RIS Uplink and Downlink Selection for High-Frequency Wireless Links
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electronic devices face challenges in supporting higher data rates due to over-the-air attenuation and line-of-sight requirements of high-frequency radio-frequency signals, limiting wireless communication performance.
Innovation Solution
Implementing reconfigurable intelligent surfaces (RIS) to reflect signals between a wireless base station and user equipment, optimizing signal beams using control and data radio access technologies to select the best RIS for uplink and downlink communications, reducing overhead through beam training.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If higher frequency radio-frequency signals are used to support higher data rates, then data rate is improved, but signal attenuation increases and line-of-sight requirements become more stringent
Solution Approach 1:
The patent introduces reconfigurable intelligent surfaces (RIS) as intermediary devices that reflect and redirect high-frequency signals between transmitter and receiver. These RIS surfaces act as mediators that enable signal propagation in non-line-of-sight conditions, thereby maintaining high data rates without suffering from direct over-the-air attenuation
Solution Approach 2:
The patent utilizes reflective surfaces positioned in three-dimensional space to create alternative signal paths. By deploying RIS at different spatial locations and orientations, the system adds dimensional flexibility to signal propagation, allowing high-frequency signals to reach destinations through reflected paths rather than direct line-of-sight
2Device complexity
If the same RIS is used for both uplink and downlink reflections, then device complexity is reduced, but wireless performance is limited due to suboptimal RSRP
Solution Approach 1:
The patent segments the RIS resources by assigning different RIS devices or different surface segments to uplink and downlink reflections. This segmentation allows each reflection path to be independently optimized for its specific direction and channel conditions, thereby maximizing RSRP for both uplink and downlink without requiring complex coordinated control of a single unified RIS
3Reliability
If exhaustive beam training is used to identify the best RIS for uplink and downlink, then wireless performance is optimized, but overhead is significantly increased
Solution Approach 1:
The patent performs preliminary beam training and RIS selection using control radio access technology before actual data transmission. By pre-identifying the optimal RIS devices for uplink and downlink using lower-overhead control signals, the system avoids the need for exhaustive beam training during data transmission, thereby reducing overhead while maintaining optimized wireless performance
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 wireless performance by reducing signal attenuation and maintaining communication despite obstacles, enabling higher data rates and efficient RIS selection.
Implementation Method 1
The BS may transmit downlink (DL) signals to the UE device via reflection off a DL RIS from the set of RIS's
Data Source
AI summary
A communication system may include a base station (BS), user equipment (UE), and a set of reconfigurable intelligent surfaces (RIS's). The RIS's, the UE, and the BS may communicate using a control RAT and a data RAT. The BS may transmit downlink (DL) signals to the UE device via reflection off a DL RIS. The UE device may transmit uplink (UL) signals to the BS via reflection off a UL RIS. This may optimize wireless performance in situations where reflecting the UL and DL signals off the same RIS would limit performance under the current data RAT channel conditions. The BS and the UE device may use channel measurements of the control RAT at the RIS's to select the UL RIS and the DL RIS. This may significantly reduce overhead required to identify the UL and DL RIS's relative to scenarios where exhaustive beam training is used.