Sounding Reference Signal Power Control in TDD Wireless Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems, particularly in LTE, face challenges in efficiently controlling the transmission power of sounding reference signals, especially in time division duplex systems, due to varying interference environments and flexible resource usage changes, which affect uplink transmission performance.
Innovation Solution
The method involves establishing multiple power control processes for sounding reference signals and PUSCH (Physical Uplink Shared Channel) power control, allowing for independent power control settings for different subframe sets, such as static and flexible subframes, to optimize transmission power based on specific interference conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single power control process is used for SRS transmission across all subframes, then the system structure remains simple, but transmission performance deteriorates in flexible subframes with different interference environments
Solution Approach 1:
The patent divides the power control mechanism into multiple independent processes: a first power control process for static subframes and a second power control process for flexible subframes. Each process maintains independent parameters (P0, alpha, pathloss compensation) allowing optimized power control for different subframe types without requiring complete restructuring of the power control system.
Solution Approach 2:
The patent introduces dynamic power control adaptation by selecting different power control processes based on subframe type. The second power control process dynamically adjusts SRS transmission power in flexible subframes according to specific interference conditions, while the first process maintains stable power control in static subframes, creating a dynamic rather than static power control system.
2Reliability
If independent power control processes are established for different subframe sets, then SRS transmission stability improves in flexible subframes, but system complexity increases
Solution Approach 1:
The patent applies different power control parameters and processes to different subframe locations: static subframes use the first power control process with parameters optimized for stable interference environments, while flexible subframes use the second power control process with parameters adapted for varying interference conditions. This local differentiation improves overall system reliability without requiring complete system redesign.
Solution Approach 2:
The patent creates a multi-functional power control system where the base power control structure serves both static and flexible subframes through configurable processes. The second power control process can be selectively applied to flexible subframes while maintaining compatibility with the overall LTE TDD framework, allowing the system to handle multiple subframe types with a unified yet adaptable architecture.
3Productivity
If power control parameters are adjusted frequently to adapt to interference changes, then transmission efficiency improves, but power control overhead increases
Solution Approach 1:
The patent implements periodic power control updates specific to flexible subframes through the second power control process. Rather than continuous adjustment in all subframes, the system applies targeted periodic power control only where needed (in flexible subframes with varying interference), reducing overall signaling overhead while maintaining transmission efficiency in critical periods.
Data Source
Figure 1
Figure 2(a)~2(b)
Figure 3
AI summary
Disclosed in the present application is a method for transmitting a sounding reference signal (SRS) from a terminal to a base station in a time division duplex (TDD) system. More specifically, the method comprises: a step of establishing a first subframe set and a second subframe set through an upper layer, and step of transmitting the sounding reference signal from a specific subframe to the base station, wherein the first subframe set and the second subframe set are configured by an uplink subframe and/or a special subframe, each of the first subframe and the second subframe is associated with a power control process for transmitting an uplink data channel, and wherein the transmission power of the sounding reference signal is determined on the basis of a specific power control process associated with a subframe set to which the specific subframe belongs, from among the first subframe set and the second subframe set.