Polarization Effects on Direction Finding.

摘要

The results of an investigation of techniques to minimize or correct polarization errors in Direction Finding (DF) Systems are presented. Four techniques are considered. These are Flagging,Switching,Tracking,and Polarimeter. The flagging technique senses situations when the polarization error could be unacceptably large and notifies the DF system of this fact. The switching technique senses the field polarization and chooses the one of two receiving polarizations which is closest. The tracking technique senses the field polarization and adjusts the receiving antenna polarization to match. The polarimeter technique measures the field polarization and computes a correction to the DF output. The residual error after correction by these techniques is analyzed and numerical results for a phase interferometer presented. For the purposes of evaluating these residual errors, a randomly polarized field (in the sense that there is no a priori knowledge of its polarization),is assumed and the cumulative probability distribution of the errors computed. It is shown that all four techniques are capable of reducing the 95% confidence level on the errors to a value consistent with other errors in a very good DF system.