Downhole transmission system with perforated MCEI segments

A transmission system, comprising:

• a downhole tool comprising an annular groove communicating with a drilled passageway in the downhole tool;
• an annular housing disposed within the annular groove, the annular housing comprising at least first and second perforations;
• an annular magnetically conductive electrically insulating, MCEI, trough disposed within the annular housing, the annular MCEI trough comprising first and second perforations;
• an annular electrically conductive coil laid within the annular MCEI trough;
• the annular electrically conductive coil comprising a groundable end and a transmission end;
• the groundable end being connected to a ground post electrically contacting the downhole tool through the first perforation in the annular housing and the first perforation in the MCEI trough, and wherein
• the transmission end is connected through the second perforation in the annular housing and the second perforation in the MCEI trough to a cable within the drilled passageway in the downhole tool.