Antenna Radome with Embedded RF Absorbers for Side-Lobe Reduction
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Solution Overview
Problem
Conventional radomes for microwave dish antennas often fail to effectively attenuate side-lobe and back-lobe radiation, leading to interference and performance degradation, especially when used without a shield.
Innovation Solution
A radome design incorporating a bulk lightweight material with RF-absorbent absorbers, such as carbon-loaded foam, embedded or attached near the perimeter, to attenuate side-lobe and back-lobe radiation while maintaining minimal impact on antenna gain.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a conventional radome is used without a shield, then the device complexity is reduced, but the side-lobe and back-lobe radiation attenuation is insufficient
Solution Approach 1:
The radome incorporates RF-absorbent absorbers at specific locations (near the perimeter and/or at the back surface) rather than making the entire radome absorptive. This localized application of absorbing material provides side-lobe and back-lobe attenuation while maintaining the overall simplicity of the radome structure without requiring a separate shield.
Solution Approach 2:
The radome is constructed as a composite structure combining a bulk radome material with RF-absorbent absorbers integrated into it. This composite approach enables the radome to simultaneously provide environmental protection, maintain structural simplicity, and attenuate unwanted radiation patterns through the embedded absorptive materials.
2Object-generated harmful factors
If absorbers are added to the radome, then the side-lobe and back-lobe radiation is attenuated, but the manufacturing complexity increases
Solution Approach 1:
The absorbers are nested within or integrated into the radome structure itself, with absorbers positioned at the back surface or near the perimeter being incorporated during radome fabrication. This nesting approach allows the absorbers to be manufactured as part of the radome assembly process rather than as separate components requiring additional installation steps.
3Object-generated harmful factors
If absorbers are embedded in the radome, then the side-lobe and back-lobe radiation is reduced, but the radome material homogeneity is compromised
Solution Approach 1:
The radome maintains homogeneous bulk material composition while incorporating absorbers only at specific locations where they are needed for radiation control. The absorbers are strategically positioned near the perimeter and/or at the back surface, leaving the majority of the radome structure as uniform material, thus preserving overall compositional stability while providing localized radiation attenuation.
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 radome effectively reduces side-lobe and back-lobe radiation by up to 5-7% of the antenna aperture area, enhancing antenna performance and regulatory compliance without significantly affecting transmission efficacy.
Implementation Method 1
The set of one or more absorbers is adapted to attenuate side-lobe and back-lobe radiation from the antenna
Data Source
Figure 1
Figure 2
Figure 3A~3B
AI summary
In one embodiment, an antenna assembly includes a reflector antenna whose aperture is covered by a radome. The radome has a principle plane corresponding to the azimuth axis of the antenna. The radome has a bulk material and a pair of absorbers made of a radio-frequency(RF)-absorbent material different from the bulk material. The pair of absorbers are arranged symmetrically along the principle plane and about the center of the radome. The pair of absorbers are located near the perimeter of the radome and are at least partially embedded in the bulk material. The pair of absorbers cover from 4%-8% of the total aperture area of the antenna.