Abstract: A method for generating deception target information is proposed. The method may include setting third transmission sources pre-selected based on movement path of a jammer as jamming channels, setting a passive radar reference position according to presence or reliability of prior information on position of the passive radar. The method may also include grouping set jamming channels into groups according to operating environment and purpose and analyzing a deception target settable area based on positions of the third transmission sources, the passive radar reference position, and a movement path of the actual target. The method may further include setting a deception target movement path and deriving the deception target information based on the passive radar reference position, the positions of the third transmission sources, the movement path, and a movement path of a virtual deception target for each deception target movement path.

Abstract: A method and an apparatus for detecting a defect based on a phased pass/fail determination are disclosed. According to at least one aspect of the present disclosure, a method comprising: a process of acquiring a product image which is an image of the product; a first determination process of inputting the product image into a first determination model to perform a pass/fail determination for the product; and a second determination process of inputting the product image into a second determination model to perform a pass/fail determination for the product when the product is determined to be undeterminable as a result of the pass/fail determination of the first determination process.

Abstract: A frequency estimation apparatus and method for a single receiver. The frequency estimation apparatus for the single receiver includes: a coarse frequency estimation unit estimating a coarse frequency by calculating an average of frequency estimation values for each single pulse; a direct current domain transformation unit transforming a reception signal into a direct current domain based on the coarse frequency; a fine frequency estimation unit estimating a fine frequency by applying regression analysis to a pulse train in the direct current domain of the coarse frequency; and an extremely fine frequency estimation unit estimating an extremely fine frequency by compensating an error of the coarse frequency with the fine frequency.

Abstract: A frequency estimation apparatus and method for a single receiver. The frequency estimation apparatus for the single receiver includes: a coarse frequency estimation unit estimating a coarse frequency by calculating an average of frequency estimation values for each single pulse; a direct current domain transformation unit transforming a reception signal into a direct current domain based on the coarse frequency; a fine frequency estimation unit estimating a fine frequency by applying regression analysis to a pulse train in the direct current domain of the coarse frequency; and an extremely fine frequency estimation unit estimating an extremely fine frequency by compensating an error of the coarse frequency with the fine frequency.

Abstract: A method and device for recognizing a pulse repetition interval (PRI) modulation type of a radar signal are provided. The method for recognizing a pulse repetition interval (PRI) modulation type includes: extracting time of arrival (TOA) information of pulses aligned in time order from a received radar signal; generating a PRI sequence based on a difference of adjacent TOAs in the TOA information of pulses; generating a difference of PRIs (DPRI) sequence by using a difference of the adjacent PRIs in the PRI sequence; generating respective symbol sequences by using specific partition rules from the PRI sequence and the DPRI sequence; and calculating characteristic factors from the symbol sequences, and comparing the characteristic factors with threshold values for discriminating a PRI modulation type to determine the PRI modulation type. Thus, the PRI modulation type, a promising feature for radar signal identification, can be precisely derived.

Abstract: A method and device for recognizing a pulse repetition interval (PRI) modulation type of a radar signal are provided. The method for recognizing a pulse repetition interval (PRI) modulation type includes: extracting time of arrival (TOA) information of pulses aligned in time order from a received radar signal; generating a PRI sequence based on a difference of adjacent TOAs in the TOA information of pulses; generating a difference of PRIs (DPRI) sequence by using a difference of the adjacent PRIs in the PRI sequence; generating respective symbol sequences by using specific partition rules from the PRI sequence and the DPRI sequence; and calculating characteristic factors from the symbol sequences, and comparing the characteristic factors with threshold values for discriminating a PRI modulation type to determine the PRI modulation type. Thus, the PRI modulation type, a promising feature for radar signal identification, can be precisely derived.

Abstract: Disclosed is a radar signal clustering method using frequency modulation characteristics and combination characteristics of signals including: a first step of assigning pulses of received radar signals to cells consisting of parameters including radio frequency (RF) and angle of arrival (AOA) of the pulses; a second step of calculating a pulse density distribution of each cell using a kernel density estimator; a third step of extracting a corresponding cell as a frequency fixed cluster if the calculated pulse density distribution is greater than a threshold of the frequency fixed cluster; a fourth step of making cell groups by merging remaining cells that are not extracted as the frequency fixed clusters; a fifth step of calculating a pulse density distribution of each cell group by using the kernel density estimator for each cell group; and a sixth step of comparing the calculated pulse density distribution for each cell group with each threshold according to a signal combination type of frequency agile clus