Mapping link SNRs of wireless mesh networks onto an indoor testbed

As a platform for synergistic theory-experiment exploration in the field of wireless networking, wireless testbeds have been used to facilitate a broad range of research. From the perspective of system-level wireless emulation, average link SNR is the dominant factor in the performance of a wireless link. Thus, this work seeks to develop a systematic link SNR mapping method that replicates real-world link SNRs on an indoor testbed. The challenge is to optimize the nodes\´ spatial configuration and transmission powers to overcome the inherent propagation differences, as expressed in terms of pathloss exponents and environmental shadowing, between the real world and a given testbed. To avoid the technical difficulty of "forward mapping" from the real world to the testbed, we have developed a reverse mapping method to turn a testbed configuration with given link SNRs into a corresponding real-world configuration. By inducing the dB link gain differences between the testbed and the real world distance-dependent path loss to have a Gaussian distribution, a close approximation to real-world log-normal shadow fading is achieved. We present results for a variety of indoor and outdoor real-world scenarios