Examination Committee

Prof Raymond S K WONG, SOSC/HKUST (Chairperson)
Prof Ross MURCH, ECE/HKUST (Thesis Supervisor)
Prof Buon Kiong LAU, Department of Electrical and Information Technology, Lund University (External Examiner)
Prof Kevin J CHEN, ECE/HKUST
Prof Howard LUONG, ECE/HKUST
Prof Ho Bun CHAN, PHYS/HKUST

Abstract

Multiple-Input Multiple-Output (MIMO) wireless communication can significantly increase capacity without requiring increases in transmission power or spectrum. MIMO wireless communication has many applications including Wi-Fi (IEEE 802.11n and 802.11ac), long-term evolution (LTE) and massive MIMO. A critical aspect in the design of compact MIMO antennas for communications is providing sufficiently good antenna isolation. The thesis provides a comprehensive design approach, optimization techniques and implementation results for compact MIMO antennas and four new and novel contributions are described.

The first contribution focuses on novel high density MIMO arrays designs. The basic idea of the design is the development of a canonical antenna that can be replicated and concatenated together to form MIMO antennas with arbitrary even numbers of ports. To validate the design, results from 20-port planar printed MIMO antennas are presented operating at 2.6 GHz with a bandwidth of 100 MHz. The second contribution focuses on a port and frequency reconfigurable MIMO slot antenna for WLAN applications. In one configuration, the antenna provides 4-ports operating from 4.9-5.75 GHz and in another configuration, it provides a 2-port antenna operating at 2.4-2.5 GHz together with another 2-port antenna operating at 4.9-5.725 GHz all with isolations greater than 14 dB. Third, we propose a new design for a dual-band multi-port MIMO slot antenna operating in the 2.4/5GHz WLAN. A major advantage of this design over 2nd design is that it does not require reconfiguration. Fourth and finally, we describe a method for designing and optimizing MIMO antenna efficiently using pixelated surface. The proposed antennas are investigated by simulation and measurement.