Balanced Amplifier Bypass Branch Without Switch Path Loss
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing balanced amplifying devices with bypass branches suffer from performance limitations due to the presence of switches, which affect return loss, noise figure, reverse isolation, and gain, especially since the signal passes through switches in both active and bypass modes, and the choice of switches is limited by the need for high reverse isolation and stability without a power supply.
Innovation Solution
A balanced amplifying device is designed with a bypass branch connected to a port of a coupling/splitting unit connected to an electrical termination element, allowing the bypass branch to supply signals directly to the output without passing through switches in normal mode, thereby enhancing performance by eliminating switch-induced losses and improving return loss, noise figure, and gain.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If switches are used to enable bypass mode in existing balanced amplifying devices, then bypass functionality is achieved, but the signal passes through switches in both bypass and active modes which degrades performance parameters like return loss, noise figure, reverse isolation and gain
Solution Approach 1:
The invention extracts the bypass branch from the main signal path in normal operating mode. The bypass branch is connected to a port of the first coupling/splitting unit that is normally connected to an electrical termination element, allowing the bypass functionality to be isolated and activated only when needed, without interfering with the main amplifying path during normal operation.
Solution Approach 2:
The invention uses a switching arrangement as an intermediary to selectively connect the second port of the first coupling/splitting unit to either the electrical termination element or the bypass branch. This mediator enables smooth transition between normal and bypass modes without degrading signal quality in either mode.
2Adaptability or versatility
If switches are implemented at the input of the amplifier to enable bypass mode, then bypass operation is possible, but additional insertion loss, stability problems and limited MTBF are introduced
Solution Approach 1:
The bypass branch is extracted and connected to the second port of the first coupling/splitting unit, which is normally terminated. This positioning allows the bypass functionality to be activated without placing switches in the critical input path of the amplifier, thereby avoiding insertion loss and stability issues.
3Reliability
If high reverse isolation switches are used to ensure stability in bypass mode, then self oscillation immunity is achieved, but the choice of switches is limited and performance is compromised due to lack of power supply
Solution Approach 1:
A switching arrangement is used as an intermediary to selectively connect the second port to either the termination element or bypass branch. This mediator provides the necessary reverse isolation and stability control without requiring the bypass switches to operate without power supply, thus expanding switch selection flexibility.
Data Source
AI summary
A balanced amplifier includes a bypass branch (19), termination elements (TE1, TE2) and an amplifying section (10). The section (10) includes amplifiers (A1, A2), first coupling/splitting unit (14) having a first input signal receiving port (14a), a second port (14b) connected to a termination element (TE1), a third port (14c) connected to a first amplifier (A1), and a fourth port (14d) connected to a second amplifier (A2). The section (10) also includes second coupling/splitting unit (16) having a first port (16a) connected to first amplifier (A1), a second port (16b) connected to second amplifier (A2) and a third port (16c) connected to a termination element (TE2). The second coupling/splitting unit (16) combines signals from amplifiers (A1, A2) as output signals on a fourth port (16d) for supply to a signal output (O). The branch (18) is connected to the second port (14b) of the first coupling/splitting unit (14) and provides bypass signals to output (O).