| 摘要 |
A method and related apparatus for telemetry between downhole devices and surface devices generate a signal. The apparatus may send a first datum of a first parameter in an uncompressed form (35) and send a second datum of the first parameter in compressed form (38). Delta value compression is the preferred method. Additionally a plurality of lists may be sent to the surface from the downhole device, each list comprising data of a parameter. Each list may additionally comprise a counter value, that identifies each of the samples in the list in relation to the first datum (possibly in a previous list). Surface equipment, knowing the start time of the data, the periodicity of the samples, and a sample number for each datum, may thus calculate a time tag or stamp for each datum. The list containing the time tag may be sent before, during or after the bulk of the data. |
