物理学报2016，Vol.65Issue(8)：084207-1-084207-8,8.DOI:10.7498/aps.65.084207
混沌与湍流大气中的光通信∗
Optical communication in turbid and turbulent atmosphere
摘要
Abstract
Free space optical-communication (FSO) has gained significant importance due to its unique features: large band-width, license free spectrum, high data rate, easy and quick deployability, less power and low mass requirement. However, the performance of FSO is degraded in the turbid and turbulent atmosphere, dramatically. Various techniques are pro-posed to cope with the turbid media and turbulence in atmosphere, e. g. aperture averaging, diversity, adaptive optics, modulation and coding and orbital angular momentum. However, in the above systems with point-to-point optical communication structure, there exist obvious drawbacks or they are complex and expensive, and thus difficult to use in practice. In this article, array-to-point optical communication (APOC) with good performance in turbid and turbulent atmosphere is demonstrated. The strongly disturbed communication channel can be expressed as a circular complex Gaussian transmission matrix, and the transmitted field is described as a linear combination of the fields coming from different and independent segments of the digital micro-mirror device (DMD), so that the cross terms are averaged on the surface of bucket detector. Instead, the contributions of all segments for each light field nearly becomes equally weighted. Turbulence and other noises are reduced for the incoherence with sampling matrix based on the second-order correlation which has widely been used in ghost imaging and LIDAR. Consequently, narrow-band optical filter is not required at the receiver. The decoding algorithm is a new signal processing strategy from information technology, compressed sensing, which discards low frequency components in sampling process and recovers the signal by conducting convex optimization. Numerical simulations and experiments with binary and multi-bits level signals are demonstrated to show that the bit error rate of the proposed method APOC is approximately 10−4–10−2, which is feasible for the optical communication in such complex communication channels. The communication rate, limited by the frequency of the DMD and the sampling rate of the receiver, could reach hundreds of kbit/s, and with improved technology a rate of Mbit/s should be attainable. This proposed APOC could realize optical communication in turbid and turbulent atmosphere and thus offers a very effective approach to promoting the implementation in military and rescue.关键词
光无线通信/混沌介质/二阶关联/压缩感知Key words
optical communication/turbid media/second-order correlation/compressed sensing引用本文复制引用
冒添逸,陈钱,何伟基,庄佳衍,邹云浩,戴慧东,顾国华..混沌与湍流大气中的光通信∗[J].物理学报,2016,65(8):084207-1-084207-8,8.基金项目
国家自然科学基金(批准号:61271332,61101196)资助的课题.* Project supported by the National Natural Science Foundation of China (Grant Nos.61271332,61101196) （批准号:61271332,61101196）
