RF Switching Circuit With Shared Filtering and Duplexer Bypass
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing radio frequency switches with multiple switching elements and low pass filters between antenna and external connection ports result in increased circuit size, necessitating a solution that allows for switching between signal paths with and without a duplexer while minimizing circuit size.
Innovation Solution
A communication circuit configuration that includes a duplexer and a signal path without a duplexer, utilizing switches and variable filters to switch between transmission paths, allowing signal filtering in both paths without enlarging the circuit.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If low pass filters are provided between each antenna port and switching elements, then signal filtering is improved, but circuit size increases
Solution Approach 1:
A single low pass filter is designed to serve multiple antenna ports (first antenna port, second antenna port, and external connection port) through switching elements. The filter is connected to a common node that can switch between different ports, allowing one filter to perform the filtering function for all ports rather than requiring separate filters for each port.
Solution Approach 2:
The patent merges the filtering function across multiple signal paths by providing a single low pass filter that handles signals from multiple antenna ports and the external connection port. The switching elements enable this single filter to be shared across different signal paths, combining what would traditionally require multiple separate filters into one unified filtering solution.
2Adaptability or versatility
If multiple switching elements are provided to enable switching between signal paths with and without duplexer, then signal path flexibility is improved, but device complexity increases
Solution Approach 1:
The switching elements are designed to perform multiple functions: they switch between signal paths with and without the duplexer, and they also enable a single low pass filter to serve multiple antenna ports. This multi-functionality reduces the overall complexity by making each switching element do more than one thing.
Solution Approach 2:
The patent employs dynamic switching between different signal path configurations (with duplexer and without duplexer) based on operational requirements. The switching elements can dynamically reconfigure the signal flow to adapt to different transmission modes, enabling flexible adaptation without permanently fixing the circuit architecture.
Data Source
AI summary
A communication circuit includes a transmission terminal to which a transmission signal is supplied, a first duplexer that has a transmission node, a reception node, and a common node, a first filter that has a first end part electrically connected to the common node of the first duplexer and a second end part electrically connected to an antenna terminal, a first auxiliary output terminal that outputs the transmission signal to an external circuit, an inductor that is part of a second filter and has a first end part and a second end part that is electrically connected to the first auxiliary output terminal, and a first switch that switches the electrical connection destination of the transmission terminal between the transmission node of the first duplexer and the first end part of the inductor.