Random Access Request Feedback Mechanism for Collision Avoidance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional mobile communication systems face issues with erroneous determination of random access request receipt by the radio base station, leading to processing delays and resource wastage due to collisions when multiple mobile stations transmit signals simultaneously.
Innovation Solution
A mobile communication system where the mobile station transmits a random access request with mobile station information through a predetermined radio resource, and the radio base station responds with a notification including the allocated radio resource, allowing the mobile station to acknowledge successful receipt and avoid collisions by changing transmission resources if necessary.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple mobile stations transmit random access requests simultaneously using the same RACH resource, then the transmission efficiency is improved, but collision occurs leading to erroneous determination of receipt status
Solution Approach 1:
The base station feeds back mobile station information (such as preamble sequence or time resource) in the random access response to enable the mobile station to verify whether its transmission was successfully received. This feedback mechanism allows the mobile station to distinguish between successful and unsuccessful transmissions, resolving the erroneous determination problem caused by simultaneous transmissions.
Solution Approach 2:
The patent introduces mobile station information as an intermediary element that is embedded in the random access response. This intermediary carries identification data that allows the mobile station to verify receipt status without directly observing the collision state, thereby resolving the uncertainty caused by simultaneous transmissions.
2Reliability
If the mobile station increases transmission power to ensure receipt by the base station, then the reliability of transmission is improved, but the collision probability increases when multiple stations transmit simultaneously
Solution Approach 1:
By providing feedback containing mobile station identification information, the system allows mobile stations to verify whether their transmissions were successfully received regardless of power level. This eliminates the need to increase power solely for reliability, as the feedback mechanism provides certainty about transmission success.
Solution Approach 2:
The patent changes the parameter being verified from transmission power level to mobile station information matching. Instead of relying on power level as an indicator of successful transmission, the system verifies whether the mobile station information in the response matches the transmitted preamble, providing accurate receipt confirmation independent of power considerations.
3Reliability
If the mobile station uses power ramping to gradually increase transmission power, then the transmission reliability is improved, but the processing delay increases due to erroneous determination
Solution Approach 1:
The feedback mechanism provides immediate verification of transmission success through mobile station information matching in the random access response. This eliminates the need for multiple power ramping attempts and the associated delays, as the mobile station can immediately determine whether its transmission was successful based on the feedback content.
Solution Approach 2:
The base station prepares the random access response with mobile station information in advance, allowing the mobile station to verify receipt status immediately upon receiving the response. This preliminary preparation of verification information eliminates the need for iterative power ramping and waiting periods, reducing processing delay.
4Ease of operation
If the mobile station transmits random access requests using predetermined radio resources, then the ease of operation is improved, but resource wastage occurs due to collisions
Solution Approach 1:
The feedback mechanism allows mobile stations to verify whether their use of predetermined resources was successful. When collisions occur, the feedback indicates failure, allowing the mobile station to retry with different parameters. This maintains the simplicity of using predetermined resources while reducing waste by enabling efficient retry strategies based on feedback information.
Solution Approach 2:
When collisions are detected through feedback analysis, the system discards the failed transmission attempt and recovers by initiating a retry with modified parameters (such as different preamble or time resource). This approach maintains the simplicity of predetermined resource allocation while minimizing resource wastage through efficient recovery from collision events.
Data Source
Figure 1
Figure 2~3B
Figure 4
AI summary
A packet communication method according to the present invention includes: transmitting, at a mobile station, a random access request that Includes mobile station information assigned to the mobile station, to a radio base station through a random access channel allocated to a predetermined radio resource; receiving, at the radio base station, the random access request from the mobile station; and transmitting, at the radio base station, a random access response signal that notifies the receipt of the random access request and includes the mobile station information, to the mobile station through a downlink shared control channel corresponding to the random access channel.