Interleaved Radar Transmitting Parallel Receiving Phase Offset Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing radar systems for driver assistance face challenges in achieving high accuracy and resolution for angle formation, particularly when dealing with relative speed-dependent phase offsets, especially in interleaved serial transmitting and parallel receiving configurations, which can lead to reduced sensor sensitivity and angle errors.
Innovation Solution
A radar system with 2 transmitting antennas and 4 receiving antennas, where the transmitting antennas operate alternately using frequency ramps, and the receiving signals are processed in parallel, allowing for the separation of phase offsets through Discrete Fourier Transforms (DFTs) and phase corrections, enabling accurate digital beam formation and enhanced sensor sensitivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If interleaved serial transmitting and parallel receiving is used, then hardware outlay is reduced, but sensor sensitivity decreases
Solution Approach 1:
The transmitting function is segmented to operate serially on one antenna at a time, while receiving operates in parallel on multiple antennas simultaneously. This segmentation allows reduced hardware complexity for transmission while maintaining high sensitivity through parallel receiving channels.
Solution Approach 2:
The transmitting antenna operates periodically, alternating between different transmitting antennas in an interleaved manner. This periodic transmission pattern enables the system to maintain sensor sensitivity by ensuring that receiving antennas continuously operate while transmission occurs in periodic intervals across multiple antennas.
2Measurement precision
If multiple transmitting and receiving antennas are used for digital beam formation, then angle formation accuracy improves, but hardware outlay increases
Solution Approach 1:
The antenna system is segmented into multiple transmitting and receiving channels that operate in an interleaved manner. By using the product of transmitting and receiving antenna numbers to form antenna channels, the system achieves high angle formation accuracy through multiple virtual channels without requiring proportionally more physical hardware.
Solution Approach 2:
The system dynamically alternates between different transmitting antennas while maintaining continuous parallel receiving operation. This dynamic switching creates multiple antenna channels over time, achieving the same angle formation capability as having all antennas simultaneously active, but with reduced hardware requirements.
3Device complexity
If transmitting antennas operate alternately, then hardware outlay is reduced, but phase offsets occur due to temporal offsets
Solution Approach 1:
The system measures the relative speed of objects using the Doppler effect and uses this feedback to calculate and compensate for phase offsets in the digital beam formation process. By continuously adjusting for temporal offsets based on measured relative speed, the system eliminates angle errors while maintaining the simplified interleaved operating mode.
Solution Approach 2:
The system changes the operational parameters of the transmitting antennas, alternating between different antennas in an interleaved sequence. This parameter change in transmission timing is compensated by adjusting the digital beam formation calculations to account for the known temporal offsets, thereby maintaining measurement accuracy despite the simplified hardware operation.
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 configuration achieves the maximum number of antenna channels, ensuring optimal accuracy and resolution for angle formation, even with weak objects and multiple equally rapid objects, without increasing hardware complexity, and maintains sensitivity by compensating for relative speed-related phase offsets.
Implementation Method 1
radar sensors are mainly used for driver assistance systems of the type described above
Implementation Method 2
can measure, in addition to the distance of objects, their radial relative speed directly as well via the Doppler effect
Data Source
AI summary
An environmental detection method for a vehicle uses transmitting antennas to emit transmission signals that each consist of a sequence of identical or similar single signals, uses receiving antennas to receive the transmission signals reflected from objects, and processes the received signals. The transmission signals are emitted from only one transmitting antenna at a time, and the active transmitting antenna alternates cyclically from single signal to signal. All receiving antennas are always used in parallel. The received single signals are accumulated in proper phase for the different combinations of transmitting and receiving antennas to at least one relative speed hypothesis of objects. Digital beam formation is performed based on the accumulated signal values, each belonging to the same relative speed hypothesis, from different antenna combinations. Phase differences between received signals from different transmitting antennas are thereby taken into consideration.