Method of enhancing on-board state estimation using communication signals

摘要

A method of enhancing on-board state estimation for a spacecraft utilizes a network of assets to include planetary-based assets and space-based assets. Communication signals transmitted from each of the assets into space are defined by a common protocol. Data is embedded in each communication signal transmitted by the assets. The data includes a time-of-transmission for a corresponding one of the communication signals and a position of a corresponding one of the assets at the time-of-transmission. A spacecraft is equipped to receive the communication signals, has a clock synchronized to the space-wide time reference frame, and has a processor programmed to generate state estimates of the spacecraft. Using its processor, the spacecraft determines a one-dimensional range from itself to at least one of the assets and then updates its state estimates using each one-dimensional range.

主权项

1. A method of enhancing on-board state estimation for space-based assets, comprising the steps of:
providing a network of assets to include planetary-based assets and space-based assets; transmitting communication signals from each of said assets into space, each of said communication signals defined by a common protocol; embedding data in each of said communication signals transmitted by each of said assets, said data including a time-of-transmission for a corresponding one of said communication signals and a position of a corresponding one of said assets at said time-of-transmission, each said time-of-transmission being synchronized to a space-wide time reference frame, each said position defined in terms of a space-wide location reference frame; providing a spacecraft equipped to receive said communication signals and transmit own-spacecraft communication signals into space, said spacecraft having a clock synchronized to said space-wide time reference frame and having a processor programmed to generate state estimates of said spacecraft; determining, using said processor, one-dimensional range from said spacecraft to at least one of said assets, said step of determining using said data from said communication signals transmitted by said at least one of said assets; updating, using said processor, said state estimates using each said one-dimensional range, wherein an updated state estimate is generated, and wherein said updated state estimate includes an updated position for said spacecraft; embedding, in one of said own-spacecraft communication signals, said updated position for said spacecraft and a current time-of-transmission from said clock; and transmitting, from said spacecraft, said one of said own-spacecraft communication signals wherein said updated position and said current time-of-transmission are available for use by said assets in updating said position thereof used in said step of embedding data.