In this report, we investigate radio communication problems faced by emergency responders (firefighters, police and emergency medical personnel) in disaster situations. A fundamental challenge to communications into and out of large buildings is the strong attenuation of radio signals caused by losses and scattering in the building materials and structure. Beside attenuation, another challenge is the large amount of signal variability that occurs throughout these large structures. We designed experiments in various large building structures in an effort to quantify radio-signal attenuation and variability faced by emergency responders. We carried RF transmitters throughout these structures and placed receiving systems outside the structures. The transmitters were tuned to frequencies near public safety, cell phone bands, as well as ISM band, including wireless LAN frequencies. This report summarizes the experiments, performed in twelve large building structures. We describe the experiments, detail the measurement system, show primary results of the data we collected, and discuss some of the interesting propagation effects we observed.
Technical Note (NIST TN) - 1545
attenuation, building shielding and coupling, emergency responders, radio communications, radio propagation experiments, signal variability, weak-signal detection