Frequency Agile Waveform Adaptation for Cognitive Radios

In the context of cognitive radio (CR) networks, this paper develops a frequency-agile waveform adaptation technique that dynamically adjusts the spectral shape, power and frequency of transmission waveforms for efficient network spectrum utilization. A general framework is presented based on generalized transmitter and receiver basis functions, which allow to jointly carry out dynamic resource allocation (DRA) and waveform adaptation, two procedures that are traditionally carried out separately. New objective function and cognitive spectral mask constraints are formulated for DRA optimization tailored to CR applications. The joint DRA and waveform adaptation approach permits distributed games in multiple access networks, in which participating CR users optimize their respective local utility functions by taking actions from the action space defined by allowable basis function parameters. It results in not only enhanced radio spectrum resource efficiency due to joint optimization, but also affordable complexity scalable in the network size, by virtue of the distributed game approach adopted.