Uplink Rank 3 Codebook Optimization for PAPR Reduction

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Solution Overview

Problem

MIMO technology faces challenges in effectively applying its benefits to uplink signal transmission due to issues like Peak Power to Average Power Ratio (PAPR) and Cubic Metric (CM) characteristics, which are deteriorated when MIMO schemes are extended to uplink signals, necessitating a new approach for optimizing codebooks and precoding matrices.

Innovation Solution

A method and system for uplink signal transmission using an optimized rank 3 codebook with specific precoding matrices, including Discrete Fourier Transform (DFT) spreading and Single Carrier - Frequency Division Multiple Access (SC-FDMA) symbol construction, to manage PAPR and CM properties, employing a prestored codebook with 12 precoding matrices to enhance transmission efficiency across four antennas.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If MIMO schemes are extended to uplink signals, then data transmission rate and system capacity are improved, but PAPR and CM characteristics are deteriorated

Engineering Contradiction:

Improvedata transmission rateVSAvoidPAPR and CM characteristics

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent applies parameter changes by modifying the codebook structure and precoding matrix parameters specifically for uplink MIMO transmission. An optimized rank 3 codebook with 12 precoding matrices is designed to adjust the transmission parameters, achieving better PAPR and CM characteristics while maintaining high data transmission rates in uplink signals.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If an optimized rank 3 codebook with 12 precoding matrices is used, then transmission efficiency and reliability are improved, but signaling overhead increases

Engineering Contradiction:

Improvetransmission reliabilityVSAvoidsignaling overhead

Core Design Contradiction:

ReliabilityVSLoss of information

Solution Approach 1:

The patent applies partial action by selectively using a rank 3 codebook with 12 precoding matrices only when uplink transmission conditions require optimized performance. This partial deployment approach improves transmission reliability for specific uplink scenarios while minimizing overall signaling overhead by not applying the full codebook optimization universally across all transmission conditions.

Inventive Principle:

Principle #16Partial or excessive action

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

The solution enables efficient uplink signal transmission by optimizing PAPR and CM properties, effectively addressing the challenges of MIMO application in uplink signals, thereby improving transmission rate and reliability while minimizing signaling overhead.

Implementation Method 1

performing Discrete Fourier Transform (DFT) spreading upon each of signals of the three layers

Methodology Applied

Scientific EffectDiscrete Fourier Transform:

Data Source

PatentEP2420006B1Uplink signal transmission and reception using optimized rank 3 codebook

Publication Date: 2018.05.30 LG ELECTRONICS INC

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AI summary

A method for transmitting and receiving uplink signals using an optimized rank 3 codebook is disclosed. The optimized rank 3 codebook includes 6 precoding matrix groups, each of which has 1 variable having an amplitude of 1. Preferably, the optimized 4Tx rank 3 codebook has 12 precoding matrix, two precoding matrixes are selected from each the above 6 precoding matrix groups considering chordal distance and the number of precoding matrix.