The Design And Research Of Compact UWB-MIMO Antenna

Wireless communication system with broadband, high communication quality and miniaturization characteristics has become a crucial development direction of the future. As one of the key components of mobile communication devices, MIMO(Multiple-Input Multiple-Output) antennas with compact size and ultra wide band(UWB) have been attached great importance in researches on them. Based on this background, UWB antennas and MIMO antennas are deeply researched in this dissertation, and a compact UWB-MIMO antenna is proposed using microstrip antenna miniaturization technology; then, a new structure which combines the asymmetric coplanar strip(ACS)fed with shared radiator are proposed and studied. Thoroughly simulation analyses are conducted on this new structure. Two compact ACS-fed UWB-MIMO antenna with applying this new structure are successfully designed. Other means such as orthogonal polarization feed, defected ground, stub of the ground etc. are also employed to increase the antenna’s isolation. With the results of simulation, optimization and experimental test, the new structure shows its values in the design of compact UWB-MIMO antennas.Major works conducted in this dissertation are summarized as follows:1. The theory and technical indicators of the MIMO antennas are analyzed. Based on the miniaturization technology of microstrip antennas, further research on compact UWB-MIMO antennas are made;2. To solve the compact UWB-MIMO antenna problem in the mobile communication devices, the ACS-fed with shared radiator structure is proposed and researched. The specific role of different slots in the new structure are studied when it is used in a UWB-MIMO antenna, then the antenna is tested and validated;3. The new structure is applied in the design of a compact 4-port UWB-MIMO antenna, and the antenna is simulated, tested and validated.The works carried out in this dissertation show that the new proposed UWB-MIMO antennas have advantages such as easy to be machined, small size and wide broadband, and fit miniaturization and ultra wideband requirements of wireless communications devices. The works conducted in this dissertation has reference values for engineering applications.