Measurement of directional information in sound fields

The directional characteristics of sound arriving at a listening point in a room are being studied with a view to improving microphone pickup of speech in teleconference rooms. Knowledge of the directions from which the direct, reflected, and reverberant sounds arrive is expected to be useful in microphone array design. At present, there exist several techniques which attempt to measure the direction of sound arrival, based on comparisons and postprocessing of multiple microphone signals. This postprocessing can involve intensity analysis, deconvolution analysis, or cross‐correlation analysis. Each of these approaches has its benefits, drawbacks, and tradeoffs, and may perform better or worse in a given situation. Studies of several of these directional measurement techniques are underway to ascertain their usefulness and validity in a variety of situations, through both simulations and real room measurements.