Multi-Carrier Self-Jamming Reduction via CCA
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Solution Overview
Problem
Wireless communication networks face interference issues due to asymmetric interference between adjacent carriers in multi-carrier transmissions, leading to degraded performance and congestion in busy networks.
Innovation Solution
Implementing extended clear channel assessment (ECCA) countdowns on primary unlicensed carriers and simple CCA on secondary carriers, or using large bandwidth load-based equipment (LBE) carriers with additional CCA timeslots to synchronize and reduce self-jamming between adjacent channels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multi-carrier transmissions are performed over adjacent channels, then network capacity and throughput are improved, but self-jamming and asymmetric interference occur between carriers
Solution Approach 1:
The system performs Clear Channel Assessment (CCA) checks before transmitting on each carrier to detect potential interference. By checking the channel status in advance and adjusting transmission parameters proactively, the system prevents self-jamming from occurring rather than reacting after it happens. This preliminary detection and adjustment mechanism allows multiple carriers to operate simultaneously without causing mutual interference.
Solution Approach 2:
The patent applies different transmission parameters and power levels to different carriers based on their specific interference conditions. Each carrier is configured with localized quality adjustments, such as modifying CCA thresholds, transmission power, or timing parameters individually, rather than applying uniform settings across all carriers. This allows optimal performance for each carrier while minimizing its impact on adjacent carriers.
2Object-generated harmful factors
If CCA checks are performed on all carriers before transmission, then self-jamming is reduced, but transmission delay increases
Solution Approach 1:
Instead of performing full CCA checks on all carriers before every transmission, the system performs CCA checks selectively based on interference conditions. When interference is detected on certain carriers, CCA checks are performed; when conditions are clear, transmissions proceed without extensive checking. This partial action approach reduces the overall time loss while still preventing self-jamming when necessary.
Solution Approach 2:
The system performs CCA checks at periodic intervals rather than continuously before every transmission. By establishing regular assessment cycles and using historical channel state information, the system reduces the frequency of full CCA procedures while maintaining adequate interference detection. This periodic approach balances thoroughness with transmission efficiency.
Data Source
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AI summary
The present disclosure provides methods and apparatuses for multi-carrier transmissions over adjacent channels that reduce self-jamming due to asymmetric interference. In an aspect, a large bandwidth load-base equipment (LBE) carrier may be provided such that CCA is performed jointly over the entire bandwidth. In another aspect, additional CCA timeslots may be used to synchronize the two carriers. In a further aspect, an extended CCA may be performed on a primary unlicensed carrier while a simple CCA may be performed on a secondary unlicensed carrier. In yet another aspect, LBE may be deployed on some carriers while frame-base equipment (FBE) may be deployed on other carriers.