STSP: Space-time stretched pulse for measuring spatio-temporal impulse response

We propose an efficient method for measuring impulse responses between linear arrays of loudspeakers and microphones with a spatio-temporal stretched pulse (STSP). We derived the STSP by extending a time-stretched pulse (TSP) to the spatial domain; therefore, an STSP is a signal whose temporal and spatial frequencies simultaneously increase with time. When M denotes the number of array elements, the measurement time of impulse responses reduces to 1/M by using STSP compared to multiple measurements with TSPs. Although the impulse response estimated with STSP is an approximated form of that measured with TSPs, this type of impulse response, which is defined as a spatio-temporal impulse response, has advantages in sound field reproduction applications. Numerical simulation results indicated that the spatio-temporal impulse response was well estimated using the proposed method.