FMCW Radar Pulse Sequencing for Range Resolution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional radar systems in advanced driver assistance systems (ADAS) and automated driving systems (ADS) suffer from marginal range resolution and are susceptible to interference from environmental sources, leading to false sensing and potential system failure.
Innovation Solution
A radar system employing a sequence of frequency-modulated continuous-wave (FMCW) pulses, where multiple transmit and receive antennas generate data sets that are analyzed using Fast Fourier Transform (FFT) to improve range resolution and noise immunity without increasing bandwidth or cost.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional radar transceivers use limited bandwidth signals, then system cost is reduced, but range resolution deteriorates
Solution Approach 1:
The patent employs periodic FMCW pulses transmitted in sequences, where each pulse undergoes frequency modulation over time. By transmitting multiple periodic pulses and processing them collectively through FFT, the system achieves enhanced range resolution without requiring continuously wide bandwidth signals, thus resolving the contradiction between measurement precision and device complexity
Solution Approach 2:
The patent changes the temporal and spectral parameters of the transmitted signal by using frequency-modulated continuous wave pulses with specific chirp rates and pulse repetition intervals. This parameter optimization allows the system to achieve better range resolution through signal processing of multiple pulses rather than relying solely on instantaneous bandwidth, addressing the contradiction between measurement precision and device complexity
2Measurement precision
If radar systems increase bandwidth to improve range resolution, then measurement precision is improved, but system cost increases
Solution Approach 1:
By using periodic FMCW pulses transmitted in sequences and processing multiple pulses through FFT, the system achieves enhanced range resolution equivalent to wider bandwidth signals without actually transmitting wider bandwidth signals. This approach improves measurement precision while avoiding the increased system cost that would result from hardware designed for wider bandwidth operation
Solution Approach 2:
The patent uses multiple partial pulses, each with moderate bandwidth, transmitted in sequence. The collective processing of these partial actions (multiple pulses) achieves the effect of a single excessive-action wideband pulse, thereby improving range resolution without the prohibitive system cost associated with true wideband radar transceivers
3Reliability
If radar systems use single pulse transmission, then device complexity is reduced, but reliability deteriorates due to interference susceptibility
Solution Approach 1:
The patent transmits periodic FMCW pulses in sequences rather than single pulses. By processing multiple periodic pulses through FFT, the system achieves frequency domain separation that enhances interference resistance. The periodic structure allows coherent integration of desired signals while incoherent accumulation of interference, thereby improving reliability without excessive increase in device complexity
Solution Approach 2:
The system uses the information from multiple transmitted and received pulses to perform FFT analysis, effectively using past pulse information to improve current target detection reliability. This feedback mechanism through sequential pulse processing enhances interference resistance by allowing the system to distinguish between coherent target returns and random interference
4Measurement precision
If radar systems transmit multiple FMCW pulses in sequence, then range resolution is improved, but loss of time increases
Solution Approach 1:
The patent uses efficiently designed periodic FMCW pulse sequences where each pulse is transmitted and received within a optimized time window. By carefully selecting pulse repetition intervals and chirp durations, the system achieves enhanced range resolution through multiple pulses while minimizing the total time loss. The periodic structure allows for efficient time-frequency analysis that recovers information faster than non-periodic approaches
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 proposed system enhances range resolution and resistance to interference, providing accurate target detection and reducing false alarms, thereby improving the reliability of ADAS and ADS systems.
Implementation Method 1
a receive antenna arranged to generate first data in response to receiving a first reflected signal corresponding to the first FMCW pulse and to generate second data in response to receiving a second reflected signal corresponding to the second FMCW pulse
Data Source
AI summary
A radar system includes a transmit antenna arranged to transmit a first frequency-modulated continuous-wave (FMCW) pulse and a second FMCW pulse, wherein the second FMCW pulse is subsequent to the first FMCW pulse. A receive antenna is arranged to (1) generate first data in response to receiving a first reflected signal corresponding to the first FMCW pulse, and (2) generate second data in response to receiving a second reflected signal corresponding to the second FMCW pulse. A processor is configured to perform a Fast Fourier Transform (FFT) analysis of the first data and the second data after receiving the first data and the second data.