Frequency diverse array(FDA)radar applies a tiny frequency offset across its adjacent transmitting array elements to generate a range-angle-dependent beampattern.The increased degrees-of-freedom(DOFs)in range domain c...Frequency diverse array(FDA)radar applies a tiny frequency offset across its adjacent transmitting array elements to generate a range-angle-dependent beampattern.The increased degrees-of-freedom(DOFs)in range domain can help improve the performance of radar in target detection,localization,and clutter suppression.Passive radar utilizes uncontrollable external signal as illuminator,which makes it difficult to apply traditional frequency diverse process method.However,the third-party illuminator such as Orthogonal Frequency Division Multiplexing(OFDM)signal usually consists of several closely spaced modulated carriers,and it has been widely selected as the illuminator for passive radar in recent years.Considering the orthogonality between even separated subcarriers,we propose a new frequency diverse process method by extracting and processing each subcarrier of received data independently and attempt to provide a range-angle dependent beampattern for OFDM passive radar.Numerical results and real data analyses verify the superiority of frequency diversity process on the received data of OFDM passive radar.展开更多
We propose a method to suppress deceptive jamming by frequency diverse array (FDA) in radar electronic coun- termeasure environments. FDA offers a new range-angle-dependent beam pattern through a small frequency inc...We propose a method to suppress deceptive jamming by frequency diverse array (FDA) in radar electronic coun- termeasure environments. FDA offers a new range-angle-dependent beam pattern through a small frequency increment across elements. Due to the coupling between the angle and range, a mismatch between the test angle and physical angle occurs when the slant range on which the beam focuses is not equal to the slant range of the real target. In addition, the range of the target can be extracted by sum-difference beam except for time-delay testing, because the beam provides a range resolution in the FDA that cannot be deceived by traditional deceptive jamming. A strategy of using FDA to transmit two pulses with zero and nonzero frequency increments, respectively, is proposed to ensure that the angle of a target can be obtained by FDA. Moreover, the lo- calization performance is examined by analyzing the Cramer-Rao lower bound and detection probability. Effectiveness of the proposed method is confirmed by simulation results.展开更多
基金the National Natural Science Foundation of China(61271400,62071335,61931015)Suzhou Science and Technology Planning Project:Key Industrial Technology Innovation(Prospective Application Research SYG202007)+2 种基金Hubei Province Technology Innovation Special Major Project(2019AAA061)Shenzhen Science and Technology Project(JCYJ20170818112037398)Hubei Province Science Fund for Creative Research Groups(2021CFA002)。
文摘Frequency diverse array(FDA)radar applies a tiny frequency offset across its adjacent transmitting array elements to generate a range-angle-dependent beampattern.The increased degrees-of-freedom(DOFs)in range domain can help improve the performance of radar in target detection,localization,and clutter suppression.Passive radar utilizes uncontrollable external signal as illuminator,which makes it difficult to apply traditional frequency diverse process method.However,the third-party illuminator such as Orthogonal Frequency Division Multiplexing(OFDM)signal usually consists of several closely spaced modulated carriers,and it has been widely selected as the illuminator for passive radar in recent years.Considering the orthogonality between even separated subcarriers,we propose a new frequency diverse process method by extracting and processing each subcarrier of received data independently and attempt to provide a range-angle dependent beampattern for OFDM passive radar.Numerical results and real data analyses verify the superiority of frequency diversity process on the received data of OFDM passive radar.
文摘We propose a method to suppress deceptive jamming by frequency diverse array (FDA) in radar electronic coun- termeasure environments. FDA offers a new range-angle-dependent beam pattern through a small frequency increment across elements. Due to the coupling between the angle and range, a mismatch between the test angle and physical angle occurs when the slant range on which the beam focuses is not equal to the slant range of the real target. In addition, the range of the target can be extracted by sum-difference beam except for time-delay testing, because the beam provides a range resolution in the FDA that cannot be deceived by traditional deceptive jamming. A strategy of using FDA to transmit two pulses with zero and nonzero frequency increments, respectively, is proposed to ensure that the angle of a target can be obtained by FDA. Moreover, the lo- calization performance is examined by analyzing the Cramer-Rao lower bound and detection probability. Effectiveness of the proposed method is confirmed by simulation results.