A Two-Stage Sensing Technique for Dynamic Spectrum Access

Dynamic spectrum access (DSA) is a promising approach for mitigating spectrum scarcity. Underlying DSA is the need for fast and reliable spectrum sensing over a potentially large band. In N.M. Neihart, et al., (May 2007), the concept of two-stage sensing scheme was introduced. In this work, we develop models for performance analysis based on mean time to detect an idle channel. Simulation results show that two-stage sensing leads to faster detection than conventional single-stage random search. System-level issues such as the impact of bandwidth of coarse sensing block and sensing duration of energy detector on mean detection time are also explored.