REMOTE SURFACE SENSING USING GUIDED SURFACE WAVE MODES ON LOSSY MEDIA
Disclosed are various systems and methods for remote surface sensing using guided surface wave modes on lossy media. One system, among others, includes a guided surface waveguide probe configured to launch a guided surface wave along a surface of a lossy conducting medium, and a receiver configured to receive backscatter reflected by a remotely located object illuminated by the guided surface wave. One method, among others, includes launching a guided surface wave along a surface of a lossy conducting medium by exciting a charge terminal of a guided surface waveguide probe, and receiving backscatter reflected by a remotely located object illuminated by the guided surface wave.
1 . A system, comprising:
a guided surface waveguide probe configured to launch a guided surface wave along a surface of a lossy conducting medium by individually exciting each of a plurality of charge terminals, the plurality of charge terminals elevated over the lossy conducting medium, where the excitation of the plurality of charge terminals synthesizes a wave front incident with the lossy conducting medium at a complex Brewster angle of incidence (θ i,B ) of the lossy conducting medium; and
a receiver configured to receive backscatter reflected by a remotely located object illuminated by the guided surface wave.
2 . The system of claim 1 , wherein synthesizing the wave front incident with the lossy conducting medium at the complex Brewster angle of incidence (ƒ i,B ) of the lossy conducting medium results in substantially zero reflection.
3 . The system of claim 1 , wherein the guided surface waveguide probe is configured to launch a series of guided surface waves having a defined pulse duration at a defined repetition rate.
4 . The system of claim 1 , wherein the guided surface wave is a frequency modulated continuous wave.
5 . The system of claim 1 , wherein the remotely located object is on or above the surface of the lossy conducting medium.
6 . The system of claim 5 , wherein the remotely located object is a low flying aircraft.
7 . The system of claim 1 , comprising a plurality of guided surface waveguide probes comprising the guided surface waveguide probe, the plurality of guided surface waveguide probes configured to launch guided surface waves along the surface of the lossy conducting medium.
8 . The system of claim 1 , comprising a plurality of receivers comprising the receiver, the plurality of receivers configured to receive backscatter reflected by the remotely located object illuminated by the guided surface wave.
9 . The system of claim 1 , wherein the lossy conducting medium is a terrestrial medium.
10 . A method, comprising:
launching guided surface waves along a surface of a lossy conducting medium by individually exciting charge terminals of an array of guided surface waveguide probes, the charge terminals elevated over the lossy conducting medium; and
receiving, in a receiver, backscatter reflected by a remotely located object illuminated by the guided surface waves.
11 . The method of claim 10 , wherein the array of guided surface waveguide probes is configured to focus the guided surface waves in at least one direction.
12 . The method of claim 10 , wherein the array of guided surface waveguide probes is configured to increase a field strength of the guided surface waves in at least one direction.
13 . The method of claim 10 , wherein the array of guided surface waveguide probes is configured to produce at least one transmission node in at least one direction.
14 . The method of claim 10 , wherein the array of guided surface waveguide probes is configured to launch a series of guided surface waves having a defined pulse duration at a defined repetition rate.
15 . The method of claim 10 , comprising determining a characteristic of the remotely located object based at least in part upon the backscatter.
16 . A method, comprising:
launching a guided surface wave along a surface of a lossy conducting medium by individually exciting one or more charge terminals of a guided surface waveguide probe, the one or more charge terminals elevated over the lossy conducting medium, where the excitation of the one or more charge terminals synthesizes a wave front incident with the lossy conducting medium at a complex Brewster angle of incidence (θ i,B ) of the lossy conducting medium; and
receiving, in an array of receivers, backscatter reflected by a remotely located object illuminated by the guided surface wave.
17 . The method of claim 16 , wherein the one or more charge terminals comprises a plurality of charge terminals.
18 . The method of claim 16 , comprising determining a characteristic of the remotely located object based at least in part upon the backscatter.
19 . The method of claim 16 , comprising determining a location and a direction of the remotely located object based at least in part upon the backscatter.
20 . The method of claim 16 , wherein the remotely located object is on or above the surface of the lossy conducting medium.