空间激光通信网络中的全光数据合路技术研究

针对空间激光通信网络接入节点多路激光链路传输需求，基于高非线性光纤中四波混频参量效应，并结合色散控制，开展全光合路处理技术研究。采用VPI 10.0模拟平台构建了时间透镜全光合路系统，验证了4路速率为10 Gbps的差分相移键控DPSK（Differential Phase Shift Keying）信号光以及通断键控调制OOK（On-Off Keying）和DPSK混合制式信号光的全光合路可行性，并对全光合路技术实现中色散、光功率等关键参数对系统性能的影响进行了分析，为实际系统的设计和应用提供数据支撑。所提出的全光合路技术具有数据处理带宽大、通信制式兼容且系统复杂度低等优点，可有效降低空间激光通信网络的资源需求与载荷成本，为下一代空间激光骨干网的发展与全面应用提供有效技术支撑。     

Review on residual stress and its effects on manufacturing of aluminium alloy structural panels with typical multi-processes

In the aerospace industry, integrated aluminium alloy plates and stiffened panels with high accuracy and performance attract significant interest. To manufacture these panels as integrity with high accuracy, multiple processes need to be utilised, such as machining, welding and forming. During the whole manufacturing chain, residual stresses can be generated and redistributed in the components among different processes. The residual stress would significantly affect the shapes and properties of the final products. Currently, these great effects are not well considered in the design and manufacturing processes. This paper aims to draw a general understanding of the residual stress generated in the pre-manufacturing processes and its effects on subsequent manufacturing processes. The mechanisms and distributions of residual stresses generated in typical pre-manufacturing processes of structural panels, including machining, welding and additive manufacturing (AM), are firstly summarised. The detailed effects of generated residual stresses on distortion and application properties in subsequent manufacturing processes are then concluded. In addition, current methods developed for the investigation of residual stress effect in multi-processes manufacturing are critically reviewed, including experimental, analytical, finite element (FE) and machine learning methods. Furthermore, the future development trend of methods for residual stress consideration and control in the design of manufacturing processes is summarised, providing comprehensive guidance to achieve the high accurate manufacturing of aluminium alloy structural components.