Sub-RB SRS Combining for Uplink Coverage and Channel Estimation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing wireless communication systems, particularly in 5G NR, face challenges in enhancing uplink coverage for user equipment at cell edges or coverage holes due to compatibility issues with NR UEs and weak channel estimation performance, leading to interference and inefficient resource allocation.

Innovation Solution

Implementing combinable sub-resource block (RB) sounding reference signal (SRS) transmission by configuring a group of sub-RB SRS signals at shifted frequency resources, allowing for multiplexing with full-RB SRS and improving channel estimation through coherent combining gains.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If full-RB SRS transmission is used to improve channel estimation performance, then coverage is enhanced, but resource allocation flexibility and interference management deteriorate

Engineering Contradiction:

Improvechannel estimation performanceVSAvoidresource allocation flexibility

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The resource block is segmented into multiple sub-RBs, allowing the SRS transmission to be divided into smaller frequency units. This segmentation enables flexible resource allocation where only the necessary sub-RBs are allocated for SRS transmission, improving resource allocation flexibility while maintaining adequate channel estimation performance through selective sub-RB transmission.

Inventive Principle:

Principle #1Segmentation

2Adaptability or versatility

If sub-RB SRS transmission is implemented to improve resource allocation flexibility, then adaptability improves, but channel estimation performance deteriorates

Engineering Contradiction:

Improveresource allocation flexibilityVSAvoidchannel estimation performance

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

Multiple sub-RB SRS transmissions are combined at the receiver side to form a complete channel estimation. The network entity receives SRS on multiple sub-RBs and combines them to achieve full-RB channel estimation performance. This merging approach maintains channel estimation reliability while allowing flexible allocation of individual sub-RBs.

Inventive Principle:

Principle #5Merging (Combining)

3Reliability

If SRS transmission is increased to enhance coverage, then uplink coverage improves, but interference increases

Engineering Contradiction:

Improveuplink coverageVSAvoidinterference

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

Different sub-RBs are allocated to different UEs based on local channel conditions and interference patterns. Instead of all UEs transmitting on the same full-RB resources, each UE transmits on specific sub-RBs tailored to its needs, reducing inter-UE interference while maintaining coverage enhancement through targeted sub-RB transmission.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS12494887B2Combinable a sub-resource block (RB) sounding reference signal (SRS) transmission for coverage enhancement

Publication Date: 2025.12.09 QUALCOMM INC

AI summary

The present disclosure relates to combinable a sub-resource block (RB) sounding reference signal (SRS) transmission for coverage enhancement. Specifically, a network entity may transmit, and a user equipment (UE) may receive a sub-RB SRS configuration message, and a transmit one or more sub-RB SRS. The UE may receive a sub-RB SRS configuration message and transmit one or more sub-RB SRS.