MIMO Transmission Phase Adjustment for LOS Reception Quality

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing communication systems in line of sight (LOS) environments face challenges in achieving high data reception quality due to the dominance of direct waves, which can lead to reduced reception quality in reception devices.

Innovation Solution

A transmission device is designed to improve data reception quality by employing a precoding process, phase changes, and pilot signal insertion. The device generates precoded signals, applies phase changes, and inserts pilot signals to enhance signal processing and reception quality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If MIMO communication method is used in LOS environment, then data transmission capacity is improved, but reception quality deteriorates due to direct wave dominance

Engineering Contradiction:

Improvedata transmission capacityVSAvoidreception quality

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent applies preliminary action by performing precoding processing on transmission signals before transmission. The precoding process modifies the signals in advance to counteract the adverse effects of direct wave dominance in LOS environments, thereby improving reception quality while maintaining MIMO capacity

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent changes parameters by applying different phase changes to different streams and inserting pilot signals at specific positions. These parameter modifications enable the reception device to accurately estimate channel characteristics despite direct wave interference, resolving the contradiction between capacity and reception quality

Inventive Principle:

Principle #35Parameter changes

2Reliability

If phase change is applied to precoded signal, then reception quality is improved, but signal processing complexity increases

Engineering Contradiction:

Improvereception qualityVSAvoidsignal processing complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the phase change operation into different stages: first applying phase change to the precoded signal, then inserting pilot signals. This segmentation allows the reception device to process each stage separately, managing complexity while improving reception quality

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent introduces pilot signals as intermediaries between the phase-changed precoded signal and the channel estimation process. These pilot signals facilitate accurate channel estimation without requiring complex direct processing of the entire signal stream

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS20250070833A1Transmission method, transmission device, reception method, and reception device

Publication Date: 2025.02.27 PANASONIC INTELLECTUAL PROPERTY CORP OF AMERICA

AI summary

A transmission method includes generating a first precoded signal and a second precoded signal by performing a precoding process on a first baseband signal and a second baseband signal, outputting a third signal by inserting a pilot signal into the first precoded signal, outputting a fourth signal by applying a first phase change to the second precoded signal, outputting a fifth signal by inserting a pilot signal into the fourth signal, and outputting a sixth signal by applying a second phase change to the fifth signal.