Impedance matching based cross-layer architecture for cognitive networks

One of the main challenges faced by communication field is the efficient utilization of precious resources (e.g., spectrum). To handle this issue, Cognitive Networks (CNs) are proposed with flexible adaptation and dynamic adjustment to the heterogeneous environment. In CNs, cross-layer design that relies on the interaction and cooperation of nonadjacent layers is a potential way to alleviate and cope with the unique issues created by traditional layered architecture. Nevertheless, the existing cross-layer designs server to highlight specific shortcomings of the layered architecture and are always protocol stack centric, paying little attention to the unified platform of various cross-layer schemes. To deal with the coexistence problem, this paper concentrates on the compatibility of cross-layer schemes and depicts a novel Impedance Matching based cross-layer Architecture (IMclA) for communication and networking. The architecture abstracts the scenarios of time-varying and error-prone surroundings as source impedances, and regards the diverse cross-layer strategies as specific load impedances that match in accordance with the source impedances. IMclA provides a universal platform for implementing cross-layer strategies in CNs, with detailed design of handshake mechanism for control signals. Moreover, a matching algorithm with low complexity is illustrated. For evaluation, we focus on the queue manner of the impedances in terms of efficiency and fairness that have a profound influence on the overall system performance and stability. Simulation results, demonstrating the operating and processing time of impedance matching approach based on M/G/1 model, show that the system sojourn time could reach a preferable value as the priority numbers increase to a high degree.