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A Novel Blind SNR Estimation Algorithm for SC-IFDM Ionospheric Scatter Systems

The ionospheric scatter communication system is challenging due to its large transmission loss and usually works under low signal to noise ratio (SNR). A novel blind SNR estimation algorithm for single carrier interleaved frequency division multiplexing (SC-IFDM) system is proposed to improve the accuracy of the estimation. The received time domain data are used to estimate the signal power and noise variance based on the order moment algorithm. The SNR of each SC-IFDM symbol as well as its average SNR over a whole sub-frame can be estimated. Simulation results show that the proposed algorithm outperforms existing estimators at the low SNR region, and that the credible range can be extended to approximately -18dB. Besides, the algorithm is non-pilot aided, making it appealing to wireless systems for saving overhead.