Wireless electromagnetic data communication for downhole use

Flexible smart well solutions for oil wells are limited due to a lack of available systems for wireless data communication. To obtain fully autonomous control and monitoring units downhole, power will have to be generated on the spot and power efficient w ireless communication is critical. A substantial amount of work has been done on systems for Measurement While Drilling using the drill string as waveguide for acoustic or electromagnetic signals. Wireless communication from the reservoir sections of pro ducing wells has received much less attention. Electromagnetic transmission (EMT) based on extremely low frequent (ELF) signaling along the well casing have an interesting potential for wireless communication in producing wells. Most of the work done on EMT has, however, also been oriented towards MWD where power availability is a minor problem. This work has demonstrated the importance of the formation properties which is not fully understood. The work proposed will be concentrated around modeling the influence of realistic local formation properties and completion details. Methods to improve signal transfer to the casing and reduce the signal attenuation will be in focus. Downhole power generation based on ideas from a recent SINTEF-patent, will be ad dressed. Better electronic solutions based on SINTEF's family of high temperature application specific integrated circuits (HTASIC) are critical to meet the main objective. This enables compact designs with higher useful receiver sensitivity and longer co mmunication distances. The technology also ensures longer operational life of the electronics in the well.