SRS Resource Allocation for Multi-Cell Channel Sounding

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Solution Overview

Problem

In LTE-A systems, channels of multiple cells cannot be sounded concurrently, leading to limitations in inter-cell interference reduction and feedback overhead for User Equipments (UEs), which hampers the performance of multi-point coordinated transmission.

Innovation Solution

Allocating a SRS resource to a UE in multiple cells for concurrent channel sounding, allowing the UE to transmit SRSs over these resources, thereby enabling the UE to sound channels of multiple cells, reduce feedback overhead, and improve system performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If SRS resources are allocated per cell with orthogonal configuration, then interference between cells is reduced, but channels of multiple cells cannot be sounded concurrently

Engineering Contradiction:
Improvechannel sounding capabilityVSAvoidsounding efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent combines SRS resources from multiple cells into a shared resource pool that can be allocated to UEs for concurrent multi-cell channel sounding. This merging approach allows a single UE to sound channels of multiple cells simultaneously using the same time-frequency resources, eliminating the limitation of sequential sounding while maintaining orthogonality through UE-specific resource allocation within the shared pool.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent creates a universal SRS resource pool that serves multiple cells simultaneously, allowing the same resource to be used for sounding channels of different cells. This multi-functional resource allocation enables the system to achieve both inter-cell interference coordination and concurrent multi-cell channel sounding by making SRS resources universally applicable across multiple cells rather than dedicating separate resources to each cell.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Reliability

If joint scheduling is implemented across multiple cells, then inter-cell interference is reduced, but feedback overhead for UEs increases

Engineering Contradiction:
Improvemulti-point coordinated transmission performanceVSAvoidfeedback overhead
Core Design Contradiction:
ReliabilityVSLoss of information

Solution Approach 1:

The patent enables the network to self-serve by obtaining channel state information from multiple cells through UE-transmitted SRS signals, eliminating the need for UEs to perform complex channel measurements and feedback reporting for multiple cells. The UE simply transmits SRS on allocated resources, and the network autonomously collects channel information from all participating cells, significantly reducing UE processing burden and feedback overhead while maintaining multi-point coordinated transmission capabilities.

Inventive Principle:
Principle #25Self-service

3Device complexity

If sequential channel sounding is performed for multiple cells, then resource allocation is simple, but system performance for multi-point transmission is limited

Engineering Contradiction:
Improveresource allocation complexityVSAvoidmulti-point coordinated transmission performance
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent introduces dynamic resource allocation within a shared SRS resource pool, where resources are flexibly assigned to UEs based on multi-cell channel sounding requirements. This dynamic approach allows the system to adapt resource allocation to concurrent sounding needs of multiple cells, enabling improved multi-point transmission performance while maintaining manageable complexity through standardized allocation procedures and UE-specific orthogonal resource assignment within the shared pool.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP2413622B1Method and device for transmitting sounding reference signal
Publication Date: 2014.10.15 CHINA ACAD OF TELECOMM TECH
  • EP2413622B1 patent drawingFigure 1~2
  • EP2413622B1 patent drawingFigure 3~4
  • EP2413622B1 patent drawingFigure 5~6

AI summary

A method and device for transmitting sounding reference signal (SRS). The method includes that: in at least two cells which new user equipment (UE) to perform uplink channel sounding, the SRS resources for performing sounding to cell are distributed to the UE; the UE is indicated to transmit the SRS on the distributed SRS resources. The method of the present invention can enable the UE to detect the channels of a plurality of and to be use in multipoint cooperative transmission, avoid the UE feeding back the channel information of a plurality of cells, and reduce the feedback overhead and improve the system performance.