Questions tagged [radar]
Anything related to RADAR (RAdio Detection And Ranging) systems and radar signal processing.
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Ambiguity function information
For a course that i'm taking im asked a question about the ambiguity function of a FMCW radar. However i have not found a good source for reading about this so don't quite understand it.
I get given ...
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Conditions for FMCW signal reconstruction using Hilbert Transform
I have an In-phase signal collected by an FMCW radar. I am trying to reconstruct the analytical signal by applying the Hilbert Transform to the In-phase signal.
Are there certain conditions that need ...
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Is it possible to generate SAR like pictures with a non moving MIMO radar and static scene?
Recently I study radar alot and was wondering if there is a possibility to generate SAR like pictures with MIMO radar.
Under the condition that the MIMO radar is not moving and the scene does not ...
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Using radar IQ data to detect motion
I have a 24GHz motion detector (SMR-333 website, sparse datasheet) that gives I and Q, without signal processing. How can I use these values to detect motion? I only need to detect if a person moves ...
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Time shifting a signal in python
I am currently modeling FMCW (linear FM) and SFCW (stepped FM) chirps in python. For my project, I need to simulate those signals as a transmit chirp and a received one, scattered from point targets ...
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Deconvolution of a ground-penetrating radar signal for further convolution with a desired source signal
I am following the instructions of this paper (https://www.earthdoc.org/content/journals/10.3997/1873-0604.2003015) to process a ground-penetrating radar (GPR) signal (a discrete signal sampled at a ...
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Stepped Frequency Modulated Waveform Continuity issues [duplicate]
I want to generate a stepped frequency modulated waveform (SFMW), similar to a linear frequency modulated chirp.
While approaching this, I wanted to consider the issue that there should be some ...
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Use FFT to compute only part of frequency response
I am working on a project in which I need to calculate the range of a target using an FMCW radar. Dependent on the target's range, I expect various beat frequencies to occur in the data from my ADC. I ...
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Minimal SNR to distinguish LFM target from noise at range doppler output
I am working on a radar signal processing project using MATLAB. I am required to simulate range doppler maps for Linear Frequency-Modulation (LFM) targets (non-fluctuating) in noise at various SNRs (...
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Distance and Velocity estimation from FMCW radar Transceiver (KLD-7 by RFbeam)
Module that I am using is KLD-7 radar Transceiver from RFbeam
I am new to FMCW radar systems and I recently started working on distance and velocity calculations from such a system. Although the ...
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Is the maximum possible bandwidth of a radar system dependent (or related) to its center frequency?
One of the core parameters of any radar system is its center frequency. Another core parameter is its bandwidth, which is the reciprocal of its ranging resolution. I am wondering: Is there some sort ...
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Cramer-Rao Bound for Time Delay given a Chirp Waveform with AWGN
In multiple sources (e.g. Richards, Mark A. "Fundamentals of Radar Signal Processing, Second Edition"), I come across the following expression for the CRLB for the time-delay parameter, ...
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Azimuth image extent in frequency domain SAR algorithms (RDA, omega-k)
When looking at the practical implementation of frequency domain SAR imaging algorithms like the range Doppler algorithm (RDA) and the omega-k algorithm (also called range migration algorithm, RMA) as ...
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How to calculate SNR with White gaussian noise
Im working on a Pulsed Doppler Radar
What is the way to calculate the SNR (with WGN)? What will be the lowest SNR for detectability?
Im using matched-filter(xcorr) to process the signal+noise.
My ...
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Doppler Map for a beginner pulsed radar
I have been assigned to simulate a Pulsed radar with Chirps hitting a moving target and then analyzing the data to create a Doppler-Range map.
Im having trouble completing some of the "algorithm'...
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Range-Time Radar Data Processing
I am learning to how it is working this data processing. But I am little bit a confused. There are different ways to obtain this range-time table.
As you can see the picture, obtaining the range-fft ...
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Doppler radar: phase shift sign convention
In my reading about Doppler radar principles, both of the sources I've been using have made a peculiar choice of sign convention: the phase shift of the received pulse relative to the transmitted ...
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Estimating the Most Likely Harmonic Signal in a Spectrogram
Experimental data description: below image is from spectrogram of doppler radar return as I walk toward sensor. Bright sinusoid shape modulated with frequency F is from motion of small retroreflector ...
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FMCW radar IQ data constellation
I am trying to replicate the basic method of vital signal detection based on FMCW radars I found in classical literature on the subject. The issue I am facing at the moment is that of IQ data DC ...
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Deriving the IF phase equation of FMCW
My understanding of the FMCW was limited to one chirp and was mostly focused on frequency analysis. (Mostly built upon this answer)
I wanted to expand my understanding to multiple chirps and was ...
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Phase Unwrapping [duplicate]
I'm also quite new to world of radar signal processing. I don't understand why we have to make phase unwrapping process. Could you light in me about it? It would be nice conversation speak about it.
I ...
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Range-Doppler Coupling in FMCW
I did some derivation of the IF signal of the FMCW using sawtooth LFM.
A chirp with sawtooth LFM is expressed like below
$$x_T (t)=\cos\left(2\pi f_c t + \frac{\pi}{T}B (t-mT)^2 \right)$$
Where, $f_c$ ...
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FMCW chirp data acquisition
I am trying to understand the full mathematics behind FMCW. Using linear-frequency chirp $x(t)$ that has center frequency $f_c$, bandwidth $\Delta f$, duration $T_r$, and amplitude $A$, the ...
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How to convert slant to ground plane SAR image
I have simulated a SAR image using Range Migration Algorithm. Since SAR images are captured in the Slant plane (LOS). I was hoping to convert the slant plane image to a ground plane image. I do ...
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Bandwidth for Noise Calcuation FMCW Radar
I am trying to determine the thermal noise for a Frequency modulated continuous wave radar. The radar is the TI IWR6843 chip. Currently, I am using the radar to transmit a chirp with a bandwidth of 4 ...
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Range Migration Algorithm of Dechirpped signal
"In the dechirped SAR signal range spatial frequency is RF frequency scaled by $\frac{4\pi}{c} $. This quantity is has units of radians per unit length and is denoted by the symbol $K_R$. It ...
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FMCW Range-doppler map
I am trying to form a range-doppler map using dechirped signals. I wanted know if there are any resources that provide and explain the steps taken to form the range-doppler map.
If there are or you ...
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How do I do a point response FMCW SAR simulation?
I am trying to simulate and focus the point response for an FMCW stripmap SAR system. I have specified my target coordinates as
targets = [100,100,0;400,100,0] and ...
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Wrapped phase and phase unwrapping in vital sign detection
I am quite new to the world of radar signal processing and there is this issue that I can't figure out for the life of me.
In Remote Monitoring of Human Vital Signs Using mm-Wave FMCW Radar (Section ...
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Extended omega-k algorithm implementation
I am trying to implement omega-k algorithm with two step motion compensation.
I have read the article: A. Moreira "Extended wavenumber-domain synthetic aperture radar focusing with integrated ...
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Phase Unwrapping Issue of IQ data sample in Radar Signal Processing
I am doing radar Sensor signal processing.
The radar sensor gives iq data corresponding to the range(sweeps)
I want to detect micro motion so that phas analysis is used.
Sweep is the distance ...
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Rayleigh Bandwidth Calculation-Radar
I am trying to generate a simple Gaussian pulse that has a 1 ns pulse width. However, when I generate the pulse, I realized that I did not meet the condition that calculates Rayleigh Bandwidth (1/...
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Answered-Question About Radar Pulse Modulation
I am trying to simulate a radar-transmitted signal with a 4.5 Hz clock frequency and 1.8 GHz carrier frequency. I generated the carrier signal and a rectangle shape pulse signal, then multiplied in ...
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3D-FFT to calculate the AoA in FMCW radar
I am trying to implement 3D-FFT on an IF signal to estimate range-velocity-angle. I was able to get the required results in range and doppler steps. However, when I am doing the angle FFT along the ...
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Clutter Signal and Target Echo
In passive bi-static radar systems, some researchers consider that the clutter and the target echo are mutually independent. So, they use independent component analysis for clutter suppression/...
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How do I generate the approximate Fourier Transform of the signal using Principle of Stationary Phase?
The following excerpt is taken from the textbook "Digital Processing of Synthetic Aperture Radar" by Ian G. Cumming
The Principle of Stationary Phase (POSP) can be briefly explained as ...
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SNR ratio in radar for stationary targets
Is there a mathematical model which provides relationship between the Signal to Noise Ratio in radar measurements and velocity/range of targets. i.e.
How SNR varies with the speed of targets?
How SNR ...
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FMCW radar and calculating ADC Sampling rate
I am new to FMCW radar and I am using a TI module. I have been reading the TI reference material and they keep mentioning the parameter "ADC Sampling Rate". I am confused by what this means ...
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How best to detect an unknown number of pulses of an approximate known form over an interval?
It is approximately 30 years since I last studied signal processing, but have lately encountered a problem for which I am confident the solution is well-known in the signal-processing world. I hope ...
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Noise impact on X-band signal amplification
I have a locally generated 10 GHz LO signal that should go into the LO port of a mixer. The LO signal strength is -1.7 dBm. The mixer has a required LO-drive of about 13 dBm. Before the LO signal hits ...
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FMCW Transmit Signal and Fly-back Effect
I am studying a thesis about nonlinearities in the transmit signal and it mentions the following:
The first 2,500 samples, which correspond to the Tmax of each of each
sweep period and are affected ...
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How to estimate Range, Doppler and Angle with FMCW MIMO Radar?
I am trying to obtain the range, Doppler and angle of arrival estimation with an TDM MIMO FMCW radar.
Actually, I have completed this process. In doing so, however, a few things remained unclear. ...
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How to apply MUSIC to FMCW radar IF data?
I'm working on target extraction with raw FMCW ADC data. I arranged my received data in an (numADCsamples x numAntennas x numChirpsPerFrame) radar cube.
So far I am using range FFT and doppler FFT to ...
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In radar pulse analysis, why is the PRF of pulse not calculated using Fourier transform?
So, I am fairly new to this, but when going through books on Radar pulses, I noticed that quite often, a formula describing the frequency of the waveform is given. For example, the frequency of a ...
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How to eliminate a cyclic spectrum estimation window artifact?
I am using an implementation of the averaged cyclic periodogram (section 3.2.4 in Antoni, Jérôme. "Cyclic spectral analysis in practice." Mechanical Systems and Signal Processing 21.2 (2007):...
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Cross Ambiguity Function Peak Width
I am trying to plot the Cross Ambiguity Function of two OFDM signal (1024 subcarriers) reflected from two targets, which are separated by 30m.
The problem I am facing that the CAF peak width at the ...
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FMCW Radar Doppler Ambiguity related to Nyquist theorem or exceeding the distance frequency or both
I have been reading about doppler ambiguity and I have two explanations for its occurrence that I can't relate to each other.
1st Explanation: In the stationary case (radar and target are stationary) ...
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DSP based phase shifting in Phased Array systems
Is there a downside to doing phase shifting at basedband in the DSP section of phased Array systems?
I suppose you trade off analog components for digital which may be more costly but I suspect modern ...
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SNR estimation from a radar sensor signal
I am using a radar sensor for human activity monitoring which works on 3.18GHz. The received signal by the receiver of the sensor depends on the movements in its area of observation. All the activity ...
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FMCW radar: understanding of doppler fft
I am using fmcw radar to find out distance and speed of moving objects using stm32l476 microcontroller.
I transmit the modulation signal as sawtooth waveform and I read the recieved signal in the ...
