Patent ID: 6459654
Filing Date: 2002-10-01
Classification: G01V

Abstract:
A transmission method for connecting together, by means of transmission channels, elements of a seismic device comprising local seismic data acquisition, processing and transmission units (RTU), a central control and recording station (CCU) and at least one local control and concentration station (RRS), the elements of the device being provided with multitask control sets, the method allowing precise synchronization of local units (RTU) with a reference signal (TB) emitted by central station (CCU), characterized in that it comprises:using a transmission network (L, RFi) for interconnecting the central station and at least one terminal station, previous measurement of the data transit time on the transmission channels between central station (CCU) and acquisition units (RTU), pretriggering acquisition of the seismic data by acquisition units (RTU), the holding time interval in relation to the time of reception of reference signal (TB) being fixed and greater than the transit time, and applying to reference signal (TB) in the terminal station an adjusted compensation delay taking account of the effective transfer time fluctuations linked with its passage through the multitask control means of said terminal station and the transmission network in order to respect said holding time interval, this delay being adjusted according to the effective rate of each transmission channel of said network.