On the capacity of slotted Aloha with Rayleigh fading: the role played by the number of interferers

The role played by the number of interferers and the modulation choice in the performance of slotted Aloha networks with Rayleigh fading is investigated and discussed; the case of multiple transmitted power classes is also considered. A new capture model which takes the number of actual interferers into account is proposed. The network capacity is analytically estimated, and significant differences (depending on the modulation scheme) are found with respect to previously published results carried out by means of more common (and less accurate) capture models, also when the case of different transmitted power classes is considered.