Circularly Polarized Antenna Assembly With Switchable Radiation Modes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing antenna systems are often large, costly, and not feasible for panel mount applications, lacking the ability to be compact, efficient, and easily manufactured with standard components while providing adaptable radiation patterns for different communication applications.
Innovation Solution
A compact antenna assembly with a ground plane and equidistantly positioned antenna elements that can switch between right-hand circularly polarized omnidirectional, broadside, and left-hand circularly polarized broadside radiation patterns using a single feed port, with an optional reflector for tilting radiation to create a conical pattern.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If typical omnidirectional circularly polarized antennas (normal mode helical or cloverleaf) are used, then circular polarization and omnidirectional radiation are achieved, but the antenna has a high profile and is not feasible for panel mount applications
Solution Approach 1:
The antenna is divided into multiple planar elements (e.g., four L-shaped or U-shaped elements) arranged in a circular pattern on a single plane. Each element is fed with a specific phase shift (0°, 90°, 180°, 270°) to create circular polarization. This segmentation allows the antenna to achieve circular polarization and omnidirectional radiation while maintaining a low profile suitable for panel mounting.
Solution Approach 2:
The invention transitions from three-dimensional structures (helical antennas) to two-dimensional planar elements arranged in a circular configuration. By using multiple planar elements spaced around a circle and applying phase shifts, the antenna achieves circular polarization without requiring vertical height, thus converting a 3D problem into a 2D solution.
2Volume of moving object
If higher-order-mode patch antennas are used, then omnidirectional radiation is achieved, but the antenna is electrically large (larger than one electrical wavelength)
Solution Approach 1:
The antenna is divided into multiple smaller planar elements (L-shaped or U-shaped) arranged in a circular pattern. Each element is electrically small compared to a wavelength, but their collective arrangement and phase-shifted feeding create omnidirectional radiation. This segmentation allows omnidirectional capability without requiring a large single-element structure.
Solution Approach 2:
Multiple electrically small planar elements are combined in a circular configuration with specific phase relationships. The radiation patterns of individual elements are merged through coherent addition with phase shifts, creating an omnidirectional pattern. This combining of multiple small elements achieves omnidirectional radiation without the size penalty of a single large element.
3Adaptability or versatility
If multiple antennas are provided for different communication types, then different communication requirements are met, but the cost and occupied area increase
Solution Approach 1:
The antenna is designed with multi-functionality to serve multiple communication applications. By providing multiple feed ports that can be independently activated or combined, the single antenna structure can operate in different modes (omnidirectional, directional, different polarizations) to support various communication types including cellular, satellite, and wireless local area networks, replacing what would traditionally require multiple separate antennas.
Solution Approach 2:
The antenna incorporates dynamic switching capability through multiple feed ports and phase control. Different combinations of feed ports can be activated depending on the communication application requirements. The phase relationships between elements can be dynamically adjusted to change radiation patterns and polarization, allowing the antenna to adapt to different communication scenarios without physical reconfiguration.
Data Source
AI summary
An antenna assembly includes a ground plane having a periphery. The antenna assembly includes a plurality of antenna elements. Each antenna element is resonant at a frequency f. The antenna elements are positioned generally equidistant from each other around the periphery. The antenna elements are electrically connected to a single antenna feed port. The antenna elements provide a right-hand circularly polarized (RHCP) generally omnidirectional radiation pattern in a first operation mode. The antenna elements provide a right-hand circularly polarized (RHCP) broadside radiation pattern in a second operation mode. The antenna elements provide a left-hand circularly polarized (LHCP) broadside radiation pattern in a third operation mode. The antenna assembly includes a reflector positioned below the antenna elements. The reflector tilts a maximum radiation of the antenna elements upward by a tilt angle in the first operation mode to create a conical radiation pattern.