Synchronization Signal Block Signaling for Shared Spectrum Access
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, user equipment (UE) operating in shared radio frequency spectrum bands face challenges in reliably performing single-shot detection and demodulation of synchronization signal blocks due to asynchronous transmissions across multiple base stations, which prevents effective combination of multiple received synchronization signal blocks for improved demodulation performance.
Innovation Solution
Base stations transmit a burst set of synchronization signal blocks with each block on a different beam, synchronizing their transmission times, and provide indicators within each block or as separate signals to the UE, including the time of access to the shared spectrum, current beam, and remaining blocks in the burst set, allowing the UE to determine its position within the burst set and continue listening accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If base stations perform clear channel assessment (CCA) to determine transmission timing in shared spectrum, then channel access reliability is improved, but transmission asynchrony increases preventing UE from combining multiple SS blocks
Solution Approach 1:
The base station performs CCA and determines the first SS block transmission timing in advance within the measurement window. The UE is provided with indication information about this predetermined timing, allowing the UE to prepare for single-shot detection at the correct time without requiring multiple attempts or combinations, thus resolving the contradiction between reliable channel access and transmission synchrony.
2Adaptability or versatility
If base stations transmit SS blocks asynchronously after CCA, then individual base station access flexibility is improved, but UE detection reliability deteriorates due to inability to combine multiple SS blocks
Solution Approach 1:
The base station provides indication information to the UE about the timing of the first SS block transmission within the measurement window. This feedback mechanism allows the UE to adapt its detection strategy to the asynchronous transmission schedule, enabling reliable single-shot detection without requiring transmission synchrony or the ability to combine multiple SS blocks.
3Speed
If UEs perform single-shot detection of SS blocks in shared spectrum, then detection speed is improved, but detection accuracy deteriorates compared to combining multiple SS blocks
Solution Approach 1:
The base station determines and indicates to the UE the precise timing of the first SS block transmission in advance. This allows the UE to perform single-shot detection at the optimal moment with maximum signal quality, achieving both fast detection speed and high detection accuracy without needing to combine multiple SS blocks.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Methods, systems, and devices for wireless communication are described. A base station may perform an access procedure to obtain access to a shared radio frequency spectrum band during a measurement window and generate a synchronization signal (SS) burst comprising a plurality of SS blocks. The base station may perform a beam sweeping first transmission of the SS burst over the shared radio frequency spectrum based at least in part on the access procedure. In the first transmission or a second transmission, the base station may transmit at least one of a first indication of a time of access to the shared radio frequency spectrum band with respect to the measurement window, a second indication of a transmission beam associated with the SS block, and a third indication of a quantity of remaining SS blocks from the plurality of SS blocks to follow the SS block in the measurement window.