Small Cell Base Station Dummy Handover Pilot Signal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In cellular network environments with numerous small cells, especially in large buildings, the limited capacity of neighbor lists in macro cell base stations hinders optimal handover processes for user terminals moving between macro cells and small cells.
Innovation Solution
Implementing a dummy handover cell mechanism where small cell base stations transmit a common pilot signal (P-CPICH) with adjustable power and timing, allowing macro cell user terminals to seamlessly transition to small cells, and utilizing additional control channels like P-CCPCH and SCH to ensure interoperability and minimize interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If multiple small cell base stations are deployed in large buildings to increase network capacity and coverage, then network capacity and coverage are improved, but handover complexity and difficulty increase due to limited neighbor list capacity in macro cell base stations
Solution Approach 1:
Multiple small cell base stations transmit a common pilot signal (P-CPICH) that is identical across all small cells. This merging of pilot signals creates a unified signal environment that allows user terminals to detect and handover to small cells without requiring the macro cell base station to maintain extensive neighbor lists for each individual small cell, thereby reducing handover complexity while preserving network capacity
Solution Approach 2:
The common pilot signal serves multiple functions simultaneously: it enables user terminals to detect small cells for handover purposes, provides timing synchronization, and allows power control adjustments to manage interference. This multi-functionality reduces the need for separate mechanisms, simplifying the overall handover process in dense small cell deployments
2Measurement precision
If small cell base stations transmit common pilot signals with high power to improve detection probability, then user terminal detection capability is improved, but interference to other cells increases
Solution Approach 1:
The pilot signal transmission power of small cell base stations is made adjustable and controllable rather than fixed. The network can dynamically adjust the power levels based on traffic conditions, user density, and interference measurements, allowing optimization of detection probability while minimizing interference to other cells and macro cells
Solution Approach 2:
By changing the power parameter of the common pilot signal transmitted by small cell base stations, the system can optimize the balance between detection capability and interference. The adjustable power level allows the pilot signal to be strong enough for reliable detection by user terminals while remaining weak enough to minimize harmful interference to other cells
Data Source
Figure 1~2
Figure 3~4A
Figure 4B~5
AI summary
An apparatus and a method for controlling transmissions of base stations are proposed. In the method, the apparatus belongs (200) to a set of apparatuses controlled by a common controller, transmits (202) at least one control signal unique to the apparatus within a given area and transmits (204) also a second control signal common to a set of apparatuses controlled by the same controller.