Uplink Resource Allocation for OTFS Modulation

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Solution Overview

Problem

Current wireless communication networks face challenges in managing high data traffic and providing quality of service due to bandwidth limitations, particularly in uplink transmissions, where peak to average power ratio (PAPR) issues affect power efficiency and non-linearity, leading to suboptimal performance in next-generation wireless technologies.

Innovation Solution

The implementation of an Orthogonal Time Frequency Space (OTFS) modulation scheme for uplink transmissions, which allocates resources in the delay-Doppler domain, reducing PAPR and improving bandwidth utilization by spreading signals across time and frequency, thereby enhancing power efficiency and reducing interference.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If conventional uplink transmission schemes are used, then bandwidth utilization is achieved, but peak to average power ratio (PAPR) increases leading to power inefficiency and non-linearity

Engineering Contradiction:
Improvepower efficiencyVSAvoidpeak to average power ratio
Core Design Contradiction:
Use of energy by moving objectVSObject-generated harmful factors

Solution Approach 1:

The patent transforms the resource allocation from conventional time-frequency domain to delay-Doppler domain, adding a dimensional transformation approach. By performing OTFS transformation, signals are mapped to a new domain where resource elements are organized in terms of delay and Doppler shift rather than time and frequency, fundamentally changing how transmission resources are structured and allocated

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Productivity

If signals are concentrated in specific time-frequency resources, then transmission efficiency is improved, but interference increases and time-frequency diversity is not exploited

Engineering Contradiction:
ImprovethroughputVSAvoidinterference
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent spreads signals across the entire time-frequency grid by transforming resource allocations from delay-Doppler domain to time-frequency domain. Each resource element in delay-Doppler domain corresponds to a spread signal across multiple time-frequency points, achieving both high throughput and reduced interference through time-frequency diversity

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent divides transmission resources into discrete resource elements in the delay-Doppler domain, allowing independent allocation and control. This segmentation enables precise resource management while the OTFS transformation ensures each segmented resource contributes to overall diversity and interference reduction

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3520310B1Uplink user resource allocation for orthogonal time frequency space modulation
Publication Date: 2021.10.27 COHERE TECHNOLOGIES INC
  • EP3520310B1 patent drawingFigure 1
  • EP3520310B1 patent drawingFigure 2A
  • EP3520310B1 patent drawingFigure 2B

AI summary

A method of reducing peak to average power ratio of uplink transmission includes, assigning a slice of transmission resource to uplink transmission from a user equipment, where all resource elements in the slice have a same Doppler value, mapping data to the slice, performing orthogonal time frequency space transformation to generate time-frequency domain data and processing the time-frequency domain data for transmission.