Dynamic Random Access Channel Configuration Selection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional wireless communication systems employ a single random access channel configuration for all mobile devices within a cell, leading to unnecessary overhead for devices closer to the base station, as the configuration is optimized for worst-case scenarios at the cell edge.

Innovation Solution

Mobile devices measure radio link characteristics, such as pathloss, and compare them to thresholds provided by the base station to dynamically select an appropriate random access channel configuration from a set of formats, reducing overhead by using shorter formats for closer devices and longer formats for farther devices.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a single random access channel configuration optimized for cell edge devices is used for all devices, then devices at the cell edge achieve adequate performance, but devices closer to the base station experience unnecessary overhead and resource waste

Engineering Contradiction:
Improverandom access performance for cell edge devicesVSAvoidoverhead for devices closer to base station
Core Design Contradiction:
ReliabilityVSLoss of energy

Solution Approach 1:

The patent applies local quality by allowing different mobile devices to use different random access channel configurations based on their specific location and pathloss characteristics. Devices closer to the base station use shorter, less resource-intensive formats, while devices at the cell edge use longer formats optimized for their conditions, rather than forcing all devices to use a single configuration optimized for the worst case.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent implements dynamics by enabling mobile devices to dynamically select from multiple random access channel configurations based on real-time measurements of radio link characteristics such as pathloss. The selection is not static but adapts to the device's specific conditions, allowing the system to optimize resource usage based on actual rather than worst-case scenarios.

Inventive Principle:
Principle #15Dynamics

2Reliability

If longer random access formats are used for all devices, then cell edge devices achieve reliable connection, but overall channel utilization efficiency decreases

Engineering Contradiction:
Improveconnection reliability for cell edge devicesVSAvoidchannel utilization efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent enables each mobile device to select a random access channel configuration appropriate to its specific location and channel conditions. Devices with good signal quality use shorter formats that consume fewer resources, while devices at the cell edge use longer formats that ensure reliable connection, thereby optimizing overall channel utilization while maintaining reliability where needed.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent changes the parameters of the random access channel configuration (such as format length, cyclic prefix duration, guard time) based on the mobile device's measured pathloss and distance from the base station. This parameter adaptation allows the system to match resource allocation to actual needs, improving both reliability and efficiency.

Inventive Principle:
Principle #35Parameter changes

3Loss of energy

If dynamic selection of random access configurations is implemented, then resource efficiency improves for devices closer to base station, but system complexity increases

Engineering Contradiction:
Improveoverhead reduction for devices closer to base stationVSAvoidcomplexity of random access configuration selection
Core Design Contradiction:
Loss of energyVSDevice complexity

Solution Approach 1:

The patent reduces complexity by having the base station pre-configure multiple random access channel formats with different characteristics (short, medium, long) and provide configuration information to mobile devices in advance. Devices can then select from these pre-defined options based on simple pathloss measurements, rather than requiring complex real-time optimization algorithms.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent enables mobile devices to autonomously select their own random access channel configuration based on their measured radio link conditions and the configuration information provided by the base station. This self-service approach eliminates the need for complex network-side control and coordination, simplifying the overall system while maintaining efficiency.

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP2462774B1Dynamic selection of random access channel configurations
Publication Date: 2020.04.29 QUALCOMM INC
  • EP2462774B1 patent drawingFigure 1
  • EP2462774B1 patent drawingFigure 2
  • EP2462774B1 patent drawingFigure 3

AI summary

Systems and methodologies are described that facilitate dynamic selection of a random access channel configuration. Typically, a single random access channel configuration is utilized throughout a cell; however, the configuration employed, while appropriate for some mobile devices within the cell, can introduce unnecessary overhead for other mobile devices. A mobile device can measure a characteristic of a radio link between the mobile device and a base station. The measurement can be compared to a set of thresholds provided by the base station. Based upon the comparison, a random access channel configuration can be selected from a set of formats. The selected configuration can be utilized to initiate random access procedures.