DM-RS Configuration for Open-Loop Multi-Antenna Transmission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems, such as LTE, face challenges in efficiently configuring reference signals for open-loop multi-antenna transmission, which affects data transmission diversity and multiplexing schemes, leading to suboptimal performance in terms of data transmission rate and channel estimation accuracy.
Innovation Solution
The method involves receiving and transmitting downlink channels using DM-RS (demodulation reference signal) configuration information, where single-codeword transmission employs SFBC-based transmission diversity on antenna ports 7 and 8, and two-codeword transmission uses co-phase cycling-based spatial multiplexing on the same ports, allowing for efficient feedback reporting and improved channel state information reporting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If DM-RS configuration information is used to indicate transmission schemes, then data transmission efficiency is improved, but device complexity increases due to additional configuration management
Solution Approach 1:
The patent changes the parameter representation by using DM-RS configuration information fields to indicate transmission schemes. Instead of separate signaling for transmission mode and reference signal configuration, the invention encodes multiple parameters (transmission scheme type, antenna port, scrambling identity) into unified DM-RS configuration fields, reducing signaling overhead while maintaining flexibility in transmission scheme selection
Solution Approach 2:
The DM-RS configuration information serves multiple functions simultaneously: it configures the demodulation reference signal parameters, indicates the transmission scheme type (transmission diversity or spatial multiplexing), and provides antenna port and scrambling identity information. This multi-functionality reduces the need for separate signaling mechanisms and simplifies overall configuration management
2Reliability
If transmission diversity scheme is used for single-codeword transmission, then reliability is improved, but data transmission rate decreases due to conservative transmission approach
Solution Approach 1:
The patent implements dynamic selection between transmission diversity scheme and spatial multiplexing scheme based on channel conditions and transmission requirements. The DM-RS configuration information dynamically indicates which scheme to use, allowing the system to adapt between reliability-oriented transmission diversity and rate-oriented spatial multiplexing, optimizing the trade-off between reliability and data transmission rate for each transmission instance
3Productivity
If spatial multiplexing scheme is used for two-codeword transmission, then data transmission rate is improved, but channel estimation accuracy deteriorates due to increased interference
Solution Approach 1:
The patent uses DM-RS (demodulation reference signal) as an intermediary to improve channel estimation accuracy in spatial multiplexing mode. The DM-RS configuration information specifies dedicated reference signals for each antenna port, allowing the receiver to estimate channel responses for multiple spatial layers independently. This intermediary reference signal mechanism enables accurate channel estimation even when multiple codewords are transmitted simultaneously through spatial multiplexing
4Productivity
If DM-RS configuration information is included in downlink control channel, then feedback reporting efficiency is improved, but downlink control channel overhead increases
Solution Approach 1:
The patent merges transmission scheme indication information with DM-RS configuration information in the downlink control channel. Instead of separate signaling for transmission mode and reference signal parameters, the invention combines these into unified DM-RS configuration fields, reducing the total number of bits required for control signaling while enabling efficient feedback reporting based on the configured transmission scheme
Data Source
AI summary
A method of receiving a downlink channel, which is received by a user equipment from an eNB in a wireless communication system, is disclosed in the present specification. Specifically, the method includes the steps of receiving a downlink control channel for receiving a DM-RS (demodulation reference signal) based downlink data channel from the eNB, and receiving the DM-RS based downlink data channel using DM-RS configuration information included in the downlink control channel. In this case, if single-codeword transmission via the DM-RS based downlink data channel is indicated by the downlink control channel, the DM-RS based downlink data channel is received using a transmission diversity scheme. If two-codewords transmission via the DM-RS based downlink data channel is indicated by the downlink control channel, the DM-RS based downlink data channel is received using a spatial multiplexing scheme.