自由空间光通信正交频分复用(Free Space Optical-Orthogonal Frequency Division Multiplexing,FSO-OFDM)系统面对的主要问题是峰均比(PAPR)高而导致的信号失真。而选择性映射(Selected Mapping,SLM)算法可以有效解决FSO-OFDM系统中的...自由空间光通信正交频分复用(Free Space Optical-Orthogonal Frequency Division Multiplexing,FSO-OFDM)系统面对的主要问题是峰均比(PAPR)高而导致的信号失真。而选择性映射(Selected Mapping,SLM)算法可以有效解决FSO-OFDM系统中的峰均比问题。目前,对峰均比抑制算法的研究还主要集中在理论方面,而且主要在发端研究降低峰均比的方法,而很少有文献将其应用于实际的信道传输。所以对FSO-OFDM系统中峰均比抑制算法的具体实现,尤其是在接收端进行实际验证的方法就显得意义重大。文中通过仿真信道传输和硬件实验都验证了采用SLM算法后FSO-OFDM系统的抗噪声干扰性能增加,并验证了SLM算法应用于实际的有效性,且该实验结果也为降低PAPR的后续研究奠定了实验基础。展开更多
Free Space Optical (FSO) communication is one of the most promising access methods. But, the different weather conditions will affect the transceiver performance. In this paper, we build a FSO communication system wit...Free Space Optical (FSO) communication is one of the most promising access methods. But, the different weather conditions will affect the transceiver performance. In this paper, we build a FSO communication system with 16-ary phase shift key-orthogonal frequency division multiplexing (16PSK-OFDM) downstream signals. We analyze the transmission performance of 16PSK-OFDM optical signals under five different weather conditions (sunny, light rain, moderate rain, snow, and fog). The optical spectral diagrams, constellation diagrams, and bit error rate (BER) of the received signals are simulation measured and analyzed. The results show that the constellation diagram under sunny condition is clear, and the value of BER is about 10?4.2 after 16PSK-OFDM optical signals pass through 500 m FSO link. Note that, the constellation points are dispersed under the other weather conditions.展开更多
文摘自由空间光通信正交频分复用(Free Space Optical-Orthogonal Frequency Division Multiplexing,FSO-OFDM)系统面对的主要问题是峰均比(PAPR)高而导致的信号失真。而选择性映射(Selected Mapping,SLM)算法可以有效解决FSO-OFDM系统中的峰均比问题。目前,对峰均比抑制算法的研究还主要集中在理论方面,而且主要在发端研究降低峰均比的方法,而很少有文献将其应用于实际的信道传输。所以对FSO-OFDM系统中峰均比抑制算法的具体实现,尤其是在接收端进行实际验证的方法就显得意义重大。文中通过仿真信道传输和硬件实验都验证了采用SLM算法后FSO-OFDM系统的抗噪声干扰性能增加,并验证了SLM算法应用于实际的有效性,且该实验结果也为降低PAPR的后续研究奠定了实验基础。
文摘Free Space Optical (FSO) communication is one of the most promising access methods. But, the different weather conditions will affect the transceiver performance. In this paper, we build a FSO communication system with 16-ary phase shift key-orthogonal frequency division multiplexing (16PSK-OFDM) downstream signals. We analyze the transmission performance of 16PSK-OFDM optical signals under five different weather conditions (sunny, light rain, moderate rain, snow, and fog). The optical spectral diagrams, constellation diagrams, and bit error rate (BER) of the received signals are simulation measured and analyzed. The results show that the constellation diagram under sunny condition is clear, and the value of BER is about 10?4.2 after 16PSK-OFDM optical signals pass through 500 m FSO link. Note that, the constellation points are dispersed under the other weather conditions.