On the Optimum Choice of a Threshold in a Frequency Hopping OFDMA System

We consider a frequency hopping orthogonal frequency-division multiple access (FH OFDMA) system different from those previously described. To find the probability density function of the variable used by the detector, we propose an approach based on the characteristic function method and Bessel function technique. Based on this approach, we obtain an expression for the desired density function (in the most probable case of a collision of multiplicity two) and an expression for the optimum threshold value, which enables us to compute it to any desired degree of accuracy. Efficiency of our approach is justified by simulation results.