Measured Characteristics of Dual Depth Dual Frequency Choke Ring for Multipath Rejection in GPS Receivers

Abstract

Dual frequency choke ring design for GPS receivers was introduced in the paper “The First Dual-Depth Dual-Frequency Choke Ring”. This design was intended to provide optimal multipath rejection for both L1 and L2 band, while ordinary choke ring designs have resonant characteristics and provide optimal multipath rejection only in L2 band. This work represents a pilot design of dual-depth dual-frequency choke ring developed by authors. Measured results are shown in comparison with characteristics of ordinary single frequency choke ring. It has been shown that for developed design improvement of multipath rejection in L1 band is about 10 dB, while characteristics in L2 band are the same as for ordinary single frequency choke ring designs.