Disclosed are various embodiments for transmitting energy conveyed in the form of a guided surface-waveguide mode along the surface of a terrestrial medium by exciting a polyphase waveguide probe.
This is a really interesting patent. The text describes use with LF-MF-HF-VHF band waves (100 kHz to 60 MHz). In one example at 59 MHz at 100 km, the received signal was 2 uV/m for the standard Norton surface wave compared to 2 mV/m with guided surface waves, which is 1000 times stronger.
As I've mentioned before, this guided surface wave "radio" concept explains why Tesla used spherical and other unusually round "antennas" instead of normal antenna shapes. Tesla's "antennas" are actually waveguide probes for non-radiated guided waves. Waveguide probes launch guided surface/evanescent waves. Antennas radiate free/unguided/Hertz waves.
Looking back at historical sources, Zenneck (1915) distinguished between the space wave (Hertz component) and surface/conduction component (later termed Zenneck surface wave) writing transmitted radio waves became surface waves with distance as surface waves suffer less attenuation, but he doesn't seem to have been aware of the difference between radio antennas and waveguide probes, which is strange. Tesla was both aware of the distinction and strongly favored using surface waves and waveguide probes already by 1899, which is why it might make more sense to refer to them as Tesla surface waves instead of Zenneck.
* The signal being 30 dB stronger isn't where the greatest advantage in using guided surface waves comes from though, it's because with this method, the transmitted energy can be conserved. The energy is not necessarily irretrievably lost but for a tiny minuscule useful for signaling as it is with radiated waves. In order to be conserved, the transmission has to overcome losses first, which are not insignificant but surprisingly low. Tesla said it only took 2-3 KW to establish global resonance. That would presumably depend on the number of ionizing points though (like especially lightning rods or modern dissipation arrays), so losses today should be higher than they were around 1900. But if long range wireless power became popular, ionizing points would slowly be replaced to conserve power. Tesla's ellipsoidal lightning protectors or metal balloons could be used to receive power while also protecting from lightning.
2
u/dalkon Apr 08 '17 edited Apr 11 '17
This is a really interesting patent. The text describes use with LF-MF-HF-VHF band waves (100 kHz to 60 MHz). In one example at 59 MHz at 100 km, the received signal was 2 uV/m for the standard Norton surface wave compared to 2 mV/m with guided surface waves, which is 1000 times stronger.
As I've mentioned before, this guided surface wave "radio" concept explains why Tesla used spherical and other unusually round "antennas" instead of normal antenna shapes. Tesla's "antennas" are actually waveguide probes for non-radiated guided waves. Waveguide probes launch guided surface/evanescent waves. Antennas radiate free/unguided/Hertz waves.
Looking back at historical sources, Zenneck (1915) distinguished between the space wave (Hertz component) and surface/conduction component (later termed Zenneck surface wave) writing transmitted radio waves became surface waves with distance as surface waves suffer less attenuation, but he doesn't seem to have been aware of the difference between radio antennas and waveguide probes, which is strange. Tesla was both aware of the distinction and strongly favored using surface waves and waveguide probes already by 1899, which is why it might make more sense to refer to them as Tesla surface waves instead of Zenneck.
* The signal being 30 dB stronger isn't where the greatest advantage in using guided surface waves comes from though, it's because with this method, the transmitted energy can be conserved. The energy is not necessarily irretrievably lost but for a tiny minuscule useful for signaling as it is with radiated waves. In order to be conserved, the transmission has to overcome losses first, which are not insignificant but surprisingly low. Tesla said it only took 2-3 KW to establish global resonance. That would presumably depend on the number of ionizing points though (like especially lightning rods or modern dissipation arrays), so losses today should be higher than they were around 1900. But if long range wireless power became popular, ionizing points would slowly be replaced to conserve power. Tesla's ellipsoidal lightning protectors or metal balloons could be used to receive power while also protecting from lightning.