Vector Network Analyser (VNA) is primarily designed for analysing time-invariant networks, where measurements are conducted one frequency point at a time, with the duration for each point determined by parameters such as the intermediate frequency bandwidth (IFBW) and dwell time. The total measurement time is further influenced by the number of frequency points included in the total sweep. This conventional measurement technique becomes problematic when dealing with time-varying signals, as any changes in the signal must be tracked throughout the entire sweep period. This chapter investigates strategies to adapt VNAs for measuring time-varying transmissions, focusing on their feasibility and limitations. Specifically, it evaluates sweep times using segmented waveforms. We apply experimental validation to construct a measurement scenario investigating dynamic conditions. These measurements and validations will enhance the understanding of time-varying signal measurements and facilitates applications to more complex channel sounder (CS) systems, allowing for improved estimation of associated uncertainties. The work we present in this chapter details the experimental setup, mathematical modelling to simulate a time-varying scenario using a VNA, and the analysis of time intervals recorded for each measured segment under varying velocities. Additionally, it examines the role of optimised reflector positioning for achieving accuracy at each frequency step.