文章以77GHz车载毫米波前雷达作为传感器,设计、开发、验证了前方碰撞预警(FCW)功能。毫米波雷达通过发射调频连续波信号来探测目标物的距离、速度、方位角度等信息。前向碰撞预警功能以亳米波雷达感知目标信息和车身状态为输人,以安全...文章以77GHz车载毫米波前雷达作为传感器,设计、开发、验证了前方碰撞预警(FCW)功能。毫米波雷达通过发射调频连续波信号来探测目标物的距离、速度、方位角度等信息。前向碰撞预警功能以亳米波雷达感知目标信息和车身状态为输人,以安全距离模型和预碰撞时间(time to collision,TTC)模型作为预警控制策略。为了保证弯道工况的预警准确率,该系统能在估计自车转弯半径后对于横向距离进行补偿,以剔除相邻车道容易引|起误报的目标。根据智能汽车集成系统试验区(i-VISTA)定义的标准测试场景为测试用例,经过仿真测试得出功能性能均符合法规要求。基于南京楚航科技已量产的77GHz前向毫米波雷达软硬件平台,进行了该功能的实车测试。测试表明,在直道和弯道城市道路工况下,预警控制策略均可以及时触发报警,并且在弯道横向距离补偿后有效避免了相邻车道车辆误触发,整体性能符合期望指标。展开更多
An intelligent liquid classification system based on 77 GHz millimeter wave radar and convolution neural network are proposed in this paper.The data are collected by the AWR1843 radar platform and processed by the neu...An intelligent liquid classification system based on 77 GHz millimeter wave radar and convolution neural network are proposed in this paper.The data are collected by the AWR1843 radar platform and processed by the neural network on the host PC in real-time.The doppler heatmap generated by radar signal processing is tried for the first time as the input of the system.The information carried by the heatmap in 2 dimensions is analyzed and the reason why the doppler heatmap could be used for classification is explained.The feasible experiment proved that the proposed method can successfully classify 8 kinds of common liquid with high accuracy.The result of the experiment is explained and the limitations of the experiment are discussed.It can be drawn that the combination of FMCW millimeter wave radar and convolution neural network is a method with great potential for liquid classification.The advantages of real time,non-invasive and unilateral measurement can also be used for the detection of dangerous liquids.展开更多
The performance of the power amplifier determines the detection capability of 77 GHz automotive radar, and the bias circuit is one of the most important parts of a silicon-germanium power amplifier. In this paper,we d...The performance of the power amplifier determines the detection capability of 77 GHz automotive radar, and the bias circuit is one of the most important parts of a silicon-germanium power amplifier. In this paper,we discussed and designed an on-chip bias circuit based on a silicon-germanium heterojunction bipolar transistor,which is used for the W-band silicon-germanium power amplifier. Considering the low breakdown voltage and the correlation between characteristic frequency and bias current density of the silicon-germanium heterojunction bipolar transistor, the bias circuit is designed to improve the breakdown voltage of the power amplifier and meet the W band characteristic frequency at the same time. The simulation results show that the designed bias circuit can make the amplifier operate normally from-40 to 125 ℃. In addition, the output power and smooth controllability of the power amplifier can be adjusted by controlling the bias circuit.展开更多
文摘文章以77GHz车载毫米波前雷达作为传感器,设计、开发、验证了前方碰撞预警(FCW)功能。毫米波雷达通过发射调频连续波信号来探测目标物的距离、速度、方位角度等信息。前向碰撞预警功能以亳米波雷达感知目标信息和车身状态为输人,以安全距离模型和预碰撞时间(time to collision,TTC)模型作为预警控制策略。为了保证弯道工况的预警准确率,该系统能在估计自车转弯半径后对于横向距离进行补偿,以剔除相邻车道容易引|起误报的目标。根据智能汽车集成系统试验区(i-VISTA)定义的标准测试场景为测试用例,经过仿真测试得出功能性能均符合法规要求。基于南京楚航科技已量产的77GHz前向毫米波雷达软硬件平台,进行了该功能的实车测试。测试表明,在直道和弯道城市道路工况下,预警控制策略均可以及时触发报警,并且在弯道横向距离补偿后有效避免了相邻车道车辆误触发,整体性能符合期望指标。
基金supported in part by the Key R&D program of Shaanxi Province(2020ZDXM5-01)in part by the Fundamental Research Funds for the Central Universities.The review of this article was coordinated by Prof.Long Li.
文摘An intelligent liquid classification system based on 77 GHz millimeter wave radar and convolution neural network are proposed in this paper.The data are collected by the AWR1843 radar platform and processed by the neural network on the host PC in real-time.The doppler heatmap generated by radar signal processing is tried for the first time as the input of the system.The information carried by the heatmap in 2 dimensions is analyzed and the reason why the doppler heatmap could be used for classification is explained.The feasible experiment proved that the proposed method can successfully classify 8 kinds of common liquid with high accuracy.The result of the experiment is explained and the limitations of the experiment are discussed.It can be drawn that the combination of FMCW millimeter wave radar and convolution neural network is a method with great potential for liquid classification.The advantages of real time,non-invasive and unilateral measurement can also be used for the detection of dangerous liquids.
文摘The performance of the power amplifier determines the detection capability of 77 GHz automotive radar, and the bias circuit is one of the most important parts of a silicon-germanium power amplifier. In this paper,we discussed and designed an on-chip bias circuit based on a silicon-germanium heterojunction bipolar transistor,which is used for the W-band silicon-germanium power amplifier. Considering the low breakdown voltage and the correlation between characteristic frequency and bias current density of the silicon-germanium heterojunction bipolar transistor, the bias circuit is designed to improve the breakdown voltage of the power amplifier and meet the W band characteristic frequency at the same time. The simulation results show that the designed bias circuit can make the amplifier operate normally from-40 to 125 ℃. In addition, the output power and smooth controllability of the power amplifier can be adjusted by controlling the bias circuit.
