Wireless Microphone Array System

Our past research has focused on wired microphone arrayshaving a large number of elements and wide aperture. The wiring for these large arrays is tedious and only a tree structure with intermediate multiplexing of signals workswell. A wireless array alleviates this immense wiring issue,albeit other difficulties are introduced including interferencesin the wireless transmissions, synchronization, the need for automatic self-calibration, and module power, size and mounting. We introduced the first successful wirelessarray system, HMA-III. 

THE HMA-III SYSTEMThe HMA-III system design centered on making small microphone modules that wirelessly and synchronously sent uncompressed PCM-audio data from a single microphone inreal-time to a standard PC. A block diagram of the moduleis shown in Figure 1 and one of the modules is shown withthe cover off and labeled in Figure 2. For the proof-ofconceptfirst design, we traded off size for ease of designand debugging so each module was packaged in a box thatis about 3”x5”x1”.

Figure1: Wireless array schematicFigure1: Wireless array schematic

Figure 2: Wireless array unitFigure 2: Wireless array unit