Femto Base Station Interference Control via Sounding Signal Coordination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In hierarchical cell communication systems, interference from femtocells to macrocells is a challenge due to difficulties in sharing channel information in real-time, especially since femtocells are connected to macrocells via the Internet, leading to delays and inefficiencies in interference control.
Innovation Solution
A method involving a macro base station controlling transmission power and using a sounding signal to facilitate real-time channel information sharing between femto and macro base stations, employing long-term dynamic spectrum management and leakage-based beamforming to minimize interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If real-time channel information sharing is implemented between femto and macro base stations, then interference control effectiveness is improved, but system complexity and implementation difficulty increase due to the need for direct connections and real-time data exchange
Solution Approach 1:
The patent introduces a spectrum manager as an intermediary component that mediates between femto and macro base stations. This spectrum manager collects channel information from both sides, performs calculations, and generates control signals, thereby enabling interference control without requiring direct real-time connections between the base stations. This resolves the contradiction by maintaining reliability through effective interference control while reducing system complexity through the use of an intermediary mediator.
Solution Approach 2:
The patent implements a feedback mechanism where the spectrum manager receives channel information from femto and macro base stations, processes this information, and sends control signals back to adjust transmission powers. This closed-loop feedback system enables effective interference control based on actual channel conditions while avoiding the need for complex direct real-time sharing protocols between base stations.
2Speed
If direct connection between femto and macro base stations is established for real-time communication, then information sharing speed is improved, but network architecture complexity and cost increase
Solution Approach 1:
The spectrum manager serves as an intermediary that enables information sharing between femto and macro base stations without requiring direct connections. The spectrum manager receives information from both base stations via existing network connections, processes the data, and generates appropriate control signals. This approach maintains information sharing effectiveness while avoiding the architectural complexity of direct base station connections.
3Area of stationary object
If transmission power is increased to improve signal coverage, then coverage area is improved, but interference to macro terminals increases
Solution Approach 1:
The patent dynamically adjusts transmission power parameters based on real-time channel information and interference conditions. The spectrum manager modifies transmission power levels of both femto and macro base stations according to calculated interference levels, allowing the system to optimize coverage while minimizing harmful interference to macro terminals through parameter adaptation.
Solution Approach 2:
The system implements feedback control where channel information from macro terminals is continuously monitored and fed back to the spectrum manager. Based on this feedback, the transmission power of femto base stations is adjusted to maintain adequate coverage while preventing excessive interference to macro terminals, creating a balanced power control mechanism.
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
System and methods for intercell coordination are provided. The system includes a macro terminal and a macro base station that allocate a radio resource for a sounding signal and determine a pattern of a sounding signal, in advance. The macro base station provides a femto base station included in the system with information about the pattern of the sounding signal, and the information about the radio resource of the sounding signal. The femto base station may receive the sounding signal from the macro terminal based on the information, and thus, the femto base station may determine whether the macro terminal exists and may determine a channel between the macro terminal and the femto base station.