ABSTRACT
Free space optical communication based on modulating retroreflector uses a modulating retroreflector terminal instead of a traditional communication terminal to build a link. Compared with classical free space optical communication systems, a system based on a cat’s eye modulating retroreflector has great advantages. It can build communication links more rapidly, and its passive terminal is smaller and lighter with a lower power consumption. In this paper, a new cat’s eye modulating retroreflector based on focal plane misalignment is developed. When the focal plane of a cat’s eye lens is misaligned/aligned, the reflection direction of the beam will change. The change will cause the intensity of retro-reflected beam change to achieve intensity modulation. An experimental link was built using a cat’s eye modulating retroreflector which uses a Micro-Electro-Mechanical Systems (MEMS) array with high reflection film placed on the focal plane. The link range is about 1 km, with the highest rate of 10 kbps. The results show that the cat’s eye modulating retroreflector based on focal plane misalignment is available. It could realize amplitude modulation, and the data rate is decided by the switching rate of focal plane.
