Underground Positioning Using Low-Frequency Electromagnetic Signals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for determining the position of underground sensors in oil and gas exploration are inefficient due to signal attenuation and sensitivity to geological formation properties, particularly at higher frequencies, which complicates accurate positioning.
Innovation Solution
The use of low-frequency electromagnetic waves and a system with multiple triad transmitters and receivers, along with inversion schemes and semi-analytical formulations, to determine the position of underground receivers by processing signals from known transmitter locations, allowing for precise depth and orientation determination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If high-frequency electromagnetic waves are used for positioning, then measurement precision improves, but signal attenuation increases and reliability deteriorates
Solution Approach 1:
The patent changes the frequency parameter of electromagnetic waves from high-frequency to low-frequency range. This parameter change reduces signal attenuation in the underground formation, allowing signals to reach deeper depths (up to 10,000 meters) while maintaining sufficient signal strength for accurate positioning measurements.
Solution Approach 2:
The system dynamically adjusts operational parameters including frequency selection based on formation properties and depth requirements. The inversion process dynamically optimizes positioning calculations by iteratively refining estimates based on received signal characteristics, allowing the system to adapt to varying geological conditions.
2Measurement precision
If multiple transmitters and receivers are deployed to improve positioning accuracy, then measurement precision improves, but device complexity increases
Solution Approach 1:
The positioning system is segmented into distinct functional components: multiple transmitters deployed at known locations, receivers positioned in the underground formation, and separate signal processing/inversion systems. This segmentation allows each component to be optimized independently while maintaining overall system accuracy.
Solution Approach 2:
The patent introduces an inversion process as an intermediary computational step between signal reception and position determination. This intermediary process processes the raw signal data from multiple transmitters and receivers, applying mathematical transformations to extract accurate position information while filtering out noise and accounting for formation properties.
3Length of stationary object
If low-frequency electromagnetic waves are used, then signal penetration depth improves, but measurement precision deteriorates
Solution Approach 1:
The patent merges data from multiple low-frequency transmitter signals received at the underground receiver location. By combining information from multiple transmitters positioned at different known locations, the system achieves both deep penetration (inherent to low-frequency waves) and improved positioning accuracy through the synergistic effect of multiple signal sources.
Solution Approach 2:
The patent replaces direct high-precision measurement methods with an inversion-based computational approach. Instead of relying on single high-frequency signals that attenuate rapidly, the system uses low-frequency signals combined with mathematical inversion techniques to achieve accurate positioning at great depths, substituting computational complexity for physical measurement limitations.
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
This approach enables accurate positioning of underground receivers at depths up to 10,000 meters with improved resolution and reduced noise, even in complex geological formations, by utilizing low-frequency signals and advanced signal processing techniques.
Implementation Method 1
receiving electromagnetic signals from a receiver in an underground formation in response to electromagnetic signals generated from three or more transmitting sources
Data Source
AI summary
Various embodiments include apparatus and methods related to finding a position in an underground formation. Apparatus and methods can include receiving signals from a receiver in an underground formation in response to signals generated from transmitting sources, each of the transmitting sources located at a known position; and processing the received signals, based on the signals generated from the transmitting sources, to determine the position of the receiver. A number of techniques can be applied to processing the received signal. Additional apparatus, systems, and methods are disclosed.