Mobile OWC Receiver with Maximum Ratio Coupling
Solution Overview
Problem
Conventional wireless optical communication systems face challenges with solar noise interference and frequent link losses due to mobility and obstacles, which can cause reception sensitivity degradation and communication paralysis, especially in mobile OWC systems.
Innovation Solution
A mobile wireless optical communication receiver system with a photoelectric amplification receiver structure that includes an optical amplifier, diplexer, attenuator, and photodetectors to filter and process optical signals and solar noise, using maximum ratio combining algorithms for adaptive diversity gain.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If solar noise filtering is implemented using conventional methods, then solar noise interference is reduced, but reception sensitivity deteriorates due to loss of useful optical signal
Solution Approach 1:
The optical signal is segmented into multiple wavelength components using a diplexer, separating the in-band signal from out-of-band solar noise. This allows selective processing of different spectral components to mitigate noise while preserving signal integrity.
Solution Approach 2:
The system dynamically adjusts the attenuation parameter based on detected solar noise levels. When solar noise is detected in the out-of-band region, the attenuation applied to the in-band signal is optimized to maintain reception sensitivity while blocking noise.
2Measurement precision
If optical amplification is increased to improve signal strength, then reception sensitivity is improved, but receiver damage occurs due to excessive solar noise power
Solution Approach 1:
The harmful out-of-band solar noise component is extracted and removed from the optical signal using an optical diplexer before amplification. This prevents excessive noise power from damaging the receiver while allowing useful in-band signal amplification.
Solution Approach 2:
Solar noise detection and attenuation are performed preliminarily before optical amplification. The system detects solar noise in the out-of-band region and applies appropriate attenuation to the in-band signal prior to amplification, preventing receiver damage while maintaining sensitivity.
3Reliability
If diversity combining is used to combat link losses, then communication reliability is improved, but system complexity increases due to multiple processing paths
Solution Approach 1:
Multiple diversity paths are merged into a single combined signal using maximum ratio combining. The system processes multiple received signals through unified attenuation and amplification stages, reducing complexity while maintaining reliability benefits.
Solution Approach 2:
The optical amplifier and detector are designed to handle both signal amplification and solar noise attenuation functions simultaneously. The same hardware components perform multiple functions across different wavelength bands, reducing overall system complexity.
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
The system effectively mitigates solar noise interference and maintains reception sensitivity by adaptively combining diversity gains, preventing receiver damage and ensuring reliable communication.
Implementation Method 1
an optical amplifier that amplifies the optical signal to output an amplified optical signal
Implementation Method 2
an optical diplexer for filtering and outputting the amplified optical signal into an in-band wavelength band and an out-of-band wavelength band
Implementation Method 3
a first photodetector for converting the attenuated target signal into a first baseband electrical signal
Implementation Method 4
a second photodetector for converting the solar noise present in the out-of-band wavelength band into a second baseband electrical signal
Data Source
AI summary
Provided are a method and a device used in an optical wireless communication (OWC) system. A receiver comprises an optical amplifier and detector that receives an optical signal including a target signal and/or daylight noise as an input to output baseband electrical signals for digital signal processing. The optical amplifier and detector comprises: (1) an optical amplifier that amplifies the optical signal; (2) an optical diplexer that filters the amplified optical signal into an in-band wavelength band and an out-of-band wavelength band, respectively; (3) an optical attenuator that receives the target signal present in the in-band wavelength band as an input and outputs an attenuated target signal; (4) a first photodetector that converts the attenuated target signal into a first baseband electrical signal; (5) an electric filter; and (6) a second photodetector that converts the daylight noise into a second baseband electrical signal.