Communication systems engineering
Communication systems engineering
Bit loading with BER-constraint for multicarrier systems
IEEE Transactions on Wireless Communications
Hi-index | 0.00 |
Orthogonal Frequency Division Multiplexing (OFDM) has been thoroughly investigated as an enabling technology for future broadband multimedia communication. In this paper, we suggest adaptive bit allocation algorithms that operate in a frequency selective fading channel environment by exploiting channel state information obtained through a feedback channel. The proposed algorithms try to maximize the overall throughput of the system with significantly reduced complexity while guaranteeing that mean bit error rate (BER) of all sub-channels remains below the pre-defined BER threshold. To do that, the first proposed algorithm divides all sub-channels into several groups according to their signal-to-noise ratio (SNR). The grouping criteria are adaptive to the current channel state and BER constraint. The second algorithm tries to find the appropriate constellation size for each sub-channel. The proposed algorithms were compared with existing algorithms through simulation. The simulation results show that the proposed algorithms are close to optimum solution with significantly lower complexity.