Preview
I made this simulation as a project in a course I took in RADAR basic concepts.
The RADAR is an Early Warning RADAR. The simulation simulates targets around the RADAR, calculates the
expected return pulses and adds noise. The simulation works at the Intermediate Frequency (IF) level and I assume
perfect phase reconstruction by the RADAR.
Quick start
1. Run "radarSimulation.m".
2. Press “Start”.
Details
It is a simulation of an early warning radar. The simulation generates random targets (coordinates, velocity,
acceleration & Radar Cross Section (RCS)).
For each radar pulse the simulation calculates the returns that the radar will receive from all the targets according to
the radar formula (taking into account transmission power, antenna gain, targets distance & targets RCS). The
simulation calculates the amplitude & phase of the return signal (according to the IF frequency).
The radar builds a vector of its samples as complex signals (representing amplitude and phase delay) and adds it to
complex random RF noise. The vector goes through a LPF representing the receiver BW and then I add another
complex random noise representing the radar's thermal noise (in the digitizer).
The radar saves several reception periods to a buffer and then processes the entire buffer. The radar can perform a
match filter over the received signal. The radar analyzes each range cell in the buffer in search of a target.
Detection threshold can be fixed or dynamic according to the buffer statistics (a sort of Constant False Alarm Rate
(CFAR)).
In case Moving Target Indicator (MTI) is used the target detection is done in the frequency plane of the complex
signal.
Each detected target is plotted on the main radar display. In case MTI is used a representation of the target’s velocity
is also plotted (stationery targets are plotted as mountains). Take notice that the radar can only estimate the relative
velocity between the target and the radar (any tangent velocity is lost).
Professor comments
My professor had several remarks about how bad this simulation is (the remarks were made on the previous version; I
worked to correct some of them in this version). His remarks where:
- My match filter isn't really matched (it's true I matched it to square pulse and not to a band limited pulse).
- My noise levels have wrong units and aren't realistic (it might be true but you can control it as you wish so it isn't a
real problem).
- Moving Target Indicator doesn't work the way I implemented it (might be true but I think my way is really good).
- The CFAR mechanism doesn't exist (yep I got sloppy but you can easily control the threshold so it's good enough
and it is still just a simulation for a very small course!).
