Channel Modeling for MCvD Systems in the Presence of a Time-Varying Node

Accurate channel modeling is crucial for molecular communication via diffusion (MCvD) system. Most existing studies assume that the channel impulse response (CIR) is time-invariant. However, real MCvD environments often exhibit time-varying behavior, making this assumption unreliable and potentially causing significant discrepancies between theoretical analyses and practical outcomes. While previous research has primarily focused on the impact of transceiver mobility on time-varying channels, the effect of state changes at nodes has received little attention. To address this gap, this paper characterizes the channel in MCvD systems with a time-varying node and derives the corresponding CIR. Simulation results show excellent agreement with the theoretical CIR, validating the accuracy of our model and providing a novel approach for analyzing time-varying channels in MCvD systems.