A Novel Surface Treatment Method for Improving the Antenna System Performance of Mobile Phones with Stainless Steel Frame

A novel surface treatment method of plating Cu+PPS film/coating on a mobile phone's stainless steel frame for improving the antenna system efficiencies is proposed. The mobile phone was measured in free space, in a silicon cover, and in the hand and cover simultaneously. It's found that with this surface treatment, the total efficiency of the antenna system can be improved in all the four cases respectively by 14.22%, 1.38%, 15.19% and 1.72% at 940MHz (GSM900:880-960MHz), 2.59%, 3.21%, 4.81% and 1.43% at 1720MHz (DCS:1710-1880MHz) and 6.34%, 2.85%, 9.83% and 2.32% at 2100MHz (WCDMA:1920-2170MHz). This lowcost surface treatment method is an important breakthrough to improve antenna system performance of mobile phones especially for those with a stainless steel frame, and suitable for mass production.