Mobile Phone Antenna And Multi-Antenna System Design

The mobile industry has experienced a dramatic growth, and the antennas need to meet higher performance requirements. The main challenges of mobile phone antenna design are the requirements of small size and multi-systems in multi-bands. In this paper, firstly, magnetic materials of different parameters are used to miniaturize a dipole antenna. Secondly, we design a miniaturized multi-band mobile antenna. Lastly, dual antenna system, based on the multi-band mobile antenna, with three different distributions are presented and compared. The main content of this paper are as follows:1. Two magnetic materials of different parameters(both have high relative permittivity and their relative permeabilities are greater than 1) are used to miniaturize a dipole antenna. Through the simulation and measurement, and compared to the common foam material dipole, we find the antenna size is much more miniaturized with higher parameter material. However, the antennas have poor far-field radiation performance because of the high loss of the magnetic materials.2. We design a multiband mobile antenna. The antenna can work in 880 MHz to 960 MHz and 1700 MHz to 2700 MHz, and has a small size(33mm×10mm×5mm) compared to the operating wavelength of the antenna. Then we discuss the resonant patterns of three different frequencies and the influence of the chassis size to antenna performance.3. The multi-band antenna is used to form a dual antenna system, and we discuss the isolation and correlation of three different distributions, of which the first situation is the antennas are aligned on the diagonal side of the chassis, second one is on the same long side of the chassis, and the last one is on the same short side. The result shows that these three types all have bad isolation in the low frequency, and the third type has the worst performance because of the close range of two antennas.