Traveling-Wave Array Antenna Feed Line Geometry for Tilt Angle Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Vehicle-mounted radar systems face limitations in adjusting the elevation tilt angle of their radar beams due to the narrow frequency band, allowing only approximately 2° adjustment, which is insufficient for effective obstacle detection.
Innovation Solution
The design of a traveling-wave fed array antenna with a feed line configuration where the inter-element line length is longer than the arranging interval, allowing for increased phase variation and beam direction adjustment across a wider range without increasing circuit scale or signal processing complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the frequency of the fed signal is varied to adjust the tilt angle, then the beam direction can be changed, but the tilt angle adjustment range is limited to approximately 2° due to the narrow frequency band (76 GHz to 77 GHz)
Solution Approach 1:
The patent transitions from adjusting beam direction solely through frequency variation (one-dimensional approach) to a two-dimensional approach by introducing inter-element line length as an additional control parameter. By making the feed line length between radiating elements longer than the element spacing, the system achieves tilt angle adjustment up to 6°, tripling the adjustment range available through frequency control alone.
2Adaptability or versatility
If electronic signal processing such as DBF or MUSIC is used to adjust the tilt angle, then the tilt angle can be adjusted, but the circuit scale and signal processing amount increase
Solution Approach 1:
The patent replaces complex electronic signal processing systems (DBF, MUSIC) with a simplified feed line structure where the inter-element line length is deliberately made longer than the radiating element spacing. This structural modification enables tilt angle control through basic feed line geometry rather than requiring sophisticated digital signal processing circuits, thereby reducing circuit scale and processing complexity while maintaining tilt angle adjustment capability.
3Adaptability or versatility
If a specific hardware device such as a dielectric lens, Rotman lens or Butler matrix is used for beam scanning, then the beam transmission angle can be set to a desired elevation tilt angle, but the circuit scale and signal processing amount increase
Solution Approach 1:
The patent extracts the essential function of tilt angle control from complex beam scanning hardware devices (dielectric lens, Rotman lens, Butler matrix) and implements it through a simplified feed line configuration. By making the inter-element line length longer than the element spacing, the system achieves the desired elevation tilt angle control without requiring these bulky and complex hardware components, thereby reducing device complexity while preserving beam direction control capability.
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 configuration enables a wider range of beam direction adjustment, achieving up to 6° variation in tilt angle within the narrow frequency band, enhancing the radar system's ability to detect obstacles without increasing circuit size or processing complexity.
Implementation Method 1
a plurality of radiating element sections arranged at a predetermined arranging interval in a first direction, each of the radiating element sections including at least one radiating element fed a traveling wave through the feed line
Data Source
AI summary
The array antenna includes a feed line, and a plurality of radiating element sections arranged at a predetermined arranging interval in a first direction, each of the radiating element sections including at least one radiating element fed a traveling wave through the feed line. The inter-element line length as a length of the feed line between each succeeding two of the radiating element sections is longer than the arranging interval in the first direction.