Synchronization Signal Block Transmission in Unlicensed FR2 Bands
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a need for efficient and reliable SSB transmission in the high frequency band from 52.6 GHz to 71 GHz, which includes both licensed and unlicensed frequencies, with minimal changes to the existing NR FR2 technical specification, due to the presence of the 60 GHz unlicensed band and interference from other systems like WiGig.
Innovation Solution
A terminal and base station configuration that includes a reception unit for synchronization signal blocks in the unlicensed band, using a control unit to identify candidate positions for SSB transmission based on the demodulation reference signal sequence and payload of the broadcast channel, allowing for efficient and reliable SSB transmission with up to 64 beams and various subcarrier spacings, and adapting the SSB index and QCL parameters for optimal operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If SSB transmission is extended to unlicensed band (52.6 GHz to 71 GHz), then frequency band coverage is improved, but interference from other systems (e.g., WiGig) increases
Solution Approach 1:
The patent applies preliminary action by performing Listen-Before-Talk (LBT) procedure before SSB transmission in unlicensed bands. The base station checks channel availability and identifies candidate positions for SSB transmission in advance, ensuring the channel is free from interference before transmitting synchronization signals. This prevents collision with other systems like WiGig and ensures reliable SSB delivery.
2Reliability
If multiple candidate positions for SSB transmission are supported, then transmission reliability is improved, but device complexity increases
Solution Approach 1:
The patent segments the SSB transmission process by defining multiple candidate positions (e.g., 4 or 8 positions) within a burst set, where each position can independently carry SSB transmissions. The terminal device identifies these segmented candidate positions and attempts reception at each position separately. This segmentation improves reliability through diversity while keeping individual position processing simple and manageable.
3Adaptability or versatility
If SSB transmission uses extended frequency band with multiple subcarrier spacings, then adaptability is improved, but measurement precision deteriorates
Solution Approach 1:
The patent applies local quality by configuring different subcarrier spacings (SCS) for different candidate positions within the SSB burst set. Each candidate position can use a specific SCS value (e.g., 60 kHz, 120 kHz, or 240 kHz) optimized for its local frequency band conditions. The terminal device is configured with position-specific SCS information, allowing precise frequency measurements and synchronization at each local position while maintaining overall system adaptability across the extended 52.6 GHz to 71 GHz band.
Data Source
AI summary
A terminal includes a reception unit that receives a synchronization signal block in an unlicensed band of a high frequency band higher than or equal to a frequency band of a frequency range 2 (FR2), the FR2 being in a range including a frequency range 1 (FR1) that is a low frequency band and the FR2 that is a high frequency band in a new radio (NR) system; and a control unit that identifies an index of a candidate position for transmitting the synchronization signal block based on a sequence of a demodulation reference signal of a broadcast channel included in the synchronization signal block and a payload of the broadcast channel.