TABLE OF CONTENTS The motivations for network support for cognitive radio are threefold:
With powerful network support, the requirements on cognitive radio user equipment could be significantly relaxed because many computation-intensive cognition functionalities can be realized at the network side. Distributed and collaborative information processing over the network can reduce the workload of single user's equipment and speed up the adaptation process of cognitive radio. This is an important strategy to facilitate the commercialization of cognitive radio technology, considering the many constraints imposed on costsensitive user equipment, such as limited battery power, signal processing capability, and memory footprint.
Key cognitive functionality, such as incumbent primary user (PU) detection, cannot be reliably accomplished by user equipment itself due to the shadowing or fading effects of radio propagation and the practical system limitations of the sensitivity, dynamic range, and the noise floor [1, 2]. The radio has to resort to network support for many situations to solve the hidden node problem and achieve the operational goals of cognitive radio.
Network support is critically important to the evolution of wireless communications from legacy radios to cognitive radios, and from...
