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### Motion compensation for stripmap SAR

I am trying to perform motion compensation for an airborne stripmap SAR data following the book Synthetic Aperture Radar Processing by Franceschetti and Lanari. The algorithm flowchart is on page 145. ...
664 views

### Range Compression

How exactly is the SAR image resolution increased by the linear frequency modulation of the transmitted signal and further by the compression of range and azimuth?
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### 3D model from high speed videos?

Is there a way to convert or somewhat replicate RADAR data from a set of given high speed videos taken from multiple angles. The problem is quite ill defined but the task I have in hand is to ...
501 views

### How to perform dechirping of SAR image in MATLAB?

I have the transmitted pulse and the raw SAR image before range compression (dechirping). I understand the pulse compression its a convolution along the columns but I am not able to make it work. I've ...
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1 vote
1k views

### Synthetic Aperture Radar (SAR). How to do Range Compression?

I am trying to perform range compression to a raw SAR image [fast times, sensor position], Dr in code. I have the transmitted signal (chirp), g in code, and literature says range compression is ...
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72 views

### modelling radar system for image generation

I am trying to find or derive some model for radar using python and blender which should hopefully create a simulation of what a radar image of the blender environment would look like. I have been ...
2k views

### Radar signal processing flow chart

I'm new to Radar in general, and I'm studying RADAR using online resources. I came across the following slide which shows the process flow of the Radar signal processing. The thing I don't get in ...
298 views

### Pulse Doppler Radar: time delay in down conversion

My understanding of Pulse Doppler Radar is the system measures Time Of Flight for the pulse. My confusion is that during the down conversion process prior to ADC the lowpass filter causes some time ...
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323 views

How can we justify doing coherent radar when the phase of the return is unknown? For instance, after a reflection, assuming a stationary target, we should get something akin to: $$x_{rx}(t) = |\... • 129 2 votes 1 answer 176 views ### Minimizing Time Sidelobes with Pulse Compression I am trying to compute a compression filter function to minimize the error from a a desired pulse compression result. The usual approach to doing this is to minimize the RMS error of the the ... • 265 3 votes 1 answer 260 views ### FFT strong signal in middle frequency bin I've developed a radar that I'm using to determine the distance to remote objects. It uses a custom PCB with an onboard FPGA that performs the DSP algorithms. The data from it is then plotted on a ... • 239 0 votes 0 answers 152 views ### Range Migration Algorithm in FMCW MIMO RADAR I’m using a FMCW MIMO radar [77-79 GHz] with a virtual linear array made of 48 channels. I’m wondering if the adaptation of the range migration algorithm (typically used in SAR processing) is ... • 125 1 vote 0 answers 128 views ### Root MUSIC and solution of conjugate palindromic polynomials The root-MUSIC algorithm gives direction of arrival angles directly and avoids the computational overhead of computing the MUSIC estimator curve (see Direction of Arrival Estimation using a Root-MUSIC ... 0 votes 1 answer 69 views ### How is ESPRIT pronounced? I'm implementing high resolution DOA algorithms including ESPRIT for radar systems. The word ESPRIT is obviously an acronym but, even so, how is it pronounced? Is the second i long like "ESPREEE" as ... 3 votes 1 answer 371 views ### Combining two Images with Different Resolutions into Higher Resolution Image I am attempting to combine two radar images, each of which is a 3-dimensional cube with a range dimension, an azimuth angle dimension, and an elevation angle dimension. One image has high azimuth ... 1 vote 2 answers 537 views ### Doppler Shift and the Pulse Repetition Interval Suppose that I have a signal x(t) consisting of N pulses at a given frequency \omega_{c}. I space them T seconds apart, ie the Pulse Repetition Interval (PRI) for the waveform is T. Now ... • 632 0 votes 1 answer 930 views ### Advantages and disadvantages in term of radar performance of LFM chirp Which are the advantages and disadvantages of a LFM chirp regarding its radar performance? • 182 1 vote 2 answers 92 views ### Matched Filters for attenuation detection? I have been reading about matched filters and I'm interested in possible uses for them, I have seen they are used very often in radar, in such a way that you send out a signal, and then you read the ... 0 votes 1 answer 83 views ### Why the ideal ambiguity function (AF) for radar has the maximum in (0, 0) and zero otherwise? I was wondering why is the ideal AF has zero value in all the function except in (0, 0). • 182 0 votes 0 answers 106 views ### RRC filter or rectangular pulse shaping filter in LFM chirp signal I am working with a LFM up chirp signal, and I wanted to embed some data on it using a BPSK constellation. My doubt was, ¿should I use a RRC filter, like in usual communications schemes, or should I ... • 182 0 votes 1 answer 764 views ### Question about FMCW range-velocity plot I am working on plotting range-velocity heatmap of the receiving FMCW signal. I actually have already plotted. However, I do not really understand the mapping relationship between Doppler FFT bin and ... 0 votes 1 answer 971 views ### Real signal from I,Q, sample rate and center frequency I am given a recording of an ionosonde sounding. The signal S is represented as a series of I/Q pairs at a sample rate F_{sr} = 10\,\text{MHz}. I am told that the center frequency of the ... • 135 0 votes 1 answer 2k views ### Baseband representation of a LFM chirp signal I need to generate a chirp signal between f_{start} = -f_{limit} and f_{stop} = f_{limit}, to compare it to a FrFT generated signal. The FrFT signal of order \alpha = 0 is PAM modulated data ... • 182 1 vote 2 answers 2k views ### Omega-K algorithm implementation for synthetic aperture radar I have been trying to develop Omega-k algorithm for SAR image formation. I am using the equations from chapter 8 in digital processing of Synthetic Aperture Radar data by Cumming and Wong. The steps I ... 1 vote 0 answers 152 views ### Precision accuracy radar in radar systems how does one measure the precision and accuracy on a radar? I'm confused with differen definitions in the references: Richards define (Principles of Modern Radar: Basic Principles - ... • 155 1 vote 1 answer 301 views ### Carrier frequency of chirp signal I am computing the link budget for a communication-radar (CoRadar) system. The formula for maximum distance, in communication, is: d_{max} = \sqrt{\frac{P_t}{\tau}\frac{G_t G_{r, comm} \lambda^2}{(4\... • 182 0 votes 2 answers 281 views ### Why having a ridge like Ambiguity Function implies lack of Doppler resolution? I was wondering why if the AF (Ambiguity Function) has a ridge like form it has low Doppler resolution. • 182 0 votes 1 answer 63 views ### how can I plot a power spectrum for 150 range bins with 512 fft points [closed] This is my code for plotting... However when I plot my spectrum data using this code, it is showing only 1 row. How can I plot all 150 rows? Can anyone help me to solve this? ... 0 votes 1 answer 82 views ### How to classify the movement type of a target into two categories(direct motion or else) by using a doppler radar? How to classify the movement type of a target just into two categories(one is direct motion which is almost straight line movement and the other is anything else) by using a doppler radar with a ... 0 votes 2 answers 3k views ### In case of using a Doppler radar, do we have to use IQ demodulation to find the direction of a target? I want to know the way to find the velocity of a target by using a doppler radar. I read some paper about it, In summary, send rf signal to a target receive the reflected signal from the target. ... 0 votes 1 answer 263 views ### References ISAR - Inverse Synthetic Aperture Radar [closed] Anybody know a reference to start understanding ISAR? Book or article. Thanks! • 155 1 vote 1 answer 295 views ### Light Detection and Ranging (LIDAR) Range Bias Compensation with Light Dependent Resistor (LDR) I have a distance sensor (VL53L0X), which measures the distance to an object. It is placed outside. I currently do 100 measurements in the best available range mode, then I take the median and insert ... • 113 1 vote 1 answer 494 views ### Doppler Shift of Phase Coded Pulse Compression Waveform Suppose I want to transmit the signal:$$ x(t) = g\Big(\frac{t-t_{0}}{T}\Big) \cdot \cos(2 \pi f_{0} t + \theta_{0}) + g\Big(\frac{t-t_{1}}{T}\Big) \cdot \cos(2 \pi f_{1}t + \theta_{1})  Where $g(... • 632 2 votes 1 answer 3k views ### How to Calculate the Ambiguity Function (Maybe this should be on Stackoverflow instead ...) What is the best way to calculate the ambiguity function? There are different implementations out there for Python (like PyTFTB or from ... 3 votes 2 answers 158 views ### motion compensation for range migration algorithm Is there a simple to follow explanation of how to do second order motion compensation for range migration algorithm? The one described in Carrara et al is for the ideal case. For the Extended Omega K ... • 95 1 vote 1 answer 753 views ### CFAR Detectors and Interference Constant False Alarm Rate (CFAR) is an automatic thresholding technique. It's situated after the FFT processing in other to detect target peak. This probability of detection depends on clutter and ... • 127 1 vote 0 answers 114 views ### Is there a situation when maximizing SNR doesn't also maximize probability of detection? The problem I'm working on is signal detection of a radar signal, but I suspect this problem shows up in many different branches of signal processing. Background: From [1], the factor$I_f$, by ... • 2,222 2 votes 1 answer 881 views ### FMCW Radar Signal Processing Flowchart / Ambiguity Function I Read many papers on signal processing for pulsed and FMCW radars, taking the FMCW type, the signal processing start after mixing the received and transmitted signal, the result of this operation is ... • 127 0 votes 1 answer 426 views ### RADAR Video Signal and Matched Filtering In order to make my question more clear and give more details I'm trying to understand the processing signal procedure in radars,i understood till this moment that a transmitter generates a signal ... • 127 5 votes 2 answers 8k views ### Deriving the Resolution Equation of an FMCW RADAR I am interested in the equation that depicts the resolution of an FMCW radar. I write the same below.$\Delta d = \frac{c}{2b}$First I would like to have an intuitive explanation to the above ... • 223 2 votes 2 answers 170 views ### Compressive Sensing and Sparsity We apply compressive sensing to reconstruct a signal if it is sparse in the original domain or has a sparse represetation in some basis. How we may know a if a signal is sparse or has a sparse ... • 127 3 votes 2 answers 975 views ### DOA - 1D Music Algorithm I am currently working on a MUSIC algorithm for DOA of RF emitters in 3D. At the first stage, interested to apply the 1D MUSIC using a linear array of 4 antennas, and estimate only the azimuth of the ... • 113 0 votes 0 answers 298 views ### Spectrum of received signal from radar fm-cw I obtained actual data from a researcher, consisting of a matrix composed of several received signals from an up-ramp fm-cw radar. Wouldn't be reasonable to plot the spectrogram of a ramp up and ... 0 votes 1 answer 188 views ### azimuth extent for range migration algorithm Is it true that in the Range Migration Algorithm for synthetic aperture radar, the azimuth extent can be said to span the length of the flight path? This makes sense but also does not make sense. ... • 95 0 votes 0 answers 239 views ### How to remove echo/reflected-sound caused by stationary objects when building a ultrasound based radar I am emitting ultrasound with a speaker and am trying to track moving objects with a microphone array by detecting doppler shifts. I have succeeded to detect movement. However, to detect the direction ... 2 votes 1 answer 241 views ### Derivation of range migration algorithm Problem: In Walter G.Carrara's book on synthetic aperture radar, the equation is presented:$\Phi(K_X, K_R) = -K_XX_t - R_B\sqrt(K_R^2 - K_X^2) +K_RR_S \$ (10.30) And this is said to come from ...
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256 views

I would like to know the algorithms to get the angle, range, distance.. so I'm planning to do antenna tracking. What should I do in basic steps to track objects using that module ? what algorithms ...
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### Scan shallow water

I need to scan a shower tray with & without the water running to assess the puddling at the drain, then export a point cloud or surface. Sonar & Laser dont seem to be able to deliver, can ...
565 views

### Designing an efficient curve-matching algorithm

I'm currently designing a curve-matching algorithm and as I already explored many ideas I'm requesting your help. So, if you got some advices about how to handle this problem, feel free to answer! ...
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