For the time-space-frequency varying shallow water acoustic channel, we designed a multi-carrier FH-MFSK system, so that it can be reliably transmitted over these channels. This paper also design of a wake-up signal, and synchronization obtain information frame structure, the simulation result of the algorithm is presented. In the core of DSPC6747 chip, with class D power amplifier, we designed a reasonable layout, stable and reliable hardware circuit. By simulation, adding noise experiments, and water pool experiments verify the good performance of the system, a very low bit error rate (BER) communications were archived.

Due to the high mobility, a wide range of monitoring, air mobile platform-based vehicle detection and tracking system is becoming core of the investigation and the monitoring. Self-motion of the camera and external interference caused by the low-level platform led to instability of the obtained video and affect the correct detection of moving targets and subsequent analysis. For the characteristics for low-level video, an image stabilization algorithm based on SURF combined with normal vector of optical flow is proposed to solve moving vehicle detection low-altitude video. From the experimental results can be seen: (1) compared to other moving vehicle detection methods, the method proposed can get better detection efficiency and detection accuracy; (2) in the complex context, this method can effectively detect moving vehicles. The experiments show that this method has some theoretical and application value of space-based video moving target detection.