Extended Access Barring for Delay-Tolerant MTC UEs
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Radio Access Network (RAN) overload occurs due to simultaneous access attempts from a large number of Machine Type Communication (MTC) User Equipment (UEs), leading to increased contention and power consumption for normal UEs during Random Access procedures.
Innovation Solution
Implementing Extended Access Barring (EAB) mechanisms that allow delay-tolerant MTC UEs to check for barring information immediately during the Random Access procedure, enabling them to stop the procedure if access is barred, and using different timer values for RRC connection establishment based on access causes, thereby controlling RAN overload.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If simultaneous access attempts from large number of MTC UEs are allowed, then network coverage and accessibility are improved, but RAN overload and contention increase
Solution Approach 1:
The patent segments UEs into two categories: delay-tolerant UEs and non-delay-tolerant UEs. Delay-tolerant UEs are subject to access barring checks that prevent them from initiating Random Access procedures when the cell is congested, while non-delay-tolerant UEs can access immediately. This segmentation resolves the contradiction by allowing comprehensive coverage while preventing overload from delay-tolerant traffic.
Solution Approach 2:
The patent implements preliminary access barring checks before UEs initiate Random Access procedures. The UE checks the access barring indicator in system information blocks before attempting to access the cell. If barred, the UE waits for a predetermined time before retrying. This preliminary action prevents overload by stopping potential access attempts before they consume RAN resources.
2Speed
If Random Access procedure is initiated by multiple UEs simultaneously, then connection establishment speed is improved, but power consumption and contention increase
Solution Approach 1:
The patent performs preliminary access barring checks before UEs initiate Random Access procedures. By checking the access barring indicator in advance, delay-tolerant UEs avoid initiating power-consuming Random Access procedures when the cell is congested, thereby reducing overall power consumption in the network while maintaining fast connection establishment for non-delay-tolerant UEs.
3Productivity
If access barring checks are performed, then RAN overload is reduced, but access delay for delay-tolerant UEs increases
Solution Approach 1:
The patent implements dynamic access control where the access barring indicator is broadcast in system information blocks and can be updated based on network conditions. When congestion is detected, the indicator bars delay-tolerant access; when conditions improve, access is permitted. This dynamic approach optimizes the balance between preventing RAN overload and minimizing access delay for delay-tolerant UEs.
Data Source
AI summary
A method and apparatus are disclosed to prevent RAN (Radio Access Network) overload. In one embodiment, the method comprises initiating, at a User Equipment (UE), a RRC (Radio Resource Control) connection establishment procedure to establish a RRC connection to a cell. The method also comprises initiating, at the User Equipment (UE), a Random Access procedure due to a transmission of a RRCConnectionRequest message for the RRC connection establishment procedure, wherein an establishment cause in the RRCConnectionRequest message is set to delay tolerant access, and the UE stops the Random Access procedure if the UE considers access to the cell as barred based on barring information for delay tolerant access of the cell.