Combination of spectral and SVD precodings for out-of-band leakage suppression

Since the out-of-band (OOB) power suppression of Orthogonal Frequency Division Multiplexing (OFDM) has been an essential topic for various wireless communication applications such as Cognitive Radio (CR) systems, in this paper, two existing precoding techniques are investigated. Then a combined approach which properly adjusts the matched code rates of these two investigated techniques is proposed. Numerical results show that, for OFDM without guard intervals (NG-OFDM) and with zero padding (ZP-OFDM), the proposed method gives significant further improvement on OOB power suppression and almost no extra drawback than either of the two original techniques.