A Practical Field Experiment of Multiple Transmission Resistivity Profiling Using Code Division Multiple Access

We have conducted field experiments for evaluating practicality of a multiple transmission DC resistivity profiling using Code Division Multiple Access (CDMA) technique. In a multi-transmission resistivity profiling, it is possible to inject current at multiple points simultaneously by using coded current waveforms among which covariance between mutual waveforms equal to zero. Multi-transmission resistivity profiling technique has the potential to enable very rapid measurement compared to mono-transmission conventional resistivity profiling. In this paper, we have conducted experiments for evaluating workability and noise-robustness. The results of field experiments show that the efficiency of a multi-transmission resistivity measurement is quite high regarding to current duration time. We have found that erratic low-frequency noise badly affects the measurement result but it was possible to improve this result by post-processing the measured potential waveform.