Dielectric Lens Beam Shaping for Uniform Rear Bench Radar Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing radar devices for automotive interior sensing applications face challenges in maintaining consistent radar power distribution across different positions on a vehicle rear bench, leading to undesirable power variations that affect sensor performance.
Innovation Solution
A dielectric lens device comprising two plano-convex cylindrical dielectric lens members and a plane-parallel dielectric substrate, designed to shape the radar beam and produce a 'heart-shaped' radiation pattern with a local minimum between two maxima, balancing radar power transmission to the middle and outer positions on the rear bench.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional radar antenna with Gaussian-like radiation pattern is used, then the radar power transmitted to the middle position is stronger than to outer positions, but this leads to position-dependent sensor performance and undesirable power variations
Solution Approach 1:
A dielectric lens device is introduced as an intermediary component between the radar antenna and the vehicle interior space. This lens modifies the electromagnetic wave propagation by creating a heart-shaped radiation pattern with controlled lobes, thereby mediating the power distribution to achieve uniform detection across different seating positions without redesigning the antenna itself
Solution Approach 2:
The radiation pattern parameters are changed from a conventional Gaussian-like single-lobe pattern to a heart-shaped multi-lobe pattern. By adjusting the lens geometry and dielectric properties, the system transforms the power distribution characteristics to create two side lobes that compensate for the distance-dependent power attenuation, achieving position-independent detection
2Measurement precision
If the radar device is positioned to optimize detection at outer positions, then outer position detection improves, but middle position detection deteriorates due to increased distance
Solution Approach 1:
The radiation pattern is engineered to have different local characteristics in different angular regions. The heart-shaped pattern creates enhanced side lobes directed toward outer seating positions, providing localized power enhancement in those specific directions while maintaining adequate coverage at the middle position, thus compensating for distance variations
3Reliability
If a custom-designed radar antenna with balanced power distribution is created, then position-independent detection is achieved, but device complexity and manufacturing cost increase
Solution Approach 1:
The system is segmented into two independent functional components: a conventional radar antenna responsible for signal generation and reception, and a separate dielectric lens device responsible for beam shaping. This segmentation allows the use of standard, off-the-shelf antenna designs while achieving the complex heart-shaped radiation pattern through the lens, thereby reducing overall system complexity and manufacturing cost
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 dielectric lens device achieves position-independent radar sensor functionality by mitigating power maxima and minima, ensuring consistent radar power distribution and improving sensor performance across various vehicle configurations.
Implementation Method 1
a first plano-convex cylindrical dielectric lens member (16) and a second plano-convex cylindrical dielectric lens member (20)... configured to shape a radar beam
Data Source
AI summary
A dielectric lens device for shaping a radar beam includes a first and a second plano-convex cylindrical dielectric lens member and a plane-parallel dielectric substrate. The two plano-convex cylindrical dielectric lens members are arranged with their plane surfaces towards a same surface of the plane-parallel dielectric substrate. The plano-convex cylindrical dielectric lens members are interconnected to the plane-parallel dielectric substrate in a material fit.