可见光多输入多输出(MIMO)通信中空时分组编码能够获得较高的分集增益, 但是其有效性较差, 空间调制编码能够提高系统的频谱利用率但其可靠性较差。因此结合空时分组编码和空间调制编码的优势设计出空时分组-空间调制(STBC-SM)级联编码应用到可见光MIMO通信系统中, 根据朗伯光源衰减特性建立了可见光室内传输信道模型, 并对系统有效性及可靠性进行了仿真验证。结果表明在确保原有效性和相同误码率前提下, STBC-SM级联编码的可靠性较SM提高了5~8 dB,在确保原可靠性的前提下, STBC-SM级联编码的有效性较STBC提高了。表明文中设计的级联编码可有效的解决通信系统中有效性与可靠性的矛盾问题, 为研究室内可见光MIMO通信提供了很好的理论意义。

The space-time block coding (STBC) has the property of diversity gain in the visible light multiple-input multiple-output (MIMO) communications. However, its validity is low. And the spectrum efficiency is improved in the spatial modulation (SM) coding while the reliability was poor. Therefore, based on the advantages of STBC and SM coding, a STBC-SM concatenated coding was investigated in the visible light MIMO communications. A visible light indoor transmission channel model was established as Lambertian light attenuated. The validity and reliability of the system was verified. Simulation results indicate that the reliability of the STBC-SM concatenated coding is 5-8 dB more than SM under the precondition of ensuring the original validity and the same error rate, and on the premise of ensuring the original reliability, the efficiency of STBC-SM concatenated coding is higher than that of STBC. It shows that the concatenaed codes designed in this paper can effectively settle the contradiction between validity and reliability in the communication system, and has a good theoretical significance for researching indoor visible MIMO communication.