Design of MIMO antenna based on an improved neutralization line

Abstract

A Multiple Input Multiple Output(MIMO) mobile phone antenna suitable for mobile terminal is proposed in this paper. The proposed antenna is composed of two center-symmetrical antenna units. In order to expand the bandwidth of the antenna, these two units are fed by coupling mode, and it ensures the miniaturization of the antenna. To obtain a high isolation between the two antenna units, a T-shaped branch is designed on the middle of the ground, and the neutralization line is introduced used to connect two units. The simulation results show that the proposed antenna can cover two important operating frequency bands of 824 MHz～960 MHz and 2 300 MHz～2 600 MHz, and the physical length of the neutralization line is reduced effectively due to the lumped inductance. The proposed antenna was fabricated and tested, and the measurement results were consistent with the simulation results.

Keywords

• MIMO antenna; mobile terminal; neutralization line technique; isolation degree; miniaturization