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Satellite signal acquisition is indispensable for signal tracking and solution, and its operating time directly determines the starting speed of the software receiver. The length of Beidou code is twice of Global Positioning System (GPS) C/A code. Therefore, the acquisition time will increase with the traditional algorithm. This paper proposed a fast acquisition algorithm which decomposed the N points Fast Fourier Transform (FFT) to three parts. The algorithm transformed the structure of parallel code phase acquisition algorithm and decomposed the mixed signal and local code into three parts to do FFT operations, and then the correlation results were got by fusion algorithm. In this way, the algorithm did one correlation operation every 3 sampling points and its structure was more flexible. As a result, the amount of calculation was reduced by about 27% and consumption of memory by about 30%. On the other hand, the PTP values of the two algorithms under discussion were very close, indicating their acquisition performances were basically equivalent. In other words, the proposed algorithm can reduce operational time and resource consumption without loss of acquisition accuracy.

Zr55Al10Ni5Cu30 bulk metallic glass was prepared through water-cooled copper mold suction casting, and was rolled up to 95% in thickness reduction. The structures and thermal stabilities of the as-cast and as-rolled specimens were examined by X-ray diffractometer and differential scanning calorimeter. As the thickness reduction increases, the crystallization onset temperature, peak temperature and the apparent activation energy of crystallization almost keep constant, while the glass transition temperature decreases from 681 to 671 K and the apparent activation energy of glass transition increases from (404±26) to (471±29) kJ/mol. The glass transition process is markedly affected by the rolling induced changes of microstructure and structural relaxation.