Digital mud pulse telemetry system.

摘要

A mud pulse telemetry system (10) for use as part of a measuring-while-drilling system comprises an uplink transmitter (18) including a multi-level encoder (34) and a continuous-value mud pulse transmitter (30); and a receiver (22) including a multi-level decoder (36). A downlink system can also be provided comprising a transmitter (24). The uplink and downlink signals can be frequency multiplexed for concurrent transmission. <IMAGE>