| 摘要: |
| 为了探索中低速率编解码算法在语音光通信方面的应用，设计了一套基于FPGA（现场可编程门阵列）和AOM(声光调制器)的μ律算法语音光通信系统；系统优化了μ律语音编解码算法，并将其移植到FPGA中，采用大气信道，双光路，全双工工作方式；光源为637 nm激光器和大功率LED，对激光器采用AOM(声光调制器)进行外调制，对LED进行内调制；利用系统进行了近距离双工通信和室内80 m距离通信实验，传输速率80 kbps，MOS≥3.0，信道误码率分别低于0.000 1%和0.001 2%，持续通话时长分别为2.3 h和1.5 h；结果表明：通信系统可以实现中低速率语音光通信。 |
| 关键词: FPGA μ律算法 光通信 语音编解码 声光调制器 |
| DOI： |
| 分类号: |
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| A Voice Optical Communication System Based on FPGA and Acoustic Optical Modulator |
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GUO Cheng1, XIAO Sha li1, PENG Guang hui2,LIU Feng1, MA Yue dong1
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| Abstract: |
| A voice optical communication system based on FPGA and acoustic optical modulator(AOM) was proposed to explore the low rate codec algorithm for voice communication. The μ law algorithm for voice codecs was optimized and then transplanted in FPGA. The communication system, which adopts atmospheric channels, is conducted in double optical path and full duplex mode. Light sources of the system consist of a high power internal modulated LED and a 637 nm all solid state laser which is external modulated by AOM. For performance evaluation, a short range communication experiment and a indoor 80 m communication experiment were conducted. In view of the above two cases, the achieved serial communication rate is both 80 kbps, and MOS rate is both higher than 3. However, the bit error rate for the 2 experiments is lower than 0.0001% and 0.0012%, and the call duration is 3 h and 1.5 h, respectively. Experimental results showed the capacity of using the system for low bit rate speech optical communication. |
| Key words: FPGA μ law algorithm optical communication Acousto optical Modulators Speech Codec |
