CAJ | 학술논문

为实现复杂声源局部声场精确重建，提出基于改进的HELS法的局部近场声全息（PNAH）技术。将实际声场视为声源各部分产生相干声场的叠加，利用小全息孔径测量声压求解正交基函数的线性组合系数，实现全息声压近场外推；用外推所得数据进行声场重建。仿真及实验结果表明，该方法能有效重建复杂声源声场，且重建精度较高。
위실현복잡성원국부성장정학중건，제출기우개진적HELS법적국부근장성전식（PNAH）기술。장실제성장시위성원각부분산생상간성장적첩가，이용소전식공경측량성압구해정교기함수적선성조합계수，실현전식성압근장외추；용외추소득수거진행성장중건。방진급실험결과표명，해방법능유효중건복잡성원성장，차중건정도교고。
Fast Fourier transformation (FFT )-based near-field acoustic holography (NAH ) requires that measurement aperture should completely enclose a source,but it is impractical for large-scale sound sources.Helmholtz equation least square (HELS ) method allows patch acoustic field reconstruction. However, it's not suitable for reconstructing acoustic radiations from coherent multiple sources or a complicated source consisting of several separated parts.To overcome this difficulty and enhance reconstruction accuracy,a new patch NAH technique based on the modified HELS method was proposed.The acoustic field of a complicated source was expressed as the superposition of coherent acoustic radiations from all of its separated parts with the modified HELS method.Using the acoustic pressures reconstructed with the modified HELS method,the measurement surface was extended through an iterative procedure. Finally,taking the extrapolated pressures as input data,the acoustic field was reconstructed more precisely.Numerical simulation and experimental results demonstrated that this method can be used to reconstruct the acoustic field of a complicated source and raise the reconstruction accuracy.