干涉仪作为机载电子侦察设备常用的一种测向体制,有着测向精度高、速度快、频率覆盖范围广等特点。在梳理干涉仪测向原理的基础上,明确了干涉仪天线单元极化特性的不一致是干涉仪测向误差的一个重要来源。针对这一问题给出了一种基于双极化天线的DOA(Direction Of Arrival)和极化信息联合估计方法,该方法在获取各天线单元水平和垂直极化方向的幅度和相位信息的基础上,通过通道间数据的对比分析和全局寻优的方式获取辐射源信号的DOA和极化参数。仿真表明该方法能够将极化特性不一致导致的相位误差降到最低,从而有效避免天线单元极化特性不一致对机载电子侦察设备测向精度的影响。
Smart material and structure (SMS) is a challenging novel technique for the 21 century especially in fields of aviation and aerospace. Vibration and noise suppression smart structure is an important branch of SMS. There are several typical structures such as the cabin of an airplane, space station, the solar board of satellite and the rotor blade of a helicopter, of which the vibrations and radiation noises have bad influences on precise equipments and aiming systems. In order to suppress vibrations and noises of these structures, several algorithms are applied to the models which simulate the structures. Experiments are performed to suppress vibrations and noises by bonding sensors and actuators to the structures at the optimized locations and using computer based measurement and control systems. For the blade vibration control of a helicopter, a non contact method of signal transmission by magneto electric coupling is discussed. The experimental results demonstrate that the methods used for active control are effective.
