LEI Zhi-yuan1,2,3, GUO Ji1, LU Xiao-chun1,3
1. National Time Service Center, Chinese Academy of Sciences, Xi′an 710600, China;
2. Key Laboratory for Precision Navigation and Timing Technology, National Time Service Center,
Chinese Academy of Sciences, Xi′an 710600, China;
3. Graduate University of Chinese Academy of Sciences, Beijing 100039, China
Abstract: In order to understand the constant envelope AltBOC(alternate binary offset carrier) modulation easily, we first derived 2-codes AltBOC starting with BOC signal and combining with the directly perceived signal phase diagram, then derived 4-codes AltBOC, and at last the expression of constant envelope AltBOC signal was derived as well as some numerical characteristics concerned were given.
Key words: AltBOC; Galileo navigation system; subcarrier; constant envelope