The paper presents a method for improving spatial resolution of first-order ambisonic audio. The method is based on time/frequency decomposition of the audio with subsequent extraction of a directed plane wave from each frequency component. The method develops the basic ideas of high angular resolution planewave expansion (HARPEX) and directional audio coding (DirAC) taking advantage of real-valued sparse decomposition. Real-valued frequency components as opposed to complex-valued introduce simpler and more stable direction of arrival estimates, while sparse decomposition introduces an accurate and unified approach to describing sounds of different nature from transient to tonal sounds.

翻译：本文提出了一种提高一阶环绕声音频空间分辨率的方法。该方法基于音频的时频分解，并从每个频率分量中提取定向平面波。该方法发展了高角度分辨率平面波扩展（HARPEX）和定向音频编码（DirAC）的基本思想，利用实值稀疏分解的优势。与复数值相比，实值频率分量引入更简单、更稳定的到达方向估计，而稀疏分解则引入了一种准确且统一的方法，用于描述从瞬态音到音调音等不同性质的声信号。