A simple mechanism for capturing and replaying wireless channels

Physical layer wireless network emulation has the potential to be a powerful experimental tool. An important challenge in physical emulation, and traditional simulation, is to accurately model the wireless channel. In this paper we examine the possibility of using on-card signal strength measurements to capture wireless channel traces. A key advantage of this approach is the simplicity and ubiquity with which these measurements can be obtained since virtually all wireless devices provide the required metrics. We show that for low delay spread environments wireless traces gathered using this method can be replayed in a physical wireless emulator to produce higher layer network behavior that is similar to the behavior that would have occurred in the real world. Thus, wireless channel traces gathered using on-card metrics are an effective means of enabling existing low delay spread wireless testbeds to be emulated.