Guided Surface Waveguide Probe for Lossy Media Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
For over a century, there has been no practical structure for efficiently launching open surface guided waves over planar or spherical surfaces of lossy, homogeneous media, despite theoretical possibilities.
Innovation Solution
Guided surface waveguide probes are configured to excite electric fields that couple into a guided surface waveguide mode along the surface of a lossy conducting medium, such as the Earth, by synthesizing a wave front incident at a complex Brewster angle, resulting in zero reflection and launching a guided electromagnetic field as a guided surface wave.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If conventional antenna structures are used to transmit radio waves, then radiation fields can be launched, but efficient coupling into guided surface wave modes cannot be achieved
Solution Approach 1:
The probe structure changes the electrical parameters (impedance, phase, amplitude) of the excited field to match the complex Brewster angle requirements of the lossy conducting medium, enabling efficient coupling into guided surface wave modes while minimizing energy loss in bound charge
2Productivity
If a guided surface waveguide probe is used to excite electric fields at a complex Brewster angle, then zero reflection and efficient guided surface wave launching are achieved, but the device complexity increases
Solution Approach 1:
The guided surface waveguide probe acts as an intermediary structure between the excitation source and the lossy conducting medium, transforming the excitation fields into the specific complex Brewster angle wavefront required for efficient guided surface wave mode coupling
Solution Approach 2:
The probe structure is designed with specific geometric parameters and electrical characteristics that enable it to generate fields with the required complex amplitude and phase distribution corresponding to the complex Brewster angle, achieving efficient energy transfer
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution enables the efficient launch of guided surface waves along lossy conducting media, achieving exponential decay perpendicular to the surface and resembling propagation in a radial transmission line, with improved energy coupling and reduced bound charge on the charge terminal.
Implementation Method 1
by synthesizing a wave front incident at a complex Brewster angle, resulting in zero reflection and launching a guided electromagnetic field as a guided surface wave
Implementation Method 2
launching a guided electromagnetic field as a guided surface wave... achieving exponential decay perpendicular to the surface and resembling propagation in a radial transmission line
Data Source
AI summary
Disclosed are various systems and methods for remote surface sensing using guided surface wave modes on lossy media. One system, among others, comprises 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 subsurface 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 subsurface object illuminated by the guided surface wave.