Nine-band planar printed antenna for mobile handsets

A nine-band planar printed antenna with a compact size of 20 mm×28 mm×0.8 mm for mobile handsets is proposed. A meandering monopole, a parasitic ground branch and a coupling branch are adopted to generate five resonant modes, and the impedance matching is improved by introducing three tuning pads and a step-shaped transition structure near the feeding point for all the resonance modes, resulting in enhanced operating bands of the proposed antenna. By analyzing the effects of the crucial parameters of the proposed antenna on the bandwidth, the crucial parameters are optimized and the desired performance is obtained. The measured -6 dB impedance bandwidth of the antenna prototype ranges from 700 to 1 008 MHz and from 1 692 to 2 984 MHz, covering the LTE700/2300/2500, GSM850/900, DCS/PCS/UMTS and 2.4-GHz WLAN bands. Good radiation performances are achieved over the operating bands.