Performance Evaluation of Cognitive Radios: Metrics, Utility Functions and Methodologies

The selection and design of performance metrics and utility functions is an important, but inadequately addressed issue in the design of cognitive radio networks. Unlike traditional radios, a cognitive radio may change its objectives as radio scenarios vary. Because of the dynamic pairing of objectives and contexts, it is imperative for cognitive radio network designers to have a firm understanding of the inter-relationships between goals, performance metrics, utility functions, link/network performance, and operating environments. In this paper, the authors first overview the hierarchical metrics for evaluating the performance of cognitive radios from the node, network, and application levels.