SUBSURFACE VERTICAL ANTENNA Russian patent published in 2008 - IPC H01Q1/04 

FIELD: antenna engineering; nondirectional transmitting antennas operating in low-frequency band.

SUBSTANCE: proposed subsurface vertical antenna has vertical conductor installed in borehole made in earth. Metal cylinder is installed in borehole coaxially to vertical conductor. Bases of vertical conductor and metal cylinder are electrically connected to counterpoise made of conductors radially diverging from center of borehole bottom. In addition, shunt conductors are installed within metal cylinder and their top ends are connected at interval p to vertical conductor. Bottom ends of shunt conductor are passed through metal cylinder holes and connected to respective outputs of subband switching unit whose input is connected to coaxial feeder.

EFFECT: enhanced gain.

5 cl, 7 dwg