We claim the ornamental design for a wireless beacon, as shown and described.
FIG. 1 is an isometric view, from the top left, of the wireless beacon.
FIG. 2 is an isometric view, from the bottom right, of the wireless beacon.
FIG. 3 is a plan view from the top of the wireless beacon.
FIG. 4 is a plan view from the bottom of the wireless beacon.
FIG. 5 is an elevation view from the front of the wireless beacon.
FIG. 6 is an elevation view from the back of the wireless beacon.
FIG. 7 is an elevation view from the left side of the wireless beacon
FIG. 8 is an elevation view from the right side of the wireless beacon; and,
FIG. 9 is a plan view from the top of the wireless beacon in a stretched configuration.
The broken line showing of the internal elements of plugs and of hands is included for the purpose of illustrating portions of the “article” and forms no part of the claimed design.