Fast Handover in Cross-Sector Mobile Scenarios
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In mobile communication systems, particularly in LTE, fast-speed user equipment experiences call drops during handover in cross-sector scenarios due to the time-consuming process of detecting adjacent cell identities, which are obscured by sectored beam forming, leading to delayed detection and increased call drop rates.
Innovation Solution
A method for fast handover that involves blind measurements of additional cells with the same cell group ID as the serving cell, allowing for quicker detection and measurement without relying on primary cell detection, thereby reducing the time required for handover and minimizing call drops.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If primary cell detection is used to detect adjacent cells, then cell identity detection is performed, but the detection time is too long causing call drops in fast-speed scenarios
Solution Approach 1:
The patent applies preliminary action by performing blind measurements of additional cells with the same cell group ID as the serving cell before the actual handover is needed. This allows the mobile device to pre-identify and measure potential target cells in advance, so when handover becomes necessary, the device already has measurement data ready, significantly reducing the handover time and preventing call drops in fast-speed scenarios.
2Area of stationary object
If sectored beam forming is used to serve adjacent cells, then cell coverage is provided, but the beam is not visible to the mobile device making cell-id detection difficult
Solution Approach 1:
The patent uses blind measurement as an intermediary mechanism to detect adjacent cells whose beams are not directly visible to the mobile device. Instead of relying on direct signal detection from sectored beams, the device performs blind measurements on cells with the same cell group ID, effectively mediating the detection process to overcome the visibility limitation imposed by sectored beam forming.
3Adaptability or versatility
If cell search procedure is performed to detect cell identities, then handover is enabled, but the process is time-consuming resulting in call drops
Solution Approach 1:
The patent performs preliminary blind measurements of additional cells with the same cell group ID before the actual handover is needed. This preliminary action allows the mobile device to pre-identify and measure potential target cells, so when handover becomes necessary, the device already has measurement data ready, significantly reducing the handover time and preventing call drops in fast-speed scenarios.
4Speed
If additional cells with same cell group ID are measured blindly, then handover speed is improved, but measurement complexity increases
Solution Approach 1:
The patent applies local quality by focusing blind measurements only on additional cells with the same cell group ID as the serving cell, rather than measuring all possible cells. This localized approach to measurement maintains measurement efficiency while enabling faster handover, as the device only needs to measure cells that are likely to be relevant for handover decisions in the current sector context.
Data Source
AI summary
A method for handover in a mobile communication system, wherein cell search is performed by determining cell identities based on cell identity information transmitted within downlink data is provided. The cell power of cells detected by cell search is measured. Moreover, the cell power of an additional cell is measured, the additional cell having a cell identity that is related to a cell identity of a cell detected by cell search in that the additional cell and the cell detected by cell search are adjacent cells. The method is applicable in cross-sector scenarios avoiding call drops due to lengthy cell detection.