A Testbed for Adaptive Microphones in Ultra-Low-Power Systems

Smart cities bring new technological advances that help improve everyday life. One such improvement is the ability to map out a city based on a characteristic. The amount of acoustic noise in an environment has many impacts on human life and has the potential to be collected wirelessly. Unfortunately, systems made today would not have the battery life capabilities to handle such a high demand if continuous transmission was used. In this paper, the design of a testbed for a smart microphone system is presented. In order to promote power savings, an analog-to-digital converter (ADC) which dynamically switches between high and low power modes in response to environmental noise is presented. Specifically, the high power ADC mode is triggered from a spike in the acoustic noise level. Ideally, this would be configurable and allow for detection of different types of sound such as human voice or music. A framework for basic environmental sound collection is presented along with preliminary results of the testbed.