Dynamic Spectrum Access Strategies in the Cognitive Radio Network Based on the Discrete TV Band
LU Yan-hu · Journal of Zhengzhou University · 2015
The unused TV bands are discretized by the behaviors of the random presence of the incumbents,considered as primary users in the cognitive radio network. The spectrum discreteness is ignored by most of the existing strategies,resulting in a mass of spectrum fragments that cannot afford the user's demand. In the paper,the primary users are modeled as a Markov process,and the spectrum occupancy degree,fragments degree and the statistical average outage probability are defined to analyze the impact of the primary users on system performance. And two strategies are proposed in this paper. The first strategy involves adjustment factor and selects the fewer continuous channels. The second strategy based on the k-agile receiver involves the constraint of agility and guard bands,and selects the minimum non-contiguous fragments to solve the fragments problem in the physical layer. The simulations show that both strategies are superior to the existing strategies.