To address communication interference in complex noise environments inside and outside helmets,this study aims to improve the acoustic communication quality of in-helmet systems.A four-element microphone array communication hardware system was designed and implemented for use within the confined space of a helmet.Based on simulations of the internal acoustic field,the system incorporates a set of signal processing techniques,including array beamforming,echo cancellation,stationary noise speech enhancement,non-stationary noise suppression,and automatic gain control,forming a complete voice signal processing framework.Experimental results show that the proposed in-helmet microphone array noise reduction system achieves favorable downlink voice clarity under a total noise level of 85 dB(A),preliminarily validating the effectiveness and applicability of the implemented algorithms.This research provides essential technical and theoretical support for the future design and development of open-form in-helmet communication systems.