Reduction of Envelope Correlation on non-metallic and metallic chassis phones

Two antennas, main and sub, are used for reception in Long Term Evolution (LTE) terminals nowadays. In order to have a good MIMO performance, low coupling loss and low correlation between antennas are considered. Currently, main antenna usually situates at the bottom of the phone because of Specific Absorption Rate (SAR) requirement, whereas sub antenna locates at the top of the phone providing better spatial diversity. In this paper, feasible implementations of scatterers on both non-metallic and metallic chassis phones are provided. Experimental results show that the Envelope Correlation Coefficients (ECC) can be reduced from 0.7 to 0.2 at 750 MHz after inserting scatterers. Dual-frequency operations are also possible if two scatterers are introduced on different sides of a phone chassis.