You need the same functionality as the rubber modifier in MegaFiers provides, it adds secondary motion to objects for an antenna you would paint some stiffness into the vertex colours of the antenna in your 3d package and then use the modifier or find a system that does the same or code it yourself
Well the thing about secondary motion is it is driven by the movement of the object but in the system above you can have its motion driven by another object so you would just select a dummy object and have that move with some noise or something and that would cause the antenna to wobble.