A dual band dual circularly polarized symmetric array antenna component is proposed to address the issue of independent receiving and transmitting antennas in traditional TT&C fields. A symmetrical array antenna is adopted to achieve dual band operation characteristics, while a 3 dB bridge is used to realize dual circularly polarized radiation characteristics, and a duplexer is stacked below the antenna to achieve high isolation between the receiving and transmitting frequency bands. Based on this design concept, an antenna prototype is manufactured and tested based on the simulation analysis. The results show that the designed antenna can operate in frequency bands covering 1.75～1.85 GHz and 2.2～2.4 GHz, and the axial ratio within these bands is less than 3 dB. The suppression between the receiving channel and the transmitting channel reaches over 70 dB. This provides a feasible design scheme for the shared antenna unit for transmitting and receiving in practical engineering.