Airborne Weather Radar Aperture Segmentation for Terrain Elevation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional terrain awareness systems face challenges in accurately estimating terrain elevation, particularly during precipitation, due to beam shape effects and contamination from weather returns, and there is a need for a low-cost, radar-based terrain sensor that is less susceptible to noise and beam shape issues.
Innovation Solution
The method involves using an airborne weather radar to sample returns from specific portions of the antenna, combining them to form a null response, which helps in determining terrain elevation by distinguishing terrain from weather conditions, thereby reducing noise and beam shape effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional radar-based terrain awareness systems are used, then terrain elevation can be sensed, but the measurement precision deteriorates due to beam shape effects and contamination from weather returns
Solution Approach 1:
The patent divides the antenna aperture into multiple segments (first portion and second portion) and processes returns from each segment separately. By segmenting the antenna aperture and comparing returns from different portions, the system can identify and eliminate weather contamination while preserving terrain information, thereby improving measurement precision despite harmful weather returns
Solution Approach 2:
The patent extracts and removes the harmful weather return component from the total radar return by comparing returns from different antenna portions. The system identifies the weather contamination separately and subtracts it from the composite signal, leaving only the terrain return for accurate elevation measurement
2Reliability
If conventional radar systems operate during precipitation, then terrain sensing continues, but reliability deteriorates due to heavy weather return contamination
Solution Approach 1:
The patent converts the harmful weather returns into a useful reference signal. By using the weather returns detected by one antenna portion as a reference, the system can identify and remove this contamination from the total signal, thereby maintaining reliable terrain sensing even during heavy precipitation
3Measurement precision
If additional hardware is added to improve terrain sensing accuracy, then measurement precision improves, but device complexity increases
Solution Approach 1:
The patent makes the existing radar antenna serve multiple functions by processing returns from different portions of the same antenna for both weather detection and terrain sensing. This multi-functional approach improves measurement precision without adding separate hardware components, thereby avoiding increased device complexity
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 provides a more accurate and reliable terrain elevation estimation, even in adverse weather conditions, with a sharper response that enhances the ability to differentiate between terrain and weather returns, improving safety in aviation by providing clearer flight data.
Implementation Method 1
The method samples returns from a first portion and a second portion of the antenna
Data Source
AI summary
A system and method for sensing elevation terrain using an airborne weather radar. Method techniques include sampling first and second radar returns from a weather radar at two portions of an antenna. First radar returns are removed from second radar returns to generate third radar returns for a third portion of the antenna. The third portion of the antenna is included in the second portion but not the first portion. Changes in the third radar return are analyzed to sense elevation of the terrain.