On the Probability of Error for Triangular Quadrature Amplitude Modulation

We compute the exact value of error probability per symbol (SER) for triangular quadrature amplitude modulation (TQAM) scheme in the case of AWGN channel. The results show that the exact value of SER follows the behavior of the known upper bound [Kostadinov, H., L. Kraleva and N. L. Manev, New Bounds for Probability of Error of Coded and Uncoded TQAM in AWGN Channel, Advanced Computing in Industrial Mathematics, 681 (2017)]. Hence a simple modification of the upper bound can be used in practice for evaluating the SER.