清华赴美女留学生破解北斗卫星信号：在美获奖

2008年度早期成就奖 获得者：格蕾丝博士（高杏欣?）

表 彰：其对了解和掌握伽利略及北斗等新卫星信号所作出的贡献格蕾丝博士（高杏欣?）已经在卫星导航领域做出了非常值得一提的贡献。她的研究专注于新型全球导航卫星系统所使用的信号及其接收机。格蕾丝是首个破解伽利略试验卫星和北斗一代地球中轨道卫星所使用的编码规则的人。2005年10月，欧洲人发射了伽利略系统的首颗试验卫星，即GIOVE-A。该卫星的信号于2006年1月被激活。在几个小时之内，格蕾丝与实验室里的其它工作人员一道捕捉到了三个波段上的新民用信号。在接下来的几周里，格蕾丝独立工作，破解了GIOVE-A用于生成编码的底层算法，并对其三个波段上所使用的频率进行了解码。她的成果作在2006年5-6月份的《Inside GNSS》封面故事“新一代全球卫星导航系统信号的愿景与全貌”中被刊发。在此之后不久，全世界的接收机公司都使用她的编码来制造原型接收机以获取和跟踪伽利略卫星的信号。

2007年4月，中国发射了属于其北斗一号系统的首颗地球中轨道卫星。在其先前取得成功的技术基础上，格蕾丝解调了这颗M1卫星上所有民用码广播的三个波段频率（E2,E5b,E6），证实了所有的北斗-M1编码都是Gold码，并且破解出其编码生成器为线性移位反馈寄存器。她还将这些伪随机数码应用于一个软件接收机中获取并跟踪北斗-M1卫星。

2008年4月，欧洲人发射了GIOVE-B，即伽利略系统的另一枚试验用原型卫星。格蕾丝又在第一时间破解了其底层编码生成器。 格蕾丝于2008年9月在斯坦福大学取得博士学位。之后她继续从事斯坦福研究项目中有关卫星导航系统的研究，联邦航空局资助了这一项目。她已经在各类会议上提交并发表了16篇高质量的论文。她是2007年国际导航技术大会的资助学生，在这届大会上，她的论文赢得了该届大会的最佳论文奖。

2008.cfm 008 Early Achievement Award Recipient: Dr. Grace Xingxin Gao Citation: For contributions to the understanding and performance of the new satellite signals from Galileo and Compass. Dr. Grace Xingxin Gao has already made truly remarkable contributions to satellite navigation. Her research is dedicated to the signals and receivers used by the new Global Navigation Satellite Systems. Grace was the first to derive the code generators used by the Galileo validation satellites and the first Compass satellite in medium earth orbit. In December 2005, the Europeans launched the first prototype satellite for Galileo, called GIOVE-A . The navigation signals were turned on in January of 2006. Within hours, Grace worked with others in the laboratory to capture the new civil signals in three bands. Within weeks, Grace working independently, derived the underlying algorithms that generate the codes used by GIOVE-A and decoded the codes in all three frequency bands. Her work was published as part of the Inside GNSS cover story “GNSS Album: Images and Spectral Signatures of the New GNSS Signals,” that appeared in May-June 2006. Soon after her publication, receiver companies around the world implemented her codes and built prototype receivers to acquire and track the Galileo satellite. In April 2007, China launched the first medium earth orbiting satellite that belongs to their Compass system. Using her proven techniques, Grace demodulated the civil codes broadcast by this M1 satellite in all three frequency bands (E2, E5b & E6), and proved that all Compass-M1 codes are Gold codes and derived their code generators as linear shift feedback registers. She also applied these PRN codes in a software receiver to acquire and track the Compass-M1 satellite. In April 2008, the Europeans launched GIOVE-B, which is a pre-production prototype satellite for Galileo. Grace was the first to discover the underlying code generators. Grace received her doctorate from Stanford University in September 2008. She continues to work on the satellite navigation systems as part of a Stanford research program funded by the FAA. She has presented and published 16 high quality papers at conferences. In 2007, she was an ION GNSS sponsored student where her paper won the Best Presentation of the Session.