Modeling radio resource management in cognitive radio system based on OFDMA using colored Petri Net

Abstract

Cognitive Radio (CR) system based on Orthogonal Frequency Division Multiple Access (OFDMA), such as Wireless Regional Area Networks (WRAN) and Worldwide Interoperability for Microwave Access (WiMAX), often attempt to improve performance via dynamic radio resource management, which is characterized as concurrent processing of different traffic and nondeterministic system capacity. It is essential to design and evaluate such complex system using proper modeling and analysis tools. In the previous work, most of the communication systems were modeled as Markov Chain (MC) and Stochastic Petri Nets (SPN), which have the explicit limitation in evaluating adaptive OFDMA CR system with wide area traffic. In this paper, we develop an executable top-down hierarchical Colored Petri Net (CPN) model for adaptive OFDMA CR system, and analyze its performance using CPN tools. The results demonstrate that the CPN can model different radio resource management algorithms in CR Systems, and the CPN tools require less computational effort than Markov model using Matlab, with its flexibility and adaptability to the traffics which arrival interval and processing time are not exponentially distributed.

Modeling spectrum access strategies in cognitive radio networks using Colored Petri Nets

“…And the smaller the ratio, the more the results agree. It is because the CPN and MC possess the isomorphic state space, demonstrated in [11], that we can get the result in Fig.10. If the arrival and service rate are fixed, we can also get an appropriate value for N. As shown in Fig.11 Fig.…”

“…The less computational complexity makes it flexible and adaptable to different scenarios. However, our research in [11] has shown that it is inevitable for SPN to come into being tremendous state space, which is similar to MC, with the increasing places and transitions of the model in systems. Especially, when the users arrive with non-exponential distribution, such as Binomial, Discrete, etc, the condition becomes worse.…”

“…Especially, when the users arrive with non-exponential distribution, such as Binomial, Discrete, etc, the condition becomes worse. To solve this problem, the CPN modeling was proposed to evaluate the multi-traffic call access control strategy in our previous researches [10], [11] and [12], which can remit the space explosion problem through a top-down hierarchical function decomposition. Considering the CPN and MC possess the isomorphic state space, [13] proves the CPN model can also be used in the field of spectrum handoff.…”