Precoding Matrix Design for Cross-Polarized Antennas
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing multi-antenna transmission systems, particularly in LTE and LTE-A, face performance degradation due to the mismatch between the conventional co-located antenna configuration-based precoding matrices and the spatial autocorrelation matrices of distributed or large-spacing cross-polarized antennas, leading to suboptimal precoding performance and system throughput.
Innovation Solution
The method involves selecting and feeding back first and second precoding matrix indicators that correspond to block diagonal matrices with Hermitian sub-matrices, allowing the receiving end device to determine a third precoding matrix that matches the transmit spatial autocorrelation matrix of cross-polarized or distributed antennas, enhancing precoding performance and system throughput.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a conventional co-located antenna configuration-based precoding matrix is used, then the design is simple and compatible with existing systems, but the precoding performance degrades when applied to distributed or large-spacing cross-polarized antenna configurations
Solution Approach 1:
The codebook is segmented into multiple codebook groups, each designed for specific antenna configurations (co-located, distributed, or cross-polarized). The receiving device selects appropriate codebook groups based on the antenna configuration, enabling optimized precoding matrices for each scenario while maintaining overall system compatibility.
Solution Approach 2:
The system dynamically adapts the codebook selection and precoding matrix based on the antenna configuration and channel conditions. The receiving device determines which codebook group to use and feeds back the appropriate PMI, allowing the precoding matrix to be optimized in real-time for the specific antenna deployment scenario.
2Device complexity
If a single codebook is used for all antenna configurations, then the system complexity is low, but the precoding matrix cannot match the transmit spatial autocorrelation matrix for distributed or cross-polarized antennas
Solution Approach 1:
The codebook structure is designed to be universal across different antenna configurations while providing configuration-specific optimizations. Multiple codebook groups share a common framework, allowing the system to maintain low complexity through standardized procedures while achieving high matching accuracy by selecting the appropriate codebook group for each antenna configuration.
Solution Approach 2:
The system changes key parameters of the codebook (such as the structure of precoding matrices and the spatial correlation characteristics) based on the antenna configuration. Different codebook groups use different parameter settings that match the spatial characteristics of co-located, distributed, or cross-polarized antennas, enabling accurate matching without excessive complexity.
3Ease of operation
If existing codebooks are used without modification, then implementation is straightforward, but the precoding performance degrades for distributed and large-spacing cross-polarized antenna configurations
Solution Approach 1:
The codebook is pre-configured with multiple codebook groups, each optimized for specific antenna configurations. The receiving device performs preliminary assessment of the antenna configuration and selects the appropriate codebook group before precoding operations, ensuring optimal performance without requiring complex real-time adaptations during transmission.
Solution Approach 2:
The system implements feedback mechanisms where the receiving device feeds back the selected PMI and codebook group information to the transmitting device. This feedback enables the transmitting device to apply the correct precoding matrix from the appropriate codebook group, ensuring high precoding performance while maintaining straightforward implementation through standardized feedback procedures.
Data Source
Figure 1~2
Figure 3~5
AI summary
Embodiments of the present invention provide a method, an apparatus and a system for multi-antenna transmission, wherein a third precoding matrix determined by a sending end device is a function of a first precoding matrix and a second precoding matrix. That the first precoding matrix has a block diagonal structure and that sub-matrices corresponding to two blocks are Hermitian matrices enable the above-mentioned third precoding matrix to match with a transmit spatial autocorrelation matrix of a cross-polarized antenna or a distributed antenna, thereby enhancing precoding performance and improving system throughput effectively.