Joint demodulation of a desired transmission and an interfering transmission received from an interfering cell with an unknown combination of transmission parameters is performed. For each subcarrier, an exhaustive search for the serving cell symbols and projection for the interfering cell symbols is performed for tested hypotheses of the interfering cell, by minimizing a whitened noise parabola for each combination of searched hypothesis and hyper constellation point of the serving cell. A constellation point for the interfering cell that is closest to the minimum point of the parabola is selected, where coefficients of the parabola are calculated once for each subgroup of four modulation types of the interfering cell. A measure of likelihood for each of the tested hypotheses is calculated. A cumulative measure of likelihood for each of the tested hypotheses is calculated, and the most likely hypothesis is selected based on the cumulative measure of likelihood.