US Patent 7348892 Pipe mounted telemetry receiver

Methods and apparatus for receiving a telemetry signal with a receiver that is moveably disposed within a drillstring. In certain embodiments, the system comprises a surface module coupled to the upper end of a drillstring, an upper module detachably connected to the surface module, and a lower module moveably disposed within the drillstring. The lower module is coupled to the upper module by an extendable cable. A telemetry signal receiver is disposed on said lower module, which also includes a tractor assembly for moving the lower module through the drillstring.