Online Metrological Study Of Environmental Noise Monitoring Terminal

As the environmental noise monitoring instrument, Environmental NoiseMonitoring Terminal (ENMT) lacks of the verification Regulation and related onlinemetrological verification method, which leads to the result that ENMT can’t beverified after they are mounted. The suitable method is put forward to ENMT by thecomparison, analysis of metrological methods between JJG188-2002and theIEC61672-3-2006. The feasibility of JJG188-2002to ENMT is discussed, if it is onthe occasion that ENMT is under verifying based on JJG188-2002. The implementssteps as follows:Step one, the design ideas of hush tube which is used to verify the parameter offrequency weighting with acoustic signal are raised. It includes sound insulationrequirements and mounted place of microphone based on the acoustic field theory.Eventually, the measurement uncertainty component, produced by the mounted errorof microphone, is deduced based on standing wave theory.Step two, design and develop verification program for ENMT. Firstly, it enablesthe verification program to control signal analysis instrument to produce, collect andanalyze signal by the investigation of interface program of PULSE; Secondly, itrealizes the verification program to control the parameters of ENMT by studyingcommunication protocol of ENMT. Finally, the verification process parameters ofENMT become easier and more effective benefit from the verification program.Step three, the experiments and studies are performed with the utility of thementioned methods and instruments above. At the beginning, the inner sound fielddistribution of hush tube is performed by experiments data, meanwhile, the factorswill affect the verification result, as background noise and windshield, are put on thefirst place of experiment list. Moreover, it has a various influence ability on differentfrequency. Afterwards, the parameters of ENMT are performed. It is concluded thatthe uncertainty of experiment data obtained by the utility of hush tube is higher thanthe JJG188-2002required, which also brings about the result exceeds the MPE of frequency weighting. Last but not the least, the verification regulation is urgentlyneeded for ENMT, so that ENMT could give people a convictive and authoritativemeasurement result.