The invention relates to the technical field of oil and gas
well drilling measurement and the technical field of underground
information transmission, in particular to a cased well near-window
coupling electromagnetic wave
measurement while drilling method which comprises the steps that S1, a composite medium
equivalent model is established offline; s2, according to the composite medium
equivalent model, scanning and determining a near-window optimal interval; s3, generating a typical impedance interval and a near window parameter set according to the near window optimal interval; S4, matching the typical impedance interval on line, and judging the typical impedance interval as a near window transition section according to characteristics; s5, triggering a near window mode and closed-loop
fine tuning at a near window transition section; and S6, according to the protection rule, carrying out safe degradation and outputting a result. According to the method, the multi-layer medium model is established through the well-following measurement method, and the near-window
coupling interval is calculated according to the model, so that the
signal transmission stability of the insulating short section in the well-following measurement process is improved, short-distance stable chain establishment in a casing window is realized, the problem of underground touch
typing is solved, and the electromagnetic performance reliability is improved.