Base Station Power Control for D2D Discovery Signals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current specifications lack a mechanism for effectively controlling Device-to-Device (D2D) communication in mobile communication systems, leading to difficulties in establishing and maintaining D2D connections due to inappropriate transmission power settings of discovery signals, which can result in interference with cellular communication.
Innovation Solution
A base station transmits power control information to user terminals to designate appropriate transmission power for discovery signals, allowing adaptive power settings based on cell characteristics, user location, and propagation loss, enabling efficient D2D communication while minimizing interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If user terminals transmit discovery signals with high transmission power to ensure D2D connection establishment, then D2D communication reliability is improved, but interference with cellular communication increases
Solution Approach 1:
The patent applies parameter changes by dynamically adjusting the transmission power of discovery signals based on multiple factors including cell type (macrocell/picocell), user terminal location, propagation loss, and cell characteristics. The base station calculates appropriate power levels and communicates them to user terminals, ensuring sufficient power for D2D connection establishment while preventing excessive interference to cellular communication.
Solution Approach 2:
The patent implements feedback mechanisms where user terminals report their location information and propagation loss measurements to the base station. The base station uses this feedback to calculate and communicate optimal transmission power settings for discovery signals, creating a closed-loop control system that balances D2D reliability with cellular interference prevention.
2Device complexity
If user terminals use default transmission power settings for discovery signals, then device complexity is reduced, but D2D communication control accuracy deteriorates
Solution Approach 1:
The patent introduces the base station as an intermediary that performs the complex power control calculations and communications. Instead of requiring user terminals to independently determine optimal power settings (which would increase terminal complexity), the base station receives location and propagation information from terminals, calculates appropriate power levels, and communicates these settings back to the terminals, thereby maintaining low terminal complexity while achieving high control accuracy.
3Adaptability or versatility
If transmission power of discovery signals is increased to extend detection range, then D2D discovery capability is improved, but energy consumption increases
Solution Approach 1:
The patent applies parameter changes by dynamically adjusting transmission power based on actual propagation conditions and user location. Instead of using fixed high power settings that would guarantee maximum range but waste energy, the system calculates the minimum necessary power to achieve sufficient discovery range given current conditions, thereby extending effective discovery capability while minimizing energy consumption.
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
Abase station, which accommodates a user terminal that transmits a discovery-use signal used for discovering a communication partner terminal in D2D communication that is direct device-to-device radio communication in a mobile communication system that supports the D2D communication, comprises a control unit that controls transmission of power control information for designating transmission power of the discovery-use signal to the user terminal.