通讯槽对电磁波传播随钻测量信号的影响

Influence of communication slots on signal of electromagnetic propagation measurement while drilling

采用径向成层介质的Green函数分析天线屏蔽罩上通讯槽的长度、数目等参数对电磁波传播随钻测量信号的影响规律。结果表明:增加通讯槽的长度和数目可降低电磁信号的衰减,但当这些参数增加到一定数值后信号的衰减不再明显变化;一般取通讯槽的长度约0.1 m、数目在20个以内即可满足工程实际需要;当填充材料的电导率较低时,其引起的电磁信号衰减可忽略不计。

The Green s function in radially stratified media was used to analyze the influence of parameters such as the length and number of communication slots on the signal of electromagnetic propagation measurement while drilling（MWD）.The results show that the electromagnetic attenuation can be reduced by increasing the length and number of communication slots,but the change of attenuation will be indistinct after these parameters have reached to some value.Generally the length is chosen as 0.1m and the number is chosen less than 20,which can satisfy the engineering need.And the electromagnetic attenuation caused by the packing material can be neglected if its conductivity is low.