Matched Duplexer Filters With Integrated Port Matching
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Solution Overview
Problem
Existing duplexer and multiplexer designs in radio communication systems suffer from high loss and large size due to the use of long PCB-based transmission lines, which are lossy and difficult to manufacture, especially in dual-band and multiband filters, making it challenging to meet low-level Tx path loss requirements and increasing costs.
Innovation Solution
The implementation of single-port-matched band pass filters (SPMBPF) and dual-port-matched band pass filters (DPMBPF) that integrate impedance matching directly into the filter design using the same materials and processes as the main filter parts, reducing the need for long transmission lines and allowing for configurations such as side-by-side, end-to-end, and stacked arrangements, thereby minimizing losses and size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If long PCB-based transmission lines are used to connect filters and match ports, then impedance matching is achieved, but transmission loss increases significantly
Solution Approach 1:
The patent combines the impedance matching function with the filter structure by integrating matching networks directly into the filter assembly. This merging eliminates the need for separate long transmission lines, thereby reducing transmission loss while maintaining impedance matching capability. The matching network is constructed using the same materials and processes as the filter, creating a unified structure that addresses both requirements simultaneously.
2Ease of operation
If carrier PCB and long transmission lines are used to combine filters, then port matching is achieved, but device size increases
Solution Approach 1:
The patent merges the port matching function with the filter structure itself, eliminating the need for separate carrier PCB and long transmission lines. The matching network is integrated directly into the filter assembly using the same materials and manufacturing processes, thereby achieving port matching while significantly reducing the overall device size and volume.
3Adaptability or versatility
If multiple single-band filters are combined with transmission lines to form common ports, then multiband filtering is achieved, but manufacturing complexity increases
Solution Approach 1:
The patent combines multiple single-band filters with integrated matching networks into a unified filter assembly. By using the same materials and manufacturing processes for both the filters and matching networks, the patent simplifies the manufacturing process while maintaining multiband filtering capability. This integrated approach reduces assembly steps and manufacturing complexity compared to traditional separate component approaches.
4Device complexity
If traditional duplexer design with separate transmission lines is used, then filter combination is achieved, but Tx path loss requirement cannot be met
Solution Approach 1:
The patent merges the matching network with the TX filter structure, eliminating the need for separate transmission lines that cause excessive loss. The integrated design uses the same materials and processes, creating a compact structure that maintains the necessary filter combination functionality while reducing Tx path loss to meet stringent requirements.
Data Source
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AI summary
Methods and apparatuses are provided for a matched band pass filter utilized in a duplexer or multiplexer. In one embodiment, the matched band pass filter includes a filter part and a port-matching part that is coupled to and in signal communication with the filter part. The filter part is configured to filter an RF signal and includes an input port. The port-matching part includes an output port. The port-matching part is configured to provide impedance matching through the output port.