Synthesis of room transfer function over a region of space by multiple measurements using a higher-order directional microphone

Spatial sound field recording and reproduction in reverberant rooms require the measurement of room transfer functions (RTF) and corresponding compensation such as room equalization to avoid unintended effects. Typically, the RTF rapidly varies over the room and hence requires a large number of point to point measurements to characterize the room. This paper provides (i) an efficient parameterization of the three dimensional acoustic transfer function over a region of space and (ii) a method to merge distributed multiple measurements by a higher order microphone (such as a spherical array) to analyze and synthesize the room transfer function over a region of space. The proposed method is shown to be a practical way of measuring the RTF over large areas with a significantly reduced number of measurements and improved robustness