Geometrical theory, modeling and applications of channel polarization

Abstract

Long-term evolution (LTE) standard has been successfully stabilized, and launched in several areas. However, the required channel capacity is expected to increase significantly as the explosively increasing number of smart-phone users implies. Hence, this is already the time for leading researchers to concentrate on a new multiple access scheme in wireless communications to satisfy the channel capacity that those smart users will want in the not-too-distant future. The diversity and multiplexing in a new domain - polarization domain - can be a strong candidate for the solution to that problem in future wireless communication systems. This research contributes largely to the comprehensive understanding of polarized wireless channels and a new multiple access scheme in the polarization domain - polarization division multiple access (PDMA). The thesis consists of three streams: 1) a novel geometrical theory and models for fixed-to-mobile (F2M) and mobile-to-mobile (M2M) polarized wireless channels; 2) a new wireless body area network (BAN) polarized channel modeling; and 3) a novel PDMA scheme. The proposed geometrical theory and models reveal the origin and mechanism of channel depolarization with excellent agreement with empirical data in terms of cross-polarization discrimination (XPD), which is the principal measure of channel depolarization. Further, a novel PDMA scheme utilizing polarization-filtering detection and collaborative transmitter-receiver-polarization (Tx-Rx-polarization) adjustment, is designed considering cellular orthogonal frequency division multiplexing (OFDM) systems. The novel PDMA scheme has large potential to be utilized with the conventional time, frequency, and code division multiple access (TDMA, FDMA, and CDMA); and spatial multiplexing for next-generation wireless communication systems.