An Efficient Blind Modulation Detection Algorithm for Adaptive OFDM Systems

Adaptive modulation is a method to increase the data capacity, throughput and efficiency of time division du- plexed wireless communication systems. In adaptive modulation, the transmitter continually monitors the dynamic channel and adjusts the transmission parameters such as modulation order, coding rate etc. accordingly. Blind modulation detection schemes play an important role in adaptive systems to eliminate the need for transmitting modulation information, thereby increasing spectral efficiency. In this paper, an improved statistical blind modulation detection method based on the Kullback-Leibler distance is proposed for OFDM based wireless communication systems. Simulation results show that this blind modulation detection algorithm outperforms similar previously proposed algorithms.

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