RF Module Inductor Shielding Distance Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional radio frequency modules experience a deterioration in inductor Q-value and increased noise figure in the high-frequency band due to the presence of a shielding layer, which affects the noise figure (NF) performance.
Innovation Solution
The radio frequency module design includes a mounting board with low noise amplifiers and inductors positioned such that the distance between the inductors and the shielding layer is optimized, with the first inductor overlapping the first low noise amplifier and being further spaced from the shielding layer than the second inductor, reducing parasitic capacitance and coupling between inductors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a shielding layer is provided to cover components on the mounting board, then electromagnetic shielding performance is improved, but inductor Q-value deteriorates in high-frequency band due to proximity to the shielding layer
Solution Approach 1:
The patent applies local quality by providing different distance relationships between inductors and the shielding layer based on frequency requirements. Specifically, the first inductor (for high-frequency band) is positioned at a greater distance from the shielding layer compared to the second inductor (for low-frequency band), optimizing each inductor's performance for its designated frequency range while maintaining overall shielding effectiveness.
2Object-affected harmful factors
If a shielding layer is provided to cover components on the mounting board, then electromagnetic shielding performance is improved, but noise figure increases in high-frequency band due to increased line length between inductor and low noise amplifier
Solution Approach 1:
The patent optimizes the noise figure by locally adjusting the position of the first inductor for high-frequency operation. The first inductor is placed closer to the first low noise amplifier and positioned at a greater distance from the shielding layer, thereby minimizing the line length and reducing noise figure in the high-frequency band while maintaining shielding performance.
3Area of stationary object
If inductors are positioned closer to the shielding layer, then space utilization is improved, but parasitic capacitance increases causing Q-value deterioration
Solution Approach 1:
The patent changes the spatial parameter (distance from shielding layer) of the first inductor specifically for high-frequency operation. By increasing the distance between the first inductor and the shielding layer, the parasitic capacitance is reduced, thereby improving the Q-value of the first inductor in the high-frequency band while still utilizing the mounting board space efficiently through optimized layout.
Data Source
AI summary
In a radio frequency module, the first inductor is disposed on the first principal surface of the mounting board and located on the first reception path through which a first reception signal of a first frequency passes, on an input side of the first low noise amplifier. The second inductor is disposed on the first principal surface of the mounting board and located on the second reception path through which a second reception signal of a second frequency lower than the first frequency passes, on an input side of the second low noise amplifier. The radio frequency component is disposed between the first inductor and the second inductor. A distance between the first inductor and the shielding layer is greater than a distance between the second inductor and the shielding layer. The first inductor overlaps the first low noise amplifier in a thickness direction of the mounting board.