An antenna assembly may include first and second adjacent antenna elements each including a conical antenna body having a base and an apex opposite the base. The antenna assembly may also include a cylindrical antenna body extending from the base of the conical antenna body, and a choke assembly including a choke shaft having a proximal end coupled to the conical antenna body and a distal end opposite the proximal end. The choke assembly may include at least one choke member carried by the distal end of the choke shaft in longitudinally spaced relation from an opposing end of the cylindrical antenna body to define at least one choke slot. Each of the first and second conical antenna bodies may be aligned along a common longitudinal axis with respective apexes in opposing relation to define a symmetrical biconical dipole antenna.