"Cognitive radio - the next-generation radio technology to alleviate the spectrum scarcity problem"
Duo (Dustin) Zhang
Abstract:
Radio frequency (RF) spectrum is an increasingly valuable resource tightly regulated by governments. However, current radio technologies cause severe spectrum under-utilization; the average spectrum occupancy from 30MHz to 3GHz measured in New York city was only 13%. Meanwhile, the spectrum scarcity is another challenging problem. For example, only in the frequency range of ISM 2.4GHz, Bluetooth devices, cordless phones, WiFi 802.11b/g/n, and microwave ovens, have to coexist.
Such a huge imbalance between spectrum scarcity and spectrum under-utilization is especially lagging today's high-speed wireless networking. To alleviate the imbalance, cognitive radios (CR) have emerged as attractive candidates that enhance radio spectrum-utilization efficiency on both licensed bands and license-free bands.
In the presentation, the concept of cognitive radio and the key components of the cognitive radio will be introduced. I will also show challenges, examples of solutions such as EKF (extended Kalman filter) based adaptive games, capacity comparison of narrowband and wideband cognitive systems, as well as open problems for cognitive radios.