The ornamental design for a broadbandhornantenna, as shown and described.
FIG. 1 is a perspective view of a broadband horn antenna design showing the new design.
FIG. 2 is another perspective view of a broadband horn antenna.
FIG. 3 is a front view of a broadband horn antenna.
FIG. 4 is a rear view of a broadband horn antenna.
FIG. 5 is a right side view of a broadband horn antenna.
FIG. 6 is a left side view of a broadband horn antenna.
FIG. 7 is a top view of a broadband horn antenna; and,
FIG. 8 is a bottom view of a broadband horn antenna.
Any shading and cross-hatching are not features of the design but are utilized to illustrate the surface contours of the broadband horn antenna design in the drawings.
The broken lines depict portions of the broadband horn antenna that form no part of the claimed design.