In this thesis we studied method of subtractive interference cancellation applied to multiuser systems. We developed algorithms for simulation of a point-to-point communication system that uses the techniques of interference cancellation. Initially we made a choice of the optimal modulation technique, pulse shape and its corresponding roll-off factor, which improve the bandwidth efficiency. The next step was to generate adjacent channels to our channel of interest and study the degradation of the BER performance for different frequency separation between the channels. Further we explored the SIC and PIC techniques applied in one and two stages. For the one stage implementation our simulations indicate that the BER of the PIC technique is slightly better. The results for the two stages implementation scheme show a clear improvement over the single stage scheme. However, in this case the SIC technique performs visibly better. By using the IC techniques we can pack the channels much closer on a given frequency band such that there is a place for more channels, i.e., users.