Adaptive Cost-Based Probabilistic Offloading for Wireless Networks

This paper investigates adaptive, cost-based probabilistic offloading between two coexisting wireless systems: a type-1 system and a type-2 system that opportunistically exploits idle type-1 resources. The coupled dynamics are modeled as a finite level-dependent quasi-birth–death (LD-QBD) process with explicit block structure, enabling exact stationary evaluation. From the stationary distribution, we derive teletraffic-consistent metrics including blocking, dropping, utilization, throughput, and cost-based performance measures. Building on these metrics, we develop a windowed, adaptive admission controller that combines KPI smoothing, cost-aware probabilistic mapping, PI-based regulation, and safety backoff mechanisms. Numerical results demonstrate that the proposed controller effectively balances throughput, admission opportunity, and preemption risk under changing traffic conditions while achieving the lowest overall blocking-and-drop cost among the practically useful policies considered. The framework provides an analytically grounded framework for investigating adaptive opportunistic offloading in wireless networks.