The new design of tapered fiber array for space optical receiver

The coupling of space light to optical fiber is the key problem in free space optical communication. The diameter of fiber core is very small, which brings great difficulty to coupling. We first analyze the coupling model, and propose the conical fiber array as a new receiver to improve the efficiency. After that, the sample of conical fiber array is produced in the laboratory, and the testing experiment in micro vibration environment is carried out. In this experiment, two methods are used to measure the received optical power. In the first method, the light from nine fibers is merged into one with the optical splitter. In the second method, a large target avalanche photodiode (APD) is used to receive the light from nine fibers. Compared with our previous work, both measurement methods show the coupling efficiency of the conical fiber array is higher.