MIMO Antenna Polarization Diversity for Space Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
MIMO systems require multiple antennas for each subchannel, leading to space inefficiency and decorrelation challenges, especially in mobile devices where large antenna spacings are necessary for effective space diversity.
Innovation Solution
Assigning different polarizations to signals on subchannels and using a common antenna with a control facility to alter polarizations synchronically or randomly, employing an antenna array with densely neighboring partial antennas, such as a cross dipole, to achieve decorrelation without the need for multiple antennas.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple antennas are used for each subchannel to achieve decorrelation, then the reliability of MIMO sub channels is improved, but the device complexity and space requirements increase
Solution Approach 1:
The patent changes the polarization parameter of signals transmitted on different subchannels. By assigning different polarizations (e.g., horizontal, vertical, circular) to different subchannels, the system achieves decorrelation without requiring multiple physically separated antennas, thus resolving the contradiction between reliability and device complexity
Solution Approach 2:
The patent transitions from spatial diversity (using multiple antennas separated in space) to polarization diversity (using different polarization dimensions). This dimensional shift allows the system to achieve the same decorrelation effect without increasing the physical number of antennas, addressing the space efficiency problem
2Reliability
If large antenna spacings are used to achieve effective space diversity, then the decorrelation of sub channels is improved, but the area occupied by the antenna system increases
Solution Approach 1:
Instead of changing the spatial parameter (antenna spacing), the patent changes the polarization parameter of the signals. This allows decorrelation to be achieved through polarization differentiation rather than spatial separation, thereby reducing the required antenna system area while maintaining space diversity effectiveness
3Reliability
If one antenna is assigned to each MIMO sub channel with unchanged orthogonal polarization, then the reliability is improved, but the quantity of antennas required increases
Solution Approach 1:
The patent merges multiple subchannel signals with different polarizations into a single antenna system. Instead of requiring separate antennas for each subchannel, the invention combines them in the polarization domain, reducing the total quantity of antennas while preserving sub channel independence through polarization orthogonality
Solution Approach 2:
A single antenna is made multi-functional by enabling it to transmit and receive multiple polarizations simultaneously. This universal antenna can handle multiple MIMO subchannels with different polarizations, eliminating the need for dedicated antennas for each subchannel and reducing the overall antenna quantity
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 approach reduces the correlation between subchannels, achieving decorrelation similar to spatially distributed antennas with a single antenna, thereby optimizing space usage and reducing the number of required antennas, enhancing MIMO performance in mobile communications.
Implementation Method 1
different polarizations are assigned to the signals to be transmitted and received on the sub channels
Data Source
AI summary
A method and device for operating MIMO air interfaces in mobile communications systems, according to which a radio signal is transmitted by a transmitting device via a MIMO channel comprising a number of m subchannels and is received by a receiving device having n antennas. Different polarizations are assigned to the signals to be transmitted on the subchannels, and the signals are supplied to a common antenna.