Automated PCID Allocation for Cellular Network Interference Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In cellular networks, the limited number of physical cell identifiers (PCIDs) leads to collisions and downlink reference signal time-frequency collisions, particularly when neighboring sectors use the same PCID, causing interference and requiring manual assignment, which is inefficient.
Innovation Solution
An automated system determines the reuse distance for available PCIDs and selects the one with the largest reuse distance and a different physical layer ID to minimize collisions, using an element management system to assign PCIDs, prioritizing unused PCIDs to conserve network resources and prevent interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If PCID reuse is implemented in cellular networks, then the limited number of PCIDs can be utilized more efficiently, but PCID collisions and downlink reference signal time-frequency collisions occur when neighboring sectors use the same PCID
Solution Approach 1:
The patent applies local quality by allowing different PCID allocation strategies in different spatial locations. Specifically, the system determines reuse distances based on geographic proximity and assigns PCIDs such that neighboring sectors avoid collisions while non-neighboring sectors can reuse PCIDs. This creates location-dependent PCID assignment where the same PCID can be used in different regions without causing interference
Solution Approach 2:
The patent introduces a spatial dimension to PCID allocation by calculating reuse distances between sectors. Instead of treating PCID assignment as a simple one-dimensional problem of assigning identifiers, the system adds geographic distance as another dimension, using spatial relationships to determine which PCIDs can be safely reused. This transforms the allocation problem from a flat assignment to a three-dimensional consideration incorporating geographic coordinates
2Reliability
If manual PCID assignment is used, then PCID collisions can be avoided through operator control, but the process becomes inefficient and time-consuming
Solution Approach 1:
The patent implements self-service by enabling the network system to automatically perform PCID allocation without requiring manual operator intervention. The system autonomously calculates reuse distances between sectors, identifies suitable PCIDs from the available pool, and assigns them according to the optimization criteria. This automated self-service mechanism eliminates the time-consuming manual assignment process while maintaining reliable collision avoidance
Solution Approach 2:
The patent employs feedback mechanisms where the system continuously monitors the network state, including existing PCID assignments and sector locations. Based on this feedback information, the system dynamically determines optimal PCID allocations. The reuse distance calculations and collision detection processes provide feedback loops that guide the automated assignment, ensuring reliable operation while reducing manual intervention time
3Device complexity
If neighboring sectors use the same physical layer ID, then downlink reference signal transmission can be simplified, but time-frequency collision occurs between reference signals of neighboring sectors
Solution Approach 1:
The patent applies local quality by making physical layer ID assignment location-dependent. Instead of using the same physical layer ID universally for simplicity, the system assigns different physical layer IDs to neighboring sectors based on their spatial relationships. This ensures that while non-neighboring sectors can use identical physical layer IDs (maintaining simplicity), neighboring sectors have differentiated IDs that prevent time-frequency collisions
Solution Approach 2:
The patent implements preliminary action by pre-calculating and assigning different physical layer IDs to neighboring sectors before downlink reference signal transmission begins. The system proactively identifies sectors that are geographically close and assigns them distinct physical layer IDs in advance, preventing potential time-frequency collisions before they occur rather than dealing with interference after transmission
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A computer-implemented method, a system, and a non-transitory storage media are disclose. The method includes receiving data identifying an unassigned sector to assign a physical cell identifier, PCID. The sector is associated with a base station in a communications network. Furthermore, receiving a list of PCIDs associated with a plurality of sectors different from the unassigned sector, determining a set of PCIDs available for assignment using the list of PCIDs associated with the plurality of sectors and a plurality of PCIDs associated with a plurality of sectors neighboring the unassigned sector, and assigning a PCID in the set of PCIDs available for assignment to the unassigned sector.