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It's so that the cross-range (along-track) resolution is consistent for all targets in the scene. There is no reason why you could not use the flight path between [-5,5] to form the same size image. H …

A returned radar pulse, on the other hand, will contain reflections from a much larger angle, which at typical standoff ranges could mean kilometers-worth of targets. … However, there are ways to coherently process radar data to compensate for the wide beamwidths. …

This will be determined by the targets at the far edges of the scene, where the least amount of rotation relative to the radar is observed. …

Perhaps this will help. The simplest point target simulator that doesn't consider platform motion during the transit time of the pulse can be written in a couple lines of code like this: tau_mcp = col …

The bandwidth is usually always available from the meta data distributed with the radar data, though not sure about the pulse duration. … The ESA makes all of their Sentinel-1 radar data available. It's course range resolution data that covers very large ground areas, so it's probably not dechirpped on receive. …

Since you can equate pulse number with time, if you take just the FFT in the range dimension, you will have frequency vs. (slow-)time for each channel. If you want to look at frequency vs. fast-time, …

For a stationary radar that is trying to image moving targets in the sky, the PRF might be set based on the expected min and max radial velocity of the targets. …

The short answer of what makes a waveform "Doppler tolerant" is that a frequency shifted version of the waveform still has all of its non-linear phase (in the frequency domain) removed when matched fi …

Dechirping is a bit different than matched filtering, but perhaps that not important here. The code you have looks like it should work if the variables are as you describe. Here is a hypothetical exa …

The goal of the radar is to measure/estimate the ground/target reflectivity. If it is peaky, then that is what we want to know. The convolution model is not an approximation. … When sensed by the radar, we see: $ s(t) = \alpha_1 \delta( t - \tau_1) + \alpha_2 \delta( t - \tau_2 ) \Rightarrow r(t) = w(t) \ast s(t). $ For cases where a target's reflectivity is a function of frequency …

See if the example code below helps you. It also looks like you are calling spectrogram wrong; the fourth argument should be a vector of the frequencies at which to compute the spectrogram. You are pa …

The signal that comes back to the radar is delayed by $\tau$ seconds: $w(t-\tau) \cdot e^{j2\pi f_0 (t-\tau) }$. The first thing the radar will do is baseband this signal so that it can be digitized. … Assuming you have a coherent radar, which nearly all are nowadays, this means that what gets digitized is $$ w(t-\tau) \cdot e^{j2\pi f_0 (t-\tau) } \cdot e^{-j2\pi f_0 t} = w(t-\tau) \cdot e^{-j2\pi f …

The following is quick and dirty, but hopefully it helps: % Radar, signal, and simulation parameters. c0 = 3e8; pri = 5e-6; pw = 2e-6; CPI = 0.5e-3; B = 100e6; f_c = 40e9; fs = B * 1.25; % Function that …

Now suppose the target is moving with velocity $v$ and at time $t=0$ its distance to the radar is $r_0$. …