Performance Evaluation Of Non-Uniform Modulation Of Ofdm Subcarrier In The Underwater Acoustic Environment
Partial FFT demodulation is a newly-emerging technique to mitigate the inter-carrier interference (ICI) of orthogonal frequency division multiplexing (OFDM) systems over time-varying underwater acoustic channels. In this letter, we extend the partial FFT demodulation method for a single-input single-output (SISO) configuration to the multiple-input multiple-output (MIMO) case. By assuming no channel knowledge, we design an adaptive algorithm that performs sliding-window channel estimation, partial FFT combining and data detection across subcarriers iteratively. Furthermore, a new parameter? residual ICI span? is introduced to counteract the post-combining ICI and provide a better system performance. Here we are using relay selection over OFDM for underwater acoustic systems. Performance Evaluation Of Non-Uniform Modulation Of Ofdm Subcarrier In The Underwater Acoustic Environment
- Base station to end user transmission
- Due to spectrum scarcity, the user couldn’t be allocated sufficient power over the network to enhance data transmission on time secured in nature
- OFDM has been enabled for the communication in multipath direct LOS communication over the chlorophyll concentrated regions
Underwater Relaying Channel:
- Single-input single-output (SISO)
- PAM,4,16,64 M-Array QPSK,DPSK
- Estimated depth sea interference
- Deployed for higher performance than traditional perfect feedback-based systems.
- MATLAB 10 or above versions
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