Wireless Handover Delay Parameter for Temporary User Filtering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In hierarchical cellular networks, the high frequency of handovers between macrocells and small cells, particularly for temporary users who stay for short durations, creates a significant burden on macrocell base stations, as existing techniques fail to adequately suppress unnecessary handovers beyond addressing the ping-pong effect and assume uniform user mobility.
Innovation Solution
A method and apparatus that introduce a delay parameter to determine whether a handover criterion is satisfied for a specific time period, allowing temporary users to sustain connections with the macrocell instead of immediately handing over to small cells, thereby reducing the number of handovers by delaying handovers based on signal strength measurements and user terminal staying time data.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If handover is performed immediately when signal intensity of small scale cell exceeds threshold, then handover responsiveness is improved, but number of unnecessary handovers increases
Solution Approach 1:
The patent applies preliminary action by introducing a delay parameter T that is set in advance based on statistical analysis of user staying times. When a user terminal enters a small scale cell, handover is not performed immediately but is delayed by time T, allowing the system to preliminarily assess whether the user will stay long enough to justify handover. This resolves the contradiction by maintaining responsiveness (handover still occurs quickly when appropriate) while reducing unnecessary handovers (temporary users are filtered out by the delay mechanism).
Solution Approach 2:
The patent changes the parameter of handover timing by introducing a time delay parameter T. Instead of using a fixed threshold-based handover trigger, the system modifies the handover decision parameter to include a time component. The delay parameter T is dynamically determined based on statistical distributions of user staying times, transforming the handover criterion from purely signal-intensity-based to a time-integrated criterion that accounts for user mobility patterns.
2Productivity
If delay parameter is increased to suppress temporary user handovers, then number of handovers is reduced, but handover responsiveness deteriorates
Solution Approach 1:
The patent applies dynamics by making the delay parameter T adaptive rather than fixed. The system dynamically adjusts T based on the specific small scale cell context and user conditions. The delay parameter is determined through statistical analysis of staying time distributions for different cells, allowing the system to optimize the balance between reducing unnecessary handovers and maintaining responsiveness for each specific scenario. This dynamic adjustment resolves the contradiction by preventing both excessive delay and insufficient filtering.
3Device complexity
If existing handover techniques are used without delay parameter, then handover simplicity is maintained, but macrocell base station burden increases
Solution Approach 1:
The patent introduces an intermediary element - the delay parameter T - that mediates between the simple threshold-based handover trigger and the complex macrocell base station processing burden. By inserting this time-based filtering mechanism, the system reduces the number of handover requests that reach the macrocell base station without requiring complex processing logic. The delay parameter acts as a simple yet effective intermediary that filters out temporary users before they can generate unnecessary handover signaling traffic.
Data Source
AI summary
When a handover apparatus of a user terminal enters a small scale cell within a macrocell area in a state that it is connected to a macrocell, the handover apparatus acquires a delay parameter of the small scale cell and delays handover for a time period of the delay parameter of the small scale cell and determines handover to the small scale cell. Thereby, handover to the small scale cell for a temporal user of the small scale cell can be reduced.