Abstract
In real-time communication, the bandwidth required by traffic may fluctuate over time, and the network should allocate spectrum flexibly to satisfy such demands. In this paper, a novel spectrum assignment scheme is proposed. It reduces the spectrum fragmentation by minimizing the number of spectrum-free windows and establishes a virtual sub-connection in a non-contiguous spectrum block for the incremental bandwidths of time-varying traffic, to eliminate the traffic relocation and interruption caused by traffic change. Numerical results demonstrate that the scheme proposed in this paper effectively reduces the network blocking probability, decreases the traffic interrupt ratio, and improves the performance of serving traffic.