Dynamic Random Access Preamble Assignment for Radio Communication Systems

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing random access procedure using dedicated preambles in radio communication systems faces delays due to either long or short assignment periods, where a long period leads to occupied preamble numbers and a short period results in undetected preambles, causing retransmissions and delays in non-contention based random access.

Innovation Solution

A radio communication system that assigns random-access-signal identification information with a dynamically determined assignment period based on radio channel quality, allowing for longer retransmissions when channel quality is poor and shorter periods when it's good, and includes an extension mechanism to prevent unnecessary reassignment and optimize preamble usage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a long assignment period is used for dedicated preamble numbers, then the reliability of random access is improved, but the productivity of preamble number allocation deteriorates due to occupied preamble numbers

Engineering Contradiction:
Improvereliability of random accessVSAvoidpreamble number allocation efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent applies dynamics by making the assignment period variable rather than fixed. The base station determines different assignment periods based on radio channel quality - longer periods for poor quality channels and shorter periods for good quality channels. This dynamic adjustment resolves the contradiction by optimizing both reliability and productivity according to actual channel conditions.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the parameter of assignment period length based on radio channel quality. By adjusting this parameter dynamically, the system achieves higher reliability when needed (poor channel conditions) while maintaining high productivity when possible (good channel conditions), thus resolving the contradiction between these two opposing requirements.

Inventive Principle:
Principle #35Parameter changes

2Productivity

If a short assignment period is used for dedicated preamble numbers, then the productivity of preamble number allocation is improved, but the reliability of random access deteriorates due to undetected preambles causing retransmissions

Engineering Contradiction:
Improvepreamble number allocation efficiencyVSAvoidreliability of random access
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The system dynamically adjusts the assignment period based on radio channel quality measurements. When channel quality is good, shorter assignment periods are used to improve productivity. When channel quality deteriorates, the assignment period is extended to maintain reliability, preventing undetected preambles and unnecessary retransmissions.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The assignment period parameter is changed according to radio channel quality conditions. This parameter adjustment allows the system to optimize the trade-off between productivity and reliability - using short periods for high productivity when channels are good, and long periods for high reliability when channels are poor.

Inventive Principle:
Principle #35Parameter changes

3Device complexity

If fixed assignment periods are used, then the device complexity is reduced, but the adaptability to different radio channel conditions deteriorates

Engineering Contradiction:
Improveassignment period management complexityVSAvoidadaptability to channel conditions
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent implements dynamic adjustment of assignment periods based on radio channel quality. The base station measures channel quality and automatically determines appropriate assignment periods, providing adaptability to different channel conditions while keeping the implementation relatively simple through standardized measurement and determination procedures.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The assignment period parameter is adapted to different radio channel conditions by changing its value based on measured quality metrics. This allows the system to be versatile across different channel conditions without requiring complex manual configuration, achieving adaptability through automated parameter adjustment.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP2192798B1Radio communication system, base station device, mobile station device, and random access method
Publication Date: 2019.03.06 SHARP KK
  • EP2192798B1 patent drawingFigure 1
  • EP2192798B1 patent drawingFigure 2
  • EP2192798B1 patent drawingFigure 3

AI summary

A radio communication system includes a base station device and a plurality of mobile station devices which radio-communicate with the base station device. The base station device allocates random access signal identifiers for identifying random access signals to the mobile station devices and decides an allocation period for each of the random access signal identifiers used by the mobile base stations. During the allocation period, each of the mobile station devices transmits a random access signal corresponding to the allocated random access signal identifier. Thus, it is possible to suppress a delay until the random access procedure using a dedicated preamble is complete.