This project will examine how crosslayer design can be used to improve the performance of future cognitive networks, including how cognitive principles can be exploited in 5G and beyond 5G networks. Spectrum assignment and routing strategies will be developed which take into account dynamic changes in traffic flow throughout a network. The project will incorporate advanced physical layers, including those that operate with multi-antenna systems. The impact of the degree of control information exchange required between multiple networks and nodes sharing the pooled spectrum, possibly owned by multiple operators, will be addressed. The benefits and drawbacks of such an approach over more traditional techniques will be evaluated. A mixture of simulation and analysis will be used to assess performance. Game theory and Markov analysis will be particularly important analytical tools.