D2D Ranging Subframe Timing for Wireless Interference Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems face challenges in performing ranging operations efficiently without causing interference, especially in Device-to-Device (D2D) communication scenarios where traditional methods may lead to increased interference and inefficiency.
Innovation Solution
A method involving a user equipment (UE) transmitting a D2D signal in a subframe N and receiving it in subframe N+K, where the timing is configured as a subframe boundary, allowing the UE to measure Round Trip Time (RTT) by detecting the signal reception timing, thereby minimizing interference and optimizing ranging operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional ranging methods are used in D2D communication, then ranging operation can be performed, but interference from cellular or D2D signals increases
Solution Approach 1:
The patent segments the communication resources by allocating specific subframes (N and N+K) dedicated to D2D ranging operations, separating them from cellular communication subframes. This segmentation reduces interference by ensuring that D2D ranging signals and cellular signals do not overlap in time resources.
Solution Approach 2:
The patent applies preliminary action by pre-configuring the timing relationship between subframe N (D2D signal transmission) and subframe N+K (D2D signal reception) before ranging operations begin. The network pre-allocates these subframes and informs UEs of the timing configuration, allowing UEs to perform ranging operations without dynamic negotiation, thus avoiding interference with ongoing cellular communications.
2Productivity
If D2D signal transmission and reception timing is not synchronized to subframe boundaries, then flexible timing can be achieved, but measurement precision of RTT deteriorates
Solution Approach 1:
The patent applies equipotentiality by aligning D2D signal transmission and reception timings to the common subframe boundary reference. All UEs synchronize their ranging operations to the same subframe grid, creating a uniform timing reference across the network. This eliminates timing offsets between different UEs and ensures consistent RTT measurement precision while maintaining adequate flexibility through the configurable subframe offset K.
3Productivity
If subframe N and subframe N+K are not configured as dedicated D2D subframes, then resource utilization is improved, but interference from other signals increases
Solution Approach 1:
The patent implements periodic action by configuring D2D ranging operations to occur in periodic subframes N and N+K that are specifically allocated for D2D communication. These subframes repeat at regular intervals according to the configured period, providing dedicated resources for D2D ranging while allowing cellular resources to be used for cellular traffic in non-D2D subframes, thus achieving both interference reduction and resource utilization.
Data Source
AI summary
One embodiment of the present invention relates to a method by which a user equipment (UE) performs ranging in a wireless communication system, comprising the steps of: transmitting a D2D signal in a subframe N by a first UE; receiving the D2D signal in a subframe N+K from a second UE, which has set, as a subframe boundary, a time point at which the D2D signal is received; and measuring, by the first UE, a round trip time (RTT) by detecting a reception time point of the D2D signal transmitted by the second UE.