Error Performances of 64-ary Triangular Quadrature Amplitude Modulation in AWGN Channel

It is well known that the square quadrature amplitude modulation (QAM) has been widely used as a modulation technique for digital communication systems due to its simple detection in spite that the power efficiency of the square QAM is not optimum. The newly proposed 16-ary triangular QAM provides considerable power gain while keeping low detection complexity. In this paper, we propose two 64-ary signal constellations with triangular structure and suggest their detection methods. We also consider bit stream mapping method to obtain the bit error rates of proposed modulations. Theoretically, the two signal constellations provide power gains of 0.55 dB and 0.76 dB over the square QAM, respectively.