Multi-Band Filter Module With Switchable Ground Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In filter modules with multiple frequency bands, signal interference occurs due to close proximity of filters with different pass bands, leading to deteriorated attenuation characteristics, which is challenging to address while maintaining miniaturization.
Innovation Solution
The implementation of switchable ground connections between filters and their respective input/output terminals, allowing for time-division communication and ensuring that only the active filter's signal path is grounded, thereby reducing interference and maintaining a compact design.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If multiple filters with different pass bands are arranged adjacent to each other on the same substrate to reduce size, then miniaturization is achieved, but signal interference occurs and attenuation characteristics deteriorate
Solution Approach 1:
The patent applies preliminary action by pre-establishing ground connection paths through switches before signals are transmitted. The switches are configured to connect specific wires to ground in advance based on which filter is currently active, preventing signal interference before it occurs. This proactive grounding approach ensures that even when filters are arranged adjacently, their signal paths are isolated through pre-configured ground connections.
Solution Approach 2:
The patent implements dynamics by making the ground connections dynamic rather than fixed. Switches are used to dynamically connect or disconnect wires from ground based on which filter is currently in use. This dynamic reconfiguration allows the same physical layout to support multiple frequency bands without interference, as the grounding topology changes according to operational requirements.
2Reliability
If the number of ground terminals is increased to suppress deterioration of attenuation characteristics, then signal isolation is improved, but the substrate size increases
Solution Approach 1:
The patent applies universality by making existing ground terminals serve multiple functions. Instead of adding dedicated ground terminals for each filter, the same ground terminals are shared across different filters through dynamic switching. The switches enable a single ground terminal to be connected to different wires at different times, allowing one ground terminal to provide isolation for multiple filters sequentially, thus reducing the total number of ground terminals needed.
Solution Approach 2:
The patent implements parameter changes by dynamically altering the electrical connection state between wires and ground terminals. The switches change the connectivity parameters (connected or disconnected) based on operational mode, allowing the same physical infrastructure to provide different isolation configurations as needed. This parameter switching enables adequate signal isolation without requiring additional ground terminals.
Data Source
AI summary
A filter module includes a filter provided on a path connecting an input/output terminal and an input/output terminal, a filter provided on a path connecting an input/output terminal and an input/output terminal, a switch that switches between electrical connection and electrical disconnection between a wire connected to the input/output terminal and a ground, and a switch that switches between electrical connection and electrical disconnection between a wire connected to the input/output terminal and the ground. When the wire and the ground are electrically connected by the switch, the wire and the ground are electrically disconnected by the switch, and when the wire and the ground are electrically connected by the switch, the wire and the ground are electrically disconnected by the switch.