Dynamic Subcarrier Allocation for PAPR Reduction
Solution Overview
Problem
Conventional spectrum control single carrier communication systems face inefficiencies in subcarrier allocation, leading to degraded communication efficiency and peak-to-average power ratio (PAPR) characteristics, especially in environments with high frequency selectivity and interference.
Innovation Solution
A base station and mobile terminal device system that dynamically groups and arranges subcarriers into separate or continuous groups, allowing for adaptive selection of modulation schemes and frequency domain signal allocation based on channel conditions to optimize communication quality and PAPR.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If subcarriers are allocated using conventional L allocation or D allocation, then the system structure is simple and easy to implement, but communication efficiency is degraded and PAPR characteristics are poor in high frequency selectivity environments
Solution Approach 1:
The patent segments the frequency spectrum into multiple blocks and further divides subcarriers within each block into groups. This segmentation allows the system to select and allocate subcarriers in a more flexible and optimized manner, improving communication efficiency while maintaining manageable system complexity through structured organization.
Solution Approach 2:
The patent introduces dynamic subcarrier allocation where the base station adaptively selects and allocates subcarriers based on channel conditions, user requirements, and system state. This dynamic approach replaces static allocation schemes, enabling the system to optimize communication efficiency and PAPR characteristics according to real-time conditions while maintaining implementation feasibility through algorithmic control.
2Device complexity
If subcarriers are allocated using conventional L allocation or D allocation, then the allocation rule is simple, but PAPR characteristics are degraded
Solution Approach 1:
The patent applies local quality optimization by treating different blocks of frequency spectrum with different allocation strategies. Each block can have its subcarriers allocated independently based on local channel conditions, allowing the system to optimize PAPR characteristics in each local region while maintaining overall system manageability through modular block structure.
Solution Approach 2:
The patent implements dynamic subcarrier allocation that adapts to changing channel conditions and system state. The base station continuously monitors and adjusts subcarrier allocation to maintain optimal PAPR characteristics, replacing static allocation rules with adaptive control that responds to real-time conditions while maintaining implementation feasibility.
3Reliability
If the number of frequency domain signals included in each segment is increased, then PAPR characteristics are improved, but communication efficiency is degraded due to insufficient subcarrier selection freedom
Solution Approach 1:
The patent divides the frequency spectrum into multiple blocks and further segments subcarriers within each block into groups. This multi-level segmentation provides the freedom to select optimal numbers of frequency domain signals for each segment independently, allowing the system to optimize PAPR characteristics in each segment while maintaining overall communication efficiency through diverse subcarrier selection across blocks.
Solution Approach 2:
The patent enables dynamic adjustment of the number of frequency domain signals included in each segment as a controllable parameter. The base station can optimize this parameter for each segment based on channel conditions and system requirements, allowing flexible trade-off between PAPR characteristics and communication efficiency by changing this key parameter adaptively.
4Productivity
If subcarriers are allocated to maximize communication efficiency, then throughput is improved, but PAPR characteristics are degraded due to non-optimal subcarrier combinations
Solution Approach 1:
The patent optimizes subcarrier allocation locally within each block and segment rather than globally across the entire spectrum. This local optimization allows the system to select subcarrier combinations that simultaneously maximize communication efficiency and maintain good PAPR characteristics by considering local channel conditions and interference patterns specific to each region.
Solution Approach 2:
The patent implements dynamic optimization that simultaneously considers both communication efficiency and PAPR characteristics when allocating subcarriers. The base station uses adaptive algorithms to select subcarrier combinations that balance throughput maximization with PAPR control, replacing single-objective optimization with multi-objective dynamic optimization that responds to real-time system state.
Data Source
AI summary
A wireless transmission device converts signals having been subjected to a first modulation into frequency domain signals, and allocates the frequency domain signals converted to subcarriers for transmission. The wireless transmission device includes: a controller that selects, based on channel qualities of the subcarriers to which the frequency domain signals are allocated, a value satisfying a predetermined communication quality as control information indicative of the number of frequency domain signals included in each of segments into which the frequency domain signals are segmentalized; and an allocating unit that segmentalizes the frequency domain signals into segments, each of the segments including the same number of frequency domain signals as the value selected as the control information by the controller, and allocates the frequency domain signals included in each of the segments to sequential subcarriers.