On Room Impulse Response Measurement Using Orthogonal Periodic Sequences

Abstract

The paper discusses a measurement method for the room impulse response (RIR) which is robust towards the nonlinearities affecting the power amplifier or the loudspeaker used in the measurement. In the proposed approach, the measurement system is modeled with a Volterra filter. The first order kernel of the Volterra filter, i.e., the linear part, is efficiently determined using orthogonal periodic sequences (OPSs) and the cross-correlation method. The approach shares many similarities with RIR measurements based on perfect periodic sequences (PPSs). In contrast to PPSs, the proposed approach is able to directly measure the impulse response for small signals of the measurement system. Moreover, the input signal can be any periodic persistently exciting sequence and can also be a quantized sequence. Measurements performed on an emulated scenario compare the proposed approach with other competing RIR measurement methods.