Adaptive Target PER Control for Wireless Capacity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, fixed target Packet Error Rates (PER) fail to adapt to channel variations, leading to suboptimal radio link reliability, capacity, and coverage, especially when Hybrid Automatic Repeat reQuest (HARQ) is used, resulting in inefficiencies and losses in system performance.
Innovation Solution
An apparatus and method for deciding an adaptive target PER that adjusts based on channel variations and HARQ considerations, using a target PER setter, comparator, and updater to calculate and update the target PER variance, thereby optimizing system capacity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a fixed target PER is used, then the system capacity can be maintained at a certain level, but the system cannot adapt to channel variations leading to suboptimal performance
Solution Approach 1:
The patent implements dynamic target PER adjustment by introducing a target PER variation parameter that adapts to channel conditions. The base station dynamically modifies the target PER based on feedback from mobile stations about their actual PER experiences and channel quality indicators, transforming the static fixed PER into a dynamic adaptive parameter that responds to varying channel conditions while maintaining system capacity.
Solution Approach 2:
The patent changes the target PER parameter from a fixed value to a variable that can be adjusted based on channel conditions. By introducing target PER variation and allowing it to change according to measured channel quality and actual PER feedback, the system optimizes performance across different channel states while maintaining overall system capacity.
2Reliability
If the target PER is set low to improve radio link reliability, then reliability increases but the reverse CINR required increases reducing system capacity
Solution Approach 1:
The patent introduces target PER variation that allows the target PER to be adjusted dynamically based on channel conditions. When channel conditions are good, the target PER can be relaxed (increased) to improve capacity. When channel conditions deteriorate, the target PER is tightened (decreased) to maintain reliability. This dynamic parameter adjustment resolves the trade-off between reliability and capacity.
Solution Approach 2:
The system transitions from a static target PER to a dynamic one that adapts to channel variations. The base station monitors channel quality and actual PER feedback, then dynamically adjusts the target PER to achieve the desired balance between reliability and capacity differentially across time and channel conditions.
3Productivity
If the target PER is set high to increase system capacity, then capacity increases but radio link reliability decreases
Solution Approach 1:
The patent enables the target PER to vary dynamically based on channel conditions. When channel quality is high, the target PER can be set higher to maximize capacity. When channel quality degrades, the target PER is reduced to maintain acceptable reliability levels. This conditional parameter adjustment allows the system to optimize for capacity when possible and for reliability when necessary.
Solution Approach 2:
The system implements dynamic target PER adjustment that responds to real-time channel conditions. The base station adapts the target PER upward when channels are favorable to boost capacity, and downward when channels deteriorate to preserve reliability, creating a dynamic balance between these competing objectives.
4Productivity
If HARQ is used to restore errors through retransmission, then the system can operate at higher target PER, but a fixed target PER causes loss of HARQ gain
Solution Approach 1:
The patent introduces target PER variation that allows the target PER to increase when HARQ is active and channel conditions permit. By dynamically adjusting the target PER upward based on HARQ retransmission success and channel quality, the system fully utilizes HARQ gain to operate at higher effective target PERs, thereby increasing reverse throughput while maintaining reliability through the combination of adaptive targeting and retransmission.
Solution Approach 2:
The system dynamically adjusts the target PER to exploit HARQ capabilities. When HARQ retransmissions are successful and channel conditions are favorable, the target PER is increased to maximize throughput. This dynamic adaptation ensures that HARQ gain is fully utilized rather than lost due to overly conservative fixed target PER settings.
Data Source
AI summary
An apparatus and method for deciding a target Packet Error Rate (PER) in a wireless communication system are provided. The method includes setting a target PER, comparing a variance of the target PER (Δp(k)) with a previous target PER variance (Δp(k−1)), and updating a next target PER variance (Δp(k+1)) using an average capacity and a previous average capacity in accordance with the comparison result between the target PER variance (Δp(k)) and the previous target PER variance (Δp(k−1)).