Base Station Antenna Tuning Layout for Wide-Angle Cross-Polarization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Integrated base station antennas face challenges in maintaining good cross-polarization performance over a wide scanning angle range due to the positioning of passive and active antennas, with the passive antenna negatively impacting the active antenna's performance, especially at large scanning angles, and limited space for tuning elements.
Innovation Solution
The integration of an array of metal tuning elements positioned in front of the active antenna's radiating elements, with longitudinal axes at an angle between 70° and 110°, and mounted on printed circuit boards, enhances cross-polarization performance by providing different projection components for small and large scanning angles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the passive antenna is positioned in front of the active antenna, then the passive antenna can provide stable coverage, but the passive antenna negatively impacts the cross-polarization performance of the active antenna, especially at large scanning angles
Solution Approach 1:
A matching dielectric layer is introduced as an intermediary component between the passive antenna and the active antenna. This dielectric layer with specific permittivity and thickness acts as a mediator to reduce the negative impact of the passive antenna on the active antenna's cross-polarization performance, allowing both antennas to coexist effectively in the integrated structure.
Solution Approach 2:
The harmful effect of the passive antenna on the active antenna is extracted and addressed separately by introducing the matching dielectric layer. This layer specifically targets and mitigates the cross-polarization degradation issue without requiring changes to the passive antenna structure itself, isolating the problem solution from the overall antenna design.
2Reliability
If different tuning elements are installed for small and large horizontal scanning angles, then good cross-polarization performance can be maintained over a wide scanning angle range, but the available space in the active antenna is limited
Solution Approach 1:
Multiple tuning elements with different functions (for small scanning angles and large scanning angles) are merged into a single integrated array structure. The tuning elements are arranged in columns and rows within the same spatial footprint, combining multiple functions into one compact component that maintains good cross-polarization performance across the entire scanning angle range without requiring separate installations.
Solution Approach 2:
The tuning elements are arranged in a two-dimensional grid pattern (columns and rows) within the limited three-dimensional space of the active antenna. By utilizing the planar dimension efficiently, multiple tuning elements are packed into the available space without requiring additional volume, solving the space constraint problem while maintaining performance across different scanning angles.
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 improves peak cross-polarization discrimination rates by at least 2 dB across various scanning angles, maintaining optimal performance over a wide range.
Implementation Method 1
The array of metal tuning elements used for the array of radiating elements is mounted in the passive antenna, the array of metal tuning elements positioned right in front of the array of radiating elements of the active antenna
Data Source
AI summary
An integrated base station antenna comprises a passive antenna and an active antenna installed behind the passive antenna. The active antenna comprises a reflecting plate and an array of radiating elements extending forward from the reflecting plate. The passive antenna includes an array of metal tuning elements that tune the array of radiating elements, where the array of metal tuning elements us positioned in front of the array of radiating elements of the active antenna, and where a longitudinal axis of at least some of the metal tuning elements extend at an angle between 70° and 110° with respect to a plane defined by the reflecting plate.