Uplink Data Symbols for Active User Detection in 5G
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current 5G wireless communication systems face challenges in efficiently performing active user detection and channel estimation, particularly in grant-free transmission methods, where the high probability of preamble collisions and increased overhead in control signals hinder data transmission, especially in massive machine-type communication scenarios.
Innovation Solution
The proposed solution involves using different codebooks for data symbols and reference signals, allowing terminals to map codes onto data symbols and transmit them for base stations to detect active users and estimate channels independently or jointly, enhancing the performance of active user detection and channel estimation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If grant-free transmission method is used for uplink data transmission, then transmission speed is improved, but active user detection accuracy deteriorates due to preamble collisions
Solution Approach 1:
The patent segments the detection process into two independent stages: first detecting active users using data symbols, then estimating channels using reference signals. This segmentation allows each stage to focus on its specific function, improving overall detection accuracy while maintaining the grant-free transmission speed benefits.
Solution Approach 2:
The patent introduces data symbols as an intermediary carrier that embeds user identification information. Instead of relying solely on preambles for user detection, the data symbols serve as a mediator that enables both user detection and channel estimation, resolving the collision issue while maintaining transmission speed.
2Difficulty of detecting and measuring
If control signals are used for active user detection and channel estimation, then detection capability is provided, but overhead increases
Solution Approach 1:
The patent makes data symbols serve multiple functions: they carry user identification information for active user detection and also serve as carriers for channel estimation when combined with reference signals. This multi-functionality eliminates the need for separate dedicated control signals, reducing overhead while maintaining detection capability.
Solution Approach 2:
The patent changes the parameter usage by embedding detection information within data symbols rather than using separate control signals. This parameter change allows the same signal resources to serve both detection and communication functions, reducing the quantity of overhead signals required.
3Measurement precision
If separate codebooks are used for data symbols and reference signals, then detection and estimation performance is improved, but device complexity increases
Solution Approach 1:
The patent segments the codebook functionality into separate sets for data symbols and reference signals, allowing optimized code selection for each purpose. This segmentation improves detection and estimation performance by enabling specialized codebooks for each function while maintaining manageable complexity through structured organization.
Data Source
AI summary
The present disclosure relates to a 5G or pre-5G communication system for supporting a higher data transmission rate than in a 4G communication system such as LTE. The present disclosure relates to uplink transmission in a wireless communication system, and an operating method of a terminal includes mapping codes that are included in at least one codebook onto data symbols. and transmitting the data symbols spread by using the at least one codebook, and the data symbols are used for a base station to detect at least one active terminal including the terminal.