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Scattering deflects the ultraviolet ray, and makes it possible to bypass the obstacles between two blocked nodes. To
investigate the channel characteristics of this kind of link, models have been developed, and most of them are based on
coplanar geometry. Non-coplanar geometry, however, is unavoidable in most actual application. To make sure the
influences of this factor, a universal model which describes the channel characteristics of Non-Line-Of-Sight (NLOS)
Ultraviolet communication for non-coplanar geometry is developed in this paper. On the basis of classical single-scatter
model, this model mainly estimates the impulse response and the pass loss with the transmitter and the receiver cone
pointed in arbitrary directions.
There are three major contributions in the paper. Firstly, classical single-scatter model and the differences effective
scattering volume between coplanar geometry and non-coplanar geometry were described. Trigonometry and
optimization techniques were proposed to overcome the restriction that the transmitter and the receiver cone axes lie in
the same plane; secondly, a Monte-Carlo (MC) model was constructed to verify the single scatter model; finally
numerical simulations and analysis were presented.
Numerical simulation shows that the deflection of the transmission or the reception cones(α, α) decreases the
signal, this decrease is slight under small deflection, and becomes more serious as deflection increases, finally
remarkable when the deflection reaches a threshold. The result shows that a positive correlation exists between the
threshold and the source divergence, which means that large source divergence gives better tolerability of the off-axis
angle, but worse pulse width. In addition, the influence of deflection can be reduced signally by deflecting the two
cones in the same side.MC model draws the similar conclusion approximately. Compared with other models, this model
releases the restriction that the transmitter and the receiver cone axes lie in the same plane, which making it more
versatile.
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