Antenna system with reduced multipath reception

摘要

An antenna system with a sharp difference in directional pattern is intended for receiving GNSS signals. The antenna system includes at least two antenna elements located above a high-impedance capacitive ground plane, and a combining network. Antenna elements are spaced apart in vertical direction. The combining network provides subtraction of the signal reflected from the ground, the arrangement of antenna elements above the high-impedance capacitive ground plane making such subtraction efficient.

主权项

1. An antenna system for operating with circularly-polarized signals, the antenna system having a vertical axis relative to which amplitude directional pattern is symmetrical and a plane perpendicular to the vertical axis such that the antenna system has a right-hand circular polarization upward from the perpendicular plane, the antenna system comprising:
a high impedance capacitive ground plane (HICGP); first and second antenna elements; and a combining network connected to the first and second antenna elements; wherein the first and second antenna elements are located above the HICGP and are separated along the vertical axis by a gap; and wherein the combining network subtracts signals received by the first element from signals received by the second element to produce an output signal representing the circularly-polarized signals received only from an upper hemisphere.