Transport Network Synchronization for Split Base Stations
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless network technologies face challenges in synchronizing base stations across different types, especially with the increasing demand for frequency and time/phase accuracy, particularly in 4G networks with higher frequency bands, which affect coverage and capacity, especially with the use of split remote radio units and centralized baseband processing units.
Innovation Solution
A method is introduced where a transport network connects a first wireless base station with a remote radio unit and a remotely located baseband processing unit, allowing for the transmission of synchronous time division multiplexed communication signals to synchronize frequency and phase across base stations, using existing TDM signals like CPRI, and Precision Time Protocol (PTP) messages to maintain accurate clock synchronization without the need for separate synchronization schemes for each base station.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If separate synchronization schemes are implemented for each base station type, then synchronization accuracy is improved, but device complexity and equipment requirements increase
Solution Approach 1:
The patent implements a universal synchronization scheme where the transport network extracts frequency synchronization signals from TDM communication signals and distributes them to all base station types (monolithic and split-architecture) through a common interface. This multi-functional approach allows the same synchronization mechanism to serve different base station configurations, achieving synchronization accuracy without requiring separate specialized equipment for each base station type.
Solution Approach 2:
The synchronization system utilizes the existing TDM communication signals already present in the transport network to carry frequency synchronization information. Rather than requiring separate dedicated synchronization channels or equipment, the system self-services by embedding synchronization data within the operational communication traffic, thereby reducing additional equipment requirements while maintaining synchronization accuracy.
2Measurement precision
If separate synchronization schemes are implemented for each base station type, then synchronization accuracy is improved, but signaling overhead in the transport network increases
Solution Approach 1:
The patent merges the frequency synchronization function with the existing TDM communication signals by embedding synchronization information within the same transport infrastructure. Instead of implementing separate dedicated synchronization channels that would increase signaling overhead, the system combines synchronization data with operational communication traffic, achieving synchronization accuracy without proportionally increasing the quantity of signaling in the network.
3Measurement precision
If additional synchronization infrastructure is deployed, then frequency and phase synchronization accuracy is improved, but network cost and complexity increase
Solution Approach 1:
The system achieves frequency and phase synchronization by utilizing existing TDM communication signals and standard transport network infrastructure. Rather than deploying additional dedicated synchronization equipment or infrastructure, the system extracts and utilizes synchronization information from the operational communication traffic itself, thereby achieving high synchronization accuracy without the cost and complexity of additional infrastructure.
4Device complexity
If monolithic base stations are used, then device complexity is reduced, but adaptability to different network architectures decreases
Solution Approach 1:
The patent implements a universal synchronization interface that works with both monolithic base stations and split-architecture base stations with remote radio units. The transport network extracts frequency synchronization signals from TDM signals and distributes them through a common mechanism that adapts to different base station configurations, allowing monolithic base stations to maintain simplicity while the overall system remains adaptable to various network architectures including distributed and virtualized deployments.
Data Source
Figure 1
Figure 2A~2B
Figure 3A~3B
AI summary
A transport network (20) is connected to a first wireless base station (3, 4) and to a second wireless base station (6). The first wireless base station comprises a remote radio unit (3) and a baseband processing unit (4) which are connected by the transport network (20). A node (16) of the transport network (20) receives a synchronous time division multiplexed communication signal which carries at least a first communication signal between the baseband processing unit (4) and the remote radio unit (3). The node (16) determines a frequency synchronisation signal from the synchronous time division multiplexed communication signal. The node (16) transmits the synchronous time division multiplexed communication signal to the remote radio unit (3) of the first wireless base station. The node (16) transmits the frequency synchronisation signal to the second wireless base station (6). The node (16) also assists with providing phase/time synchronisation to the second wireless base station (6).