Abstract: A dual-band antenna includes a multi-layer substrate and metal strips formed on different layers of the multi-layer substrate. The multi-layer substrate includes at least a first substrate and a second substrate. The metal strips include a first metal strip, a second metal strip, and a sleeve structure. The first metal strip formed on the first substrate further includes a first feeding end and a first open circuit end. The second metal strip formed on the second substrate further including a second feeding end, a vortical metal structure and a second open circuit end, wherein the second feeding end connects the first metal strip through a first conductive via. The sleeve structure formed on the multi-layer substrate by skirting the first metal strip is electrically isolated.

Abstract: A dual-band antenna includes a multi-layer substrate and metal strips formed on different layers of the multi-layer substrate. The multi-layer substrate includes at least a first substrate and a second substrate. The metal strips include a first metal strip, a second metal strip, and a sleeve structure. The first metal strip formed on the first substrate further includes a first feeding end and a first open circuit end. The second metal strip formed on the second substrate further including a second feeding end, a vortical metal structure and a second open circuit end, wherein the second feeding end connects the first metal strip through a first conductive via. The sleeve structure formed on the multi-layer substrate by skirting the first metal strip is electrically isolated.