Dynamic MBSFN Subframe Allocation for PDCCH Limited LTE Systems
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Solution Overview
Problem
Existing mobile and wireless telecommunication systems, such as LTE and 5G, face inefficiencies in managing PDCCH limited and non-PDCCH limited conditions, leading to suboptimal utilization of MBSFN subframes, which affects network performance and capacity.
Innovation Solution
An apparatus and method that dynamically adjust the percentage of subframes using unicast multimedia broadcast single frequency network (MBSFN) based on PDCCH limitations, switching user equipment (UEs) between transmission modes 9 and 4 to optimize PDCCH symbol usage, and adjust MBSFN usage accordingly to maximize network performance and capacity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the percentage of subframes using unicast MBSFN is increased to improve network capacity, then system throughput is improved, but PDCCH resource exhaustion occurs in PDCCH limited systems
Solution Approach 1:
The patent implements dynamic adjustment of the percentage of subframes using unicast MBSFN based on real-time PDCCH resource availability detection. The system transitions from static semi-statical allocation to dynamic configuration, adapting the MBSFN subframe percentage according to current system conditions to balance capacity improvement with PDCCH resource sustainability
Solution Approach 2:
The patent introduces a feedback mechanism where the system detects PDCCH resource usage conditions and uses this information to adjust the percentage of MBSFN subframes. The base station monitors PDCCH limited conditions and provides feedback through system information blocks to update UE configurations, creating a closed-loop control system that prevents PDCCH exhaustion while maximizing network capacity
2Productivity
If unicast data is transmitted over MBSFN subframes to improve resource utilization, then spectral efficiency is improved, but interference from CRS increases
Solution Approach 1:
The patent applies different transmission modes to different subframe types based on local conditions. Normal subframes use transmission mode 9 with CRS for reliable unicast transmission, while MBSFN subframes use transmission mode 4 without CRS to reduce interference. This local differentiation of transmission characteristics optimizes spectral efficiency while managing CRS interference in specific regions of the time-frequency resource grid
3Device complexity
If semi-statical allocation of MBSFN subframes is used to simplify system management, then device complexity is reduced, but network adaptability to changing conditions deteriorates
Solution Approach 1:
The patent transitions the system from semi-statical to dynamic allocation of MBSFN subframes. The percentage of subframes using unicast MBSFN is no longer fixed but is dynamically adjusted based on detected PDCCH resource availability. This dynamic approach enables the network to adapt to changing traffic conditions and resource availability while maintaining manageable complexity through automated detection and configuration updates
Data Source
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AI summary
Systems, methods, apparatuses, and computer program products for selective over the air reconfiguration of unicast MBSFN are provided. One method may include detecting whether a system is physical downlink control channel (PDCCH) limited. When it is detected that the system is physical downlink control channel (PDCCH) limited, the method may include reducing a percentage of subframes that are using unicast multimedia broadcast single frequency network (MBSFN). When it is detected that the system is not physical downlink control channel (PDCCH) limited, the method may include increasing the percentage of subframes that are using unicast multimedia broadcast single frequency network (MBSFN).