Single-Hop Transport Throughput of Secondary Networks in Spectrum Sharing Systems

In order to improve the spectrum efficiency, spectrum sharing systems allow multiple systems to utilize the same spectrum with different priorities. Typically, the primary network performs as a stand-alone network while the secondary one accesses the spectrum only if it does no harm to the primary receivers. In this paper, the configuration of the secondary network is of our interest and we explore its single-hop transport throughput (STT) with outage constraints imposed on both networks. STT is a new metric that inherits the merits of both the traditional transport capacity and transmission capacity, incorporating transmission distance and outage probability into a uniform framework. Given the settings of the primary network, we first evaluate the limit of the secondary STT, single-hop transport capacity (STC). Then, we investigate STT with secondary receivers randomly located in the field of interest. To provide a comprehensive view of achievable secondary network throughputs, three models regarding the selection of receivers are considered: optimally selected, randomly selected, and the nearest neighbors. Our theoretical analysis are well substantiated by numerical and simulation results.