Patent ID: 6897812

Claim:
A dual-band antenna providing signals for proceeding radio communication at a first frequency and a second frequency, comprising: a multi-layer substrate, which includes at least a first substrate and a second substrate; a first metal strip, which is formed on said first substrate and further includes a first feeding end and a first open circuit end; a second metal strip, which is formed on said second substrate and further includes a second feeding end, a vortical metal structure and a second open circuit end, wherein said second feeding end connects said first metal strip through a first conductive via; and a sleeve structure, which is formed on said multi-layer substrate by skirting said first metal strip for increasing the bandwidth of said second frequency; wherein said first frequency is resonated by the strip between said first feeding end and said second open circuit end, and said second frequency is resonated by the strip between said first feeding end and said first open circuit end.