Patent ID: 7376045

Claim:
A system for determining relative positions of a plurality of towed marine seismic streamers, comprising: a plurality of acoustic transmitters, mounted inside the streamers, adapted to transmit broadband signals having low cross-correlation between the signals of different transmitters; a plurality of acoustic receivers, mounted inside the streamers, said receivers being adapted to receive the signals transmitted in an in-line direction between transmitters and receivers mounted in the same streamer and to receive signals transmitted in a cross line direction between transmitters and receivers mounted in different streamers; at least one receiver processor adapted to cross-correlate the signals received at the receivers with copies of transmitter signals to determine identities of transmitters of the received signals and travel times of the received signals; and a main processor adapted to convert the travel times to distances between the identified transmitters and the receivers, to determine in-line distances along streamers between transmitters and receivers in the same streamer, and cross line distances between transmitters and receivers in different streamers, to combine the converted distances to form a trilateration network representation of the distances between the transmitters and the receivers, to solve the trilateration network representation to determine the relative positions of the transmitters and the receivers in the streamers, including position changes resulting from stretching of the steamers as well as position changes resulting from movement of the streamers, and to determine relative positions of the streamers from the relative positions of the transmitters and receivers.