Signal processing method to avoid deception attack and apparatus for performing the same
View Patent ↗A signal processing method to avoid deception attack and apparatus for performing the same are provided. The signal processing method includes generating a synthesized signal by receiving a signal from a satellite, detecting a deception signal from the synthesized signal based on tracking information on a signal currently being tracked, separating a normal navigation signal from the synthesized signal in response to the detecting of the deception signal, and computing a normal navigation solution based on the normal navigation signal.
1 . A signal processing method to avoid a deception attack, the method comprising:
generating a synthesized signal by receiving a signal from a satellite;
detecting a deception signal from the synthesized signal based on tracking information on a signal currently being tracked;
separating a normal navigation signal from the synthesized signal in response to the detecting of the deception signal; and
computing a normal navigation solution based on the normal navigation signal,
wherein the separating of the normal navigation signal comprises:
determining whether the normal navigation signal is separated from the synthesized signal; and
generating tracking information on the normal navigation signal when the normal navigation signal is determined to have been separated from the synthesized signal.
2 . The method of claim 1 , wherein the tracking information comprises a code location and Doppler information of the signal currently being tracked.
3 . The method of claim 1 , wherein the detecting of the deception signal comprises:
calculating signal intensity correlation values of signals included in the synthesized signal; and
determining whether the deception signal is included in the synthesized signal based on the signal intensity correlation values.
4 . The method of claim 3 , wherein the calculating of the signal intensity correlation values comprises calculating the signal intensity correlation values of the signals included in the synthesized signal within a predetermined code location range, based on a code location of the signal currently being tracked.
5 . The method of claim 3 , wherein the determining of whether the deception signal is included in the synthesized signal comprises determining, as the deception signal, a signal which has a signal intensity correlation value greater than a signal intensity correlation value of the signal currently being tracked among the signals included in the synthesized signal.
6 . The method of claim 4 , wherein the determining of whether the deception signal is included in the synthesized signal further comprises:
setting a deception detect flag to a first state when the deception signal is included in the synthesized signal; and
setting the deception detect flag to a second state when there is no signal which has a signal intensity correlation value greater than a signal intensity correlation value of the signal currently being tracked among the signals included in the synthesized signal.
7 . The method of claim 6 , further comprising detecting the deception signal again in response to the deception detect flag being in the second state.
8 . The method of claim 1 , wherein the determining of whether the normal navigation signal is separated comprises determining whether a distribution of signal intensity correlation values of the normal navigation signal maintains a predetermined shape and determining whether the normal navigation signal is separated.
9 . The method of claim 8 , wherein the distribution of the signal intensity correlation values of the normal navigation signal comprises a distribution of Early-Prompt-Late correlation values.
10 . An apparatus for signal processing to avoid a deception attack, the apparatus comprising:
a converter configured to generate a synthesized signal by receiving a signal from a satellite; and
a signal processor configured to detect a deception signal from the synthesized signal based on tracking information on a signal currently being tracked, separate a normal navigation signal from the synthesized signal, and generate a normal navigation solution based on the normal navigation signal,
wherein when separating the normal navigation signal, the signal processor is configured to:
determine whether the normal navigation signal is separated from the synthesized signal; and
generate tracking information on the normal navigation signal when the normal navigation signal is determined to have been separated from the synthesized signal.
11 . The apparatus of claim 10 , wherein the tracking information comprises a code location and Doppler information of the signal currently being tracked.
12 . The apparatus of claim 10 , wherein the signal processor is configured to:
calculate signal intensity correlation values of signals included in the synthesized signal; and
determine whether the deception signal is included in the synthesized signal based on the signal intensity correlation values.
13 . The apparatus of claim 12 , wherein the signal processor is configured to calculate the signal intensity correlation values of the signals included in the synthesized signal within a predetermined code location range, based on a code location of the signal currently being tracked.
14 . The apparatus of claim 12 , wherein the signal processor is configured to determine, as the deception signal, a signal which has a signal intensity correlation value greater than a signal intensity correlation value of the signal currently being tracked among the signals included in the synthesized signal.
15 . The apparatus of claim 13 , wherein the signal processor is configured to:
set a deception detect flag to a first state when the deception signal is included in the synthesized signal; and
set the deception detect flag to a second state when there is no signal which has a signal intensity correlation value greater than a signal intensity correlation value of the signal currently being tracked among the signals included in the synthesized signal.
16 . The apparatus of claim 15 , wherein the signal processor is configured to detect the deception signal again in response to the deception detect flag being in the second state.
17 . The apparatus of claim 10 , wherein the signal processor is configured to determine whether a distribution of signal intensity correlation values of the normal navigation signal maintains a predetermined shape and determine whether the normal navigation signal is separated.
18 . The apparatus of claim 17 , wherein the distribution of the signal intensity correlation values of the normal navigation signal comprises a distribution of Early-Prompt-Late correlation values.