CAJ | 학술논문

在天波超视距雷达（OTHR）中，采用短时间相干积累时，可以提高数据率和检测效能，减小电离层污染。但采用短时间相干积累时，目标信噪比往往较低，检测难度较大，而机动目标的多普勒扩展进一步增加了目标的检测难度。传统的机动目标检测算法利用基于高阶模糊函数（HAF）的多普勒补偿算法来提高机动目标的可检测性，但由于 HAF 多次用到非线性变换，而每次非线性变换都会损失部分信噪比，因此对输入信噪比要求较高，难以适应于更低信噪比环境下的机动目标检测。将机动目标回波建模为三阶多项式相位信号，采用一种低非线性度的运动参数估计方法并结合多普勒补偿算法对目标回波进行处理，仅需要一次相位降阶操作，减少了信噪比损失，降低了对输入信噪比的要求。经过仿真验证，该算法的输入信噪比门限为-3 dB，而 HAF 算法的输入信噪比门限为3 dB。
재천파초시거뢰체（OTHR）중，채용단시간상간적루시，가이제고수거솔화검측효능，감소전리층오염。단채용단시간상간적루시，목표신조비왕왕교저，검측난도교대，이궤동목표적다보륵확전진일보증가료목표적검측난도。전통적궤동목표검측산법이용기우고계모호함수（HAF）적다보륵보상산법래제고궤동목표적가검측성，단유우 HAF 다차용도비선성변환，이매차비선성변환도회손실부분신조비，인차대수입신조비요구교고，난이괄응우경저신조비배경하적궤동목표검측。장궤동목표회파건모위삼계다항식상위신호，채용일충저비선성도적운동삼수고계방법병결합다보륵보상산법대목표회파진행처리，부수요일차상위강계조작，감소료신조비손실，강저료대수입신조비적요구。경과방진험증，해산법적수입신조비문한위-3 dB，이 HAF 산법적수입신조비문한위3 dB。
Short coherent accumulation can improve the data rate and detection performance and reduce ionosphere contamination in sky-wave OTH radar.The low SNR rate is a great challenge when we detect the target using short coherent accumulation.The Doppler expansion of maneuvering target makes matter worse.The traditional detection algorithms adopt higher order ambiguity function(HAF)to compensate Doppler to improve the maneuvering target detectability.These algorithms require a higher input SNR be-cause HAF involves non-linear transformation and each non-linear transformation will reduce the SNR.So it is difficult to detect maneuvering target in lower SNR.In this paper,the echo of maneuvering target is mod-eled as a third-order polynomial phase signal.A motion parameters estimation method with low nonlinearity and Doppler compensation algorithm are used to processing target echo.The phase order is reduced only once in this algorithm.As a result,the input SNR rate is lower by using the proposed algorithm in this paper. Through simulation,the input SNR threshold of the algorithm is - 3 dB,but the threshold of HAF algo-rithm is 3 dB.