Novel multipath mitigating ground planes for multiband global navigation satellite system antennas

Multipath mitigating ground planes for dual band (L1/L2) global navigation satellite system (GNSS) antennas are proposed. Two novel ground planes; dual band electromagnetic band gap (EBG) ground plane and cross plate reflector ground plane (CPRGP) are presented. The ground planes are designed to improve the antenna backlobe and cross polarization performance at both L1 (1.575 GHz) and L2 (1.227 GHz) bands by suppressing the surface wave propagation. In contrast to the conventional corrugated type choke ring ground plane, the proposed ground planes have smaller thickness. The dual band EBG consumes larger space but still have the advantage of maintaining a low profile and low mass. The CPRGP however has the combined advantage of compact size and performance. The CPRGP ground plane also has low mass, low manufacturing cost and does not require any periodicity. Multipath mitigation performance of both ground planes is compared against the conventional choke ring type corrugated ground plane. Simulation results and multipath rejection ratio (MPR) of the proposed ground planes show that the CPRGP, EBG and choke ring ground planes give similar multipath mitigating performance with CPRGP having an added advantage of compact size.