Uplink Waveform Selection via MCS Tables

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Solution Overview

Problem

Current wireless communication systems, particularly in the context of 5G New Radio (NR), face challenges in efficiently switching between OFDM and DFTS-OFDM waveforms for uplink communications due to long reconfiguration times and potential throughput losses, especially when RRC signaling is used, leading to uncertainty in waveform selection and limited support for higher-order modulations.

Innovation Solution

A method and system for selecting waveforms based on Modulation and Coding Scheme (MCS) tables, allowing for resource-efficient switching between OFDM and DFTS-OFDM modulations by choosing indices and resource allocations that determine the appropriate waveform for transmission, with specific entries in the table indicating the use of either OFDM or DFTS-OFDM, depending on transport block size and resource allocation characteristics.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If RRC signaling is used for waveform switching, then waveform selection flexibility is improved, but reconfiguration time increases and throughput losses occur

Engineering Contradiction:

Improvewaveform selection flexibilityVSAvoidreconfiguration time

Core Design Contradiction:

Adaptability or versatilityVSLoss of time

Solution Approach 1:

The patent applies preliminary action by pre-configuring MCS tables with waveform indicators before communication occurs. The network node and wireless device both store multiple MCS tables with different waveform indicators (OFDM or DFTS-OFDM) already prepared, allowing immediate waveform switching without RRC reconfiguration delays.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements dynamics by enabling real-time waveform switching through MCS table selection based on current communication conditions. The wireless device can dynamically choose between different waveform indicators in the MCS table depending on transport block size, resource allocation, and channel conditions, allowing adaptive response without static RRC configuration delays.

Inventive Principle:

Principle #15Dynamics

2Adaptability or versatility

If RRC signaling is used for waveform switching, then waveform selection flexibility is improved, but throughput losses occur

Engineering Contradiction:

Improvewaveform selection flexibilityVSAvoidthroughput

Core Design Contradiction:

Adaptability or versatilityVSProductivity

Solution Approach 1:

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent maintains continuity of useful action by ensuring seamless waveform transitions through pre-synchronized MCS tables. Both network node and wireless device have identical MCS tables prepared in advance, allowing continuous data transmission without interruption or throughput loss during waveform switching events.

Inventive Principle:

Principle #20Continuity of useful action

3Productivity

If waveform switching is enabled, then communication efficiency is improved, but uncertainty in waveform selection increases

Engineering Contradiction:

Improvecommunication efficiencyVSAvoidwaveform selection certainty

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent applies feedback by using explicit waveform indicators in the MCS tables that provide clear information to the wireless device about which waveform to use. The network node selects specific MCS entries with defined waveform indicators, and the wireless device receives this feedback through downlink control information, eliminating uncertainty about waveform selection.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The patent uses parameter changes by varying the waveform indicator parameter within the MCS table structure. Different MCS entries contain different waveform indicators (OFDM or DFTS-OFDM), allowing the system to change the waveform parameter based on communication conditions while maintaining clear, unambiguous selection through the standardized MCS table format.

Inventive Principle:

Principle #35Parameter changes

4Adaptability or versatility

If multiple waveforms are supported, then modulation flexibility is improved, but device complexity increases

Engineering Contradiction:

Improvemodulation flexibilityVSAvoidwaveform handling complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent applies universality by using a single MCS table structure that handles multiple waveforms (OFDM and DFTS-OFDM) through different entries. Rather than requiring separate handling mechanisms for each waveform, the universal MCS table provides a unified interface that selects the appropriate waveform based on the indicated entry, reducing device complexity while maintaining flexibility.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS11799614B2Selection of waveform for uplink communications

Publication Date: 2023.10.24 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)

AI summary

A method, network node and wireless device for waveform selection are provided. A method includes selecting a waveform based on one of a modulation and coding scheme, MCS, a resource allocation, and transport block size, TBS, and transmitting using the selected waveform.