论文标题
在网格压缩样本上,用于声学的球形场测量
On Grid Compressive Sampling for Spherical Field Measurements in Acoustics
论文作者
论文摘要
我们在预定义的球形网格上使用场测量得出了一种用于声场重建的压缩抽样方法,从理论上保证了信号稀疏,测量数和重建精度之间的关系。该方法可用于重建带有稀疏系数的球形谐波或Wigner $ d $功能系列(球形谐波系列是特殊情况)。对比鲜明的Wigner $ d $ dunction系列的典型压缩抽样方法,使用任意随机测量,新方法样本在Equiangular Grid上随机样本,这是一种实用且常用的采样模式。使用其定期扩展,我们将Wigner $ d $功能系列的重建转换为多维傅立叶域重建问题。我们确定这种转变对稀疏度具有有限的影响,并提供了对此效果的数值研究。我们还比较了新方法的重建性能和现有的压缩抽样方法的重建性能。在我们的测试中,新的压缩抽样方法与其他保证的压缩抽样方法相当,并且需要一小部分由Nyquist采样定理决定的测量。此外,使用三分之一的测量或更少的测量值,与经典傅立叶理论相比,新的压缩抽样方法可以提供超过20 dB的能力。
We derive a compressive sampling method for acoustic field reconstruction using field measurements on a predefined spherical grid that has theoretically guaranteed relations between signal sparsity, measurement number, and reconstruction accuracy. This method can be used to reconstruct band-limited spherical harmonic or Wigner $D$-function series (spherical harmonic series are a special case) with sparse coefficients. Contrasting typical compressive sampling methods for Wigner $D$-function series that use arbitrary random measurements, the new method samples randomly on an equiangular grid, a practical and commonly used sampling pattern. Using its periodic extension, we transform the reconstruction of a Wigner $D$-function series into a multi-dimensional Fourier domain reconstruction problem. We establish that this transformation has a bounded effect on sparsity level and provide numerical studies of this effect. We also compare the reconstruction performance of the new approach to classical Nyquist sampling and existing compressive sampling methods. In our tests, the new compressive sampling approach performs comparably to other guaranteed compressive sampling approaches and needs a fraction of the measurements dictated by the Nyquist sampling theorem. Moreover, using one-third of the measurements or less, the new compressive sampling method can provide over 20 dB better denoising capability than oversampling with classical Fourier theory.