Vulnerability to radio interference and multipath is a well-known drawback of satellite-based navigation systems. This is widely accepted as a critical issue for safety-of-life applications such as precision approach operations in aviation. Interference and multipath signals enter the navigation receiver through the antenna which, in order to minimise such signals, can be used as a spatial- and frequency-domain filter provided that some critical antenna parameters are controlled. The most important parameters are the shape of the antenna pattern with associated cross-polar levels and polarisation purity as well as an appropriate in and out-of-band frequency response. This paper aims at giving an overview of existing and future antenna technologies to be used with satellite navigation receivers. Also, we will consider some auxiliary technologies like resistive or high impedance
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