Optical Beamforming Signal Power Balancing in Fiber-Linked Base Stations
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wireless communication systems using millimeter-wave bands face challenges with high propagation loss and signal distortion due to non-linear optical effects in optical fibers, limiting the transmission of multiple signals with limited power.
Innovation Solution
A wireless communication method and system that adjusts power levels of beam control and transmission signals to prevent non-linear optical effects, using phase shifters and switches to perform beamforming in specific directions, allowing multiple signals to be transmitted without distortion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of stationary object
If high optical power is input into the optical fiber to enable long-distance transmission, then transmission distance is improved, but signal distortion occurs due to non-linear optical effects
Solution Approach 1:
The patent adjusts the power level of the beam control signal relative to the transmission signal by changing operational parameters. Specifically, it sets the beam control signal power to be lower than the transmission signal power, thereby operating within the linear region of the optical fiber's transfer characteristics and avoiding non-linear distortion while maintaining effective beamforming control
2Adaptability or versatility
If the number of wavelengths is increased to support more antenna elements for beamforming, then beamforming capability is improved, but signal distortion due to non-linear optical effects occurs more readily
Solution Approach 1:
The patent changes the power distribution parameter among multiple wavelengths by setting different power levels for control signals and transmission signals. This allows the system to support multiple wavelengths for enhanced beamforming capability while maintaining each signal within acceptable power levels that avoid non-linear optical effects
3Reliability
If transmission power is reduced to avoid non-linear optical effects, then signal quality is maintained, but the coverage area and transmission capability are limited
Solution Approach 1:
The patent applies different power levels to different signals within the same optical fiber system. The transmission signal uses higher power to extend coverage area, while the beam control signal uses lower power to avoid non-linear distortion. This localized quality differentiation allows both objectives to be achieved simultaneously
Solution Approach 2:
The patent segments the optical signal into distinct components (beam control signal and transmission signal) with different power requirements. By separating and independently managing the power levels of these signal components, the system achieves both high coverage area and high signal quality
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
Enables effective beamforming control while reducing signal distortion and maintaining wavelength efficiency, thereby simplifying and reducing the cost of extension stations.
Implementation Method 1
a signal is distorted due to a non-linear optical effect such as self-phase modulation or cross-phase modulation
Data Source
AI summary
A wireless communication method in a wireless communication system including an aggregation station and an extension station that is connected to the aggregation station by an optical fiber and performs beamforming according to control of the aggregation station, in which the aggregation station adjusts a power level of a beam control signal for controlling beamforming in the extension station and a power level of a transmission signal that is data to be transmitted in order to make an optical signal including at least the beam control signal and the transmission signal an optical signal in which distortion due to a non-linear optical effect does not occur in an optical fiber and transmits the beam control signal and the transmission signal to the extension station, and the extension station transmits the transmission signal by setting, in a phase shifter or by switching a switch, a phase difference for performing beamforming in a specific direction on a basis of the beam control signal included in the optical signal.