Antenna designs and propagation models for advanced wireless communications systems

To help enable the next generation of the wireless technology, paradigm shifts in the antenna designs are needed, and significant advances in the development of computationally efficient and physics-based propagation models for channel characterization are required. In the antenna design area, high-performance and low-cost antenna array designs with full 2D steering capabilities can play a significant role in increasing the capacity, extending the range, and in improving the capabilities and quality of service in a wireless communications system. A wide variety of space diversity techniques has been proposed and the development of a low-cost adaptive antenna array is crucial in the realization and implementation of these systems. In this presentation, the design and optimization of a new low-cost phased array antenna based on the CTS technology is described. The new CTS array provides full 2D scanning capabilities using ferroelectric (BSTO) material. The design procedure is described and techniques for overcoming the significant conductor losses discussed. Two computationally efficient techniques for modeling indoor/outdoor propagation environments are described and a procedure for improving the accuracy of the ray tracing-based calculations using a multigrid FDTD method are discussed.