Hybrid Satellite MIMO Using Polarization Diversity Under Delay Mismatch
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Non-terrestrial networks face challenges in maintaining high performance due to the large and variable distance between ground-based base stations and satellites, which complicates accurate time synchronization and multi-antenna processing, leading to low data rates and reliability issues.
Innovation Solution
The implementation of a hybrid MIMO system using multiple satellites with antennas having different polarization angles, where each satellite performs multi-antenna diversity and MIMO processing, and the base station synchronizes and combines the signals from multiple satellites to enhance link budget and data rates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multi-antenna processing is performed via base station for multiple satellite antenna streams, then multi-antenna diversity gains can be achieved, but accurate time synchronization becomes difficult due to large and variable distances
Solution Approach 1:
The patent segments the MIMO processing function between satellite and base station. The satellite performs initial signal combining and preprocessing on multiple antenna streams, while the base station performs final MIMO processing. This segmentation allows each node to handle a manageable subset of the synchronization challenge, making accurate time synchronization feasible despite large and variable distances.
Solution Approach 2:
The satellite performs preliminary signal combining and preprocessing operations on multiple antenna streams before forwarding to the base station. This preliminary action reduces the complexity of time synchronization required at the base station, as the satellite has already aligned and combined the signals using its own timing references and buffer mechanisms.
2Productivity
If multiple antenna streams are transmitted via different non-terrestrial platforms, then link budget and data rates can be improved, but time synchronization becomes increasingly difficult to achieve
Solution Approach 1:
The satellite acts as an intermediary that receives signals from multiple ground antennas, performs initial combining and preprocessing, then forwards the combined stream to the base station. This intermediary role simplifies the synchronization problem by having the satellite handle the complex multi-stream alignment using its own timing infrastructure, rather than requiring perfect synchronization between all ground-based components.
Solution Approach 2:
The system segments the signal processing chain so that the satellite handles the time-consuming synchronization and combining operations for multiple antenna streams, while the base station focuses on final MIMO processing. This division allows high data rates to be achieved through multiple satellite antenna streams without requiring the base station to perform complex real-time synchronization.
3Adaptability or versatility
If existing UEs are used for satellite communication, then compatibility is maintained, but performance degrades due to high distance and increased power requirements
Solution Approach 1:
The patent merges signals from multiple satellite antenna streams through combining operations performed at the satellite and base station. This combining provides diversity gains that compensate for the path loss and performance degradation caused by the large distance between UEs and satellites, allowing existing UEs to maintain reliable communication without excessive power increases.
Solution Approach 2:
The system uses existing, mass-produced UEs with known performance characteristics rather than designing specialized high-performance satellite terminals. By combining multiple signal streams through the satellite MIMO system, the patent achieves reliable performance with off-the-shelf UEs that would be insufficient for single-stream satellite communication at these distances.
Data Source
AI summary
Method comprising receiving, by a first antenna, a first signal, and receiving, by a second antenna, a second signal. A feeder signal is forwarded to a base station, wherein the feeder signal is based on the first signal and the second signal. A polarization angle of the second antenna is different from a polarization angle of the first antenna.