Abstract: Disclosed is a dynamic collision avoidance method for an unmanned surface vessel based on route replanning. The method comprises the following steps: acquiring navigation information and pose information of a neighboring ship of an unmanned vessel itself via a vessel-borne sensor; constructing a collision cone between the unmanned vessel and the neighboring ship; introducing a degree of uncertainty with respect to observing movement information of the neighboring ship and applying a layer of soft constraint to the collision cone; applying a speed and a heading limit range of the unmanned vessel; acquiring an ultimate candidate speed set; introducing a cost function to select an optimum collision avoidance speed; and performing an internal recycle of navigation simulation with the optimum collision avoidance speed to obtain a route replanning point for dynamic collision avoidance of the unmanned vessel.

Abstract: A detection method of nonlinear ultrasonic guided wave with carrier modulation is described. The high and low frequency components are determined according to the frequency response characteristics of the detection object, and the high-frequency components are processed by delay and combined with the low-frequency components to form a carrier modulation signal. The single excitation and single receiving mode are adopted for signal acquisition. The carrier modulation signal with high frequency and low frequency components is excited by a single transducer. The nonlinear modulation effect is produced by the interaction between the carrier signal and the damage, and the signals are collected by the receiving transducer through transmission method. According to the arrival time of high frequency components and the time of end reflection echo, the signal is intercepted and analyzed. After filtering and normalization processing, the received signal is decomposed by empirical mode decomposition (EMD).

Abstract: Disclosed is a dynamic collision avoidance method for an unmanned surface vessel based on route replanning. The method comprises the following steps: acquiring navigation information and pose information of a neighboring ship of an unmanned vessel itself via a vessel-borne sensor; constructing a collision cone between the unmanned vessel and the neighboring ship; introducing a degree of uncertainty with respect to observing movement information of the neighboring ship and applying a layer of soft constraint to the collision cone; applying a speed and a heading limit range of the unmanned vessel; acquiring an ultimate candidate speed set; introducing a cost function to select an optimum collision avoidance speed; and performing an internal recycle of navigation simulation with the optimum collision avoidance speed to obtain a route replanning point for dynamic collision avoidance of the unmanned vessel.

Abstract: An apparatus and a method for monitoring in-band OSNR (Optical Signal-to-Noise Ratio) which monitors the in-band OSNR by using two parallel Mach-Zehnder-interferometers with different optical time delays are disclosed. The apparatus and method can be resistant to chromatic dispersion, polarization mode dispersion and polarized noise, can measure the coherence characteristics of the signal without removing the noise, and can be manufactured into a semiconductor integrated device and be applied in the future high-speed optical network.

Abstract: An apparatus and a method for monitoring in-band OSNR (Optical Signal-to-Noise Ratio) which monitors the in-band OSNR by using two parallel Mach-Zehnder-interferometers with different optical time delays are disclosed. The apparatus and method can be resistant to chromatic dispersion, polarization mode dispersion and polarized noise, can measure the coherence characteristics of the signal without removing the noise, and can be manufactured into a semiconductor integrated device and be applied in the future high-speed optical network.

Abstract: The present invention provides an optical communication method, comprising: performing modulation on the obtained bit stream data to generate modulated signals; performing differential encoding on the modulated signals to generate differentially encoded signals; converting the differentially encoded signals into electrical signals; and mapping the electrical signals onto optical carriers to generate optical signals for transmission. With the present invention, it is possible to enhance the system's capability of resisting inter-carrier interference without decreasing spectrum efficiency, hence improving the tolerance of existing optical communication systems towards laser linewidth, fast-changing PMD, optical fiber nonlinearity, inter-channel interference and other damages, greatly enhancing system performances.

Abstract: The present invention provides an optical communication method, comprising: performing modulation on the obtained bit stream data to generate modulated signals; performing differential encoding on the modulated signals to generate differentially encoded signals; converting the differentially encoded signals into electrical signals; and mapping the electrical signals onto optical carriers to generate optical signals for transmission. With the present invention, it is possible to enhance the system's capability of resisting inter-carrier interference without decreasing spectrum efficiency, hence improving the tolerance of existing optical communication systems towards laser linewidth, fast-changing PMD, optical fiber nonlinearity, inter-channel interference and other damages, greatly enhancing system performances.