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### Is it possible to get the velocity vector for tangential movement using radar?

When an object appears towards the radar sensor or goes away from the radar sensor, there is a change in the phase shift of the frequency and from that, the velocity can be inferred. So, I have two ...
2k views

### FMCW Radar: Need for Second stage FFT for velocity determination?

I have understood that for the purpose of Range determination, the samples of the beat frequency are first assembled per chirp. The beat frequency is directly proportional to the range of the ...
1k views

### FMCW Radar Working Logic Question

In FMCW radar rather than sending a signal at a constant frequency we are sending a chirp which goes e.g. from 6 GHz to 6.1 GHz in 5 ms. What I cannot fit in my mind is this (numbers are just for ...
386 views

### How should you decide on the number of sweeps to be used in FMCW radar?

I am designing an FMCW radar in MATLAB and I would like to know on how should I decide on the number of linear sweeps in FMCW .Does the number of sweeps affect the performance?
595 views

I purchased a Doppler radar that can run in both CW and FMCW modes. I don't understand how to operate the radar in FMCW mode. I would like to understand what I need to do to get my radar to run in ...
56 views

### Removing Attenuator and Real Mixer influence on the received Baseband signal in Radar IQ Transmitter - De-embedding

Radar IQ Transmitter Measurement Setup: Waveform Generator + IQ Transmitter + Attenuator + Real Downconversion mixer + Oscilloscope + Post-processing (Hilbert Transform) With the above arrangement ...
30 views

### Which is the proper input for the MUSIC algorithm, in the context of Angle of Arrival determination?

I am trying to code a MUSIC algorithm in Python, to process FMCW radar signal and get the angle of arrival (AoA) of targets. I have computed the range, velocity and AoA via 3D FFT, and I am now ...
37 views

### Range-Azimuth Heat map (FFT)

I have a question regarding performing a 2D complex FFT on a 2D array of frequency information in one dimension and azimuthal change in degrees in the other dimension. That is, I ran a test with an ...
24 views

### What input is most appropriate for CFAR processing in FMCW radars and why?

I am estimating range, velocity, angle of arrival from a FMCW radar. To detect potential target candidates points in this 3D domain, I am using a OS-CFAR after the doppler-range to detect the ...
94 views

### How can radars find the elevation angle of a target?

I know that radars can find the azimuth of a target in the angle at which they receive the peak of a reflected signal, but, how can they find the elevation of a target? I know that modern phased array ...
110 views

### Motion detection with FMCW radar

I am studying the work of a microwave rangefinder and faced such a problem, but before that, a preface: I have a microwave module that operates at 24GHz. I use a 1kHz triangle waveform as the ...
30 views

I don't have much experience with radar signals. I know in the cellular system, the channel directional vector can be estimated using pilot symbols based on MMSE, EW-MMSE, and LS. Then, we can use the ...
53 views

### How to reduce phase noise in radar?

Instability of oscillator can introduce phase noise to the signal received by radar [1]. Are there commonly used digital signal processing methods can reduce the phase noise? [1] Aubry, Augusto, et al....
40 views

### Faster way to Implement a CFAR (window average) Threshold

I implemented a version of a CFAR average in MATLAB but it's 'slow' and I need to speed it up. I included the pseudo code and logic below. I used a nested for loop to calculate the moving average but ...
61 views

### FMCW radar transmitter signal splitter

An FMCW radar generates a chirp signal in the transmitter. The chirp is transmitted through a splitter device to both the TX antenna and the mixer in the receive path. Some object generates a ...
83 views

### Create a Range Doppler Map using "Arbitrary" phase coded Waveforms

This is my first questions I am asking to this community! I want to understand how to create a Range-Doppler Map (RDM) for a phase/frequency coded radar return using an arbitrary waveform generator (...
166 views

### Is there processing gain for FMCW using heterodyne-style receiver as opposed to matched filter?

Beat signal of a single target will be a sinusoid in the idealized world, so theoretically the signal processing gain of an FMCW pulse correlated with Tx waveform in this way should be analogous to ...
82 views

### Beginner Educational Resources

New member here. Recently got hired into a mid level EE position. Have a BSEE but performed more radar performance analysis at a higher system level previously. In my new group we're doing a lot of ...
90 views

### FMCW range doppler response problem

I'm trying to learn radar simulation using Matlab. I used this example in Matlab https://www.mathworks.com/help/driving/ug/radar-signal-simulation-and-processing-for-automated-driving.html But when I ...
30 views

### Beamforming and AoA with a small number of elements

So I have an antennae array with only three elements. I want to know what kind of beamforming and AoA estimation I can do with such a small number of elements. I understand that there are lots of ...
92 views

### How does the Hilbert Transform extract the in-phase and quadrature phase components of a real passband signal?

I am taking an intro to radar signal processing course and we are discussing the Hilbert Transform and how it take a real input and its output is analytically complex. I'm trying ) how a radar ...
47 views

### SAR spotlight raw signal database

For practicing spotlight processing, i am looking for I/Q baseband signal from a SAR airborne or spaceborne system. In my research I have only found processed image from : eoweb geoportal https://...
48 views

### Advice on generating stable FMCW waveform

I am trying to derive parameters for a triangular FMCW waveform such that the phase of the signal has consistency from one period to the next. Perhaps this is arbitrary and feel free to tell me so, ...
36 views

### Transceiver for TDoA measurements

Could someone advise me on some module for making the TDoA position system for my research work? I need to have measurements with an accuracy of a few meters. It equals a bandwidth of about 20 MHz. I ...
55 views

### How do you perform range compression of SAR data on a 2D matrix?

I am building a Matlab program to process RADARSAT-1 data that came with this book. The book describes the steps to creating SAR image as follows I am currently implement the range compression step. ...
32 views

### How can i identify number of return of the ping in the sonar?

I am writing a fake function which is actually doing active pinging (basically SONAR). I am little confuse here about how to identify the number of sonar return i got ? Let's say i am continuously ...
153 views

### FMCW Radar using FSK Superimposed LFM ramp

While reading the datasheet of the ADF4159 I came upon a section describing how to create an FMCW ramp with FSK superimposed to "enable unambiguous (distance and velocity) multitarget detection&...
146 views

### Cant find Doppler shift with LFM signal

Im stuck on this one. I hope someone helps me! Problem: I need to find Dopler shift with array of reflected chirps. I have bursts of chirps which then i sampled, and calculated fft. Im suposed to ...
108 views

### How to calculate FMCW Radar Chirp STFT?

I have received signal from FMCW Radar which is of the shape [128x64] = [Number of samples per chirp x Number of chirps per cycle] and i want to calculate the stft i am calculating it with stft ...
50 views

### Does a time varying gain (AGC) mitigate clutter in radar signals?

Trying to implement an MTI filter for flatland clutter in a radar received pulses. However, after the matched filter output instead of implementing directly the MTI filter, I normalized with an ...
145 views

### FMCW radar: Linear phase change determination with sinusoidal decomposition

I am struggling to understand how linear phase shift can be determined with a transform whose main purpose is to determine frequencies rather than rate of change of a function. In FMCW radar, ...
89 views

### Identify an obstacle in front of the radar

I use the K-LC6 24 GHz microwave module in the linear frequency-modulated signal mode to determine the distance to moving objects. But if I put a barrier in front of this radar while it is moving, I ...
107 views

### Digital beamforming and phase shift stage insertion

I have read some literatures about the different topologies of beamforming and it came to my mind a question : where is applied the phase shift for each channel depending on the type of topology/...
64 views

### Is it possible to observe more area in azimuth than physically traveled in stripmap SAR?

I have been examining stripmap SAR algorithms, mainly Range Migration Algorithm. When I check the textbook examples so far I always saw the data trajectory is larger than scene that is observed. An ...
360 views

### Stolt interpolation and ifft in range migration algorithm

I am using range migration algorithm for focusing stripmap synthetic aperture radar data. I have successfully tested my algorithm using the following steps after range compression (similar to this ...
51 views

### 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. ...
202 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 ...
35 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 ...
75 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 ...
33 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).
55 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 ...
322 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 ...
67 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 ...
216 views

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 ...
199 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 ...
112 views

### 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 ...
3k views

### Correct Radar Range Equation for SNR at Detection

Assuming you'd like to estimate the probability of detection of a target for a monostatic radar. For estimating detection SNR of a monostatic radar for given target rcs signature, do you use the ...
2k views

### Angle of arrival (AOA) estimation using FMCW radar using MUSIC algorithm

I am working with FMCW phased array radar with only upchirps. The range doppler matrix is obtained using the two dimensional fast Fourier transform on multiple chirps. I want to obtain the angular ...