Dynamic spectrum access is a research area within the field of telecommunications and wireless communication that focuses on the development of technologies and protocols for optimizing the utilization of available frequency bands in the radio spectrum. Traditional approaches to spectrum allocation are often inefficient, as many frequency bands are underutilized or remain unused for long periods of time. Dynamic spectrum access aims to address this issue by allowing devices to opportunistically access available spectrum bands in real-time, based on factors like location, time, and network load. This approach enables more efficient use of the radio spectrum, as it allows for better coordination and sharing of available frequencies among different users and devices. Research in this area involves the development of new techniques for spectrum sensing, spectrum sharing, and spectrum management, as well as the design of protocols and algorithms for dynamic spectrum access in various wireless communications scenarios.