An improved Dijkstras shortest path algorithm based on search strategy is proposed in this paper. In order to solve the defects of the conventional algorithm, such as large redundancy of space and time, the proposed algorithm introduces a constraint function with weighted valueωfor searching each position in the state space to guide the search forward to expected direction. Meanwhile, according to different complexity of map information, the weighted valueωcan be flexibly changed to make the constraint function more reasonable to effectively improve the search efficiency. Experimental result shows that the number of nodes on search path and computation time is obviously reduced, and the improved algorithm can be fast to search out the goal nodes.

As demand for data rate continues to increase, new problem of LVDS start to come out, such as signal integrity. Those problems are primarily caused by frequency-dependent loss in transmission line. The purpose of pre-emphasis is to apply intentional overdriving to the signal and get it back to the original signal with the proper weight, thereby compensating for the ISI from the nearby data symbol. In order to avoid over-emphasis we propose a programmable pre-emphasis adapting to different situation, and finish the prototype which can improve the transmission bandwidth more effectively, achieving high-speed data transmission.

The paper proposes an improved genetic algorithm which is applied to the problem of GPS signal acquisition.The improved genetic algorithm uses the small section method of the initial population, dynamic search range of parameter, and the adaptive crossover probability and mutation probability to search GPS signal parameters. Simulations and experiment results show that the improved genetic algorithm can search the signal parameters rapidly and precisely. The GPS signal acquisition performance is improved.

In order to improve acquisition speed and carrier frequency accuracy, a fast algorithm to acquire GPS signal is proposed. Signal-to-Noise Ratio is improved by coherent integration and non-coherent integration. The advantages of serial sliding algorithm and circular correlation algorithm are combined to achieve high carrier frequency accuracy. Removing the information of C/A code makes serial search from two-dimensional to one-dimensional to achieve less computation. Simulation shows weak signal of-30dB S/N is successfully acquired. The error of carrier frequency is controlled within 50Hz. So the data processing efficiency for the tracking loop is greatly increased.

In order to solve the problem of GPS signal acquisition, an acquisition algorithm based on an improved genetic algorithm (IGA) is proposed in this paper. The IGA employs the technologies including the dynamic search range of parameter, the adaptive probabilities of crossover and mutation, and the small section method for generation of an initial population to search Doppler shift and code phase. Simulations and experiment results show that the proposed method can acquire the signal parameters precisely and rapidly. Consequently, the acquisition performance is improved.