MODULATED GUIDED SURFACE WAVES
Disclosed are various systems and methods directed to the launching of a Zenneck surface wave embodying a modulated signal using a guided surface waveguide probe. A modulated signal is generated and coupled to a guided surface waveguide probe. A resulting Zenneck surface wave is launched that decays exponentially as a function of distance.
1 . A system, comprising:
modulation circuitry configured to generate a modulated signal; and
a guided surface waveguide probe configured to launch a Zenneck surface wave embodying the modulated signal along a lossy conducting medium.
2 . The system of claim 1 , wherein an electromagnetic field of the Zenneck surface wave decays exponentially as a function of distance from the guided surface waveguide probe.
3 . The system of claim 1 , wherein the modulated signal is generated using a carrier signal received from a carrier source and an information signal received from a information source.
4 . The system of claim 1 , further comprising a control system, the control system being configured to adjust an operation of the guided surface waveguide probe based at least in part on one or more environmental conditions.
5 . The system of claim 1 , wherein the modulation circuitry further comprises amplitude modulation circuitry, and a modulation type of the modulation performed by the amplitude modulation circuitry comprises a double-sideband full carrier, a single-sideband reduced-carrier, a single-sideband full-carrier, single-sideband suppressed-carrier, an independent-sideband emission, a vestigial-sideband, or a linked compressor and expander.
6 . The system of claim 1 , further comprising:
a feed network electrically coupled to a charge terminal of the guided surface waveguide probe, the feed network providing a phase delay (Φ) that matches a wave tilt angle (Ψ) associated with a complex Brewster angle of incidence (θ i,B ) of the lossy conducting medium in a vicinity of the guided surface waveguide probe.
7 . The system of claim 6 , wherein the modulation circuitry is coupled to a phase delay circuit of the feed network.
8 . A method, comprising:
generating a modulated signal; and
adjusting a guided surface waveguide probe to launch a Zenneck surface wave embodying the modulated signal along a lossy conducting medium via a guided surface waveguide probe.
9 . The method of claim 8 , further comprising coupling the modulated signal to the guided surface waveguide probe.
10 . The method of claim 8 , wherein the guided surface waveguide probe comprises a charge terminal elevated over the lossy conducting medium configured to generate at least one resultant field that synthesizes a wave front incident at a complex Brewster angle of incidence (θ i,B ) of the lossy conducting medium at a vicinity of the guided surface waveguide probe.
11 . The method of claim 8 , wherein the guided surface waveguide probe further comprises a feed network electrically coupled to a charge terminal, the feed network providing a phase delay (Φ) that matches a wave tilt angle (Ψ) associated with a complex Brewster angle of incidence (θ i,B ) associated with the lossy conducting medium in a vicinity of the guided surface waveguide probe.
12 . The method of claim 8 , wherein an electromagnetic field of the Zenneck surface wave decays exponentially as a function of a distance from the guided surface waveguide probe.
13 . The method of claim 8 , further comprising
receiving an information signal from an information source;
receiving a carrier signal from a carrier source; and
wherein generating the modulated signal comprises modulating the carrier signal based at least in part on the information signal.
14 . An apparatus, comprising:
modulation circuitry configured to generate a modulated signal; and
a guided surface waveguide probe coupled to the modulation circuitry, the guided surface waveguide probe being adjusted to launch a Zenneck surface wave along a lossy conducting medium, the Zenneck surface wave embodying the modulated signal.
15 . The apparatus of claim 14 , further comprising a matching network, the modulation circuitry being coupled to the guided surface waveguide probe via the matching network.
16 . The apparatus of claim 15 , wherein the matching network is employed to minimize creation of a skywave.
17 . The apparatus of claim 14 , wherein an electromagnetic field of the guide surface wave decays exponentially as a function of distance from the guided surface waveguide probe.
18 . The apparatus of claim 14 , wherein the modulation circuitry comprises a modulation subsystem, a carrier source, an information signal source and an amplifier, the modulation subsystem being configured to modulate a carrier signal received from the carrier source using an information signal received from the information signal source.
19 . The apparatus of claim 14 , wherein the guided surface waveguide probe comprises a charge terminal and a feed network electrically coupled to the charge terminal, and further comprising generating a resultant field that matches a wave tilt angle (Ψ) associated with a complex Brewster angle of incidence (θ i,B ) associated with the lossy conducting medium associated with the guided surface waveguide probe.
20 . The apparatus of claim 19 , wherein the modulated signal is an amplitude modulated signal.