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In-Building Radio Enhancement Systems for Public Safety

Report ID
NTIA Technical Report TR-11-480
September 01, 2011
Robert J. Achatz, Roger A. Dalke and John J. Lemmon

Abstract: Reliable public safety communications between system repeaters outside a building and portable radios inside a building is often not possible due to building attenuation. To circumvent this problem, increasing numbers of municipalities are requiring building owners to provide in-building radio enhancement systems (IBRESs) for public safety communications. This report is intended to be used by public safety communications professionals who are tasked with assisting building owners to fulfill this requirement. The main body describes IBRES technology, problems endemic to it, and solutions to these problems. Appendices provide detailed data tables, theory, calculations, and measurements that support assertions made in the main body.

Keywords: Bi-directional amplifiers; building attenuation; distributed antenna system; in-building radio enhancement system; land mobile radio; link budget; public safety radio; radio-wave propagation

The full report is available at