Patent ID: 8463467

Claim:
A control device (D), for a spacecraft (Si) of a group of spacecraft intended to move according to a chosen formation, comprising: at least one assembly including an emission/reception antenna (A 1 ) and of two receiving antennas (A 2 , A 3 ) installed at chosen locations on a face of said spacecraft (Si) and able to emit and/or receive radiofrequency signals, processing means (MT) designed to estimate the directions of transmission of the signals emitted by other spacecraft of the group on the basis of said signals received by said antennas (A 1 -A 3 ), each antenna (A 1 -A 3 ) of said assembly is designed to emit and/or receive first and second signals exhibiting first and second chosen frequencies spaced apart by a chosen frequency gap, first measurement means (M 1 ) designed to determine first and second differences in path length between antennas (A 1 -A 3 ), corresponding to the first or second chosen frequencies and to said frequency gap, on the basis of the first and second signals received by each of said antennas of said assembly originating from another spacecraft (Si′) of said group, attitude measurement means (M 2 ) designed to deliver measurements of rotation undergone by said spacecraft (Si), wherein said processing means (MT) are designed to a) coarsely estimate the direction of transmission of the signals emitted by said other spacecraft (Si′) on the basis of first and second initial path length differences, b) order a coarse positioning of said spacecraft (Si) so that a chosen axis (X) of a frame of reference tied to said spacecraft is substantially aligned with respect to said coarsely estimated direction of transmission, c) order at least one chosen rotational turning of said spacecraft (Si) about said chosen axis (X), d) precisely estimate said direction of transmission of the signals emitted by said other spacecraft (Si′) on the basis of the rotation measurement delivered by said attitude measurement means (M 2 ) and of a measurement of variation of the first or second initial path length differences induced by said rotation, performed by said first measurement means (M 1 ).