Antenna Polarization Signaling for LOS MIMO Reception
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional MIMO systems experience reception quality degradation in Line-Of-Sight (LOS) environments due to increased Rician factors, which affects the performance of spatial multiplexing MIMO systems used in broadcast or multicast communications.
Innovation Solution
A transmission method and device that regularly change the phase of modulated signals while using a fixed precoding matrix, improving reception quality in LOS environments by adapting to direct wave conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If spatial multiplexing MIMO systems are used in broadcast or multicast communications, then data transmission capacity is improved, but reception quality deteriorates in Line-Of-Sight environments due to increased Rician factors
Solution Approach 1:
The patent applies dynamics by regularly changing the phase of modulated signals in LOS environments. The phase changing means dynamically adjusts signal parameters (phase rotation) based on detection of LOS conditions, allowing the system to adapt to direct wave interference while maintaining spatial multiplexing benefits. This dynamic adjustment resolves the contradiction by making the transmission system flexible rather than fixed.
Solution Approach 2:
The patent changes physical parameters of the transmitted signal by applying phase rotation to modulated signals when LOS conditions are detected. This parameter change (phase modification) directly addresses the Rician factor impact by altering signal characteristics to mitigate direct wave interference, thereby improving reception quality without sacrificing transmission capacity.
2Device complexity
If a fixed precoding matrix is used for MIMO transmission, then system complexity is reduced, but reception quality in LOS environments deteriorates due to direct wave interference
Solution Approach 1:
The system maintains a fixed precoding matrix for most operations to keep complexity low, but introduces dynamic phase changing specifically for LOS conditions. This selective dynamics approach balances complexity and performance by applying complexity-reducing fixed structure where possible while adding adaptivity only when needed for LOS mitigation.
Solution Approach 2:
The patent implements periodic or regular phase changing of modulated signals in LOS environments. This periodic action systematically applies phase rotation at regular intervals or for specific signal blocks, providing consistent mitigation of direct wave interference without requiring continuous complex adaptation, thus maintaining relatively low system complexity.
3Reliability
If phase changing is regularly applied to modulated signals, then reception quality in LOS environments is improved, but device complexity increases due to additional signal processing
Solution Approach 1:
The patent applies phase changing as a preliminary processing step before transmission in LOS environments. By pre-rotating the phase of modulated signals based on detected LOS conditions, the system prepares signals to be more resilient to direct wave interference, improving reception quality without requiring complex real-time processing at the receiver side.
Solution Approach 2:
The system uses feedback from LOS detection to control phase changing operations. The reception device detects LOS conditions and communicates this information back to the transmission device, which then applies appropriate phase changing. This feedback mechanism enables intelligent, condition-based phase adjustment rather than blind processing, optimizing the balance between reception quality improvement and processing complexity.
Data Source
AI summary
Provided is control information related to polarizations of antennas for MISO communication. The control signal generator generates polarization information indicating whether antennas used for transmission by MISO have only a first polarization or have a second polarization as well as the first polarization. With this structure, the present invention allows for the use of combinations of SISO, MISO and MIMO, taking the polarization of antennas. Furthermore, the present invention enables the receiver to reduce the power consumption.