Asymmetric MIMO Antenna Structure for Close-Spaced Element Isolation
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Solution Overview
Problem
The challenge of reducing mutual coupling and improving isolation between closely spaced MIMO antenna elements in wireless communication devices due to limited space, which affects the performance of MIMO systems.
Innovation Solution
An asymmetric MIMO antenna structure with a connection structure that includes extendable series and parallel stubs and capacitors to adjust impedance, allowing for decoupling and improved isolation between antenna elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If MIMO antenna elements are deployed close together to achieve miniaturization, then device size is reduced, but mutual coupling between antennas increases and isolation decreases
Solution Approach 1:
A connection structure comprising series stubs and parallel stubs is introduced as an intermediary between the first and second antenna elements. This intermediate structure acts as a decoupling mechanism that reduces mutual coupling while allowing the antenna elements to remain in close proximity, thus maintaining miniaturization while improving isolation.
Solution Approach 2:
The connection structure utilizes adjustable electrical parameters including the length of series stubs, the length of parallel stubs, and capacitance values of capacitors. By optimizing these parameters, the decoupling performance is maximized, achieving high isolation between antenna elements despite their close spacing.
2Adaptability or versatility
If antenna elements are placed close together, then spatial efficiency is improved, but coupling between elements increases
Solution Approach 1:
The connection structure serves as a mediator that enables close spacing of antenna elements for spatial efficiency while simultaneously suppressing the harmful coupling effect. The series and parallel stubs create impedance transformations that decouple the electromagnetic fields of adjacent elements.
Solution Approach 2:
The connection structure employs asymmetric configuration of series and parallel stubs with different lengths and positions. This asymmetry allows selective cancellation of coupling paths while maintaining the desired radiation patterns and impedance matching of each antenna element.
3Reliability
If connection structure is added to decouple antenna elements, then isolation is improved, but device complexity increases
Solution Approach 1:
The connection structure merges multiple functions into a single integrated component: impedance transformation, decoupling, and current balancing are all achieved through the combined series and parallel stub configuration, reducing the need for separate components and simplifying the overall antenna design.
Solution Approach 2:
By providing adjustable parameters (stub lengths, capacitor values) within the connection structure, the design allows for optimization of decoupling performance without adding structural complexity. These parameters can be tuned to achieve the desired isolation level while maintaining a compact and simple overall architecture.
Data Source
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AI summary
This application relates to the field of communication technologies, and in particular, to an antenna and a communication device. The antenna includes a first antenna element, a second antenna element, and a connection structure. The first antenna element and the second antenna element each have a feed point. The connection structure connects the first antenna element to the second antenna element. The connection structure is extendable in a direction perpendicular to a connection direction of the first antenna element and the second antenna element. The connection structure adjusts isolation between the first antenna element and the second antenna element through extension. In this application, isolation between two adjacent antenna elements can be improved through a connection structure.