The design and realization of uniform SPL distribution ranging from 1100Hz to 2000Hz

Abstract

In the past research, we have realized that uniform sound pressure level (SPL) distribution ranging from 200Hz to 1000Hz with linear loudspeaker array. With the increase of frequency, the width of the main lobe becomes narrower and the side lobe of the pattern becomes larger. The curve of SPL in the test line also fluxes increasingly evidently. It's difficult to optimize the phase of loudspeaker array exclusively aiming at uniform SPL distribution at frequency higher than 1000Hz. In this paper, we propose a non-equidistant loudspeaker array to optimize, as well as the phases and the distances of array from 1100Hz to 1500Hz. It is difficult to control the increasing side lobe value by only optimizing these two parameters in the array from 1600Hz to 2000Hz. So the amplitude is another parameter to be optimized. We also propose a new parameter representing the degree of energy concentration on the target area which is added to optimize the algorithm. The simulation results show that the relative SPL distribution which demonstrates that the target is implemented accurately and the side lobe is decreased effectively.