A Submillimeter-Level Relative Navigation Technology for Spacecraft Formation Flying in Highly Elliptical Orbit

Abstract

Spacecraft formation flying (SFF) in highly elliptical orbit (HEO) has attracted a great deal of attention in many space exploration applications, while precise guidance, navigation, and control (GNC) technology—especially precise ranging—are the basis of success for such SFF missions. In this paper, we introduce a novel K-band microwave ranging (MWR) equipment for the on-orbit verification of submillimeter-level precise ranging technology in future HEO SFF missions. The ranging technique is a synchronous dual one-way ranging (DOWR) microwave phase accumulation system, which achieved a ranging accuracy of tens of microns in the laboratory environment. The detailed design and development process of the MWR equipment are provided, ranging error sources are analyzed, and relative orbit dynamic models for HEO formation scenes are given with real perturbations considered. Moreover, an adaptive Kalman filter algorithm is introduced for SFF relative navigation design, incorporating process noise uncertainty. The performance of SFF relative navigation while using MWR is tested in a hardware-in-the-loop (HIL) simulation system within a high-precision six degrees of freedom (6-DOF) moving platform. The final range estimation errors from MWR using the adaptive filter were less than 35 μm and 8.5 μm/s for range rate, demonstrating the promising accuracy for future HEO formation mission applications.

Evaluation of Precise Microwave Ranging Technology for Low Earth Orbit Formation Missions with Beidou Time-Synchronize Receiver

“…The composition block diagram of one on-board MWR system equipment can be found in Figure 2 of [ 26 ], not shown here. MWR system is composed of the same ranging equipment on two leader-follower formation satellites, except for the difference of ultra-stable oscillator (USO) frequency of 66Hz.…”

“…In the so-called integrated design, on the one hand, the BeiDou dual frequency receiver needs to share a unified frequency source with the MWR, taking the homologous USO as the frequency reference; on the other hand, it needs to design an integrated hardware platform for the digital processing of the MWR and the receiver, so as to realize the integrated signal processing and eliminate the errors caused by the common channels. The signal processing hardware platform mainly consists of MWR measurement signal processing, BeiDou signal processing, time management unit, and external interfaces [ 26 ].…”

“…The BeiDou dual frequency receiver has been carefully designed and developed that compacted into MWR process module. The receiver prototype photo can be found in Figure 4 of [ 26 ], and Figure 4 illustrate the sketchy receiver block diagram.…”

“…The test of MWR payload is conducted in a precise calibrated six degrees of freedom (6-DOF) moving platform with an accuracy of microns in position and milliarcseconds in attitude orientation, as in Figure 7 of [ 26 ]. Two stages of test work have been performed in laboratory: Stage one ( Section 4.1 ), MWR equipment ranging accuracy assessment, with or without integrated BeiDou dual frequency receiver, and DOWR measurement technique test; and stage two ( Section 4.2 ), close loop hardware-in-loop (HIL) simulation that evaluating the relative navigation performance with MWR payload, aiming towards the future of EGFD and DEM spacecraft formation missions.…”

“…Additionally, with the original observe data obtained, the most forecast reward of EGFD mission is the design and development of submillimeter level accuracy ranging equipment with in-orbit verification, which enables the future application of a precise GNC system for SFF missions in both LEO and HEO scenario [ 26 ]. The K-band MWR payload is particularly designed and deployed for reasons below: Unlike accuracy optical ranging sensors that relies on high precision pointing mechanism [ 22 , 27 ], microwave ranging can be realized by transceiver antenna with a few degrees wide main lobe angle.…”