Inter-cell Interference Coordination via Almost Blank Subframes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In mobile communication systems, especially in heterogeneous environments with pico cells and macro cells, existing inter-cell interference coordination techniques are inefficient due to high interference between base stations, particularly in LTE-Advanced environments where pico cells with low transmission power coexist with macro cells of high transmission power, necessitating a time-domain interference control method.
Innovation Solution
The proposed solution involves a resource management method that includes transmitting an Almost Blank Subframe (ABS) set from a first base station to a second base station, along with a reference resource configuration for channel measurement and Radio Link Monitor/Radio Resource Measurement (RLM/RRM) for scheduling terminals in subframes selected from the ABS set, enhancing time domain eICIC through static and dynamic time resource allocation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If time domain eICIC is implemented with ABS set transmission, then inter-cell interference coordination is improved, but system complexity increases due to additional signaling and configuration requirements
Solution Approach 1:
The patent segments the time domain into Almost Blank Subframes (ABS) and non-ABS subframes, creating distinct time resources for different interference scenarios. This segmentation allows the system to manage interference by allocating specific time slots where macro cells transmit with reduced power while pico cells can serve their users, thereby reducing inter-cell interference without requiring complex continuous coordination mechanisms.
Solution Approach 2:
The patent implements preliminary configuration where the eNB configures the ABS pattern and transmits this information to the pico eNB before the actual data transmission begins. This preliminary setup allows the pico cell to prepare its scheduling decisions in advance based on the known ABS pattern, reducing the need for real-time complex signaling and coordination during data transmission.
2Manufacturing precision
If ABS set and reference resource configuration are transmitted between base stations, then scheduling accuracy is improved, but information transmission overhead increases
Solution Approach 1:
The patent designs the ABS set and reference resource configuration to serve multiple functions: they provide timing information for channel measurement, define resources for Radio Link Monitor (RLM), and establish scheduling boundaries for data transmission. By making this single configuration message multi-functional, the system achieves high scheduling accuracy without proportionally increasing information overhead.
Solution Approach 2:
The patent utilizes parameter changes in the configuration message, where the same ABS set information can be interpreted differently based on the intended purpose (channel measurement vs. scheduling). The system changes the interpretation parameters of the transmitted information to extract different types of scheduling accuracy requirements without transmitting separate messages for each function.
3Object-affected harmful factors
If pico cell schedules terminals only in ABS subframes, then interference reduction is achieved, but resource utilization efficiency decreases
Solution Approach 1:
The patent implements dynamic scheduling where the pico cell can flexibly allocate resources in both ABS and non-ABS subframes based on real-time channel conditions and interference levels. The system dynamically adjusts the scheduling decisions by monitoring actual interference measurements during ABS subframes and using this feedback to optimize resource allocation, allowing the pico cell to exploit opportunities in non-ABS subframes when interference is acceptable while maintaining protection during ABS subframes.
Solution Approach 2:
The patent incorporates feedback mechanisms where the pico cell measures actual interference levels during ABS subframes and uses this feedback to optimize scheduling decisions. The measured interference information is fed back to the scheduler, which then adjusts resource allocation strategies to maximize utilization in non-ABS subframes while maintaining interference protection where needed, creating a closed-loop optimization system.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A resource management system and method for inter-cell interference coordination and channel information feedback in a mobile communication system are provided. The resource management method includes transmitting an Almost Blank Subframe (ABS) set from a first base station to a second base station, transmitting a reference resource configuration set for channel measurement and a Radio Link Monitor/Radio Resource Measurement (RLM/RRM) for radio resource measurement from the second base station to a terminal, and scheduling, at the second base station, the terminal in a subframe selected from the ABS set.