Type-II MIMO Precoding Matrix Cycling for DMRS Bundling

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Solution Overview

Problem

Existing wireless communication systems, particularly 5G NR, face challenges in improving MIMO operations and precoding efficiency, especially in managing channel state information and resource block/resource element precoding for data channel transmission.

Innovation Solution

A semi-open-loop MIMO scheme is introduced with resource element/resource block-level non-transparent precoder cycling based on Type-II codebook, allowing for DMRS bundling while separately precoding data REs/RBs with known vectors, combining open-loop transmit diversity and receiver-transparent precoder cycling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If resource block-level precoding is applied to improve data channel transmission efficiency, then precoding efficiency is improved, but DMRS bundling capability deteriorates

Engineering Contradiction:

Improveprecoding efficiencyVSAvoidDMRS bundling capability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent segments the resource blocks into different groups (first resource blocks and second resource blocks) with different precoding application rules. DMRS-associated resource blocks maintain bundling while data resource blocks allow individual precoding, resolving the contradiction between precoding efficiency and DMRS bundling capability

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different quality treatments are applied to different parts of the resource allocation. Resource blocks containing DMRS maintain homogeneous precoding for reliable channel estimation, while other resource blocks apply optimized precoding for improved data transmission efficiency

Inventive Principle:

Principle #3Local quality

2Measurement precision

If channel state information feedback is increased to improve precoding accuracy, then precoding accuracy is improved, but feedback overhead increases

Engineering Contradiction:

Improveprecoding accuracyVSAvoidfeedback overhead

Core Design Contradiction:

Measurement precisionVSLoss of information

Solution Approach 1:

The patent applies partial precoding feedback by only requiring channel state information feedback for resource blocks that benefit from precoding, rather than full feedback for all resource blocks. This reduces feedback overhead while maintaining sufficient precoding accuracy for data transmission

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The system changes the feedback parameter requirements based on the resource block type and transmission conditions. Different feedback granularities are used for different resource blocks, optimizing the balance between precoding accuracy and feedback overhead

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS12531607B2Semi-open-loop MIMO transmission based on type-II precoding matrices

Publication Date: 2026.01.20 QUALCOMM INC

AI summary

Aspects presented herein may improve multiple-input multiple-output (MIMO) operations by providing a semi-open-loop MIMO scheme with a higher granularity. In one aspect, a network entity formulates, based on wideband (WB) channel state information of a channel from a user equipment (UE), a set of precoding matrices to be applied on a set of resource blocks (RBs) or a set of resource elements (REs) for a data channel transmission on the channel. The network entity precodes the set of RBs or the set of REs for the data channel transmission on the channel with the formulated set of precoding matrices and a set of phase values in a cycling manner. The network entity transmits, via the channel, an indication of the set of precoded RBs or the set of precoded REs.