Explain the theoretical underpinnings of cognitive radio and its potential to improve spectrum utilization in wireless communication networks. Cognitive radio involves concepts such as spectrum sensing, spectrum sharing, and dynamic spectrum access, enabling intelligent radios to adaptively select and utilize available radio frequencies based on environmental conditions and user requirements. By integrating machine learning techniques and game theory principles, engineers can design cognitive radio systems that optimize spectrum utilization, mitigate interference, and enhance network capacity and reliability, enabling the seamless coexistence of heterogeneous wireless devices and services.