Research And Design Of Hybrid Communication System For Land Seismic Acquisition Equipments

Nowadays, any economy’s rapid growth and development has to be supported by a lot of energy supply and consumption. In all kinds of energy, oil and gas play the most important role in the development of human society. Therefore, the people’s demand of oil and gas increases everyday. For this reason, current oil and gas explorations are attempting to explore the second deep place and following the trend of “WWH”(wide band, wide azimuth, high density) in seismic data acquisition. The trend has been leading to the quickly increasing scale of seismic exploration. However, some parameters of usual communication system used in seismic exploration, such as portable level, application condition(light-of-sight, or non-light-of-sight), and transmitting ability(maximum communication distance and communication rate) are bottlenecks of the increasing scale, now. Thus, it is very meaningful that designing a communication system for land seismic acquisition equipments, which can be used in complex terrain with portability and strong transmitting capability.Based on the cable telemetry seismograph and the cable-less self-positioning seismograph, which are both researched by Jilin University, we carried out a study on the communication system of land seismic acquisition system by starting with analyzing the problems in practice. As a result, a hybrid communication system for seismic acquisition system is proposed, which is able to be applied in complex terrain, with portability and strong transmitting capability. The communication system is a kind of hierarchical network, which is mainly composed of core network and extended network. Core network, somewhere between control center and extended network, is responsible for bearing the communication load and realizing the long-distance communication. In the 3G or 4G signal cover, core network is composed of 3G or 4G network, where the 3G/4G gateway seismographs, based on ARM and Linux, are used as the connecters between core network and extended network; in the zone without 3G and 4G signal, core network is composed of high-power Wi-Fi technologies and wired Ethernet, where the hybrid cross-stations which are based on Power PC and Linux, with the capability of connecting both cable telemetry seismographs and cable-less self-positioning seismographs, are used as the connecters between core network and extended network. Extended network is at the lowest layer of the hybrid communication system, whose order is to realize cover for complex terrain and eliminate blind zones in seismic acquisition areas by portable communication devices. The multi hop ad hoc network protocol designed in this paper is used in extended networks to accomplish the management and data transmission tasks of each acquisition station, as well as make the network has a certain ability of fault tolerance.It is proved the hybrid communication system is viable, through the tests of performance index and stability. Compared with the similar systems at home and abroad, the hybrid system has advantages of portability, no-blind cover, long-distance communication, high-speed transmission and so on. These advantages make seismic exploration become larger scale and greater efficiency.