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在单次散射条件下,研究了非视线紫外光散射通信系统的信道特性。分析了传输损耗与光源发散角、接收视场和收发仰角等系统几何参数之间的关系,结果表明传输损耗随收发仰角的增大而增大,增加接收视场可以降低损耗;针对两种不同情况讨论了损耗随光源发散角的变化关系,发现发散角对损耗的影响较小,可根据应用场合适当确定.研究了信道的多径传输现象及其对系统性能的影响,结果表明多径传输引起的脉冲展宽将导致码间干扰的产生,限制系统的通信速率,并定量讨论了 NRZ 码和 RZ 码两种情况下码间干扰的影响,发现相对于 NRZ 码,采用 RZ 码可以有效地减轻码间干扰,获得更高的通信速率.
Under single-scattering conditions, the channel characteristics of non-line-of-sight UV light scattering communication systems are studied. The relationship between the transmission loss and the geometric parameters of the system such as the divergence angle of the light source, the receiving field of view and the transmitting / receiving elevation angle is analyzed. The results show that the transmission loss increases with the elevation of the transmitting / receiving angle and the receiving field of view can reduce the loss. The relationship between the loss and the divergence angle of the light source is discussed in detail, and it is found that the divergence angle has a small influence on the loss and can be appropriately determined according to the application occasion. The multi-path transmission phenomenon of the channel and its influence on the system performance are studied. The pulse broadening will lead to intersymbol interference and limit the communication speed of the system. The influence of intersymbol interference on NRZ codes and RZ codes is discussed quantitatively. It is found that using RZ codes can reduce the effect of NRZ code effectively. Inter-symbol interference, access to higher communication rates.