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Built-Environment Signal Propagation and Penetration

Potential in-building propagation environments

Examples of the wide variety of potential in-building propagation environments

Today’s signal-propagation modeling is often based on notions of simple outdoor communications or, if within a building, simple in-room communications. These models fail to account for complex in-building wireless environments, the impact of outdoor wireless signals penetrating into indoor environments, or leakage among systems in neighboring indoor environments, among other scenarios. NIST CTL’s Shared Spectrum Metrology Group is working to quantify such factors, and to do so cost-efficiently with combinations of high-end and low-cost sensors such as existing Wi-Fi access points.

These efforts feed into our work in wireless spectrum forensics as well as in developing new metrics for wireless coexistence.

Specifically, our building-related signal propagation and penetration work involves research and development of a calibrated, distributed spectrum-monitoring system. We collect RF data using localized monitoring in such places as factories, power plants, hospital rooms and stadiums – realistic environments for coexistence testing.

Among the key goals in developing this distributed spectrum monitoring system is to develop effective – and cost-effective – topologies and equipment for in-building signal measurement we can then transfer to industry. The aim is to combine low-cost antennas and other hardware with state-of-the-art probes and associated metrological tools to yield reliable data for use in spectrum-sharing, wireless spectrum forensics, system-engineering and policy decisions.


RF Technology Division

Created June 2, 2016, Updated March 26, 2020