Secondary Interface Switching for Low-Latency Uplink in Unlicensed Spectrum
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for improving uplink transmission in the unlicensed spectrum fail to effectively address channel access delays, which are critical for low-latency applications like URLLC in factory automation and motion control.
Innovation Solution
A system with a Basic Service Set (BSS) comprising an Access Point (AP) and Stations (STA) that utilize both primary and secondary wireless interfaces. When the primary channel is unavailable, the STA switches to the secondary interface to transmit messages to the AP, allowing for dynamic scheduling and channel selection to minimize latency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If LBT operation is performed in unlicensed spectrum, then channel access reliability is improved, but transmission latency increases
Solution Approach 1:
The system performs preliminary channel sensing and identifies alternative channels in advance. When the primary channel becomes unavailable during LBT countdown, the STA has pre-identified secondary channels ready for immediate switching, eliminating the need for reactive channel search and reducing latency while maintaining reliable channel access through the LBT framework
Solution Approach 2:
The patent introduces a secondary wireless interface as an intermediary channel when the primary channel is unavailable. This intermediary channel allows RLLC traffic to continue transmission without waiting for the primary channel to become available, thus reducing latency while the LBT operation continues on the primary channel to maintain reliability
2Adaptability or versatility
If secondary wireless interface is added for channel switching, then channel access flexibility is improved, but device complexity increases
Solution Approach 1:
The system segments the channel access function into primary channel (for normal LBT operation) and secondary channel (for backup and low-latency traffic). This segmentation allows the device to maintain the standard LBT process on the primary channel while having a dedicated alternative path for critical traffic, improving flexibility without requiring complete redundancy of the entire communication stack
Solution Approach 2:
The patent implements a simplified copy of the wireless interface functionality specifically for secondary channel operation. Rather than duplicating the entire complex wireless stack, the system creates a streamlined secondary interface that handles only the essential functions needed for backup channel access and RLLC traffic, reducing the complexity overhead compared to full interface duplication
Data Source
AI summary
A system in wireless network including an Access Point utilizing at least an unlicensed first wireless interface; a Station utilizing at least a first unlicensed wireless interface, transmitting in uplink to the AP; Said at least one STA further includes a secondary wireless interface different from the first unlicensed wireless interface, said STA is configured to, determine that transmission of a message be in a secondary wireless interface of the STA when it is utilized for Reliable and Low Latency Communication RLLC data transmission, generate a message and then transmit the message to a serving AP. Said AP is configured to, when receiving the message from the STA, determine whether information will be generated based on the message received from the STA, generate at least scheduling information and transmit the generated information to the STA.