RIS-Assisted Initial Access for Non-Reciprocal Wireless Links
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless communication systems face challenges in establishing efficient initial access procedures, particularly in environments with blockage or non-reciprocal signal conditions, which affect the effectiveness of synchronization and random access channel processes.
Innovation Solution
The implementation of reconfigurable intelligent surfaces (RIS) to assist in wireless communication by transmitting and receiving synchronization signal blocks (SSBs) and physical random access channel (PRACH) transmissions, enabling beam management and selection of optimal communication paths through multiple transmission slots.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If reconfigurable intelligent surface (RIS) is used to assist wireless communication in blockage-prone environments, then signal reception and transmission reliability is improved, but device complexity and system configuration difficulty increase
Solution Approach 1:
The patent introduces a reconfigurable intelligent surface (RIS) as an intermediary component between the base station and user equipment. The RIS consists of multiple programmable reflecting elements that can dynamically adjust signal reflection characteristics to establish reliable communication paths through blockage-prone environments, thereby improving signal reception reliability without requiring complex multi-antenna systems at the endpoints
Solution Approach 2:
The RIS configuration is made dynamic through multiple transmission slots and beam management procedures. The system performs initial access in the first transmission slot, followed by beam refinement in subsequent slots, allowing the RIS to adapt its reflecting characteristics in real-time to maintain optimal signal paths, thus improving reliability while managing complexity through phased configuration
2Reliability
If multiple transmission slots are used for beam management and PRACH transmissions, then communication link optimization is improved, but access time and procedure duration increase
Solution Approach 1:
The patent performs preliminary beam management and RIS configuration actions in the first transmission slot during initial access. The base station establishes the initial communication link and configures the RIS before actual data transmission begins, so that subsequent communications can proceed more efficiently without repeated setup delays, thereby reducing overall access time while maintaining link optimization
3Measurement precision
If beam sweeping with multiple receive beams is performed over multiple PRACH transmission slots, then beam selection accuracy and communication quality are improved, but procedure complexity and signaling overhead increase
Solution Approach 1:
The beam sweeping procedure is segmented into distinct phases: initial access in the first transmission slot using a limited set of beams for basic connectivity, followed by beam refinement in subsequent slots using additional beams for optimization. This segmentation allows the system to achieve high beam selection accuracy while managing procedure complexity by breaking down the complex beam management task into manageable stages with different precision requirements
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enhances the reliability and efficiency of initial access procedures by improving signal reception and transmission, even in blockage-prone environments, thereby optimizing communication links between base stations and user equipment.
Implementation Method 1
receiving, from a base station and via a reconfigurable intelligent surface (RIS), a synchronization signal block (SSB)
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, from a base station and via a reconfigurable intelligent surface (RIS), a synchronization signal block (SSB) corresponding to a first SSB type configured for RIS-assisted procedures. The UE may select a random access channel (RACH) occasion including multiple physical random access channel (PRACH) transmission slots based at least in part on receiving the SSB corresponding to the first SSB type. The UE may transmit, to the base station, a PRACH communication in the multiple PRACH transmission slots of the RACH occasion. Numerous other aspects are described.