Intelligibility of Analog FM and Updated P25 Radio Systems in the Presence of Fireground Noise: Test Plan and Results.

摘要

In 2008, the Institute for Telecommunication Sciences (ITS) developed and conducted a test designed to measure the intelligibility of land mobile radio (LMR) systems in the presence of fireground noise. The test showed that fireground noise environments were especially challenging for the digital speech coder component of the Project 25 (P25) LMR system. ITS published a report describing the test. This report was distributed widely among the public safety community and resulted in the establishment of a set of new best practices that were intended to increase intelligibility performance in extreme conditions. Additionally, the digital speech coder used in P25 LMR systems was enhanced in order to address operation in typical fireground noise environments.