . The method of claim 15 , wherein the detecting of the DSSS distortion signal comprises applying, by the DSSS detector, a cross-correlation function to the second signal, and obtaining a maximum value among obtained cross-correlation values.

17 . The method of claim 16 , wherein the DSSS detector is configured to apply a delay corresponding to the maximum value to the second discriminant and detect a portion satisfying the second discriminant as the DSSS distortion signal, and
the second discriminant is expressed by

R

s
fil



(

τ
TD

+
1

)

>

1
2



R

s
fil



(

τ
TD

)

,

wherein R S fit denotes a cross-correlation function, and τ TD denotes a delay corresponding to a maximum value of a cross-correlation value.

18 . The method of claim 12 , further comprising:
detecting, by a swept continuous wave (SCW) detector, an SCW distortion signal by checking a presence of a time-varying frequency component through a time-frequency spectrum analysis.

19 . The method of claim 12 , further comprising:
applying, by a SCW detector, a cross-correlation function to the second signal, and detecting a portion having a cross-correlation value greater than a

Assignees

• Korea Aerospace Res Inst

Inventors

• Kang Jae Min
• Lim Deok Won
• Heo Moon Beom

Classifications

• G01S5/04

  Position of source determined by a plurality of spaced direction-finders · CPC title

• G01S7/021 Primary

  Auxiliary means for detecting or identifying radar signals or the like, e.g. radar jamming signals · CPC title

• G01S19/21

  Interference related issues {; Issues related to cross-correlation, spoofing or other methods of denial of service} · CPC title

• G01S7/38 Primary

  Jamming means, e.g. producing false echoes · CPC title

• G01S5/06

  Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements (G01S5/12 takes precedence) · CPC title