Compact dual-band antenna for wearable computer system

In this paper, a compact antenna operated at 2.45 GHz (for long range communication) and 5.8 GHz (for short range communication) with the patch size of 22×16 mm is presented. In both simulated and tested results, the desired broadside pattern, and also the bandwidth of 100 MHz (4%) for 2.45 GHz and of 200 MHz (3.5%) for 5.8 GHz are performed. Those bandwidths are large enough to meet the requirements of wearable computer system. The antenna gain is measured as about 0.5 dBi and 1.5 dBi for the lower and higher resonant frequency, respectively. The resonant frequency are both slightly shift down when the antenna is placed near human body.