Design of multiband planar antenna for mobile devices

In this paper, three designs of planar antenna is presented. These low profile planar antennas can be used within widely used bands of frequencies that is, between 800MHz to 9GHz (10 bands) of all cellular from 2G to 4G and beyond. In addition, the coverage frequency includes wireless local area networks (WLAN) and WiMax. Significant structural changes are made in one of the latest structure of multiband antenna which is a combination of L-type, C-type and inverted F-type. All of the bands showed the gain of over 2dB and significant S11 parameters of below −10dBm. Additionally, all of them have significant 3-dB bandwidth. The changes in structure further improved bandwidth, gain for some of the bands. With coupled-fed mechanism and a slotted ground structure, we obtain multiband and wideband characteristics. The influences of the modifications introduced into the ground plane as well as structure of all types of antenna, improved the bandwidths significantly. The design structure is presented, simulated results of radiation pattern, the gains, S11 parameters and results are discussed. The obtained results can meet the requirements of practical mobile phones.