MIMO Radar Bidirectional Angle Measurement for Multipath Distinction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing MIMO radar signal processing devices struggle to accurately distinguish between direct and multipath propagation modes, which affects the accuracy of grasping the propagation environment.

Innovation Solution

A MIMO radar signal processing device that includes a tentative angle measuring unit, a bidirectional angle measuring unit, and a propagation mode distinguishing unit to calculate bidirectional measured angles, allowing for precise differentiation between direct and multipath propagation modes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If only a tentative measured angle value is calculated assuming direct propagation mode, then the calculation process is simple, but the accuracy of distinguishing propagation modes is insufficient

Engineering Contradiction:
Improveaccuracy of propagation mode distinctionVSAvoidcomplexity of angle measurement process
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The angle measurement process is segmented into two distinct parts: a tentative measured angle value calculated under the assumption of direct propagation mode, and a bidirectional measured angle value that considers both direction-of-departure and direction-of-arrival. This segmentation allows the system to maintain a simple initial calculation while adding a more sophisticated measurement only when needed for accurate propagation mode distinction.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention transitions from a single-dimension angle measurement (tentative measured angle assuming direct propagation) to a two-dimension bidirectional measurement (considering both direction-of-departure and direction-of-arrival). This dimensional expansion enables more accurate propagation mode distinction by capturing the asymmetry between transmission and reception paths in multipath scenarios.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Measurement precision

If bidirectional measured angle values are calculated for all reception signals, then propagation mode distinction accuracy is improved, but the processing time and computational load increase

Engineering Contradiction:
Improveaccuracy of propagation mode distinctionVSAvoidsignal processing time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The system applies partial action by calculating the full bidirectional measured angle values only when necessary for accurate propagation mode distinction, rather than for all reception signals uniformly. The tentative measured angle value serves as a quick initial assessment, and bidirectional measurement is applied selectively to resolve ambiguities, thus balancing accuracy with processing efficiency.

Inventive Principle:
Principle #16Partial or excessive action

3Reliability

If the propagation environment is not accurately grasped, then the system operation is simpler, but the reliability of radar detection decreases

Engineering Contradiction:
Improvereliability of radar detectionVSAvoidcomplexity of propagation environment sensing
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention introduces an intermediary propagation mode distinguishing unit that mediates between the angle measurement processes and the radar detection system. This unit uses the bidirectional measured angle values to determine whether direct propagation or multipath propagation is occurring, providing accurate propagation environment information without requiring the entire radar system to be overly complex.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP4369024B1MIMO radar signal processing device and reception signal processing device, and method for distinguishing propagation mode of reception signal vector of interest
Publication Date: 2025.08.27 MITSUBISHI ELECTRIC CORP
  • EP4369024B1 patent drawingFigure 1
  • EP4369024B1 patent drawingFigure 2~3
  • EP4369024B1 patent drawing

AI summary

A MIMO radar signal processing device includes a plurality of matched filter banks (1211 to 121M) to receive reception signals from a plurality of reception antennas (21 to 2M) and transmission signals from a plurality of transmission signal generating units (1111 to 111N), and output matched filter outputs serving as a vector element of a reception signal vector, a tentative angle measuring unit (122) to assume the matched filter outputs from the plurality of matched filter banks (1211 to 121M) as reception signals in a direct propagation mode and calculate a tentative measured angle value for a reception signal vector of interest, and a bidirectional angle measuring unit (123) to obtain a bidirectional measured angle value for the reception signal vector of interest from the matched filter outputs from the plurality of matched filter banks (1211 to 121M) and the tentative measured angle value calculated by the tentative angle measuring unit (122).