Abstract: A real-time, or synchronous, sensor data acquisition system acquires physical characteristics or properties associated with a structure or physical system using a plurality of sensors coupled in series to a single cable. The sensors may sense vibration, noise, temperature, acceleration, pressure, strain, force, etc. The sensors transmit data along the cable at greater than 100 dB dynamic range, with a bandwidth between about 5 to 20 KHz, and in a digital, single bit wide data stream. The sensors include modulators to code the data signals with distinct codes. A receiver has a demodulator to decode and separate the data signals.

Abstract: An apparatus and method for simulating a human mastoid is disclosed. The apparatus includes a diaphragm having a mass, springiness and damping means sufficient to more closely replicate the impedance of a human head bone and skin overlying the same, than prior art testing devices. In a preferred embodiment, the method includes placing the diaphragm over the central opening of an artificial ear and placing a bone conduction hearing aid on top of the diaphragm. A microphone disposed below the opening measures the sound generated by the vibration. These measurements provides an indication of whether the bone conduction hearing aid is functioning properly. The apparatus and method are not only easier to use and less expensive than prior art devices and methods, they are also as accurate, if not more accurate.

Abstract: An apparatus and method for simulating a human mastoid is disclosed. The apparatus includes a diaphragm having a mass, springiness and damping structure sufficient to more closely replicate the impedance of a human head bone and skin overlying the same, than prior art testing devices. In a preferred embodiment, the method includes placing the diaphragm over the central opening of an artificial ear and placing a bone conduction hearing aid on top of the diaphragm. A microphone disposed below the opening measures the sound generated by the vibration. These measurements provides an indication of whether the bone conduction hearing aid is functioning properly. The apparatus and method are not only easier to use and less expensive than prior art devices and methods, they are also as accurate, if not more accurate.

Abstract: An intensity acoustic calibrator is disclosed including at least two wave guide channels. A speaker adjacent each wave guide channel emits sound to develop a standing wave pattern at the opposing end of the channel. The test microphone is positioned in the calibrator so as to be in acoustic communication with the wave guide channel so that the microphone can be calibrated respective to the standing wave pattern. By having two separate wave guide channels and speakers, the test microphones can be subjected to arbitrary magnitude changes and phase differentials. Additionally, a reference microphone may be positioned adjacent each wave guide channel to monitor the sounds generated by the speakers to ensure that the speakers are emitting sounds at the desired magnitude, phase, etc.