Abstract: The installation space and weight are taken as constraints of the airborne antenna. Omni-directional antenna is a useful method to transit the signals for short range communication, it is necessary to design an antenna with low weight and small size. Different with the knife-edge monopole antennas, this paper present an double arm microstrip monopole antenna. The antenna has a low profile of 2 mm, which can be used as conformal antennas. Besides this antenna provides a wide VSWR band over 50%. The measured results show the validity of the design based on simulation.