Abstract
For the increasing demand for high-rate indoor wireless communications, 60 GHz frequency bands have attracted much attention. The advantages of 60 GHz bands include high data rates and wide unlicensed bandwidth which is available worldwide. However, small wavelength of 60 GHz bands causes high path loss. To mitigate the path loss and increase the system capacity, the multibeam beam-forming orthogonal frequency-division multiplexing (OFDM) technique can be applied. In the thesis, multibeam beam-forming OFDM systems in 60 GHz bands are considered. The IEEE 802.15.3c channel model which describes the statistical behavior of 60 GHz channels in temporal and spatial domains is employed. One of our contributions is to characterize the effect of random multipaths in 60 GHz systems by exact mathematical analysis. Based on the analysis, some multi-stream beam-forming schemes are devised to enhance the system capacity. Precise system analysis is verified by numerical simulations. Finally, performance of different beam-forming schemes are discussed and compared.