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CTA Communications <br />Orange RaCE Test Report <br />5.0 Definitions And Process <br />5.1 Channel Performance Criterion <br />The channel performance criterion (CPC) describes the radio system <br />performance /understandability in terms of a specific threshold signal level (median <br />microvolt level) or threshold delivered audio quality value (DAQ). <br />5.1.1 Delivered Audio Quality <br />The delivered audio quality (DAQ) designations used in this document are defined by <br />TIA/EIA TSB -88 -B as shown in TABLE 5 -1. For the purpose of this test, we used a CPC <br />of DAQ -3. The DAQ field test measurement data were post - processed and the results <br />are included in the coverage maps provided with this report. The coverage maps indicate <br />three ranges: no access, DAQ 0 to 2.99 and DAQ 3 to 5. <br />Table 5 -1 Delivered Audio Quality Definitions <br />Delivered <br />Audio ouality <br />Performance Definition <br />DAQ -0 <br />No Speech Detected (CTA Definition) <br />DAQ -1 <br />Unusable, speech present but unreadable; SINAD equivalent <br />intelligibility: less than 8 dB <br />DAQ -2 <br />Understandable with considerable effort; frequent repetition due <br />to noise and distortion; SINAD equivalent intelligibility: 12 dB <br />DAQ -3 <br />Speech understandable with slight effort; occasional repetition <br />required due to noise and distortion; SINAD equivalent <br />intelligibility: 17 dB <br />DAQ -3.4 <br />Speech understandable with repetition only rarely required; <br />some noise and distortion; SINAD equivalent intelligibility: 20 dB <br />DAQ-4 <br />Speech easily understood; occasional noise and distortion; <br />SINAD equivalent intelligibility: 25 dB <br />DAQ -4.5 <br />Speech easily understood; infrequent noise and distortion; <br />SINAD equivalent intelligibility: 30 dB <br />DAQ -5 <br />Speech easily understood; SINAD equivalent intelligibility: <br />greater than 33 dB <br />- 9 - H MM ,AECO 1 <br />