On 8/28/2010 8:38 AM, nj902 wrote: > > Because a mobile radio really has no way to provide a meaningful delivered > audio quality indication, coverage acceptance testing of analog systems is > usually done by measuring carrier level at [mobile] locations throughout the > system's service area and using DAQ equivalence as defined in TSB-88 to > determine whether the values measured meet coverage requirements. > > During these coverage acceptance tests, the system base station carrier is > unmodulated, thus the measured values have no relationship to the bandwidth > of the system and would be identical for a given base station transmit power > - regardless of which mode it is programmed for. Correct. Which is also why measuring DAQ equivalent this way is pretty much useless for anyplace that has substantial terrain (hills and mountains) or even reflective urban structures that aren't in the center of the coverage area (highrise buildings in a suburban area that is some ways away from the transmitter).
Most of the audio quality problems that result in unintelligible signals at the edge of the coverage are caused by flutter and multipath, neither of which is detectable by looking at the level of an unmodulated carrier. Matthew Kaufman
