摘要 |
A method for downhole communication and an apparatus for remote actuation of a downhole tool is disclosed. The method comprises the steps of: programming at least one tag (20) to emit a radio frequency identification signal in the form of a frequency change in a carrier wave; locating a reader (10) responsive to signals emitted from the at least one tag downhole; moving the at least one tag (20) past the downhole reader (10) such that the downhole reader (10) is capable of reading data from the tag (20) when the tag (20) passes the reader (10); and thereby communicating data from the tag (20) to the reader (10) downhole. Typically, the method includes programming the tag (20) and the reader (10) to communicate data by at least one of the following means: transitions between discrete frequencies; use of specific discrete frequencies; and length of time in which a carrier wave emits a specific frequency in preference to at least one other frequency. |