Multi-band circularly polarized series fed array antenna with improved directivity for GNSS and 5G communication

Abstract

This paper presents a series-fed 2 × 4 antenna array operating at multiple bands, namely, GNSS (Global Navigation Satellite System) L1 and L2 bands, NavIC (Navigation with Indian Constellation) S band, and 5G n78 band. The novel series-fed antenna is designed with non-symmetrical radiating elements connected in series to exhibit multi-band characteristics. Rhombic and rectangular slots are etched to improve the bandwidth of the 5G operating frequency and to obtain the desired polarization in the GNSS/NavIC band. A parametric study has been carried out to optimize the essential factors, namely, the distance between antenna elements, the advancement of phase, and the alignment of impedance, that reduce the side lobe level. At L1 band (1575.42 MHz) and L2 band (1.227 GHz), the reflection coefficient value is −26.39 dB and −21.628 dB, respectively. At the 5G band (3.6 GHz), the reflection coefficient is −23.56 dB. At S band (NAVIC), the reflection coefficient is −16.299 dB, with right-hand circular polarization and an axial ratio of 2.89. The antenna displays a minimum angular width of 35.4° with a reduced side-lobe level through the proposed novel series-fed array.