Transport Block Size Quantization for Low-Latency URLLC Links

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current LTE and NR communication systems fail to effectively support low-latency and high-reliability communication, particularly in ultra-reliable and low-latency communication (URLLC) scenarios, due to issues with transport block size (TBS) determination leading to high effective code rates greater than 0.95, which results in decoding errors and increased system latency.

Innovation Solution

A data communication processing method and device that acquires a modulation order and target code rate, calculates an intermediate number of information bits, quantizes them, and determines a transport block size (TBS) from a one-dimensional TBS table, ensuring low-latency and high-reliability communication by optimizing code rate and resource allocation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If high-order modulation with higher transmission rate is used, then system throughput is improved, but communication reliability deteriorates in deep fading channels

Engineering Contradiction:
Improvesystem throughputVSAvoidcommunication reliability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent implements dynamic adaptation by allowing the terminal to select from multiple CQI tables based on channel conditions and service requirements. The network can configure different CQI tables (e.g., first CQI table for eMBB, second CQI table for URLLC) and the terminal dynamically switches between them, enabling the system to adapt modulation and coding schemes in real-time to balance throughput and reliability.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the CQI representation parameters by introducing multiple CQI tables with different mappings from CQI indices to modulation and coding parameters. The network configures which CQI table to use via RRC signaling, and the terminal reports CQI based on the configured table, effectively changing the parameter mapping to optimize for different service scenarios.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If low-order modulation with larger redundancy is used, then communication reliability is ensured, but system throughput improvement is restricted

Engineering Contradiction:
Improvecommunication reliabilityVSAvoidsystem throughput
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent enables dynamic selection between different CQI tables that represent different reliability-throughput trade-offs. For reliable communication, the network can configure a conservative CQI table (second CQI table) that maps CQI indices to more robust modulation and coding schemes. The terminal dynamically uses this configured table for CQI reporting, allowing the system to prioritize reliability when needed while maintaining the capability for high throughput when channel conditions permit.

Inventive Principle:
Principle #15Dynamics

3Productivity

If TBS is calculated at higher MCS level, then transmission rate is improved, but effective code rate exceeds 0.95 causing decoding errors and increased latency

Engineering Contradiction:
Improvetransmission rateVSAvoiddecoding accuracy
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent implements feedback mechanisms where the terminal reports CQI to the network based on the configured CQI table, and the network uses this feedback to select appropriate MCS levels and TBS values. The feedback loop ensures that the effective code rate remains within acceptable ranges (below 0.95) by adjusting the CQI table configuration and MCS selection based on reported channel quality, preventing decoding errors while maintaining high transmission rates when possible.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent performs preliminary configuration of the CQI table via RRC signaling before data transmission. The network pre-configures the appropriate CQI table (first or second) based on service requirements (eMBB or URLLC), and the terminal uses this pre-configured table for CQI reporting and the network uses it for MCS selection, ensuring that the effective code rate is kept within acceptable ranges before transmission begins, avoiding decoding errors.

Inventive Principle:
Principle #10Preliminary action

4Reliability

If retransmission processing is performed due to decoding errors, then communication reliability is maintained, but system latency increases significantly

Engineering Contradiction:
Improvecommunication reliabilityVSAvoidsystem latency
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent performs preliminary configuration of the CQI table via RRC signaling before data transmission. The network pre-configures the appropriate CQI table (first or second) based on service requirements (eMBB or URLLC), and the terminal uses this pre-configured table for CQI reporting and the network uses it for MCS selection, ensuring that the effective code rate is kept within acceptable ranges before transmission begins, avoiding decoding errors.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements dynamic adaptation by allowing the terminal to select from multiple CQI tables based on channel conditions and service requirements. The network can configure different CQI tables (e.g., first CQI table for eMBB, second CQI table for URLLC) and the terminal dynamically switches between them, enabling the system to adapt modulation and coding schemes in real-time to balance throughput and reliability.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP4224754B1Data communication processing method and device
Publication Date: 2024.08.21 ZTE CORP
  • EP4224754B1 patent drawingFigure 1
  • EP4224754B1 patent drawingFigure 2~3A
  • EP4224754B1 patent drawingFigure 3B~3C

AI summary

Provided are a data communication processing method and device. The method includes: acquiring a modulation order and a target code rate; calculating an intermediate number Ninfo of information bits at least according to a total number of resource elements, the modulation order and the target code rate; quantizing the intermediate number Ninfo of the information bits to obtain the quantized intermediate number N'info ; determining a transport block size (TBS) according to the quantized intermediate number N'info.