Modular and scalable directional audio array with novel filtering

Abstract

A directional sensor array system generally for remote audio collection applications that is modular, scalable, and robust with the modules assembled in layers. The invention can alternatively employ sensors other than microphones, such as ultrasonic transducers and accelerometers. In the preferred embodiment, the sensors are mounted on tiles, each of which performs its own local beamforming using a low-impedance resistive summation technique. The tiles are constructed in a layered, sandwiched fashion and incorporate integral protection from wind, sand, dust, moisture, radio frequency noise, vibration, ambient acoustic noise, and directional acoustic noise, as well as provide inter-sensor isolation. Multiple tiles can be joined together physically and electrically. When joined, a secondary parallel beamforming is performed on the bus using electrical summation. Due to the techniques employed, large scale arrays are feasible at low power consumption—for example, an array of 400 microphone elements can be powered for over 6 hours by a single 9 volt battery.