A low-complexity 2D signal space diversity solution for future broadcasting systems

DVB-T2 was the first industrial standard deploying rotated and cyclic Q delayed (RCQD) modulation to improve performance over fading channels. This enables important gains compared to conventional quadrature amplitude modulations (QAM) under severe channel conditions. However, the corresponding demodulation complexity still prevents its use for wider applications. This paper proposes several rotation angles for different QAM constellations and a corresponding low-complexity detection method. Results show that the proposed solution simplifies both the transmitter and the receiver with often better performance than the proposed angles in DVB-T2. Compared with the lowest complexity demappers currently used in DVB-T2, the proposed solution achieves an additional reduction by more than 60%.