Antenna Solutions for 4G Smartphones in Laser Direct Structuring Technology

Two antenna designs operating in the LTE/4G cellular frequency bands are proposed in this paper. Both designs consist of a driven strip which capacitively excites a parasitic grounded strip for a better matching response around 700 MHz. The antennas are realized using Laser Direct Structuring (LDS) technology on POCAN plastic material with a height of 5 mm above the system Printed Circuit Board. Passive matching circuits are necessary at each antenna’s feed, to match the input impedance to 50 Ohm at the desired operating bands (700–960 MHz and 1.7–2.2 GHz for the first design and 700–960 MHz and 1.7–2.7 GHz for the second). The simulation results are validated through s-parameter and total efficiency measurements. To form a basis for future studies, the effect of the hand and the head of the user are investigated upon the antenna performance.