Radar Antenna Array Vertical Beam Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Radar apparatuses face challenges in accurately estimating the height of targets, particularly when the target is lower than the radar installation height, due to interference from road reflected waves, leading to incorrect collision determination and reduced accuracy in detecting low targets like curbs or blocks.
Innovation Solution
The radar apparatus employs a configuration with a plurality of receiving antennas and an estimation processing circuit that extracts the angle of arrival and angle spread of reflected waves to accurately estimate target position, using a virtual receiving array to enhance resolution and separate direct and road reflected waves, even when the target is below the radar installation height.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the radar apparatus receives reflected waves using a single receiving antenna or simple array configuration, then the device complexity is reduced, but the measurement precision of target position and height deteriorates due to inability to separate direct and road reflected waves
Solution Approach 1:
The patent segments the received signal into multiple components by using a vertical array of receiving antennas. Each antenna element captures the composite signal containing both direct reflected waves from the target and road reflected waves. Through signal processing, the system separates these components based on their different arrival angles, enabling accurate target height estimation even when the target is below the radar installation height.
Solution Approach 2:
The patent introduces a vertical dimension to the receiving antenna array, arranging multiple antennas vertically rather than horizontally. This vertical arrangement creates a vertical baseline that enables the system to resolve the elevation angle differences between direct and road reflected waves, providing the additional dimensional information needed to separate these signals and accurately determine target position and height.
2Manufacturing precision
If the radar apparatus uses a narrow angle directional beam for scanning, then the manufacturing precision of beam direction is improved, but the productivity of target detection deteriorates due to requiring many scans
Solution Approach 1:
The patent transitions from horizontal beam scanning to vertical beam formation using a vertical array of receiving antennas. Instead of mechanically or electronically scanning the beam horizontally across the field of view, the system forms vertical beams that directly resolve the elevation angle of incoming signals. This dimensional change eliminates the need for time-consuming horizontal scans while maintaining accurate angular resolution.
Solution Approach 2:
The patent replaces mechanical or electronic beam scanning mechanisms with a signal processing approach using a vertical antenna array. Rather than physically or electronically steering a narrow beam through multiple scan positions, the system uses the spatial distribution of signals across the vertical array to directly determine the angle of arrival, substituting mechanical/electronic scanning with a static array measurement system.
3Productivity
If the radar apparatus uses thinning-out scan intervals to reduce scanning time, then the productivity of target tracking is improved, but the measurement precision of angle of arrival deteriorates
Solution Approach 1:
The patent uses a vertical antenna array to measure the angle of arrival in the elevation dimension, which is independent of the horizontal scanning process. This allows the system to obtain accurate angle information even when horizontal scan intervals are thinned out, because the vertical array continuously provides angular resolution without requiring frequent horizontal scans.
Solution Approach 2:
The vertical array of receiving antennas acts as an intermediary that provides continuous angular measurement capability independent of the horizontal scanning rate. By introducing this intermediate measurement system, the patent decouples the tracking speed from the angle measurement precision, allowing fast tracking with thinned scan intervals while maintaining accurate angle of arrival estimation through the vertical array's spatial sampling.
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
This approach allows for precise estimation of target height and width, improving collision determination accuracy even when the vehicle is stopped or the target is on the side, by effectively separating direct and road reflected waves and enhancing the radar's ability to detect low targets.
Implementation Method 1
a radar apparatus including a reception circuit that receives a reflected wave signal which is a radar signal reflected by a target by using a plurality of receiving antennas
Implementation Method 2
estimating the angle of arrival (the direction of arrival) of the reflected waves by using a signal processing algorithm based on the reception phase difference with respect to the element interval (the antenna interval)
Implementation Method 3
the detection circuit detects an angle spread in the first direction around the angle of arrival by using the reflected wave signal of the linear array
Data Source
AI summary
In a position estimation processing unit, by using the reflected wave signal of an array composed of receiving antennas arranged in a first direction among a plurality of receiving antennas, a maximum likelihood value extraction unit extracts the angle of arrival of a reflected wave signal in a first direction. An angle spread detection unit detects the angle spread in the first direction around the angle of arrival by using the reflected wave signal of the array. A target height estimation unit estimates the position of the target in the first direction by using the angle of arrival and the angle spread.