Sommerfeld-Goubau is an advancement of the single wire transmission Technology used to conduct radio waves at UHF and Microwave Frequencies developed in the late 1800's to early 1900's.(2,3,4) The dielectric coated transmission line necessary for the intended function, was invented by F. Harms in 1907 and George J. E. Goubau (6) in 1950 (5) based on studies of surface waves on wires by Arnold N. Sommerfeld (7,8), a late 1800's era mathematician, "used as a feed-line at UHF to link high frequency transmitters and receivers to their antennas, and in scientific research." (1) Depicted in Fig.10, "The Goubau line itself consists of a single wire conductor coated with dielectric material.(2) Coupling to and from the G-line is done with conical metal "launchers “or "catchers", with their narrow ends connected for example to the shield of coaxial feed line, and with the transmission line passing through a hole in the conical tips (2) which are used to carry lower frequency radio signals, have high losses at the upper end of the UHF band, and are almost useless for distances over 100 feet (33 meters).(2) Goubau lines can serve as low loss antenna feed-lines at these frequencies, up to microwave frequencies where a wave-guide must be used."(2)

A G-line is a type of waveguide, rather than a wire in an electric circuit. The G-line functions by slowing the propagation velocity of EM waves below the free-space velocity, causing the wave fronts to slightly bend inwards towards the conductor, which keeps the waves entrained. Bends of large radius are tolerated, but too sharp a bend in the single wire will cause the line to radiate and lose energy into space. In theory the dielectric coating is a requirement, it slows the wave and focuses it along the wire. But some users note that in practice the finite conductivity of metals may produce a similar effect, and a bare G-line can entrain a propagating wave. Other structures besides horns have been used to couple radio waves into and out of Goubau lines; waves can be "launched" from planar structures like tapered coplanar waveguides at much higher frequencies, into the terahertz band. The dimension of the single metallic conductor is then typically 1 µm (9). The Goubau line conducts energy via one-dimensional electromagnetic surface waves, analogous to the two-dimensional surface waves called ground waves that carry the signal from MF AM broadcasting stations to home AM radios. The ability of surface waves to bend and follow the contour of a conductor explains why AM radio stations can be received on the far side of hills, and how over-the-horizon radar works.

Nano tech, for this technology, is integral to the system in both internal and external use cases. the Thz frequencies are of the right intensity to breach the skin, allowing transmission to reach potential tech inside of a subject to provide them with power and data transmission is an application that is not quiet in the field; "We present an approach for implanting radio frequency transmission lines in biological tissue, using a single insulated wire surrounded by tissue as a variant of the Goubau single-wire transmission line (SWTL) in air. We extend the Goubau SWTL model to include SWTLs surrounded by lossy dielectrics such as tissue by assuming a propagating mode component in the tissue." (10). also, when thinking about the propagation of the wave itself, a theoretical transmission system involving a line of MEMs to receive and out put the waves in a non-uniform chain can be achieved if each item were to engage in line of sight transmission with the concurrent receiver, this was, the wave can be transmitted substantial distances with absolute minimum loss.

The two most prevalent names I have run across in the field of Goubau development are Bertrand Bocquet, and Anthony Treizebré. who are noted in the very next reference to be affiliates of " Institute of Electronics Microelectronics and Nanotechnology (IEMN), UMR CNRS 8520, University of Lille 1, Villeneuve d’Ascq, France", noted in a paper expressing another unique feature of these Thz waves, that of an interferometer, I will link the paper I’m referring to, however, interferometry has a simple definition, "Interferometry is a family of techniques in which waves, usually electromagnetic waves, are superimposed causing the phenomenon of interference in order to extract information" (11) the paper describing the intent is relayed in "TERAHERTZ INTERFEROMETER FOR INTEGRATED GOUBAU-LINE WAVEGUIDES" (12).

Looking at a paper from 2009 entitled "A Microwave Dielectric Biosensor Based on Suspended Distributed MEMS Transmission Lines" (13) it seems that the daisy chain type transmission system via mems was shown to be more than a theory, "In this paper, a biosensor that is based on a distributed MEMS transmission line has been presented. The biosensor was assembled with a DMTL chip and a microchannel device that allows bio samples to interact with the electromagnetic field through the DMTL." (13)

One of the drawbacks of Thz waves has been water in the past, this I’m sure was a large factor in the prevention of this tech development before the past 2 decades, however, as of recent this has been overcome, There is another notable member of the Thz wave community who had a presentation to physics students in some university about microfilms of water being able to generate Thz waves. i cannot find the video however there seem to have been more findings corroborating precisely what he was explaining stating, "The key to getting liquid water to generate THz waves, as the scientists show in the new study, is to use a very thin (less than 200 μm-thick) free-flowing film of water.(14,15) depicted here:

Aside from barriers and subsequent penetration via various techniques developed, the technology itself has been synonymous with Electromagnetic surface waves. meaning that without physical barriers, the curvature of the earth is not a hindrance in that is will skim the surface of the earth along its course, this also attributes to its high efficiency on a base level. Why I mention this is to lead into the area of research it was involved in greatly before the existence of MEMs as we know them today. The DOD has extensive data on its use of EM surface waves minimally as an efficient radar jamming technique, also during that time period, 1960 - 1980, microwave weaponry was integral in naval defense. This likely explains why this technology is so scarcely known or understood. I will be providing both documents regarding military use as sources (16, and 17). Lastly, I will note that tesla had spoken of a wave that can skim the earth as to overcome being dissipated within the curvature. The more tenable comparison to that time period is that of a Zenneck wave, "At high frequencies, a type of surface wave called Zenneck waves can propagate along a surface. They travel better on some materials than others, but performance is best with a conductor covered in a dielectric material. As with wires, these surfaces can carry high bandwidth, are secure, do not cause interference, and require little power. But as with wireless communication, physical contact is not required." (18)

in conclusion, this is an incredibly multifaceted technology of the likes i cannot compare to much anything else. To poke a little further, look up Solaren space energy transmission system. The same philosophies of this Goubau system seem to line up perfectly with the requirements of such a long range transmission to be at all feasible. Food for thought. Enjoy the sources, please inform/ debate if inconsistencies are noticed, or that I’m just plain incorrect in some of my assumptions.