An Adaptive Multiple Antenna Transmission Scheme for an OFDMA System
نویسندگان
چکیده
We propose an orthogonal frequency division multiplexing frequency division multiple access (OFDMA) system with an adaptive multiple antenna transmission scheme for future wireless communkatlon systems. In the system, both a transmit diversity scheme with high order modulation and a spatial multiplexingscheme with low order modulation are employed for the given spectral efilciency, between which, the proper transmission scheme is selected according to the channel state. It b observed that the proposed system with a selection algorithm based on the post processing SNR reduce the average transmit power. Keywords-Spatial Multiplexing, Transmit Diversity, OFDMA
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تاریخ انتشار 2004