RRC Connection Setup Delay Reduction via Neighbor Cell Timer Comparison

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In cellular wireless communication systems, the existing methods for establishing an RRC connection do not effectively consider the varying response times across different cells, leading to significant delays, especially when the current cell has a high load and a neighboring cell with lower response time is available.

Innovation Solution

A wireless communication device obtains timer values for the maximum waiting time for an RRC connection setup from both the serving cell and a neighbor cell, calculates the difference, and if it exceeds a threshold, it either reselects the neighbor cell or reduces the waiting time for the serving cell, allowing for a more efficient connection setup by minimizing delays.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of time

If the wireless communication device requests an RRC connection towards the current serving cell without considering the maximum response time, then the connection setup procedure is simple, but the delay for connection setup increases significantly when the serving cell has high load

Engineering Contradiction:
Improveconnection setup delayVSAvoidcell selection complexity
Core Design Contradiction:
Loss of timeVSDevice complexity

Solution Approach 1:

The wireless communication device performs preliminary actions by obtaining timer values from multiple cells before initiating the RRC connection request. The device compares timer values from the serving cell and neighbor cells in advance, and proactively selects the cell with the shorter timer value, thereby avoiding delays that would occur if connection setup were initiated at a later stage with higher latency.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The invention changes the selection parameter for cell choice from traditional signal quality metrics alone to a combination of signal quality and timer values (maximum response time). By introducing timer values as a dynamic parameter, the device can adaptively select cells based on both signal conditions and expected response time, optimizing connection setup delay.

Inventive Principle:
Principle #35Parameter changes

2Productivity

If the wireless communication device waits for the maximum time specified by the serving cell, then it follows the standard procedure, but the user experiences significant delay when neighboring cells offer faster response

Engineering Contradiction:
Improveconnection establishment efficiencyVSAvoidwaiting time for response
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The invention introduces dynamic cell selection based on real-time timer value comparisons. Instead of statically waiting for the maximum time specified by the serving cell, the device dynamically evaluates timer values from both serving and neighbor cells, and adaptively switches to the cell with the shorter timer value, thereby optimizing the waiting time based on current network conditions.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The device skips the traditional waiting period by proactively selecting a neighbor cell with a shorter timer value before initiating the connection request. This allows the device to rush through the connection setup process by choosing a cell that is likely to respond faster, thereby reducing the overall establishment time.

Inventive Principle:
Principle #21Skipping (Rushing through)

3Loss of time

If the wireless communication device considers timer values from neighbor cells and performs reselection, then the connection setup delay is reduced, but the device complexity and processing requirements increase

Engineering Contradiction:
Improveresponse time differenceVSAvoidtimer comparison and reselection logic
Core Design Contradiction:
Loss of timeVSDevice complexity

Solution Approach 1:

The device performs partial cell reselection by comparing timer values only from a limited set of neighbor cells rather than all possible cells. This partial action approach reduces the computational burden while still achieving the benefit of selecting a faster-responding cell, balancing the trade-off between delay reduction and complexity increase.

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentEP3427518B1Radio resource control connection establishment
Publication Date: 2019.11.27 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
  • EP3427518B1 patent drawingFigure 1~2
  • EP3427518B1 patent drawingFigure 3a
  • EP3427518B1 patent drawingFigure 3b

AI summary

A wireless communication device (106) intends to request an RRC connection to initiate a voice call, initiate a data session or respond to paging. The wireless communication device (106) considers the maximum response time for the connection setup indicated by a serving cell (131) and compare to the maximum response (i.e. waiting) time for the connection setup indicated by a neighbour cell (121, 122). A long maximum response time may indicate a cell with high load. If the maximum response time indicated by a neighbour cell (121, 122) is significantly lower, the wireless communication device (106) may either reselect and request RRC connection from this neighbour cell (121, 122) instead or reduce the time to wait for a response from the serving cell (131) and reselect to the neighbour cell (121, 122) if there is no response from the serving cell within the reduced time.