Multi-site Data Splitting for LTE Inter-cell Interference Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing LTE-based radio access systems face challenges in managing inter-cell interference and optimizing cell range coverage, particularly in heterogeneous networks, which affect data throughput and coverage.
Innovation Solution
The implementation of Almost Blank Subframes (ABS) and Low Power Subframes (LPS) with coordinated antenna beam tilting and timing advance mechanisms to adjust cell range coverage on a per-subframe basis, along with multi-site data flow splitting and time domain multiplexing to reduce interference and enhance data transmission efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If traditional LTE downlink transmission is used across entire bandwidth, then wide coverage is achieved, but inter-cell interference increases significantly
Solution Approach 1:
The patent segments the downlink transmission bandwidth into multiple contiguous sub-band portions and assigns different subsets of these portions to different wireless transmit/receive units. This segmentation allows multiple WTRUs to receive data simultaneously on different frequency resources without causing inter-cell interference, as each WTRU is allocated a unique subset of sub-band portions within the same cell coverage area.
Solution Approach 2:
The patent applies local quality by allowing different WTRUs to receive data on different sub-band portions tailored to their specific channel conditions and interference environments. Each WTRU is allocated a customized subset of sub-band portions that optimizes its local reception quality while minimizing contribution to overall inter-cell interference in the network.
2Object-generated harmful factors
If single-carrier FDMA is used for uplink, then interference is reduced, but frequency utilization efficiency decreases
Solution Approach 1:
The patent introduces dynamic resource allocation where WTRUs can switch between single-carrier and multi-carrier transmission modes based on channel conditions, traffic requirements, and interference levels. The eNodeB dynamically assigns different subsets of sub-band portions to different WTRUs, allowing the system to adaptively optimize between interference reduction and frequency utilization efficiency in real-time.
Solution Approach 2:
The patent transitions from traditional single-carrier uplink by introducing frequency dimension diversity through contiguous sub-band allocations. While maintaining the single-carrier waveform structure for interference reduction, the system utilizes multiple contiguous sub-band portions in the frequency dimension to achieve higher frequency utilization efficiency, effectively adding a frequency resource dimension while preserving the interference benefits of single-carrier transmission.
3Speed
If data is transmitted across the entire transmission bandwidth to a single WTRU, then high data rates are achieved, but vulnerability to frequency-selective fading increases
Solution Approach 1:
The patent segments the transmission bandwidth into multiple sub-band portions and allocates different subsets to different WTRUs. This segmentation ensures that no single WTRU is vulnerable to deep fades across the entire bandwidth, as each WTRU's data is confined to a narrower frequency range where frequency-selective fading has less impact. The system maintains high aggregate data rates by efficiently utilizing all sub-band portions across multiple WTRUs.
Solution Approach 2:
The patent changes the frequency allocation parameter by dynamically assigning different subsets of sub-band portions to different WTRUs based on channel conditions. When certain frequency bands experience fading, the system can reassign those sub-band portions to other WTRUs with better channel conditions, thereby adapting to changing fading patterns and maintaining both high data rates and reliability.
Data Source
AI summary
Methods and apparatus for changing cell range coverage are disclosed. A wireless transmit/receive unit (WTRU) may include circuitry configured to transmit subframes of radio frames using a physical uplink shared channel (PUSCH), where the subframes are divided into first and second sets. The circuitry may include a first power control loop utilized for the first set of subframes and a second power control loop utilized for the second set of subframes. The first power control loop may set transmission power levels for transmission over the PUSCH for the first set of subframes, and the second power control loop may set transmission power levels for transmission over the PUSCH for the second set of subframes. The circuitry may be configured with a first physical uplink control channel (PUCCH) for a first eNodeB and a second PUCCH for a second eNodeB to simultaneously communicate with the first and the second eNodeBs.