Linear Beam Sweeping with Adaptive Beam Width for High-Speed Trains
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
5G-NR systems face challenges in providing uniform beam coverage and efficient mobility management for high-speed train scenarios due to non-uniform beam coverage resulting from linear beam sweeping, which is exacerbated by the use of directional antennas and advanced beamforming techniques, leading to reduced beam coverage and time constraints for beam detection.
Innovation Solution
Adapting the Half-Power Beam Width (HPBW) of RRH antenna arrays by widening or narrowing based on path loss differences between beams to ensure equal segment lengths and maintain link quality, using techniques to measure beam coverage along the trajectory and adjust HPBWs dynamically.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If linear beam sweeping is used in high-speed train scenarios, then the system can cover the linear trajectory of the train, but the beam coverage becomes non-uniform due to different beam radii at different positions
Solution Approach 1:
The patent applies local quality by configuring different beam radii for different beams in the sweep based on their specific positions and path loss characteristics. Instead of using identical beams throughout, each beam is tailored to its local conditions along the linear trajectory, with beam radius adjusted according to the distance from the gNB and the corresponding path loss, thereby achieving uniform coverage along the train's path.
Solution Approach 2:
The patent implements parameter changes by dynamically adjusting the beam radius parameter for each beam in the sweep. The beam radius is calculated based on the path loss difference between beams, specifically using the formula: beam radius = base beam radius × exp(path loss difference / (2 × path loss factor)). This parameter adjustment ensures that beams with higher path loss (further positions) have larger radii to compensate for the reduced signal strength, maintaining uniform coverage.
2Reliability
If directional antennas and advanced beamforming techniques are used, then link quality is improved, but beam coverage is reduced leading to time constraints for beam detection
Solution Approach 1:
The patent adjusts the beam radius parameter to balance link quality and detection time. By increasing the beam radius for beams with higher path loss, the system maintains sufficient coverage area along the trajectory, thereby extending the dwell time available for beam detection and mobility management procedures while still utilizing directional antennas for maintaining link quality through beamforming.
3Ease of manufacture
If identical beams are used in linear beam sweeping, then the configuration is simple, but beam coverage becomes non-uniform due to varying distances from the gNB
Solution Approach 1:
The patent transitions from using identical beams to using locally optimized beams. Each beam is configured with a specific radius tailored to its position along the linear trajectory and its corresponding path loss characteristics. This local quality approach ensures uniform coverage along the train's path while maintaining practical configurability through automated calculation of beam parameters based on path loss differences.
Solution Approach 2:
The patent systematically changes the beam radius parameter across different beams in the sweep. The beam radius is calculated as: beam radius = base beam radius × exp(path loss difference / (2 × path loss factor)). This parameter change ensures that beams at greater distances (with higher path loss) have larger radii to compensate for signal attenuation, thereby achieving uniform coverage despite the increased configuration complexity.
Data Source
AI summary
There are provided measures for improvement of linear beam sweeping in high speed scenarios. Such measures exemplarily comprise setting a second beam width characteristic of a second beam of a beam sweep, wherein said setting includes calculating said second beam width characteristic based on a first beam width characteristic of a first beam of said beam sweep and a ratio between a first path loss of said first beam between an antenna and a first position at a linear trajectory to be covered by said beam sweep and a second path loss of said second beam between said antenna and a second position at said linear trajectory.