为研究无人机信道特性,针对地面控制站(GCS)环境特点和非全向多天线系统,建立并分析了基于散射体三维几何分布的单跳同心圆筒散射(GBSBCCS)宽带传播模型,根据方位角非全向散射和俯仰角非对称分布的特性,结合无人机实际飞行参数特点,推导出简洁的空时频联合相关函数。通过仿真进行了验证,并对相关特性影响因素进行分析,结果表明地面控制站采用非全向天线时,信道的空时频相关尺度将会增大,而无人机采用非全向天线不会影响其相关性。
In order to analyze channel characteristic of the unmanned aerial vehicles, according to the surrounding traits around the ground control station (GCS) and the non-omnidirectional multiple antennas system, the paper has presented and analyzed a three-dimensional geometrically-based single-bounce concentric-cylinders scattering (GBSBCCS) wideband channel model. According to the characteristic of non-isotropic scattering for the azimuth angle and asymmetrical distribution for the elevation angle, the terse joint space-time-frequency cross-correlation function is derived from the flying parameters in practice. The simplified validity and the factors of the correlation are analyzed in the simulation, and results show that the correlation scale of the space-time-frequency will be enlarged while the non-omnidirectional antennas are employed in the GCS, but the non-omnidirectional antennas used in the aircraft do not affect the correlation scale.
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