High Isolation Multi-Band Monopole Antenna Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In MIMO systems, placing antennas in close proximity leads to mutual surface radiation coupling, defocusing of main beam radiation due to ground reflectors, and low isolation, causing signal interference and band-to-band coupling, which are challenging to address under space constraints.
Innovation Solution
A high isolation multi-band monopole antenna design incorporating an RF choke to reduce reflection interference and a high pass circuit to prevent band-to-band coupling, allowing for close antenna placement without compromising beam width or increasing interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If antennas are placed in close proximity to reduce space usage, then space efficiency is improved, but mutual surface radiation coupling and signal interference increase
Solution Approach 1:
The patent introduces an RF choke as an intermediary component between the antenna and ground reflector. This RF choke acts as a mediator that blocks surface radiation currents while allowing the antenna to maintain its radiation pattern. By placing this intermediary element, the harmful mutual coupling between closely spaced antennas is prevented without requiring increased separation distance.
Solution Approach 2:
The patent extracts and removes the harmful surface radiation component from the system by using the RF choke to block surface currents on the ground reflector. This extraction of the harmful surface wave component allows the antennas to operate in close proximity without experiencing mutual coupling effects.
2Area of stationary object
If antennas are placed in close proximity to reduce space usage, then space efficiency is improved, but isolation between antennas deteriorates
Solution Approach 1:
The RF choke serves as an intermediary that provides high impedance to surface currents, thereby improving isolation between antennas. This mediator component allows the system to achieve 40 dB isolation even when antennas are placed within 0.5 wavelength of each other, which would normally provide insufficient isolation.
3Power
If antennas are elevated above a large ground reflector to improve radiation, then radiation performance is improved, but a small antenna base defocuses the reflection of the main beam
Solution Approach 1:
The patent extracts the harmful surface radiation component that causes defocusing effects. By removing this surface wave component through the RF choke, the main beam reflection from the ground reflector remains focused and effective, even with a small antenna base.
4Productivity
If wide beam antennas are used to exploit multi-path capabilities, then system capacity is improved, but interference and band-to-band coupling between beams increase
Solution Approach 1:
The RF choke acts as a mediator that prevents surface radiation from coupling between antennas operating at different frequency bands. This allows wide beam antennas to be used for multi-path exploitation while maintaining isolation between different frequency bands through the high impedance barrier provided by the RF choke.
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 achieves up to 40 dB isolation between antennas, reducing interference and maintaining wide beam characteristics, even when antennas are in close proximity, thereby enhancing MIMO system performance.
Implementation Method 1
mutual surface radiation from the antennas can couple with each other
Implementation Method 2
band-to-band coupling between beams from antennas operating at different frequencies
Implementation Method 3
when the antennas are elevated above a large ground reflector, a small antenna base can defocus the reflection of the main beam radiation
Data Source
AI summary
A high isolation multi-band monopole antenna that can be used in connection with MIMO systems is provided. The antenna can include various components to prevent band to band coupling and provide isolation from neighboring antennas.