SSB-Based MIMO Channel Reporting for Faster Beam Refinement

Solution Overview

Problem

Existing CSI reporting settings in communications networks based on the NR air interface are inadequate for efficiently acquiring accurate MIMO channel information, particularly in scenarios with multiple-input multiple-output characteristics, leading to suboptimal beam selection and increased latency due to the need for additional downlink reference signal transmissions.

Innovation Solution

A method and system for triggering user equipment to report MIMO channel information based on measurements made on SSB reference signals, allowing direct reporting of metrics such as CQI, rank information, and PMI, thereby reducing the number of steps required for beam refinement and minimizing polarization mismatch.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If traditional CSI reporting settings are used, then channel state information can be obtained, but the acquisition process is time-consuming and requires additional downlink reference signal transmissions

Engineering Contradiction:

ImproveMIMO channel information accuracyVSAvoidbeam refinement time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The patent applies preliminary action by configuring the UE to perform MIMO channel information measurements on SSB reference signals in advance, before actual beam refinement is needed. The UE prepares and stores measurement results (CQI, rank information, PMI) that can be directly utilized during beam selection, eliminating the need for time-consuming additional reference signal transmissions and multiple measurement cycles.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent makes the SSB reference signal serve multiple functions: it simultaneously provides downlink synchronization, system information broadcasting, and MIMO channel state information measurement. By configuring the UE to extract MIMO channel information from SSB signals, the system eliminates the need for separate CSI-RS signals, thereby reducing time loss while maintaining measurement precision.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Measurement precision

If additional downlink reference signal transmissions are performed, then accurate channel estimation can be achieved, but polarization mismatch increases and user throughput decreases

Engineering Contradiction:

Improvechannel estimation accuracyVSAvoiduser throughput

Core Design Contradiction:

Measurement precisionVSProductivity

Solution Approach 1:

The patent makes the SSB reference signal serve multiple functions: it simultaneously provides downlink synchronization, system information broadcasting, and MIMO channel state information measurement. By configuring the UE to extract MIMO channel information from SSB signals, the system eliminates the need for separate CSI-RS signals, thereby reducing time loss while maintaining measurement precision.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent changes the parameter configuration by enabling the UE to report MIMO channel information metrics (CQI, rank information, PMI) based on SSB reference signal measurements. This parameter change allows the system to obtain accurate channel estimation without requiring additional reference signal transmissions, thus maintaining productivity while improving measurement precision.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If SSB reference signals are used for MIMO channel information, then beam selection reliability improves, but the system requires dual-polarized transmission capability

Engineering Contradiction:

Improvebeam selection reliabilityVSAvoiddual-polarized transmission requirement

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent makes the SSB reference signal serve multiple functions: it simultaneously provides downlink synchronization, system information broadcasting, and MIMO channel state information measurement. By configuring the UE to extract MIMO channel information from SSB signals, the system eliminates the need for separate CSI-RS signals, thereby reducing time loss while maintaining measurement precision.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS12580612B2Triggering of report configuration for reportings of MIMO channel information from user equipment

Publication Date: 2026.03.17 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)

AI summary

There is provided mechanisms for triggering user equipment to use a report configuration. A method is performed by a network node. The method comprises triggering user equipment to use a report configuration. According to the report configuration the user equipment are to report at least one metric pertaining to MIMO channel information back to the network node. According to the report configuration the at least one metric is to be based on measurements made by the user equipment on an SSB reference signal. The method comprises receiving reportings of the MIMO channel information from the user equipment in accordance with the triggered report configuration.