论文部分内容阅读
在空间相干光通信应用中,针对传统激光器线宽较宽、相位噪声大、易导致锁相环路失锁的问题,研制了单频Nd:YAG非平面环形(NPRO)激光器,其线宽小于1 k Hz,相对强度噪声(RIN)低于-150 d B/Hz,具有窄线宽、低噪声的特点。搭建了光锁相环路,在信号光功率-67 d Bm的情况下实现了两台NPRO激光器的相位锁定。在此基础上开展了信号频率为10 MHz和1.25 GHz的模拟通信实验,在信号光功率分别为-60 d Bm和-53 d Bm时可观测到较理想的眼图。在2.5 Gbps数字通信实验中,接收灵敏度达到-50 d Bm,此时误码率为3.2×10-6。系统灵敏度可接近量子极限,明显优于传统的IM/DD方式,是一种适合长距离、大容量传输的空间通信方式。
In the applications of spatially coherent optical communication, a single-frequency Nd: YAG non-planar ring (NPRO) laser with a wide linewidth and a large phase noise is designed to overcome the problem of the traditional phase-locked loop 1 k Hz, Relative Intensity Noise (RIN) below -150 d B / Hz, narrow linewidth, low noise. An optical phase-locked loop was built to phase lock two NPRO lasers at a signal power of -67 dBm. On this basis, the experiment of analog communication with signal frequency of 10 MHz and 1.25 GHz was carried out, and the ideal eye diagram was observed when the signal light power was -60 d Bm and -53 d Bm respectively. In 2.5 Gbps digital communication experiment, the receiving sensitivity reaches -50 d Bm, the bit error rate is 3.2 × 10-6. System sensitivity close to the quantum limit, significantly better than the traditional IM / DD mode, is a suitable long-distance, high-capacity transmission of space communication.