This paper proposes a novel stacked tri-band circularly polarized antenna which has three independent ports. To obtain tri-band operation, a stacked three layers of microstrip antenna working at different frequency is presented. Each of them is fed by dual feed probes. The simulated results show that the antenna can cover Compass Navigation Satellite System CNSS B3 1.268 GHz, L band 1.615 GHz and S band 2.49 GHz. The proposed antenna has achieved a bandwidth of 3.1%, 6.8% and 2.3% at each band, respectively. It exhibits small axial ratio under 3dB in three bands for the CNSS applications. Details of the proposed antenna design and results for the obtained tri-band circularly polarized performances are presented and discussed.
