Sparse Plane-wave Decomposition for Upscaling Ambisonic Signals

Abstract

Lower order ambisonics suffers from low spatial resolution, where hardware complexity is high for direct recording the higher order ambisonics (HOA). This problem can be solved by upscaling the order-l ambisonics (B-format signals). In this paper, a sparse plane-wave decomposition method using sequential matching pursuit is developed for upscaling the order of ambisonics. The proposed method maintains the same sparsity level across multiple measurements and is computationally efficient. The performance of the proposed method is evaluated based on the error in encoded signal and reconstructed sound field, and compared with the state-of-art upscaling techniques. Perceptual evaluations are also conducted, which indicates a significant improvement in spatial resolution.