Design and Analysis of LTE MIMO Handset Antenna with Enhanced Isolation using Decoupling Technique

In the future, wireless communications require higher data rate for various mobile services. One of the most noticeable techniques for the next generation wireless communication is LongTerm Evolution (LTE) not only at 700MHz band but also at other various bands. Multiple-inputmultiple-output (MIMO) system is essential for this technique. MIMO systems use multiple antennas at transmitter and receiver to enhance the performance of wireless communications: the channel capacity. However, in order to design MIMO systems for mobile handsets that have limited spaces, isolation between antennas positioned closely to each other should be considered because the poor isolation means degradation of the performance of MIMO systems. Various methods have been found to enhance isolation [1-3]. Among those three methods, decoupling technique from [2] has many advantages. The parameters composing the decoupling network can be easily calculated from measured scattering parameters, and they are also adoptable for any antenna structures. In this paper, we have presented the comparison of the two MIMO antennas for LTE applications in 700MHz band, with and without decoupling network. For the performance evaluation of the proposed MIMO antennas, relationship between the isolation and channel capacity was investigated.