A trellis coded pulse interval modulation for measurement while drilling telemetry

Measurement While Drilling (MWD) is a core technology for petroleum exploration. In this paper, a joint convolution code and pulse interval modulation, so called the trellis coded pulse interval modulation (TC-PIM) is proposed. The TC-PIM maximizes the minimal time distance between the modulation output sequences, and compared with the uncoded pulse interval modulation (PIM), it gets significant coding gain about 4dB. The TC-PIM can be used for measurement while drilling system to extend the transmission distance of the mud pulse telemetry system.