Abstract-Sound-source localization is used in many different real-time acoustic applications. Microphone arrays have the potential capability to recognize, profile and locate sound-sources in noisy environments. The quality response of such sensor arrays, however, is determined by the quantity of microphones. A higher number of microphones increases the computational demand, making real-time response challenging. In this paper, we present a scalable and runtime reconfigurable architecture to provide accurate sound-source localization in real-time. On one hand, the reconfigurable architecture is designed to be scalable in order to support a variable number of microphones. On the other hand, we use runtime reconfigurable look-up tables (CFGLUTs) to provide a dynamic response in real-time. Experiments demonstrate how an accurate sound-source localization is obtained in less than a few hundred milliseconds. As far as we are aware, it is the first time that runtime reconfiguration is applied to a reconfigurable architecture consisting of a sensor array.
I. INTRODUCTIONMicrophone arrays are becoming popular to many different applications. The localization of sound-sources is applied in the environmental, industrial and military domains. For instance, military applications usually range from localizing sniper fire to identify noisy engine parts. The time response becomes crucial for those vital situations.Due to the recent miniaturization and price drop of good quality microphones in the form of Microelectromechanical systems (MEMS), microphone arrays are rapidly adopting such type of microphones. MEMS microphones are much cheaper than traditional microphones and have a relatively good signal-to-noise ratio (SNR) and frequency response. Their small size allows miniature arrays that are only several centimeters in diameter with a high level of integration.Most of the signal processing demanded by such arrays are traditionally computed in general-purpose processors. The computational demand, however, is directly related to the number of microphones of the array, which is intensely increasing thanks to the low-cost MEMS technology. Thanks to the highcomputational power and low latency response that FPGAs offer nowadays, we believe that FPGAs are not only able to manage relatively large microphone arrays but they also offer a faster response.With the additional number of microphones and real-time applications in mind, we propose a flexible, scalable and runtime reconfigurable architecture able to satisfy the most time demanding sound-source localization applications. Our main targets are the scalability of the system and the capability to dynamically reconfigure the microphone array in order to detect sound-sources in real-time (< 200ms).