Coexisting Coverage and Throughput of Multi-RAT Wireless Networks with Unlicensed Band Access

In this letter, the coexisting coverage and throughput of a wireless network consisting of multiple subnetworks of different radio access technologies (RATs) are investigat ed. The coexisting coverage probability that is defined as the sum of the density-weighted coverage probabilities of all subnet works is found in closed-form and it will be shown to have the concavit y over the number of channels in the unlicensed band. The optimal deployment densities of all access points (APs) of differen t RATs that maximize the coexisting coverage probability will be s hown to uniquely exist and found under the derived constraint on network parameters. The coexisting throughput is defined asthe sum of the throughputs of all subnetworks and numerical results show that it is significantly higher than the throughput of the unlicensed band only accessed by WiFi APs.