自由空间导线天线辐射模式分析

采用分段正弦基矩量法计算线天线电流,借助分段正弦电流辐射场表达式,将各分段电流产生的辐射场进行线性叠加,进而获得天线总的辐射场。该辐射场利用球面波展开法进行展开,同时采用数值积分方法求取辐射场球面波展开式中各模式的系数值。以3种基本单元天线:偶极子天线、圆环天线以及螺旋天线为例,定量分析了3种基本单元天线的辐射模式,验证了这一方法的正确性。

Model analysis on radiation fields of wire antenna in free space

The method of matrix moment adopting piecewise sinusoidal basis functions is used to get the current of wire antenna.With the aid of the radiation field expression of piecewise sinusoidal current,the total radiation field of the antenna is obtained through linear superimposition of contribution fields of every piecewise current.The spherical wave expansion is introduced into antenna radiation modal analysis.In addition,numerical integration is adopted to get the spherical wave coefficients of antenna radiation field.Using the proposed method,the mode coefficients of dipole,circular loop antenna and helical antenna is obtained,which validates the feasibility of the method.