Trellis-coded CIOD using conjugate symmetric rotated QAM signal set

A trellis-coded coordinate-interleaved orthogonal design (TC-CIOD) for four transmit antennas with a rotated QAM base signal set is introduced. To design a high rate pre-encoder the base signal set is expanded by conjugating the rotated QAM signals without changing the transmit signal set at each transmit antenna. The proposed TC-CIOD provides coding gain without increasing peak-to-average-power ratio.