应用于空间光通信的锥形光纤阵列

Tapered fiber array for free space optical communication

空间光到光纤的耦合是自由空间光通信的关键技术,针对光纤纤芯直径很小,给耦合带来很大困难这一问题,文章先分析了空间光到单光纤的耦合模型,然后提出了采用锥形光纤阵列提高耦合效率的接收方法,之后,在实验室试制了锥形光纤阵列样品,并在微振动环境下采用两种方法测量接收光功率,第一种方法是采用一个大靶面雪崩光电二极管(APD)同时接收九根光纤光功率,第二种方法是采用熔融拉锥型光分路器将9根光纤中的光合并进入一根光纤,然后用光功率计进行测量,测量结果表明,采用第一种方法比第二种方法得到的光功率稍高,这是因为熔融拉锥后的光纤会有能量泄露。从总体上看,两种接收方法均说明锥形光纤阵列样品达到了预期的接收效果。

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 difficulties to coupling.In order to improve the coupling efficiency,we analyze the coupling model of space light to a single fiber,and then put forward a new receiving method which adopts a conical fiber array as receiver.After that,the sample of conical fiber array is fabricated in the laboratory,and the test experiment in micro-vibration environment is carried out,in which two methods are used to measure the received optical power.In the first method,a large target avalanche photodiode(APD)is used to receive the optical power of nine fibers simultaneously.In the second method,the light in nine fibers is merged into one with the optical splitter,and then the optical power is measured with an optical power meter.The measurement results show that the optical power measured with the first method is higher,because the energy leakage would exist in the merged fiber.On the whole,the results of two receiving methods indicate that the sample can meet the desired requirements.