Abstract: Circularly polarized (CP) antenna is wide used in satellite communication and orientations. As the development ofsatellite system, CP antennas of low profile and wide beam are more and more interest. In this paper, A practical and novel CPantenna with broad beam is presented, which uses double arm helix as radiated body. The proposed antenna achieves the widebeam above 160°, and operates well impedance matching and CP performance. The presented antenna can be applied to warpand civil communication domain.