This paper proposes a multifunction radar that can not only measure sea currents but also perform sea-surface imaging.The fundamental aspect of the proposed radar comprises transmitting time-shifted up-and-down contin...This paper proposes a multifunction radar that can not only measure sea currents but also perform sea-surface imaging.The fundamental aspect of the proposed radar comprises transmitting time-shifted up-and-down continuous wave linear frequency modulated signals that allow for the offset of two one-dimensional range images of the sea surface that respectively correspond to the upward linear frequency modulated(LFM)signal and the downward LFM signal.Owing to the Doppler frequency shift from the sea surface,a range offset,which is proportional to the radial velocity of the sea surface,occurs between the upward and downward LFM signals.By using the least-squares linear fitting method in the transformed domain,the range offset can be measured and the current velocity can be retrieved.Finally,we verify the accuracy of current measurement with simulation results.展开更多
A fast iterative approach of generalized forward-backward method with the spectrum acceleration algorithm (GFBM/SAA) is developed for solving electromagnetic field integral equation and is applied to numerical simulat...A fast iterative approach of generalized forward-backward method with the spectrum acceleration algorithm (GFBM/SAA) is developed for solving electromagnetic field integral equation and is applied to numerical simulation of radar surveillance of the ship target in oceanic clutters. Randomly rough surface is realized by the Monte Carlo method using the Pierson-Moskowitz spectrum. Numerical results of bistatic and back-scattering from the ship target and oceanic clutters demonstrate the functional dependencies upon the situation of radar surveillance such as the incidence and observation angles, radar altitude, ship RCS and other oceanic conditions.展开更多
基于MLAT多点定位的A-SMGCS系统可显著提高机场场面监视的精度。对机场场面监视雷达中数据采集系统的设计方法进行详细地阐述。利用高速A/D实时采集对数放大器输出的回波数据,经F P G A处理后,通过光纤发送至信号处理。实际工作结果表明...基于MLAT多点定位的A-SMGCS系统可显著提高机场场面监视的精度。对机场场面监视雷达中数据采集系统的设计方法进行详细地阐述。利用高速A/D实时采集对数放大器输出的回波数据,经F P G A处理后,通过光纤发送至信号处理。实际工作结果表明,该设计方案成熟、可靠,为类似的系统或项目提供一个有益的借鉴。展开更多
基金The National Key Research and Development Program under contract No.2016YFC1401002the National Natural Science Foundation of China under contract Nos 41606201,41576173,41620104003 and 41706202.
文摘This paper proposes a multifunction radar that can not only measure sea currents but also perform sea-surface imaging.The fundamental aspect of the proposed radar comprises transmitting time-shifted up-and-down continuous wave linear frequency modulated signals that allow for the offset of two one-dimensional range images of the sea surface that respectively correspond to the upward linear frequency modulated(LFM)signal and the downward LFM signal.Owing to the Doppler frequency shift from the sea surface,a range offset,which is proportional to the radial velocity of the sea surface,occurs between the upward and downward LFM signals.By using the least-squares linear fitting method in the transformed domain,the range offset can be measured and the current velocity can be retrieved.Finally,we verify the accuracy of current measurement with simulation results.
基金This work was supported by the China State Key Basic Research Project (Grant No. 2001CB309405) and the National Natural Science Foundation of China (Grant Nos. 49831060 and 6012009).
文摘A fast iterative approach of generalized forward-backward method with the spectrum acceleration algorithm (GFBM/SAA) is developed for solving electromagnetic field integral equation and is applied to numerical simulation of radar surveillance of the ship target in oceanic clutters. Randomly rough surface is realized by the Monte Carlo method using the Pierson-Moskowitz spectrum. Numerical results of bistatic and back-scattering from the ship target and oceanic clutters demonstrate the functional dependencies upon the situation of radar surveillance such as the incidence and observation angles, radar altitude, ship RCS and other oceanic conditions.
文摘基于MLAT多点定位的A-SMGCS系统可显著提高机场场面监视的精度。对机场场面监视雷达中数据采集系统的设计方法进行详细地阐述。利用高速A/D实时采集对数放大器输出的回波数据,经F P G A处理后,通过光纤发送至信号处理。实际工作结果表明,该设计方案成熟、可靠,为类似的系统或项目提供一个有益的借鉴。
