Questions tagged [radar]
Anything related to RADAR (RAdio Detection And Ranging) systems, their operations and circuits. RADAR systems are used to detect and locate a target by sweeping a beam of microwaves across a region of space and detecting echo signals reflected by the target.
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Skills to build an airborne radar [closed]
I am currently working on a project to develop an airborne ground penetrating radar - a payload to be put on a drone - we are aiming to develop a synthetic aperture ground penetrating radar of this ...
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Keysight vs Tektronix: AWG+RT SigAn or VSG+RT Oscilloscope?
I'm evaluating some new RF hardware for one of my university's research labs, for antenna testing. We are between a Keysight vector signal generator and a real-time oscope versus a Tektronix AWG and a ...
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Radar received RF signal phase-shifted by 90 to obtain I/Q signals
I am trying to get idea how marine radar works before start any repairing process. And this part confused me, most articles that i saw explain that in mixing stage we obtain I/Q signals using LO ...
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Advice on measuring relative speed and position of an active transmitting and reveiving object
Using multiple transmitter/receiver stations on ground and the doppler shift to measure relative velocity and position of an airborne active receiver/transmitter in low altitude (0-2 km).
I want to ...
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How is Doppler beam sharpening and synthetic aperture forming the same thing?
There's a quote here from Carl Wiley, the inventor of synthetic aperture radar:
"I had the luck to conceive of the basic idea, which I called Doppler Beam Sharpening (DBS), rather than Synthetic ...
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Chirp pulse compression as described in Stimson's book
I reference the below diagram, from Stimson's Airborne Radar, 2nd Ed. In the text he discusses how the frequency increases linearly throughout the duration of tau. The sketch of the frequency x time ...
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LED limit to short pulse and high power
I’m studying the viability of a small footprint distance detector that relies on a LED, a photodetector and some lenses. It’s meant for a distance above 150m, where the light beam travel time is ...
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SAR: Why can images have complex pixels?
I come from an astronomical long-baseline interferometry background, where images are synthesized from sampled complex visibilities (Fourier components). LBI and polarization can be combined when ...
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FMCW or FSK radar signal processing using an Arduino Nano
I have been trying to build a car detection system with range measurement using an Arduino Nano, an AgilSense AP88 (this provides I/Q output, butI am using only the I output,) and an MPU4725 DAC (...
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Recommendation for 5 V, >2.5 A supply brick with 2.1 mm barrel jack (center positive) power supply
I purchased an AWR1843BOOST automotive radar sensor evaluation module. The power supply must be purchased separately.
The specifications say I need a 5 V, >2.5 A supply brick with a 2.1 mm barrel ...
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Antenna synthesis using Fourier Transform method
My attempt at formulating an answer for part i:
Questions: Am I going in the right direction?
The result of the integrals is not a sin(x)/x function like I was expecting and I don't know how to plot ...
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Why doesn't CDM324 (CW doppler radar) work as an FMCW radar when a fluctuating voltage is applied
Yes, I know CDM324 is a doppler radar module, however, Signal Path posted a nice video taking a deep dive into this module and observed that when the VCC applied is varied between 4 and 5 volts there ...
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Is it possible to couple Tx signal to RTL-SDR Rx signal for a FMCW radar?
Above one can see a typical (AFE) diagram for a FMCW. Other block diagrams I found include the processing blocks and and so on as well, but my question rests on the following: can I mix the TX and RX ...
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What is the bandwidth of a radar operating at 5 GHz?
This is the question I have been working on recently. I am trying to figure out how the time-bandwidth product is calculated.
If anyone can send me any useful links that I can learn from I'd be very ...
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What methods can be used for sampling an analog signal using a microcontroller?
I'm in the early stages of design a project I'm working on for fun - a radar speed detector using a simple Doppler radar module and an Arduino (or possibly another similar microcontroller).
I've ...
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Basic question about radar
I am learning about automotive radars and have a very basic question about them.
If two or more cars on a road have the same radar, using the same radar tech (e.g. CWFM radar) how will one car's radar ...
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What kind of low-cost equipment do I need to learn and experiment with RADAR at home?
I am interested in RADARs. However, I don't have enough time to go to school for studying RADARs. Therefore, I am thinking about self-study.
What kind of low-cost equipment do I need to learn and ...
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A question on radar cross section of rain by using radar reflectivity factor
The question is one of the past exam papers of the RADAR 1 course given in TUDelft, unfortunately, solutions are not provided to the past paper yet.
The question:
What will be the radar cross-section ...
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How could you determine the point in time a Radar antenna is directly facing a stationary RF receiver station?
I am currently doing experiments involving Software Defined Radio and Radar systems. Since I am new in this field and currently try to refresh my physics/math skills, I encountered some problems along ...
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Is it possible to build radar system for drones detection at home? [closed]
Can I build DIY radar system using ESP32 or Raspberry Pi modules + a bit of soldering that will be able to detect drones in a radius 1-2km? Is it possible? What do I need for this and how much will it ...
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Range Profile in Radar System
I am slightly confused on the range profile I am obtaining from my SCFW radar dataset. I am understanding of how fftshift works in shifting positive and negative frequency components to be centered ...
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Frequency response of antennas
Electromagnetics and antennas are not my main area of expertise. However, I have a specific question about antennas that I want to get right in order to make sure my signal processing is right.
What ...
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Active Radar Homing with single antenna
From what I remember there are a few A2A and S2A missiles which have their own onboard radar system but I don't think they have multiple radar antennas for phased Array use.
I'm curious how radar ...
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Using LIDAR in a 360-degree configuration
(I do not know an appropriate place for this on Stack Exchange. There does not appear to be any groups dedicated to LIDAR or ranging, so this will do for now. Please let me know if there is a better ...
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Creating a Range Profile
I am relatively new to the radar/signal processing community. However, my team has been struggling in developing a range profile in our programming. Here are the details for a NI LabVIEW forum I ...
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Why does an isotropic antenna becomes anisotropic inside a phased array (mutual coupling neglected)?
in this paper the following statement is written:
An area A is allotted to each element in the infinite array. This is
the maximum area available to each element, and is usually greater
than the ...
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Radial velocity of two moving targets [closed]
The radial velocity is the velocity which is in the direction of the connecting line.
I would like to find the Doppler frequency of two moving targets, but as you know, this frequency only shows me ...
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Problem in the book "Radio Antennas and Propagation"
I came across a problem in an electronics textbook by William Gosling, Radio Antennas and Propagation.
I am an undergraduate and I sent this to my lecturer to help solve but unfortunately, her answer ...
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Why are many radar antenna arrays not rectangular but rather octagonal÷icosagonal?
I've seen that, despite some phased array antennas are rectangular, many of them are not. They are octagonal, decagonal and even more.
Why are they built in this way?
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How does the author get to his equation for the ellipse and the antenna's beam?
I am trying to understand how the author of this textbook (Basic Radar Analysis by Mervin C. Budge) realizes the equation for the ellipse shown in the image attached labeled Figure 2.3 (found in ...
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Confusion on what the RF input to a PLL does
I am designing an FMCW radar, for which I need to generate an RF signal ramped in frequency. To accomplish this, I want to use a direct digital synthesizer (DDS) to generate the ramp at baseband then ...
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Can traffic counting be done with just doppler radar?
I'm planning on using radar to count car traffic on a slow speed road. What I'm wondering is if I should expect doppler radar to be good enough to get an accurate count? Alternatively I could also use ...
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Need help with the choice of a motion sensor for use in arctic temperatures
We are a group of students, who are currently investigating how to build a robot that is meant to work at arctic temperatures (peaks at roughly -30 degrees Celsius). We would like to equip our robot ...
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Why is my clipping circuit involving 1N5819 Schottky diodes in my radar receiver not working?
I have built the circuit shown below and been testing it on a breadboard.
Everything works except the positive half clipping circuitry.
I need it to clip after 3.3V. It currently just clips below 0V, ...
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Low Voltage Oscillation in OpAmp Circuit
I have a small signal from a radar sensor (in the range of 300 µV) which I want to amplify to something I can reliably measure. Fortunately the application notes of the sensor provide a recommended ...
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Uniform circular array (UCA) beamforming using FFT
As far as I know, conventional beamforming using FFT can return a range-angle map. However, this only works with a uniform linear array (ULA).
I'm wondering if the same approach works for UCA. I guess ...
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How do I compute the angular resolution of a radar system?
I hope this is the right place to ask a radar related question, otherwise I would be grateful for a pointer to the correct forum.
I want to compute the angular resolution of a radar system but so far ...
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What is the difference (and the link) between the RADAR cross section (RCS) and the equivalent area of the target?
Here it is written that:
The radar cross section (RCS) σ of a target is the equivalent area seen
by a radar. It is the fictitious area intercepting that amount of
power which, when scattered equally ...
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What is the purpose of range gating in a tracking mode of a Radar?
I am trying to understand what happened in the famous incident where the Patriot failed to intercept a Scud missle because of a software bug.
The reprot can be found here.
Why does the radar need to ...
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Which is the cause of "scan losses" in a linear phased antenna array?
in a linear phased array it is possible to move the peak angle ("beam steering") by applying proper phase shift between the excitation currents:
The second picture represents the array ...
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Pulse Doppler radar system simulation using MATLAB
How to code this project in MATLAB
I'd tried coding this project (prob. 3-2, third paragraph) in MATLAB through this tutorial :
https://www.mathworks.com/help/phased/ug/doppler-shift-and-pulse-doppler-...
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STM32 DMA for IQ modulation
I’m trying to develop an application where I use an STM32F405RGT6 microcontroller IC to drive a radar that operates in multiple ISM bands (433.92 MHz, 915 MHz, 2.4 GHz, and 5.8 GHz).
The overall idea ...
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FMCW Radar Signal Processing based on MIT Open Course
I am working on a self-made FMCW radar - for the signal processing, I am using the MIT open course (https://ocw.mit.edu/resources/res-ll-003-build-a-small-radar-system-capable-of-sensing-range-doppler-...
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Friendly target identification in radar
Crossposted from Signal Processing stack exchange,
How do radar systems identify friendly targets to avoid AA locks during combat scenarios?
Do friendly planes broadcast a known signal or is something ...
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Is the impulse response of a real system is always a real function?
As stated in the title, is the impulse response of a real system is always a real function? Can it ever be complex/analytic, etc.? I'm more interested in terms of radar systems. Any info would be ...
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Estimating Safe Pulsed RF Power given Continuous Wave Power Rating
For a university project I am designing a RADAR transmit/receive module at 9.4 GHz. Right now I'm working on an input power limiter to protect an LNA, but my colleague designing the LNA quotes its ...
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Building a 77GHz Band FMCW Radar with 0.25 Degree Angular Resolution
First some context. My group recently acquired some hardware for a radar related project, specifically a Texas Instrument AWR1843Boost (https://www.ti.com/tool/AWR1843BOOST) and a Texas Instruments ...
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FMCW radar FFT(Fast Fourier Transform)
I am trying to design a simple FMCW radar for the ideal case. Below are steps I planned.
Transmit signal, Tx = cos(T)
receive signal, Rx = cos(R)
Mix transmitted signal and received signal, Sx1 = cos(...
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What is beam coupling coefficient for linear beam klystron?
What does beam coupling coefficient exactly tell? For eg. a voltage gain coefficient tells how much times the input was amplified. So what does beam coupling coefficient tell, like does it tell how ...
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Typical power reflected off wall/window/wooden shelves etc
For interference purposes, I would like to quantify how much signal power I would receive back when my transmitted signal is reflected off an object (a wall, glass window, wooden shelf) at a distance ...
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