Dual-Level Codebook for Dual-Polarized Antenna Precoding
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Solution Overview
Problem
Current codebooks for dual-polarized multi-antenna systems in wireless communication systems, such as LTE-A, face performance losses due to inadequate consideration of channel distribution characteristics and increased computation complexity, particularly when transitioning from Rel-8 LTE systems to systems with more antennas.
Innovation Solution
A dual-level codebook is designed using a base codebook and a transform codebook, where precoders are constructed via Kronecker tensor products of matrices, optimizing the tradeoff between correlated and non-correlated channels to minimize performance loss and maintain compatibility with existing systems.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a traditional codebook is used for dual-polarized multi-antenna systems, then system compatibility is maintained, but precoding performance is degraded due to inadequate consideration of channel distribution characteristics
Solution Approach 1:
The codebook is segmented into two independent components: a base codebook (W1) that captures the dominant channel distribution characteristics, and a transform codebook (W2) that provides fine-grained adjustments. This segmentation allows each component to be optimized for its specific function, improving overall precoding performance while maintaining manageable complexity through modular design.
Solution Approach 2:
The patent combines two different codebook structures (base codebook and transform codebook) into a composite dual-level codebook system. The base codebook uses a specific structure optimized for dual-polarized antenna channels, while the transform codebook adds complementary characteristics, creating a composite solution that leverages the strengths of both components to achieve superior performance.
2Productivity
If the number of transmit antennas is increased to improve system throughput, then capacity increases, but codebook design complexity and computation overhead increase significantly
Solution Approach 1:
By segmenting the codebook into base and transform components, the patent enables scalable design for different antenna configurations. The base codebook can be designed once for a given antenna count, and the transform codebook provides flexible adaptations, reducing the overall design complexity compared to creating entirely new codebooks for each antenna configuration.
Solution Approach 2:
The dual-level codebook structure introduces dynamic adaptability through the transform codebook, which can adjust the precoding matrices based on specific channel conditions and antenna configurations. This dynamic approach allows the system to optimize performance for increased antenna counts without requiring complete redesign of the entire codebook structure.
3Loss of time
If quantized channel information is used to reduce feedback overhead, then feedback delay is reduced, but transmission optimization capability is limited
Solution Approach 1:
The patent changes the parameter representation in the codebook by using a structured dual-level format with specific mathematical relationships between base and transform components. This parameter transformation allows for more efficient quantization and feedback while preserving the essential channel characteristics needed for effective transmission optimization, achieving a better balance between feedback overhead and optimization capability.
Data Source
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AI summary
Embodiments of the present invention provide a method for transmitting information in a multi-antenna system. The method may include: a transmitting end receives information transmitted by a receiving end, wherein the information includes information of index of a precoder; the transmitting end selects a precoder from a two-layered codebook based on the information of the index of the precoder; the transmitting end precodes to-be-transmitted data by using the precoder; the transmitting end transmits the precoded data to the receiving end. The technical scheme of the present invention obtains codebooks most matching with channel distribution characteristics of dual-polarized antennas and minimizes performance loss brought by codebook quantization to remarkably improve the performances of precoding systems.