Laser diodes (LDs) are widely used in optical wireless communication (OWC) and optical networks, and proper theoretical models are needed to precisely describe the complicated beam field of LDs. A novel mathematical model is proposed to describe the vectorial field of nonparaxial LD beams. Laser beam propagation is studied using the vector Rayleigh diffraction integrals, and the stationary phase method is used to find the asymptotic expansion of diffraction integral. The far-field distribution of the LD beam in the plane parallel and perpendicular to the junction is considered in detail, and the computed intensity distributions of the theory are compared with the corresponding measurements. This model is precise for single transverse model beam of LDs and can be applied to describe the LD beams in OWC and optical networks.

中文翻译：

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光通信中大功率激光二极管光束的矢量瑞利衍射

激光二极管（LD）广泛用于光学无线通信（OWC）和光网络中，需要适当的理论模型来精确描述LD的复杂光束场。提出了一种新颖的数学模型来描述非傍轴LD光束的矢量场。利用矢量瑞利衍射积分研究了激光束的传播，并采用固定相方法求出了衍射积分的渐近展开。详细考虑了LD光束在平行和垂直于结的平面中的远场分布，并将计算出的理论强度分布与相应的测量结果进行了比较。该模型对于LD的单个横向模型光束非常精确，可用于描述OWC和光学网络中的LD光束。