Performance Analysis of Joint Adaptive Modulation and Diversity Combining in TDD-CDMA Systems
نویسندگان
چکیده
Adaptive modulation and diversity combining represents the enabling techniques for the future generation of wireless communication. Adaptive modulation is a transmission scheme in digital communications where the transmitter adapts its transmission mode in accordance with the channel. In TDD systems the channel state is known in the transmitter side because of channel reciprocity, hence the adaptive modulation and diversity combining techniques are implemented in TDD-CDMA systems. The combination of TDD and CDMA allows for efficient bandwidth utilization, primarily through uplink/downlink asymmetry and frequency re-use respectively. Both adaptive modulation and diversity combining concepts use some predetermined threshold in their operation. Based on this observation, we naturally combine these two concepts, and develop and analyze Joint Adaptive Modulation and Diversity Combining schemes. The scheme of AMDC (Joint Adaptive Modulation and Diversity combining) is 1.Power efficient AMDC scheme is performed and analyzed in terms of power efficiency and error rate performance in TDD-CDMA systems.
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