星载GNSS-R海面风场观测载荷关键技术设计与验证

目前海面风场观测手段有限,基于全球导航卫星系统反射信号处理(global navigation satellite system reflection,GNSS-R)的天基观测为全球风场信息获取提供了全新的手段.GNSS-R海面风速探测技术具有全天时、全天候、低功耗、宽覆盖、多信号源、低成本等特点,日益获得了广泛的关注...

Design and verification of key technologies for space-borne GNSS-R sea wind field observation payload

At present, the sea surface wind field observation methods are limited. The space-based observation in view of global navigation satellite system-reflection (GNSS-R) provides a new approach for global wind field sensing. The GNSS-R sea surface wind speed sensing technology has the characteristics of all weather, low power consumption, wide coverage, multiple signal sources and low cost, which has gained widespread attention gradually. Since the designed GNSS system primitively aimed to provide global users with passive navigation services based on radio pseudo-range measurement, and not designed as a space-based remote sensing radiation source, the GNSS-R reflected signal had the cheracteristics such as scattered observation points, weak signal power and signal processing algorithm with large amount of calculations. Taking the BF-1 satellite as the research object, the GNSS-R signal processing algorithm and system were studied. In view of the characteristics of GNSS-R signal, the requirements and constraints of space-borne real-time processing, it was proposed to combine the dynamic phase compensation technology on the short-term cycle correlation and rotation transform to reduce the GNSS-R signal processing burden without distortion. The computational burden of the proposed algorithm was 1/8.99 of the one for the traditional circular correlation method, meanwhile a FPGA based GNSS-R signal processing system was designed. The pay load was tested on the ground and in orbit. The results show that the GNSS-R signal processing system and the proposed signal processing algorithm meet the satellite’s requirements (5-frame per second). The DDM results have be used in the wind field inversion effectively.