Layered Mobility for Small Cell Handover Latency Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, especially in LTE networks with small cells, the realization of handovers and dynamic resource management is hindered by communication delays and high signaling overhead, particularly when the number of small cells is high, leading to inefficient mobility management and resource allocation.
Innovation Solution
Implementing layered mobility with dual-connectivity, where small cell mobility is managed independently of the macro cell layer, using separate Radio Network Temporary Identifiers (RNTIs) and streamlined Scheduling Request mechanisms to optimize handovers within small cell clusters, reducing the need for traditional RACH procedures and allowing for efficient resource allocation and management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional handover procedures are used in small cell networks, then mobility management is achieved, but signaling overhead and latency increase significantly
Solution Approach 1:
The patent segments mobility management into two independent layers: macro cell layer mobility and small cell layer mobility. Each layer has its own RNTI and handover procedures, allowing small cell handovers to occur independently without involving the macro cell layer, thereby reducing signaling overhead and latency.
Solution Approach 2:
The patent introduces a small cell layer RNTI as an intermediary identifier that enables direct communication and handover management between small cells and user equipment, bypassing the need for traditional RACH procedures through the macro cell layer.
2Reliability
If traditional RACH procedures are used for small cell handovers, then connection management is maintained, but signaling overhead increases
Solution Approach 1:
The patent extracts the small cell layer handover management from the traditional RACH procedure framework. By introducing a separate small cell layer RNTI and streamlined scheduling request mechanism, the system removes the overhead of traditional RACH procedures while maintaining connection management reliability.
Solution Approach 2:
The patent implements preliminary configuration of small cell layer RNTIs and scheduling request resources before handovers occur. This pre-configuration allows user equipment to perform handovers within the small cell layer without needing to initiate traditional RACH procedures, thereby reducing signaling overhead.
3Productivity
If separate RNTIs are implemented for small cell layer, then mobility management efficiency improves, but system complexity increases
Solution Approach 1:
The patent adds a new dimension to the RNTI system by introducing a small cell layer RNTI that operates independently from the macro cell layer RNTI. This dimensional separation allows mobility management to occur in parallel across different layers without interfering with each other, improving efficiency while managing complexity through clear layer separation.
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Apparatuses and methods for providing layered mobility are provided. Small cell eNBs belong to a cluster of local area base stations. A source eNB has a connection with user equipment having a first identity related to the connection and receives from the user equipment a request 702 to send a scheduling request to another local area eNB of the cluster, the request comprising a list of target candidate eNBs. The source eNB determines (704) suitable target eNB(s) from the list and resources for sending a scheduling request; and transmits The target eNB receives (708) a scheduling request from user equipment allocates and sends (710) communication resources to the user equipment and associates the first identity to the connection with the user equipment.