Spatio-Temporal Dynamic Spectrum Allocation with Interference Handling

As for today, radio spectrum resource is rigidly partitioned for dedicated purposes. The exclusive license of fixed size spectrum blocks separated by guard bands easily solves the interference problems; however, the rigid allocation of spectrum is clearly inadequate for providing optimal spectrum efficiency for spatially and temporarily varying loads. Dynamic spectrum allocation (DSA) is a new and promising alternative where the assigned spectrum blocks may vary in time and space, too. In this paper we describe a spatio-temporal DSA model that splits the complex problem into temporal and spatial dynamic spectrum allocation. In our architecture the spectrum is allocated by regional spectrum brokers (RSB) that also coordinate spectrum access between regions. The problem of interference between different regions and providers is handled by a flexible description using the proposed geographical and radio technology coupling parameters. We also show how the optimal allocation can be found by giving the ILP solution to the problem. To evaluate the efficiency of the proposed DSA method, different gains are defined from the regulator´s point of view. The performance evaluation is carried out using computer simulations, and the results are compared with the cases where either there is no interference allowed at all, or interference does not occur between regions.