| dc.description.abstract | In the thesis, we propose an integrated architecture of wideband, time division duplex (TDD), multiple input-smart antenna output (MIS*O), and multitone-code division multiple access (MT-CDMA) transceiver, which is advantageous characteristics of frequency, time, spatial domain. We consider multiuser and multiple access interference (MAI) scenarios in downlink communication and combat MAI of other users by generalized sidelobe canceller (GSC) and minimum variance distortionless response (MVDR) beamforming techniques. Firstly, in our proposed system architecture, transmission signals are generated simultaneously in frequency and spatial domains to reach high speed downlink capability through parallel data transmission. Secondly, due to the availability of channel gains by means of uplink receiving in a TDD system, it is therefore applied in the downlink transmission signals to proceed spatial-frequency channel preprocessing. Hereafter, in order to increase system capacity and speed, we take advantage of multiple spread spectrum code generators, and transmit multiple channel preprocessed signals simultaneously. Then, the goal of wideband, multi-carrier, parallel transmission of high speed of data is reached by means of inverse fast Fourier transform and guard band intervals. Finally, the diversity gain in spatial domain is obtained in subscriber through simultaneous multi-antenna transmission signals. After through the transmission processing as aforementioned, in the subscriber side, we can also utilize a smart antenna with many antenna elements spaced within half wavelength, different from conventional single antenna, to receive transmitting signals from base station to enhance anti-jamming capability in specific directions. | en_US |