Fractional Power Control for D2D Interference Mitigation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, device-to-device (D2D) communications can interfere with macro evolved NodeB (eNB) operations, and existing methods lack an effective mechanism to manage resource allocation and power control to mitigate this interference, especially when UEs in neighboring cells engage in D2D communications.
Innovation Solution
The system generates a fractional power control parameter based on the macro eNB power saturation value and broadcasts it to UEs engaged in D2D communications, allowing them to adjust their transmit power levels to minimize interference by comparing the fractional power control parameter plus path loss to the maximum power used for D2D communications.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If UEs engage in D2D communications using allocated resources, then direct communication between devices is enabled, but interference to macro eNB operations occurs
Solution Approach 1:
The patent implements power control by dynamically adjusting the transmit power parameter of UEs engaged in D2D communications. The eNB calculates a maximum transmit power level based on uplink channel conditions and communicates this to the UEs, which then modify their transmission power accordingly. This parameter change resolves the contradiction by enabling D2D communication while controlling the interference level to the macro eNB.
2Reliability
If UE transmit power is increased for D2D communications, then communication reliability between devices improves, but interference to macro eNB physical uplink control channel increases
Solution Approach 1:
The patent establishes a feedback mechanism where the eNB monitors uplink channel conditions and communicates maximum power levels to UEs engaged in D2D communications. The eNB sends power control commands based on observed interference levels and channel quality, creating a closed-loop system that adjusts D2D transmit power in real-time to maintain reliability while protecting PUCCH from excessive interference.
3Object-affected harmful factors
If fractional power control parameter is implemented, then interference to macro eNB is reduced, but complexity of power management increases
Solution Approach 1:
The patent introduces the eNB as an intermediary that centralizes the complex power control calculations. Instead of requiring UEs to independently calculate and coordinate power levels (which would be complex), the eNB receives channel condition information, computes the fractional power control parameter, and communicates the maximum power level to UEs. This mediator approach reduces interference while managing complexity centrally rather than distributing it across multiple devices.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method, an apparatus, and a computer program product for wireless communication are provided for using power control to reduce potential interference to a macro eNB by a UE engaged in D2D communications. An eNB may be operable to generate a fractional power control parameter based on a macro eNB power saturation value and broadcast the factional power control parameter. A UE may be equipped to receive the factional power control parameter and determine whether the fractional power control parameter plus a path loss value between the UE and the macro eNB is less than a maximum power used for the D2D communications. The UE may reduce the maximum transmit power used for D2D communications when the fractional power control parameter plus a path loss value between the UE and the macro eNB is less than a maximum power used for the D2D communications.