针对水下无线光通信系统中无法兼顾聚光效率和光斑均匀性的问题，文章设计了一种复合折反式接收天线。仿真结果表明，传统的菲涅尔透镜聚光效率只有58.725%，而新设计的复合折反式接收天线聚光效率达到86.557%。在保证高聚光效率的情况下，光斑的均匀性也较好，均匀度为0.659 3。随后分析了平行光源在不同角度入射时聚光效率和光斑位置偏移的变化，发现菲涅尔透镜在入射角为2°时聚光效率就只有3.582 2%；而文章所设计的复合折反式接收天线在入射角度为1.5 °时，聚光效率仍可以达到50%以上，入射角度在4 °时仍能检测到光斑。文章设计的接收天线在水下远距离无线激光通信系统中有很好的接收效果，该接收天线适用于高增益和小视场的水下无线激光通信环境。

Aiming at the problem that the concentrating efficiency and spot uniformity cannot be taken into account in underwater wireless optical communication system, a composite refractive receiving antenna is designed in this paper. The simulation results show that the concentrating efficiency of the traditional Fresnel lens is only 58.725%, while that of the newly designed composite refractive antenna is 86.557%. Moreover, the uniformity of the spot is also good, with the uniformity of 0.659 3 under the condition of ensuring high concentration efficiency. Then the change of focusing efficiency and spot position offset of parallel light source at different incident angles is analyzed. It is found that the focusing efficiency of Fresnel lens is only 3.582 2% at 2 °incident angle, while the focus efficiency of the composite refractive antenna designed in this paper can still reach more than 50% when the incident angle is 1.5 °, and the spot can still be observed when the incident angle is 4 °. The receiving antenna designed in this paper has good reception effect in underwater long-distance wireless laser communication system. Therefore, the receiving antenna designed in this paper is suitable for underwater wireless laser communication environment with high gain and small field of view.