数字半双工通信机制在楼宇对讲系统中的应用

针对于数字楼宇对讲系统通话声音小、对讲过程中经常出现回声和啸叫等问题，本文基于DM365硬件平台和嵌入式Linux系统设计了一款具有数字语音半双工双向通信机制的楼宇对讲系统。该系统在语音端采用短时能量加过零率的实时语音端点检测算法，能使前端输入的音频信号无衰减，实现高清晰的语音对讲。相对于其他的数字语音通信机制，该系统不仅可以有效地抑制回声。而且能减少因去噪而造成的语音信号失真。

Digital Half-duplex Communication Mechanism Used in Building Speaking System

For the design of digital speaking system in the building, appear small voice calls, the echoes and howling problems occur frequently during intercom. This paper introduces a digital half-duplex two-way communication mechanism can suppress echoes effectively on the DM365 hardware platform and embedded Linux systems building speaking system. It can realize the high clear voice intercom and the input audio signal without attenuation, using the real-time detection algorithm of the shortterm energy and zero-crossing rate on the speech endpoint. Colnpared to other digital voice communication mechanism can avoid echoes and audio signal loss caused effectively by de-noising.