Performance of the buffer queue with priority for Dynamic Spectrum Access

In this paper, we propose a new Dynamic Spectrum Access (DSA) scheme which employs a buffer queue with priority. Two coexist systems: primary system and secondary system are introduced, which share the same bandwidth. When all the bands are busy, the newly coming secondary user (SU) is inserted into the buffer queue according to the user´s priority. The average waiting time and the average queue length of this model are studied. The simulation results indicate that our model can obtain a good tradeoff between average waiting time and interrupted probability. It may reduce the average waiting time of the higher priority user, also, although the average waiting time of the lower priority user increases, their interrupted probability reduces.