Half-Duplex Wireless Packet Re-Encoding for Collision Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In half-duplex based wireless communication systems, particularly in V2X communication, the use of larger packet sizes and longer transmission times leads to increased data losses due to the inability of user equipment (UEs) to receive data during transmission, resulting in collisions and inefficiencies.

Innovation Solution

User equipment (UEs) re-encode longer packets with a higher modulation order and coding rate to form shorter packets, which are then transmitted in multiple repetitions to improve reception and reduce data losses, with the number of repetitions adjusted based on the required communication range and signal-to-noise ratio (SNR) to accommodate varying packet sizes and ranges.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of stationary object

If larger packet sizes are used to support V2X communication requirements, then the transmission range is improved, but the transmission time increases leading to higher half-duplex losses

Engineering Contradiction:
Improvetransmission rangeVSAvoidtransmission time
Core Design Contradiction:
Area of stationary objectVSLoss of time

Solution Approach 1:

The patent divides a large data packet into multiple smaller transport blocks that can be transmitted separately. This segmentation allows the system to maintain the required transmission range through sufficient total data transmission while reducing the time each individual transmission occupies the half-duplex channel, thereby reducing half-duplex losses.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent employs periodic retransmissions of transport blocks at scheduled intervals. This periodic action ensures that even if some transmissions are lost due to half-duplex conflicts, the data can be retransmitted at subsequent opportunities, maintaining reliable communication without requiring excessively long initial transmission times.

Inventive Principle:
Principle #19Periodic action

2Quantity of substance

If longer transmission time is used to meet required transmission range, then more data can be transmitted, but packet losses increase due to half-duplex collisions

Engineering Contradiction:
Improvedata transmission volumeVSAvoidpacket delivery reliability
Core Design Contradiction:
Quantity of substanceVSReliability

Solution Approach 1:

The patent performs preliminary segmentation of data into multiple transport blocks before transmission. This preliminary action enables the system to transmit data in manageable units with built-in redundancy, allowing receivers to reconstruct the original data even if some transport blocks are lost due to half-duplex collisions during the extended transmission period.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent incorporates redundant transmissions and retransmission mechanisms as a cushion against potential packet losses. By preparing multiple copies and retransmission schedules in advance, the system compensates for the increased vulnerability to collisions that arises from longer transmission times in half-duplex mode.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

3Device complexity

If UEs transmit data in half-duplex mode, then device complexity is reduced, but data reception during transmission becomes impossible leading to collisions

Engineering Contradiction:
Improvedevice complexityVSAvoiddata reception reliability
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent segments data into multiple transport blocks that can be transmitted in sequence. This segmentation allows receiving UEs to potentially receive subsequent transport blocks even after missing earlier ones, maintaining reliability without requiring full-duplex capability or complex scheduling to avoid all collisions.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3881460B1Transmissions in a half duplex based wireless communication system
Publication Date: 2024.12.18 QUALCOMM INC
  • EP3881460B1 patent drawingFigure 1
  • EP3881460B1 patent drawingFigure 2
  • EP3881460B1 patent drawingFigure 3

AI summary

Methods, apparatuses, and computer-readable mediums for wireless communication include re-coding a first coded packet into a second coded packet, wherein the second coded packet includes less coded bits and has a higher modulation order than the first packet, generating one or more redundant versions of the second packet, and transmitting the second packet and the one or more redundant versions of the second packet at different times to a receiving user equipment.