Complex number RS coded OFDM with systematic noise in the guard interval

Recently we presented a novel OFDM (orthogonal frequency division multiplexing) signaling concept, where the cyclic prefixes (CPs) are replaced by deterministic sequences which we call unique words (UWs). The UWs are generated by appropriately loading so-called redundant subcarriers. By that a complex number Reed Solomon (RS) code construction is introduced which can advantageously be exploited in an LMMSE (linear minimum mean square error) receiver. The overall concept clearly outperforms CP-OFDM in frequency selective channels. In this paper we introduce a method that significantly reduces the energy of the redundant subcarrier symbols by allowing some systematic noise in the UWs. The concept features a notable performance and bandwidth efficiency gain compared to our original UW-OFDM approach.