Microstrip Balun Layout for Smooth Impedance Transition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current balance-unbalance conversion apparatuses are not conducive to cabling and occupy large spaces, making them inefficient for high-speed communications systems.
Innovation Solution
A balance-unbalance conversion apparatus is designed with gradient cross-sectional areas in microstrips and impedance matching sections on an insulation substrate, allowing for smooth impedance transition from differential to single-ended signals, reducing space requirements and manufacturing costs by integrating the apparatus on a substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a traditional balun with two transmission lines of equal lengths is used for balance-unbalance conversion, then impedance transition can be achieved, but the device occupies large space and is not conducive to cabling
Solution Approach 1:
The transmission line is divided into two segments with different characteristic impedances: a first transmission line section with impedance Z1 and a second transmission line section with impedance Z2. This segmentation allows the device to achieve impedance transformation functionality while reducing the overall space occupation compared to traditional equal-length transmission line configurations.
Solution Approach 2:
The patent changes the parameter of transmission line impedance by using two different characteristic impedances (Z1 and Z2) for the two sections. This parameter change enables the device to achieve both impedance matching and space reduction, as the different impedance values allow for optimized signal transmission through the balun structure with smaller physical dimensions.
2Object-affected harmful factors
If a biaxial transmission line is used for high-speed signal transmission, then differential signal immunity is improved, but the cable diameter is large and bending capability is limited
Solution Approach 1:
The transmission line structure is segmented into multiple sections with different characteristics. By dividing the transmission path into segments with different impedances and configurations, the system maintains noise immunity through differential signaling while reducing the overall cable diameter and improving flexibility for bending operations.
Solution Approach 2:
Different sections of the transmission line are designed with different local qualities - specifically different characteristic impedances. The first section has impedance Z1 optimized for one aspect of signal transmission, while the second section has impedance Z2 optimized for another aspect, allowing the system to achieve both noise immunity and improved bending capability through localized optimization.
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 enables efficient conversion of differential signals to single-ended signals with reduced space and cost, facilitating flexible winding and higher electrical performance in communications systems.
Implementation Method 1
a first microstrip, where the first microstrip includes a first balance signal connecting section, a first impedance matching section, and an unbalance signal connecting section that are sequentially connected, the first balance signal connecting section is configured to transmit a first component of a balance signal, and the unbalance signal connecting section is configured to transmit an unbalance signal
Data Source
AI summary
Embodiments of this application provide a balance-unbalance conversion apparatus. The apparatus includes an insulation substrate, a first microstrip, a second microstrip, and a conductive ground. The first microstrip includes a first balance signal connection section, a first impedance matching section, and an unbalance signal connecting section. The unbalance signal connecting section is configured to transmit an unbalance signal. The second microstrip includes a second balance signal connecting section, a second impedance matching section, and a ground section. The second balance signal connecting section is configured to transmit a second component of the balance signal. The ground section is configured to connect to a ground signal. The first microstrip, the second microstrip, and the conductive ground are all disposed on the insulation substrate, and a cross-sectional area of at least a part of the first microstrip and/or at least a part of the second microstrip is gradient.