Antenna

FIG. 1 is a front perspective view of an antenna showing our new and ornamental design;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a rear view thereof;

FIG. 5 is a left-side view thereof;

FIG. 6 is a right-side view thereof;

FIG. 7 is a top view thereof;

FIG. 8 is a bottom view thereof; and,

FIG. 9 is an enlarged partial view of the area circumscribed by dot-dash broken line in FIG. 1 .

The dash-dot broken lines in the drawings illustrate the bounds of the portions shown enlarged in the drawings, and form no part of the claimed design.