Abstract
Dynamic spectrum sharing between uncoordinated devices is impaired by interference. Simple coexistence mechanism can reduce this interference and improve network performance. We analyze performance of some simple coexistence mechanisms in detail, where the decision to transmit a packet by a given device to its intended receiver is taken solely by the transmitter receiver pair without any central control. Accurate interference models are developed assuming a large number of transmitter-receiver pairs that are randomly distributed according to a Poisson spatial point process. These are used to derive accurate expressions for packet error rates in the case of direct sequence code division multiple access physical layer model and slotted packet transmission schemes. These results are then used to study the performance of the coexistence mechanisms and compare them with each other.