移动卫星通信终端天线极化跟踪研究

针对移动通信终端天线的极化失配损失问题,利用两个正交线极化天线结合相应的馈电网络实现了任意方向的线极化波,用于移动状态下的天线极化跟踪。提出了通过控制两个正交线极化天线的相位差来接收任意线极化波的方法,并给出了相位差与极化角的关系。当两个正交线极化天线增益及其对应通道间的幅度和相位均相同时,接收到的信号强度随相位差的变化而作余弦,且当相位差ψ为2θ-π2时,信号强度有最大值。基于该方法进行理论仿真,并得到了极化跟踪曲线,与测试结果相比,吻合良好。将该方法应用到卫星通信移动终端,在运动过程中信号稳定,未出现明显极化失配现象,验证了该算法的有效性。

Study of the Polarization Tracking for the Antenna of Mobile Satellite Terminal

Any linear-polarized wave which can be applied to polarization tracking for the moving antenna is obtained with two perpendicular linear-polarized antennas and corresponding feed netrork.A new method of the receiving any linear-polarized wave by adjusting the phase difference between two perpendicular linear-polarized antennas is put forward.What the phase difference between two perpendicular linear-polarized antennas change with polarization angle is deducted.When the gains of two perpendicular linear-polarized antennas and the amplitude and phase of their channels are equal all,the receiving signal strength changing with the phase difference between two perpendicular linear-polarized antennas is satisfy cosine curve,and when ψ=2θ-π 2,it is maximum.The polarization tracking curve computed by the proposed method agrees well with the measured results.The signal is steady since the method is applied to polarization tracking for the moving Mobile Satellite Terminal,and polarization mismatch is not occurred,which demonstrated the effectiveness of the method.Which demonstrated the effectiveness of the method.