Split Isolation RFE Architecture Reducing Diplexer Size
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The miniaturization of electronic devices has been hindered by the large size and weight of traditional Radio Frequency Electronics (RFE) components, particularly waveguide diplexers, which are critical for achieving sufficient isolation between transmitter and receiver in full duplex transceivers, such as those used in the Common Data Link (CDL) program.
Innovation Solution
The implementation of a split isolation RFE architecture, where significant filtering is moved from the diplexer to before and after the power amplifier and low noise amplifier, allowing for reduced rejection requirements on the diplexer, enabling the use of smaller and lighter filter solutions, such as cavity filters, and providing flexibility in filter placement to improve link margin and reduce size and weight.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If waveguide diplexer is used to achieve sufficient isolation between transmitter and receiver, then isolation performance is improved, but size and weight of RFE increase significantly
Solution Approach 1:
The patent segments the filtering function from the diplexer by introducing separate transmit and receive filters. The diplexer's rejection requirement is reduced from needing to provide all isolation to only providing transmit-to-receive isolation, while separate filters handle the remaining isolation requirements. This segmentation allows each component to be optimized independently, enabling smaller, lighter filters to replace the large waveguide diplexer.
Solution Approach 2:
The patent changes the isolation parameter distribution across different components. Instead of requiring the diplexer to provide 120 dB or more of isolation, the system distributes isolation requirements: the diplexer provides transmit-to-receive isolation, while separate transmit and receive filters provide additional isolation to achieve the total required isolation performance. This parameter redistribution enables use of smaller, lighter filter technologies.
2Reliability
If waveguide diplexer is used to achieve sufficient isolation between transmitter and receiver, then isolation performance is improved, but volume of RFE increases significantly
Solution Approach 1:
The patent segments the filtering function from the diplexer by introducing separate transmit and receive filters. The diplexer's rejection requirement is reduced from needing to provide all isolation to only providing transmit-to-receive isolation, while separate filters handle the remaining isolation requirements. This segmentation allows each component to be optimized independently, enabling smaller, lighter filters to replace the large waveguide diplexer.
3Reliability
If filtering is concentrated in the diplexer to achieve sufficient isolation, then isolation performance is improved, but device complexity increases
Solution Approach 1:
The patent segments the filtering function from the diplexer by introducing separate transmit and receive filters. The diplexer's rejection requirement is reduced from needing to provide all isolation to only providing transmit-to-receive isolation, while separate filters handle the remaining isolation requirements. This segmentation allows each component to be optimized independently, enabling smaller, lighter filters to replace the large waveguide diplexer.
Data Source
AI summary
A system and method for designing a full duplex communications transceiver to enable a reduction in isolation between a transmit signal and a receive signal at a diplexer is disclosed. An RFE transmit filter attenuation level can be determined to be sufficient to attenuate a noise power of the transmitter below a thermal noise floor of the power amplifier. A minimum diplexer transmit filter attenuation level can be calculated to attenuate noise power output from the power amplifier in the receive band to a level below a noise floor of the receiver.