As from wikipedia: Cognitive radio is a paradigm for wireless communication in which either a network or a wireless node changes its transmission or reception parameters to communicate efficiently avoiding interference with licensed or unlicensed users.
This is one of the current core research topics of Nokia Research:
Cognitive radio is one of the core research topics of Nokia Research. Faster data transmission in Long-Term Evolution (LTE) will enable new mobile use cases and increase the quality of current services, but we are already taking steps to the future in cognitive radio. We aim to empower a new realm of devices and services through optimised connectivity, where devices use the available spectrum in a dynamic and flexible fashion.
Here’s a recent video looking at the work Nokia has been doing with cognitive radio, very interesting: