Grant: Discovery Grants Program - Individual

The rigid structure of the current spectrum allocation policies creates a bottleneck for rapidly growing wireless users. On the other hand, the Federal Communication Commission (FCC) measurements reveal that most of the licensed frequency bands are either unused or utilized less than 10% of the time. In order to address the limitations on spectrum usage, the FCC has motivated the use of opportunistic spectrum sharing to make licensed frequency bands accessible for unlicensed wireless users. The intention behind this is to create cognitive capability of wireless devices for concurrent spectrum usage. In cognitive networks, users/radios dynamically adapt to their environment through learning or artificial intelligence with the aim of improving the overall network performance. Given the projected smart capabilities of cognitive networks, many challenges such as spectrum sensing/sharing and system identification need to be addressed before actual implementation can take place. This proposal aims at investigating these challenges in an effort to enhance the overall spectrum efficiency in wireless cognitive networks. Specifically we will focus on efficient and low complexity spectrum sensing and blind system identification techniques with emphasis on modulation type/size, number of used antennas, and code design identification. The proposed research program will also involve investigations for joint design of the physical layer parameters and higher networking aspects of the wireless protocol stack in a cross-layer context. The design approach will be based on cognitive communications supported by intelligent architectures at the mobile cognitive end. With the wide applications of cognitive networks ranging from safety, healthcare (e.g., tracking of people with mental disabilities) and transportation, our findings will benefit both research institutions and companies, and hence provide the research communities in both industry and academia with efficient and fast implementations of these applications.