No abstract

An accurate measurement of noise wave is the key to effective noise control in a tunnel. In this paper, an IP based audio test network is presented. This network includes 100 battery powered recorders and a WIFI network. Each recorder can acquire 2 channels of audio waves and be triggered by external signals of infrared or electrical synchronic pulse. A main control computer connects these recorders to setup parameters and collect data via the WIFI network. Sensors are reassembled to be compatible with the interface of standard sound source. Meanwhile each sensor is fixed in a sensor holder, which can be placed to any position on a plane and can be used to adjust its sensor to 0-180 degrees in both of X-Y direction. The sound source generates various signals, such as clicks, tones, and tone bursts, to help understand how the sound propagates in tunnels. This designed network is capable of acquiring multipoint sound waves synchronously.