DCI Timing Determination for Semi-Static TDD Configurations

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current 5G NR scheduling methods face inefficiencies in DCI signaling, particularly when handling dynamic and semi-static TDD uplink-downlink allocations, which can lead to suboptimal resource usage.

Innovation Solution

The method determines the timing for scheduled transmissions or receptions in wireless devices based on whether they are configured with semi-static or dynamic TDD uplink-downlink allocations, using specific functions to calculate the set of slots or symbols for data transmission, thereby optimizing DCI signaling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If dynamic TDD scheduling is used to maximize resource flexibility, then adaptability is improved, but DCI signaling overhead increases

Engineering Contradiction:

Improvescheduling flexibilityVSAvoidDCI signaling overhead

Core Design Contradiction:

Adaptability or versatilityVSLoss of information

Solution Approach 1:

The patent segments the TDD configuration into two parts: semi-static uplink-downlink allocation patterns (configured via RRC signaling) and dynamic slot timing adjustments (indicated via DCI). This segmentation allows the bulk of the TDD structure to be predetermined, reducing the information needed in DCI, while still permitting dynamic adjustments when needed.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent applies preliminary action by pre-configuring the semi-static uplink-downlink allocation patterns through RRC signaling before actual data transmission. This preliminary configuration establishes the fundamental TDD structure, so that subsequent DCI messages only need to indicate specific slot timing adjustments rather than transmitting complete TDD configuration information.

Inventive Principle:

Principle #10Preliminary action

2Loss of information

If semi-static TDD allocation is used to reduce DCI signaling, then DCI overhead is reduced, but scheduling flexibility deteriorates

Engineering Contradiction:

ImproveDCI signaling overheadVSAvoidscheduling flexibility

Core Design Contradiction:

Loss of informationVSAdaptability or versatility

Solution Approach 1:

The patent introduces dynamics into the semi-static TDD allocation by allowing the network to dynamically adjust the timing of scheduled slots or symbols through DCI messages. While the uplink-downlink allocation pattern itself remains semi-static, the actual transmission timing can be flexibly adjusted on a per-scheduling-instance basis, combining the benefits of both static and dynamic approaches.

Inventive Principle:

Principle #15Dynamics

3Measurement precision

If complete TDD configuration is transmitted in DCI, then scheduling accuracy is improved, but DCI resource consumption increases

Engineering Contradiction:

Improvescheduling accuracyVSAvoidDCI resource consumption

Core Design Contradiction:

Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent extracts the essential TDD configuration information (uplink-downlink allocation patterns) from the DCI messages and places it in the semi-static RRC configuration. This extraction leaves DCI messages with only the critical timing adjustment information, maintaining scheduling accuracy while dramatically reducing DCI resource consumption.

Inventive Principle:

Principle #2Taking out (Extraction)

4Productivity

If DCI resources are minimized, then network efficiency is improved, but timing determination complexity increases

Engineering Contradiction:

Improvenetwork efficiencyVSAvoidtiming determination complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent introduces an intermediary layer of semi-static RRC configuration that mediates between the network scheduler and the UE timing determination. This intermediary contains the uplink-downlink allocation patterns, allowing the UE to efficiently determine timing by combining this pre-configured information with the compact DCI timing indicators, rather than processing complex timing information directly from DCI alone.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS11310784B2Configuration-dependent DCI timing

Publication Date: 2022.04.19 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)

AI summary

The disclosure relates to a method of operating a wireless device. The method comprises receiving (10), from a network node, control information indicating a timing of a scheduled transmission or reception. The method further comprises determining (20) at least one slot or symbol for the scheduled transmission or reception based on the control information indicating the timing, wherein the determining is dependent on whether the wireless device is configured with a semi-static time division duplex, TDD, uplink-downlink allocation or not. The method also comprises performing (30) the scheduled transmission or reception in the determined at least one slot or symbol.