The main contribution of this letter is the derivation of an upper bound BER expression, as a function of distances between signal points, for arbitrary constellations, in a generic, two-transmission scheme such as relaying, HARQ, or CoMP. The approach utilizes the product-state matrix, and thus the arbitrarily chosen constellations together with the encoders do not need to satisfy the quasi-regularity property that includes geometrical uniformity and symmetry. The channel fading is modeled using a Nakagami-m distribution, both with and without correlation between the two transmissions. We also allow for different path loss at each transmission. The results are valid for general coded schemes as long as a transfer function expression can be derived (convolutional codes and trellis coded modulation). The upper bounds are very accurate for BER values lower than 10-2 for any chosen constellation.

Additional Metadata
Keywords Channel coding, Constellation diagram, Convolutional codes
Persistent URL dx.doi.org/10.1109/LCOMM.2015.2513775
Journal IEEE Communications Letters
Citation
Ilter, M.C. (Mehmet Cagri), Yanikomeroglu, H, & Dmochowski, P.A. (Pawel A.). (2016). BER upper bound expressions in coded two-transmission schemes with arbitrarily spaced signal constellations. IEEE Communications Letters, 20(2), 248–251. doi:10.1109/LCOMM.2015.2513775