Base Station Optical Clock Distribution for RF Synchronization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In high-speed land mobile environments, accurate radio frequency synchronization among multiple ground antennas in a linear cell is crucial to prevent performance degradation due to interference and frequent handovers, which is challenging in remote radio systems where each antenna independently performs frequency conversion.
Innovation Solution
A base station apparatus with a ground station device that performs electrical-optical conversion and wavelength division multiplexing of signals, and ground antenna devices that demultiplex and up-convert signals using a shared reference clock signal to ensure accurate frequency synchronization across antennas.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If each ground antenna independently performs frequency conversion, then device complexity is reduced and ease of manufacture is improved, but radio frequency synchronization accuracy deteriorates
Solution Approach 1:
The patent introduces an optical signal as an intermediary carrier to transmit the reference clock signal from the ground station to multiple ground antennas. This optical intermediary enables precise frequency synchronization across distributed antennas while maintaining the simplicity of independent frequency conversion at each antenna, thus resolving the contradiction between ease of manufacture and synchronization accuracy.
2Device complexity
If radio frequency synchronization is not accurate, then device complexity is reduced, but performance degradation occurs due to interference and frequent handovers
Solution Approach 1:
The optical signal serves as a mediator to distribute the reference clock signal accurately to all ground antennas, enabling precise frequency synchronization. This resolves the contradiction by maintaining low device complexity while ensuring high communication reliability through accurate synchronization, preventing interference and handover issues.
3Device complexity
If signals with radio frequency errors are transmitted from distant ground antennas, then device complexity is reduced, but signal interference occurs between nearby and distant antenna signals
Solution Approach 1:
The optical reference clock signal acts as an intermediary that ensures all ground antennas operate at precisely synchronized frequencies. This eliminates radio frequency errors in transmitted signals, preventing interference between signals from nearby and distant antennas while maintaining the simplicity of the frequency conversion architecture.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enables precise synchronization of wireless signals from multiple ground antennas, reducing interference and handover issues, thereby enhancing communication performance and efficiency.
Implementation Method 1
The ground station device performs electrical-optical conversion on an analog electrical signal to be transmitted to a mobile station and a reference clock signal
Implementation Method 2
performs optical-electrical conversion on the demultiplexed optical signals to generate electrical signals
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A base station apparatus (1) includes a ground station device (100) and a plurality of ground antenna devices (200-1 to 200-N) coupled to the ground station device via an optical transmission path. The ground station device performs electrical-optical conversion on an analog electrical signal to be transmitted to a mobile station and a reference clock signal to generate optical signals, performs wavelength division multiplexing on the obtained optical signals to generate a multiplexed optical signal, and outputs the multiplexed optical signal to the optical transmission path. Each of the plurality of ground antenna devices demultiplexes the multiplexed optical signal input from the optical transmission path into demultiplexed optical signals, performs optical-electrical conversion on the demultiplexed optical signals to generate electrical signals, up-converts a frequency of the analog electrical signal obtained through the optical-electrical conversion based on the reference clock signal obtained through the optical-electrical conversion to generate an up-converted signal, and transmits the up-converted signal to the mobile station.