UE Cooperation Using Partial LLR Relaying for Bandwidth Savings
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Solution Overview
Problem
Existing user equipment (UE) cooperation methods in wireless communications require extensive bandwidth for forwarding log-likelihood ratios (LLRs), which is inefficient, especially when not all LLRs are equally useful for decoding signals.
Innovation Solution
The method involves selecting and forwarding only the most useful LLRs from cooperating UEs to a target UE, using techniques like LLR combining, where cooperating UEs determine and transmit LLRs based on signal-to-noise ratios (SNRs) and resource block thresholds, and quantizing LLRs to reduce bandwidth usage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If all LLRs are forwarded from cooperating UEs to target UE, then decoding performance is improved, but bandwidth consumption increases significantly
Solution Approach 1:
The patent extracts and forwards only the most useful LLRs from cooperating UEs to the target UE, rather than forwarding all LLRs. This is achieved by selecting LLRs based on criteria such as signal quality metrics and redundancy analysis, thereby reducing bandwidth consumption while maintaining decoding performance.
Solution Approach 2:
The patent applies partial action by forwarding only a subset of LLRs that are deemed most beneficial for decoding. This selective forwarding approach avoids the excessive bandwidth consumption of transmitting all LLRs while still achieving sufficient decoding performance through the most valuable LLR components.
2Productivity
If selective LLR forwarding is implemented, then bandwidth efficiency is improved, but system complexity increases due to selection criteria
Solution Approach 1:
The patent changes parameters such as signal quality thresholds and redundancy metrics to establish practical selection criteria for LLR forwarding. By adjusting these parameters, the system achieves bandwidth efficiency through selective forwarding while keeping the selection process manageable through defined parameter-based rules.
3Quantity of substance
If quantization of LLRs is applied, then bandwidth usage is reduced, but precision of LLR values decreases
Solution Approach 1:
The patent applies quantization to LLR values with carefully selected precision levels that balance bandwidth reduction against precision maintenance. By optimizing the quantization parameters, the system achieves significant bandwidth savings while preserving sufficient LLR precision for effective decoding performance.
Data Source
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AI summary
User equipment (UE) cooperation can be improved by relaying partial soft information to target UEs. More specifically, a cooperating UE may relay a subset of log-likelihood ratios (LLRs) to the target UE. The subset of LLRs may correspond to fewer than all resource blocks of the original transmission. This may allow UE cooperation to be effective when the cooperating UE was only able to decode a portion of the original transmission. This may also allow fewer network resources (e. g., bandwidth, etc. ) to be used when the target UE does not need all of the soft information to decode the original transmission. Multiple cooperating UEs can provide different subsets of LLRs, and the subsets may or may not overlap with one another.