Terminal CSI Feedback Segmentation for Vertical Beamforming
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, existing technologies face challenges in efficiently transmitting CSI feedback information, particularly in coordinating beamforming between terminals and base stations, due to differences in coherence times and the need for separate encoding of rank indication, channel quality information, and precoding matrix indicators.
Innovation Solution
A terminal is designed to generate and transmit CSI feedback information, including rank indication, beam index, wideband channel quality indicators, and precoding matrix indicators, using a processor and radio frequency unit to manage the transmission of these components across multiple subframes, employing techniques such as joint encoding and matrix multiplication to efficiently convey beamforming information to the base station.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If CSI feedback information (RI, CQI, PMI) is transmitted separately at different periods, then measurement precision is improved, but loss of time increases due to multiple transmission periods
Solution Approach 1:
The patent combines RI, CQI, and PMI into a single joint feedback transmission. The terminal generates a unified CSI report containing all three components and transmits them together in one uplink subframe, eliminating the need for separate transmissions at different periods while maintaining the accuracy benefits of independent measurement.
2Adaptability or versatility
If the terminal transmits beam index and RI in the first feedback subframe, then adaptability is improved for vertical beamforming, but device complexity increases due to separate encoding requirements
Solution Approach 1:
The patent segments the CSI feedback into two parts: (1) beam index and RI transmitted in the first feedback subframe to enable vertical beamforming, and (2) CQI and PMI transmitted in the second feedback subframe. This segmentation allows the base station to perform vertical beamforming with the beam index while keeping encoding complexity manageable through structured separation.
3Reliability
If the payload size is limited to secure uplink coverage, then reliability is improved, but loss of information increases due to truncated feedback
Solution Approach 1:
The patent divides the complete CSI feedback into two segments transmitted in different uplink subframes. The first subframe carries beam index and RI with smaller payload to ensure coverage, while the second subframe carries CQI and PMI. This segmentation ensures that each transmission stays within payload limits for reliable delivery while collectively conveying the complete CSI information.
Solution Approach 2:
The patent transmits the most critical feedback information (beam index and RI) in the first subframe before transmitting the remaining information (CQI and PMI) in the second subframe. This preliminary action ensures that the base station receives essential beamforming parameters first, enabling it to establish reliable uplink coverage while progressively receiving complete feedback information.
Data Source
AI summary
Disclosed herein is a terminal including: receiving a CSI-RS from a base station, generating CSI feedback information including indicators such as RI, PTI, and BI and a first PMI and a second PMI that are elements of a double codebook, on the basis of the CSI-RS and transmits the CSI feedback information to the base station through an uplink subframe corresponding to predetermined feedback periodicity.