Synchronous ultra-wide band wireless sensors networks for oil and gas exploration

The fluctuations of the price of crude oil is pushing the oil companies to increase the investments in seismic exploration of new oil and gas reservoir. Seismic exploration requires a large number (500 divide 2000 nodes/sqkm) of sensors (geophones or accelerometers) to be deployed in outdoor over large areas (ges 20 sqkm) to measure backscattered wave fields. A storage/processing unit (sink node) collects the measurements from all the geophones to obtain an image of the sub-surface in real-time. Current connectivity is cable based and requires hundreds of kilometers of cabling causing delays, high logistic costs and low imaging quality. This paper serves as a tutorial to introduce the basic principles of seismic acquisition systems from a wireless communication perspective and provides a number of requirements/specifications for the physical, MAC and network layer to develop wireless sensors networks tailored for oil (and gas) exploration. The wireless geophone network (WGN) system will replace the actual cabled systems used in on-shore seismic acquisition. Oil companies are currently pushing for wireless solutions. Early results suggested that a fully WiFi network does not satisfy all the requirements. This motivates the use of a mixture of technologies. In the proposed system wireless UWB devices/sensors are simultaneously sensing, self-localizing and synchronizing while delivering data to gateway devices in mesh mode. Gateways forward the aggregated traffic to storage unit over long range.