RFFE Dual Connectivity Signal Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless communication devices face challenges in efficiently processing dual-connectivity RF signals using both 4G LTE and 5G NR technologies, particularly in scenarios where signal frequencies are close or within the same frequency band, leading to potential intra-modulation distortion.
Innovation Solution
A radio frequency front end (RFFE) configuration with separate channels for LTE and NR signals, each with transmit and receive paths, utilizes antenna diversity to filter and amplify signals, reducing distortion by avoiding signal mixing and supporting simultaneous transmission and reception of both technologies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If separate channels are used for LTE and NR signals, then intra-modulation distortion is reduced, but device complexity increases
Solution Approach 1:
The RFFE is divided into separate channels - a first channel for LTE signals and a second channel for NR signals. Each channel has its own transmit path and receive path with dedicated filters and amplifiers, preventing signal mixing and reducing intra-modulation distortion while maintaining clear signal separation.
Solution Approach 2:
A signal splitter is introduced as an intermediary component that receives combined RF signals from antennas and directs them to appropriate channels. The splitter includes a first splitter for LTE signals and a second splitter for NR signals, enabling proper signal routing without direct mixing.
2Reliability
If antenna diversity is implemented for both LTE and NR, then signal reception quality improves, but device complexity increases
Solution Approach 1:
The antenna system is designed to serve multiple functions simultaneously. Antennas can receive both LTE and NR signals, and the same antenna can provide diversity reception for either technology. The RFFE channels are configured to handle multiple signal types through shared antenna resources, reducing the need for completely separate antenna systems.
Solution Approach 2:
The receive paths are segmented into first receive paths for LTE signals and second receive paths for NR signals. Each receive path includes dedicated filters and amplifiers that can process signals from shared antennas, enabling antenna diversity for both technologies without requiring separate dedicated antennas for each function.
3Adaptability or versatility
If simultaneous transmission of LTE and NR is supported, then dual-connectivity capability improves, but signal interference increases
Solution Approach 1:
The transmit paths are segmented into a first transmit path for LTE signals and a second transmit path for NR signals. Each path has dedicated power amplifiers and filters that prevent signal mixing, enabling simultaneous transmission of both technologies without mutual interference while maintaining clear spectral separation.
Solution Approach 2:
Signal splitters serve as intermediaries that receive combined RF signals and properly route them to respective channels. The first splitter handles LTE signals and the second splitter handles NR signals, preventing cross-channel interference and enabling simultaneous dual-connectivity operation.
Data Source
AI summary
A radio frequency front end (RFFE) is configured to support dual connectivity communications, in which two different radio access technologies such as LTE and NR are used simultaneously for uplink communications from a wireless communications device to a base station. The RFFE has two channels and two respectively associated antennas. The first channel transmits an NR signal from the first antenna. The second channel transmits an LTE signal from the second antenna. For reception, the first channel produces a main NR receive signal and LTE diversity signal. The second channel produces a main LTE receive signal and an NR diversity signal.