Simultaneous measurement of time-invariant linear and nonlinear, and random and extra responses using frequency domain variant of velvet noise

Abstract

We introduce a new acoustic measurement method that can measure the linear time-invariant response, the nonlinear time-invariant response, and random and time-varying responses simultaneously. The method uses a set of orthogonal sequences made from a set of unit FVNs (Frequency domain variant of Velvet Noise), a new member of the TSP (Time Stretched Pulse). FVN has a unique feature that other TSP members do not. It is a high degree of design freedom that makes the proposed method possible without introducing extra equipment. We introduce two useful cases using two and four orthogonal sequences and illustrates their use using simulations and acoustic measurement examples. We developed an interactive and realtime acoustic analysis tool based on the proposed method. We made it available in an open-source repository. The proposed response analysis method is general and applies to other fields, such as auditory-feedback research and assessment of sound recording and coding.

Cascaded all-pass filters with randomized center frequencies and phase polarity for acoustic and speech measurement and data augmentation

“…Systematic allocation of unit-FVNs enabled simultaneous measurement of the linear time-invariant, the non-linear time-invariant responses and random and time-varying components [6]. Replacing FVN with CAPRICEP also enables a similar simultaneous measurement.…”

“…Replacing FVN with CAPRICEP also enables a similar simultaneous measurement. The following is a brief outline of the procedure in [6].…”

“…Accidentally, we found that FVN provides powerful tools for assessing acoustic systems [6]. FVN is a new member of TSP (Time Stretched Pulse) [7][8][9][10][11][12] in a broad sense.…”

“…It is crucial to acquire reusable speech materials [16,17] and present sound stimuli to participants of subjective tests using adequately prepared sound devices and the environment. FVN also added new functionality to assessment tools [6].…”

“…The following section provides the derivation of CAPRICEP followed by a brief introduction of the simultaneous measurement method of multiple responses. The derivation of this simultaneous measurement method is a replication of the FVNbased method's [6]. CAPRICEP adds flexibility and extended functionality because of its building block, all-pass filter.…”